Peri-Implant Bone Stability Around Tapered Implant Prosthetic Connection: A Systematic Review and Meta-Analysis Comparing Different Cone Morse and Conometric Implants Angle Contact and Coupling Interface Designs

Iris Alla; Antonio Scarano; Bruna Sinjari; Edit Xhajanka; Felice Lorusso

doi:10.3390/app15031237

,

and

¹

Department of Innovative Technologies in Medicine and Dentistry, University of Chieti–Pescara, 66100 Chieti, Italy

²

Department of Dental Medicine, Medical University of Tirana, Rruga e Dibres, 1001 Tirana, Albania

^*

Author to whom correspondence should be addressed.

Appl. Sci.2025, 15(3), 1237;https://doi.org/10.3390/app15031237

This article belongs to the Special Issue Implant Dentistry: Advanced Materials, Methods and Technologies

Version Notes

Order Reprints

Abstract

Background/Objectives: Internal implant–abutment connection has been proposed to increase interface stability and reduce biological and prosthetic issues. The aim of the present investigation was to evaluate the influence of the implant abutment conical angle on marginal bone loss and mechanical complications. Methods: The literature screening was performed by considering Pubmed/MEDLINE, EMBASE, and Google Scholar sources. The eligibility process was conducted in order to perform a descriptive synthesis, determine the risk of bias, and carry out network meta-analyses. The following categories were considered for pairwise comparisons: external hexagon (EI), internal hexagon (HI), cone morse (CM) (<8° contact angle), and conometric joint (>8° contact angle). For the descriptive data synthesis, the following parameters were considered: sample size, implant manufacturer, prosthetic joint type, prosthetic complications, marginal bone loss, and study outcomes. Results: A total of 4457 articles were screened, reducing the output to the 133 studies included in the descriptive synthesis, while 12 articles were included in the statistical analysis. No significant differences in marginal bone loss were reported when comparing a cone angle of <8° and a cone angle of >8; Conclusions: Within the limits of the present investigation, the cone interface seems to produce lower marginal bone loss compared to external and internal hexagon connection. No differences were found when comparing a cone angle of <8° and a cone angle of >8°.

Keywords:

dental implant; implant–abutment connection; implant-supported dental prosthesis; prosthetic loading

1. Introduction

The dental implant procedure represents a durable and highly predictive technique for edentulism treatment and oral rehabilitation. Considering the medium- and long-term function period, a key factor for dental implant success is the maintenance of healthy peri-implant tissues healthy and the preservation from marginal bone loss. Crestal marginal bone loss (MBL) around a dental implant is common in clinical practice; historically, Albrektsson et al. described a MBL of <0.2 mm/year after the first year of functional loading as one of the key factors for success in implantology [1]. Due to the complexity of this aspect, MBL should be considered a condition that is clinically supported by multifactorial conditions, which are both local and systemic [2,3].

The implant–abutment joint has been described as a key factor for two-stage implantology regarding the related biological and biomechanical implications. A submerged healing implant protocol is reported as a supportive procedure able to preserve the device from the pathogenic noxae induced by biofilm formation and proliferation, addressing the issue of osteointegration during the early healing phases [2,3]. The one-stage healing protocol, including the immediate functional loading, could emphasize the biological and bacterial exposure associated with the mechanical solicitations on the implant joint components, producing a ponderable risk to the peri-implant tissue stability [4]. Since evidence suggests that crestal alveolar bone resorption occurs as a result of the micro-gap present between the implant–abutment interface in dental implants [5], two-stage implantology, with the submerged implant protocol, prevents early colonization by bacteria, especially in the early stages of osseointegration, as well as local inflammatory stress during the bone healing process. On the other hand, there are also the implications of important biomechanical stresses to consider, such as the functional load to which the implant is subjected at the level of the peri-implant marginal components and which, therefore, leads to important instability in the peri-implant soft and hard tissues [2,3]. Immediate functional loading, on the other hand, could emphasize stresses at the level of the peri-implant marginal components and, thus, produce substantial instability in the peri-implant soft and hard tissues [5,6]. Therefore, the design of the implant–abutment interface, the length and stability of the prosthetic joint, and the tolerance of the platform components play a key role in creating a hypothetical bacterial reservoir and maintaining a chronic inflammatory state, triggering peri-implant marginal bone loss (MBL), a complication that after implant insertion exerts a significant influence on the future success and long-term stability of the implant [7]. In the literature, implant success is considered with an MBL of −1.5 mm during the first year after loading and <0.2 mm/year thereafter [1,8,9]. Since peri-implant marginal bone resorption is a multifactorial onset condition, among the various factors related to bone resorption is the peri-implant inflammatory reaction, defined as a consequence of bacterial colonization at the interfaces of dental implants [10]. In fact, after a few seconds of exposure of the implant surface to the oral environment, the process of biofilm adhesion sets in [10].

Such bacterial adhesion can lead to the formation of a true bacterial reservoir at the micro-gap level of the prosthetic joint, resulting in chronic inflammation in the surrounding tissues, which inevitably leads to marginal bone loss [11]. A mismatch generated by the prosthetic abutment joint components leads to microleakage, such that a pump effect is generated under a functional load [11,12]. It follows that in order to reduce marginal bone loss, it is of fundamental importance to prevent bacterial microleakage, a necessary condition for the design of transmucosal dental implants. In this regard, there are several prosthetic joint designs also documented in the literature that provide different implant interfaces [13,14]. The most common implant joints include the external connection, the internal connection and the conical/cone morse joint [9,15,16]. The aim of this systematic review and meta-analysis was to determine the influence of the internal conical connection angle in terms of marginal bone loss.

2. Materials and Methods

2.1. Preliminary Screening Strategy

The electronic screening was conducted in accordance with the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-analyses) and searched the Pubmed/MEDLINE, Google Scholar, Scopus, and Web of Science databases using the following keywords: (taper OR cone OR conical OR Cone morse) AND dental implant (Table 1). The PICO question is detailed as follows:

Table 1. Search strategy for the electronic database screening.

(1): P = population/patient/problem—subjects needing a dental implant for prosthetic rehabilitations;
(2): I = intervention—dental implant treatment positioning and fixed oral rehabilitation;
(3): C = comparison—comparison between different internal, external and conical prosthetic joints;
(4): O = outcome—marginal bone loss; major prosthetic complications.

The review process was registered in the NIHR—National Institute for Health and Care Research PROSPERO Database.

2.2. Inclusion Criteria

Articles written in English language were included with no restrictions regarding their date of publication. The titles and abstracts list was considered for a first-level initial screening by two independent reviewers (FL and IA). Clinical trials were included in the descriptive synthesis and meta-regression. For the descriptive synthesis and NMA, only the studies that investigated internal conical implant–abutment joint were considered for the present investigation. The exclusion criteria were implants with a bone regeneration procedure, in vitro studies, in silico studies, literature reviews, articles written in a foreign language, animal studies, zirconia implants, technical notes, and book chapters.

2.3. Study Data Extraction

The following parameters of the study data were extracted from the selected studies: publication date, study model design, population size, age, marginal bone loss, prosthetic complications, and follow-up. For this review, a specially designed electronic database form was used (Excel, Microsoft Office 360, Redmont, WA, USA).

2.4. Risk of Bias Assessment

The risk of bias (RoB) was measured using the OHAT tool while considering the studies included for the qualitative analysis. The RoB categories were low risk (lr), undefined risk (ur), and high risk (hr) [17].

The RoB analysis considered the following studies classes: randomization sequence, allocation, blinding of subjects and operators, outcomes measuring blinding, attrition bias, reporting bias, and other biases [17]. The RoB was calculated using the Review Manager software (RevMan 5.0, The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark).

2.5. Heterogeneity Measurement and Meta-Analysis

The meta-regression was conducted using the freely available package for continuous variables using a full R code [18]. A Bayesian network meta-analysis was conducted, considering random effects hierarchical models. The forest plot was used to evaluate the significance and the consistency of the ranks. The I2 test considered a low heterogeneity result to have a value <40%, while a high heterogeneity result had an I2 test > 40%.

3. Results

3.1. Screening Output

A total of 4457 articles were detected during the electronic database search, and a total of 56 records were removed because they were duplicates. A total of 4401 papers were considered for the abstract assessment, and 2491 records were removed because they were off-topic. The full-text article was obtained for a total of 1910 manuscripts, and these were submitted for the eligibility assessment. A total of 1775 articles were removed for the following reasons: 505 papers described a contextual bone regeneration procedure, 586 described in vitro experiments, 210 described in silico investigations, 153 were literature reviews, 127 papers were written in a language other than English, 127 were pre-clinical studies conducted on animals, 59 were case reports/case series, 5 articles described a zirconia implants procedure, 2 were technical notes, and 1 was a book chapter. A total of 133 studies were included in the descriptive synthesis, and 12 articles were included in the meta-regression assessment (Figure 1).

Figure 1. Screening of papers in accordance with the PRISMA guidelines [19] [** the step has been conducted by human with no automation tools].

3.2. General Characteristics of the Studies Included

The cumulative population sample was 19,637 patients [median: 44; mean: 141.27; sd: ±587.70], while a total of 44,109 implants were assessed [median: 88; mean: 329.18; sd: ±1134.0]. Different platforms were evaluated in the present investigation including: (1) cone morse [<8° internal angle] [20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128], (2) internal conical connection [>8° internal angle] [27,30,58,120,122,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147], (3) external hexagon [30,39,56,57,64,78,86,102,120,122,127,132,140], (4) internal hexagon [20,39,58,63,64,65,67,68,78,122,130,133], (5) internal octagonal butt-joint [108], (6) internal polygonal butt-joint [148], and (7) internal trilobate joint [72] (Table 2). A total of 1 case-control, 5 cohort prospective studies, 4 cross-sectional studies, 58 non-randomized clinical trials (CTs), 28 randomized clinical trials, and 44 retrospective studies were included in the analysis (Table 2).

3.3. Complications

The most common prosthetic complications were crown loosening [29], chipping and veering material fracture [23,24,29,30,31,34,35,38,94,96,129,130,141,145], abutment fracture [21,28,31,32,95,110,112,118], screw loosening and fracture [20,21,22,31,32,33], aesthetic issues [24], osseointegration failure [36], marginal bone resorption [119,149], and implant joint and body fracture [21,28] (Table 2).

Table 2. Descriptive synthesis of the selected papers.

Author	Journal	Year	Study Design	Population	Implant	Producer	Cone Morse Angle	Connection	Methods	Prosthetic Complications
Canullo L [79]	J. Prosthet. Dent.	2022	Retrospective study	43 participants	48 implants	Premium Kohno; Sweden & Martina Prama; Sweden & Martina (tissue level)	NA	Cone morse	Clinical and radiographic assessment	__
Degidi M [23]	Int. J. Periodontics Restorative Dent.	2018	CT	76 patients	156 implants	Ankylos, Dentsply	5.7°	Cone morse	Clinical and radiographic assessment	- One fixed prosthesis (0.76%) fractured [41 months] - Chipping
do Vale Souza JP [48]	Eur. J. Dent.	2021	CT	25 patients	25 implants	DSP Biomedical	NA	Cone morse	Clinical and radiographic assessment Insertion torque—ISQ	__
Hartmann R [139]	J. Oral. Rehabil.	2020	RCT	37 patients	47 implants	Neodent TI Cortical, Brazil	11.5°	Conometric	Clinical assessment	__
Sánchez-Torres A [31]	J. Prosthet. Dent.	2021	Retrospective study	56 patients	288 implants	Replace tapered implants: Nobel Biocare AB Multiunit abutments: Nobel Biocare AB	6°	Cone morse	Oral Health Impact Profile (OHIP)	- Abutment screw loosening (43%), - Chipping - Fracture of the veneering material (25%), - Screw loosening (21%).
Sato RK [41]	Implant Dent.	2017	Cohort prospective study	16 patients	16 single implants	Drive cone Morse Acqua, Neodent, Brazil	NA	Cone morse	Clinical and radiographic assessment	__
Abi Rached S [143]	Minerva Dent. Oral. Sci.	2023	CT	7 patients	18 implants	Straumann^® SP cylindrical implants JD Octa^® tapered implants	1:16° 2:15°	Conometric	Clinical and radiographic assessment
Ackermann KL [29]	Int. J. Implant Dent.	2020	CT	94 patients	130 implants	Conelog Screw-Line; Camlog Biotechnologies	7.5°	Cone morse	- Clinical and radiographic assessment - Marginal bone loss	- Crown loosening (3) - Ceramic chipping (1)
Afrashtehfar KI [75]	Evid Based. Dent.	2022	RCT	24 patients	48 implants	Conelog, Camlog Biotechnologies, Basel, Switzerland	7.5°	Cone morse	Clinical and radiographic assessment	__
Al-Fakeh H [92]	J. Stomatol. Oral Maxillofac. Surg.	2022	Retrospective study	65 patients	102 implants	NA	NA	Cone morse	Clinical and radiographic assessment	__
Apaza-Bedoya K [97]	J Periodontol.	2023	Cross-sectional	99 patients	266 implants	NA	NA	Cone morse	__
Baer RA [42]	Clin. Oral. Investig.	2022	Cohort prospective study	67 patients	81 implants	NA	NA	Cone morse	__	__
Baldi D [80]	Minerva Stomatol.	2020	Retrospective study	__	26 implants	NA	NA	Cone morse		__
Bernard L [70]	J. Prosthet. Dent.	2019	RCT	15 patients	89 implants	Ankylos; Dentsply Sirona	5.7°	Cone morse	Clinical and radiographic assessment	__
Cacaci C [45]	Clin. Oral. Investig.	2019	CT	94 patients	130 implants	Conelog Screw-Line implants; Camlog Biotechnologies AG, Basel, Switzerland	7.5°	Cone morse	Clinical and radiographic assessment	__
Cannata M [20]	Eur. J. Oral Implantol.	2017	RCT	90 patients	90 implants	JD Implant, Modena, Italy	5°	Internal hexagon Cone morse	Clinical and radiographic assessment	Screw loosening (2) [HI group]
Canullo L [54]	Clin. Implant Dent. Relat. Res.	2018	CT	22 patients	22 implants	Premium Kohno, Sweden & Martina, Due Carrare, Padua, Italy	NA	Cone morse	Clinical and radiographic assessment	__
Canullo L [91]	Int. J. Prosthodont.	2022	Retrospective study	85 patients	133 implants	NA	NA	Cone morse	Clinical and radiographic assessment	__
Cassetta M [34]	J. Oral Sci.	2016	Cohort prospective study	350 patients	748 implants	NA	NA	Cone morse	__	6 were early failures (0.8%) and 28 were late failures (3.7%)
Cassetta M [38]	Int. J. Oral. Maxillofac. Surg.	2016	CT	350 patients	648 implants	NA	NA	Cone morse	Clinical and radiographic assessment	1 fracture of porcelain surface without metal exposure
Cassetta M [34]	J. Oral. Sci.	2016	CT	270 patients	576 implants	Osseothread; ImplaDent, Formia, Italy	NA	Cone morse	Clinical and radiographic assessment	__
Ceruso FM [133]	Materials	2022	CT	30 patients	30 Implants	1: Nobel Parallel, Nobel Biocare, Swiss (12° Conical connection) 2: Prama, Sweden, and Martina, Italy HI	1: 12° 2:-	Internal hexagon Conometric	Clinical and radiographic assessment	__
Cooper LF [130]	Int. J. Oral Maxillofac. Implants	2021	RCT	141 patients	141 implants	NA	NA	Conometric Internal hexagon	__	Six platform-switched interface and eight flat interface implants failed
Corvino E [67]	Int. J. Oral. Implantol. (Berl)	2020	RCT	33 patients	53 implants	NA	NA	Internal hexagon Cone morse	Clinical and radiographic assessment	__
Dagher M. [60]	J. Maxillofac. Oral Surg.	2022	CT	24 patients	30 implants	UFII, DIOTM, DIO Implant Busan 612–020, Korea	NA	Cone morse	Clinical and radiographic assessment	__
de Melo LA [56]	J. Indian Soc. Periodontol.	2017	CT	23 patients	46 implants	Neodent, Curitiba, Brazi	11.5°	External hexagon Cone morse	Clinical and radiographic assessment	__
De Paoli S [62]	Int. J. Periodontics Restorative Dent.	2023	CT	12 patients	24 implants	NA	NA	Cone morse	__	__
Degidi M [35]	J. Prosthodont.	2018	CT	65 patients	134 implants	ANKYLOS; Dentsply Implants, Mannheim, Germany	5.7°	Cone morse	Clinical and radiographic assessment	- 2 prostheses (3.07%) fractured - 3 patients reported small chips
Degidi M [43]	Clin. Oral Implants Res.	2017	Cross-sectional	145 patients	523 implants	Ankylos^®, Dentsply Implants, Mannheim, Germany	5.7°	Cone morse	Clinical and radiographic assessment	__
Degidi M [61]	Int. J. Periodontics Restorative Dent.	2016	CT	39 patients	78 implants	Ankylos^®, Dentsply Implants, Mannheim, Germany	5.7°	Cone morse	Clinical and radiographic assessment, ISQ	__
Dev SV [131]	J. Pharm. Bioallied. Sci.	2021	CT	20 patients	20 implants	NA	NA	Conometric	__	__
Ding Y [93]	Clin. Implant Dent. Relat. Res.	2023	Retrospective study	33 patients	218 implants	NA	NA	Cone morse	__	__
Doornewaard R [64]	Clin. Implant Dent. Relat. Res.	2021	RCT	25 patients	98 implants	DCC, Southern Implants, Irene, South Africa	NA	Cone morse External hexagon Internal hexagon	Clinical and radiographic assessment	__
Eerdekens L [36]	Clin. Implant Dent. Relat. Res.	2015	CT	10 patients	60 implants	__	NA	Cone morse		2 out of 59 implants failed
Fabbri G [30]	Int. J. Periodontics Restorative Dent.	2017	Retrospective study	601 patients	965 implants	Nobel Biocare Straumann Biomet 3i	1:6° 2: 11.5° 3: NA	External hexagon Cone morse Conometric	Clinical assessment	Complication rates of 1.14%, 3.42%, and 0.62% for fractures, chipping, and unscrewing, respectively
Farronato D [68]	BMC Oral Health	2020	RCT	104 patients	188 implants	Group 1: Anyridge^®, MegaGen, South Korea Group 2: Core^®, Kristal, Italy	5°	Internal hexagon Cone morse	Clinical, radiographic, and digital assessment	__
Fernández-Figares-Conde I [52]	Dent. J. (Basel)	2023	CT	218 patients	218 implants	Proclinic S.A.U, Zaragoza, Spain	NA	Cone morse	Clinical and radiographic assessment	__
Galindo-Moreno P [141]	J. Clin. Med.	2021	RCT	30 patients	30 implants	N35/M12 implant, Oxtein Iberia S.L.	11°	Conometric	Clinical and radiographic assessment	Ceramic chipping (1) [HI]
Gao WM [129]	BMC Oral Health	2021	Retrospective study	392 patients	541 implants	NA	NA	Conometric	Clinical and radiographic assessment	veneer chipping, with a frequency of 67.53%. The complication-free rate for integrated abutment crowns was significantly greater than for gold porcelain crowns; molar regions were significantly greater than premolar regions, females performed significantly better than males.
Ghensi P [44]	J. Craniofac. Surg.	2019	Cross-sectional	120 patients	261 implants	CLC CONIC	6°	Cone morse	Clinical and radiographic assessment	__
Guarnieri R [71]	Int. J. Periodontics Restorative Dent.	2015	RCT	77 patients	78 implants	BioHorizons	NA	Cone morse	Clinical and radiographic assessment	__
Guarnieri R [85]	Implant Dent.	2014	Retrospective study	46 patients	46 implants	BioHorizons	NA	Cone morse	Clinical and radiographic assessment	__
Hamudi N [53]	J. Clin. Med.	2021	CT	21 patients	42 implants	NA	NA	Cone morse	Clinical and radiographic assessment	__
Heydecke G [51]	Clin. Oral. Investig.	2019	CT	94 patients	88 implants	NA	NA	Cone morse	__	__
Horwitz J [59]	J. Oral. Implantol.	2018	CT	60 patients	117 implants	Branemark implants	NA	Cone morse	Clinical and radiographic assessment	__
Jin X [28]	Clin. Oral Implants Res.	2022	Retrospective study	6823 patients	12.538 implants	1: Straumann Bone Level, Straumann AG (contact angle 7.2°) 2: Ankylos, Dentsply Implants (contact angle 5.7°)	1: 7.2° 2:5.7°	Cone morse	Clinical and radiographical assessment	Implant fracture (9): 4 Straumann; 5 Dentsply Abutment fracture (28): 14 Straumann; 14 Dentsply
Koutouzis T [73]	Int. J. Oral Maxillofac. Implants	2014	RCT	30 patients	30 implants	ANKYLOS CX, DENTSPLY Implant Manufacturing	5.7°	Cone morse	Clinical and radiographic assessment	__
Koutouzis T [74]	Int. J. Oral Maxillofac. Implants	2013	RCT	30 patients	30 implants	Dentsply Ankylos System	5.7°	Cone morse	Clinical and radiographic assessment	__
Koutouzis T [82]	Int. J. Oral Maxillofac. Implants	2015	Retrospective study	25 patients	30 implants	Ankylos^®, Dentsply Implants, Mannheim, Germany	5.7°	Cone morse	Clinical and radiographic assessment	__
Kruse AB [78]	Int. J. Implant Dent.	2021	Retrospective study	36 patients	93 implants	1. Ankylos© 2. Branemark© 3. ITI Bonefit©	1:5.7° 2:- 3:-	Cone morse Internal hexagon External hexagon	Clinical and radiographic assessment	__
Lin MI [88]	J. Dent. Res.	2013	Retrospective study	63 patients	103 implants	1: Brånemark System TMMK 2: IV TiUnite, Nobel Biocare, Sweden, 3: Atlas, Cowellmedi, South Korea 4: Ankylos Plus Implant, Friadent, Germany	1: NA 2: NA 3: NA 4: 5.7°	Cone morse	Clinical and radiographical assessment	__
Linkevicius T [138]	Clin. Implant Dent. Relat. Res.	2021	RCT	64 patients	64 implants	MIS Implant Technologies Ltd., Bar-Lev Industrial Park, Israel	12°	Conometric	Clinical and radiographic assessment	__
Linkevicius T [98]	Clin. Oral Implants Res.	2015	CT	__	60 implants	(1) BioHorizons, Birmingham, AL, USA (2) Certain Prevail; Biomet/3i, Palm Beach Gardens, FL, USA	NA	Cone morse	__
Lopez MA [89]	J. Biol. Regul. Homeost. Agents	2016	Retrospective study	66 patients	66 implants	FMD Falappa Medical Devices, Italy	NA	Cone morse	Clinical and radiographical assessment	__
Lops D [90]	Materials	2020	Retrospective study	93 patients	410 implants	Anyridge, MegaGen Implant Co., South Korea	5°	Cone morse	Clinical and radiographical assessment, marginal bone loss	__
Machtei EE [86]	Clin. Oral Implants Res.	2006	Retrospective study	27 patients	73 implants	Osseotite/Osseotite TG (3I Implant Innovations Inc., USA)	8°	External hexagon Cone morse	Clinical and radiographical assessmentMarginal bone loss	__
Mangalvedhekar M [120]	J. Pharm. Bioallied. Sci.	2022	CT	50 patients	__	Nobel Biocare	12°	Conometric External hexagon	Clinical and radiographical assessment	__
Mangano C [94]	Clin. Oral Implants Res.	2015	Retrospective study	49 patients	178 implants	Mac System, Milan, Italy	NA	Cone morse	Clinical and radiographic assessment	Prosthetic complications (10.3%)
Mangano F [24]	Int. J. Environ. Res. Public Health	2019	Retrospective study	25 Patients	40 implant	Exacone^®, Leone Implants, Florence, Italy	NA	Cone morse	Full-digital Protocol (SCAN-PLAN-MAKE-DONE^®)	Occlusal issues (2/40 crowns: 5%), interproximal issues (1/40 crowns: 2.5%), and aesthetic issues (1/40 crowns: 2.5%). Overall incidence of issues at delivery of 10% (4/40 crowns).
Mangano F [55]	J. Craniofac. Surg.	2018	CT	578 patients	612 implants	Leone Implants, Florence, Italy	NA	Cone morse	Clinical and radiographic assessment	__
McGuire MK [72]	Int. J. Periodontics Restorative Dent.	2015	RCT	12 patients	12 implants	(1) OsseoSpeed, Dentsply Implants (2) NobelSpeedy Replace, Nobel Biocare (3) NanoTite Certain Prevail, Biomet 3i	1: NA 2: NA 3: NA	Cone morse	Clinical and radiographic assessment	__
Melo LA [57]	Braz. Dent. J.	2017	CT	20 patients	40 implants	Neodent	11.5°	External hexagon Cone morse	Clinical and radiographic assessment	__
Meloni SM [76]	Dent. J. (Basel)	2020	Retrospective study	82 patients	152 implants	NobelReplace CC PMC or NobelReplace Tapered Groovy	6°	Cone morse	Clinical and radiographic assessment	__
Mihali SG [136]	J. Oral Implantol.	2021	RCT	49 patient	98 implants	Mis Implant System	12°	Conometric	Clinical and radiographical assessment	__
Moergel M [22]	Clin. Oral Implants Res.	2021	CT	24 patients	52 implants	Conelog Screw-Line; Camlog Biotechnologies	7.5°	Cone morse	Clinical and radiographical assessment, marginal bone loss	Screw fracture (1)
Moroi A [69]	Clin. Implant Dent. Relat. Res.	2020	RCT	43 patients	88 implants	Nobel Biocare, Sweden	6°	Cone morse	Clinical and radiographic assessment ISQ	__
Naumann M [37]	Clin. Oral Implants Res.	2023	RCT	20 patients	-	NA	NA	Cone morse		1 restoration failed after 6 months due to the loss of the abutment interface.
Obreja K [25]	Int. J. Periodontics Restorative Dent.	2022	Cross-sectional	44 patients	57 implants	NA		Cone morse	Clinical and radiographical assessment	None
Oda Y [39]	Clin. Oral Implants Res.	2021	Retrospective study	65 patients	592 implants	1: Brånemark system implant 2: Ankylos implant 3: Straumann system tissue-level implant—Zimmer screw-vent	1: NA 2: 5.7° 3: 7.2°	Internal hexagon External hexagon Cone morse	Clinical and radiographical assessment Marginal bone loss	__
Ogino Y [66]	Int. J. Oral Maxillofac. Implants	2021	RCT	25 patients	30 implants	GC Aadva implants	NA	Cone morse	Clinical and radiographical assessment, marginal bone loss	__
Paganelli OEB [132]	Gen. Dent.	2022	CT	9 patients	36 implants	NA	NA	Conometric External hexagon	Clinical evaluation via magnetic transduction resonance frequency analysis	__
Palaska I [148]	Clin. Oral Implants Res.	2016	RCT	81 patients	105 implants	1: Osseospeed, Astratech Dental, Sweden 2. Prevail, Biomet 3i, USA	1: 6° 2:-	Internal polygonal butt-joint Cone morse	Clinical and radiographical assessment Marginal bone loss	__
Pariente L. [150]	J. Oral Implantol.	2020	CT	33 patients	50 implants	NA	NA	Conometric	Clinical and radiographic assessment	__
Park H [77]	J. Periodontal Implant Sci.	2021	Retrospective study	12 patients	24 implants	NA	NA	Cone morse	Clinical and radiographic assessment	__
Penitente PA [102]	Clin. Ter.	2023	Retrospective study	319 patients	1227 implants	NA	NA	External hexagon Cone morse	Clinical and radiographic assessment
Pessoa RS [140]	Clin. Implant Dent. Relat. Res.	2017	RCT	12 patients	48 implants	UNITITEVR, SIN—Sistema de Implante, Sao Paulo, Brazil	16°	External hexagon Conometric	Clinical and radiographic assessment	__
Pieri F [65]	Int. J. Oral Maxillofac. Implants	2011	RCT	40 patients	40 implants	__	NA	Internal hexagon Cone morse	Clinical and radiographical assessmentMarginal bone loss	__
Radaelli MTB [135]	J. Periodontal Res.	2020	CT	33 patients	109 implants	Neodent, Curitiba, PR, Brazil	11.5°	Conometric	Clinical and radiographic assessment	__
Raj HK [134]	J. Contemp. Dent. Pract.	2022	CT	20 patients	20 implants	Nobel Biocare	12°	Conometric	Clinical and radiographical assessment	__
Romanos G [83]	Clin. Implant Dent. Relat. Res.	2016	Retrospective study	247 patients	634 implants	Ankylos^®, Dentsply Implants, Mannheim, Germany	5.7°	Cone morse	Clinical and radiographic assessment	__
Romanos GE [87]	Int. J. Oral Maxillofac. Implants	2011	Retrospective study	122 patients	488 implants	__	NA	Cone morse		__
Saglanmak A [101]	Quintessence Int.	2021	Retrospective study	__	44 implants	NA	NA	Cone morse	Clinical and radiographic assessment
Scarano A [63]	J. Periodontol.	2016	CT	15 patients	37 implants	NA	NA	Cone morse Internal hexagon	__	__
Sharma V [26]	J. Indian. Prosthodont. Soc.	2022	CT	10 patients	20 implants	NA	NA	Cone morse	Clinical and radiographical assessment	none
Simonpieri A [84]	Quintessence Int.	2017	Retrospective study	42 patients	334 implants	In-Kone Universal System, Global D	8°	Cone morse	Clinical and radiographic assessment	__
Smojver I [47]	Int. J. Mol. Sci.	2022	CT	__	100 implants	NA	NA	Cone morse	Clinical and radiographic assessment	__
Spinelli A [40]	Materials (Basel)	2023	Cohort prospective study	36 patients	41 implants	Tapered Tissue-level Laser-Lok, Biohorizons, Birmingham, AL, USA	NA	Cone morse	Clinical and radiographical assessment	__
Stacchi C [137]	Clin. Implant Dent. Relat. Res.	2023	RCT	102 implants	51 patients	NA	NA	Conometric	Clinical and radiographical assessment	__
Studenikin R [142]	Int. J. Dent.	2021	CT	15 patients	15 implants	Nobel Biocare	12°	Conometric
Sun Y [100]	Clin. Implant Dent. Relat. Res.	2023	RCT	19 patients	42 implants	NA	NA	Cone morse	Clinical and radiographic assessment
Szyszkowski A [58]	Implant Dent.	2019	CT	214 patients	540 implants	(a) Alpha-Bio Tec, Petach Tikwa, Israel (b) MIS Implant Technologies, Shlomi, Israel	1: NA 2: 12°	Conometric Internal hexagon	Clinical and radiographic assessment	__
Tallarico M [96]	Eur. J. Dent.	2022	Cohort prospective study	90 patients	243 implants	Osstem TSIII, Osstem Implant Co. Ltd., Seoul, South Korea	NA	Cone morse	Clinical and radiographic assessment	Four prostheses failed
Tetè G [49]	J. Biol. Regul. Homeost. Agents	2020	CT	__	-	NA	NA	Cone morse	Clinical and radiographic assessment	__
Thomé G [81]	Int. J. Oral. Maxillofac. Implants	2020	Retrospective study	101 patients	453 implants	Helix Acqua GM, Neodent	NA	Cone morse	Clinical and radiographic assessment	__
Toia M [116]	Clin. Oral Implants Res.	2022	RCT	50 patients	119 implants	OsseoSpeed Astra Tech Implant System	1: 6°	Cone morse	Clinical and radiographic assessment	(a) Screw loosening (2): [abutment level group (AL) (1); implant level group (IG) (1)] (b) Screw fracture (2): [abutment level group (AL)]
van Hooft J [46]	J. Clin. Med.	2022	CT	16 patients	23 implants	NA	NA	Cone morse	Clinical and radiographic assessment	__
Vervaeke S [50]	J. Clin. Periodontol.	2018	CT	25 patients	52 implants	Astra Tech Osseospeed TX™, Denstply implants, USA	NA	Cone morse	Clinical and radiographic assessment	__
Weigl P [99]	J. Prosthet. Dent.	2019	CT	23 patients	91 implants	Ankylos	5.7°	Cone morse
Yamada S [27]	Int. J. Implant Dent.	2023	CT	31 patients	45 implants	1: NobelActive^®/NobelReplace Tapered 2: CC^®, Nobel Biocare, Gothenberg, Sweden, 3: Bone Level Implant^®/Bone Level Tapered Implant^®, Straumann, Basel, Switzerland	1: 6° 2: 11° 3: 15°	Cone morse Conometric	Clinical and radiographic assessment	none
Yang F [32]	Clin. Implant Dent. Relat. Res.	2022	Retrospective study	495 patients	945 implants	Ankylos; Dentsply Sirona	5.7°	Cone morse	Clinical and radiographic assessment	Abutment fracture (AF) (13) Abutment screw loosening (ASL) (12)
Yi Y [21]	J. Prosthet. Dent.	2023	Retrospective study	428 patients	898 implants	One-plant FIT; Warantec	1.5°	Cone morse	Clinical and radiographic assessment	Screw fractures (23) Screw loosening (417) Abutment fracture (102) Implant fracture (31)
Frisch E [103]	Clin. Implant. Dent. Relat. Res.	2015	Retrospective study	20 patients	80 implants	Ankylos, Dentsply Friadent, Mannheim, Germany)	5.7°	Cone morse	Clinical and radiographic assessment	__
Ho DS [104]	Clin. Oral. Implants Res.	2013	RCT	32 subjects	64 implants	Test: NobelActive™ Control: Brånemark	1: 6° 2:NA	Cone morse	Clinical and radiographic assessment	__
Mangano F [105]	Clin. Oral Implants Res.	2012	Retrospective study	26 patients	26 implants	Leone Implant System(R), Florence, Italy	NA	Cone morse	Clinical and radiographic assessment	__
Bae MS [144]	Implant Dent.	2011	Retrospective study	92 patients	294 implants	MIS Implants Technologies Ltd., Shlomi, Israel	12°	Conometric	Clinical and radiographic assessment
Mangano C [106]	Clin. Oral Implants Res.	2011	CT	60 patients	288 implants	Leone Implant System (^®)	NA	Cone morse	Clinical and radiographic assessment	__
Mangano C [107]	J. Periodontal.	2011	CT	893 patients	2.549 implants	NA	NA	Cone morse	Clinical and radiographic assessment	Few prosthetic complications at the implant–abutment interface reported (0.37%)
Moberg LE [108]	Clin. Oral Implants Res.	1999	CT	29 patients	30 implants	ITI implant system	NA	Cone morse Internal octagonal butt-joint	Clinical and radiographic assessment	__
Palmer RM [145]	Clin. Oral Implants Res.	1997	CT	15 patients	15 implants	AstraTech, Molndal Sweden	1: 11.2°	Conometric	Clinical and radiographic assessment	- 1 crown recemented after 18 months - 1 crown replaced due to fracturing of the porcelain
Levine RA [109]	Int. J. Oral Maxillofac. Implants	1997	CT	129 patients	174 implants	ITI implant system	NA	Cone morse	Clinical and radiographic assessment	- Occlusal screw loosening (8.7%) - Solid conical abutment loosening had a 3.6% occurrence rate
Chapman RJ [110]	Implant Dent.	1996	CT	__	1.757 implants	NA	NA	Cone morse	__	9 abutment posts fractured for a failure rate of 0.05%. 31 (1.7%) abutments loosened.
Morris HF [111]	J. Oral. Implantol.	2001	CT	313 patients	1.419 implants	Ankylos Implant	5.7°	Cone morse	Clinical and radiographic assessment	__
Mangano C [112]	Int. J. Oral Maxillofac. Implants	2001	Retrospective study	69 patients	80 implants	Mac System, Cabon, Milan, Italy	NA	Cone morse	Clinical and radiographic assessment	2 fractured abutments and 1 loosened abutment
Gatti C [113]	Clin. Implant Dent. Relat. Res.	2002	CT	10 patients	40 implants	Brånemark implants (MK II; Nobel Biocare AB, Gothenburg, Sweden) Nobel Biocare AB	NA	Cone morse	__	__
Kronström M [114]	J. Prosthet. Dent.	2003	CT	17 patients	68 implants	Brånemark implants	NA	Cone Morse
Chou CT [115]	J. Oral Implantol.	2004	CT	__	1500 implants	Ankylos Implant	5.7°	Cone morse	Clinical and radiographic assessment	__
Toia M. [116]	Clin. Oral Implants Res.	2023	RCT	50 patients	119 implants	NA	NA	Cone morse	Clinical and radiographic assessment	__
Galindo-Moreno P [117]	J. Clin. Med.	2023	Retrospective study	-	-	NA	NA
Gehrke SA [118]	Medicina (Kaunas)	2023	Retrospective study	79 patients	120 implants	NA	NA	Cone morse		C. group: fractured abutments (5%), no abutment loosening T. group: no abutment fracture, loosening screws (11.3%)
Gehrke SA [95]	J. Funct. Biomater.	2023	Retrospective study	65 patients	26 implants	NA	NA	Cone morse		One patient failed due to an abutment fracture after 25 months of function
Lops D. [119]	J. Clin. Med.	2022	Retrospective study	80 patients	312 implants	Anyridge; MegaGen Implant	5°	Cone morse	Clinical and radiographic assessment	-
Galindo-Moreno P [149]	Clin. Oral Implants Res.	2022	Retrospective study	19 patients	160 implants	OsseoSpeed Astra Tech TX implants	6°	Cone morse	Clinical and radiographic assessment	14 implants > 2 mm of MBL (8.75%)
Mangalvedhekar M [120]	J. Pharm. Bioallied. Sci.	2022	CT	50 patients	50 implants	1: Nobel Biocare 2: Nobel Biocare	1: 6° 2: NA	Cone morse External hexagon (EH)	Clinical and radiographic assessment	__
Pozzi A [146]	Int. J. Periodontics Restorative Dent.	2021	Retrospective study	281 patients	686 implants	NA	NA	Conometric	__
Eskan MA [147]	Int. J. Implant Dent.	2020	Retrospective study	42 patients	171 implants	Straumann	11.5°	Conometric	Clinical and radiographic assessment	__
Friberg B [121]	Clin. Implant Dent. Relat. Res.	2019	CT	47 patients	51 implants	NobelParallel CC	6°	Cone morse	Clinical and radiographic assessment	__
Mundt T [122]	Int. J. Oral Maxillofac. Implants	2006	Retrospective study	159 patients	663 implants	1:Ankylos Implant 2: Branemark Systems 3: NP MkIII Ti Unite 4: Frialit CELLplust 5: Replaces 6: Select Tapered Ti Unite 7: XiVE S CELL 8: Osseotite XPt 9: Straumann	1: 5.7° 2: NA 3: NA 4: NA 5: 6° 6:6° 7: NA 8: 11.5°	Cone morse Conometric Internal hexagonal External hexagonal	Clinical and radiographic assessment	__
Mangano C [123]	Eur. J. Oral Implantol.	2008	CT	302 patients	314 implants	NA	NA	Cone morse	Clinical and radiographic assessment	0.6% implant–abutment loosening rate
Mangano C [124]	Clin. Oral Implants Res.	2009	CT	689 patients	1920 implants	Leone Implant System, Florence, Italy	NA	Cone morse	Clinical and radiographic assessment	0.65% rate of loosening at the implant–abutment interface
Mangano C [125]	Int. J. Oral. Maxillofac. Implants	2010	CT	295 patients	307 implants	NA	NA	Cone morse	Clinical and radiographic assessment	__
Gultekin BA [126]	Int. J. Oral Maxillofac. Implants	2013	CT	25 patients	93 implants	Ti UNITE, Nobel Biocare	6°	Cone morse	Clinical and radiographic assessment	__
Pozzi A [127]	Clin. Implant Dent. Relat. Res.	2014	RCT	34 patients	68 implants	1: NobelActive, Nobel Biocare AB, Göteborg, Sweden 2: Nobel Speedy Groovy, Nobel Biocare AB, Sweden	1: 6° 2: 6°	External hexagon Cone morse	Clinical and radiographic assessment	__
Pozzi A [128]	Eur. J. Oral Implantol.	2015	CT	54 patients	118 implants	Nobel Replace Conical Connection implants, Nobel Biocare, Swiss	6°	Cone morse	Clinical and radiographic assessment	Crown failure (1)

3.4. Risk of Bias Assessment (RoB)

The RoB is reported in Figure 2 and Figure 3. The randomization bias [50.00% wlr; 28.34% ur; 41.66% whr], selection bias [100% wlr; -% ur; -% whr], performance bias [25.03% wlr; 36.82% ur; 16.66% whr], detection bias [50.02% wlr; 24.99% ur; 24.99% whr], attrition bias [100% wlr; -% ur; -% who], reporting bias [100% wlr; -% ur; -% whr], and other biases [100% wlr; -% ur; -% whr] are reported. A total of five studies reported a low risk of bias.

Figure 2. Risk of bias graph: cumulative assessment of each risk of bias item presented as percentages across all included studies.

Figure 3. Risk of bias graph: cumulative assessment of each risk of bias for each study considered.

3.5. Meta-Analysis

A higher surface under the cumulative ranking curve (SUCRA) indicates better performance of the study groups. The SUCRA plot represents the residual deviance for the network meta-analysis, indicating the consistency on the x-axis and the unrelated mean effect inconsistency models on the y-axis. On other hand, the radial SUCRA plot showed higher values, indicating better treatments, while the node sizes represent the sample size in terms of the number of participants. The thickness of the lines indicates the number of trials screened. At the baseline, no significant difference in marginal bone resorption is detected when comparing the cone morse group (CM) with the conometric joint design group (p > 0.05) [MD:−0.20; 95%CI:−0.15; 0.55]. The forest plot a significantly higher marginal bone loss at the baseline when comparing the EH and CM groups [MD: 0.38. 95%CI: 0.13, 0.62] and in the HI group compared to the CM group [MD: 0.64. 95%CI: 0.27, 1.02] (p < 0.05). A significant difference in marginal bone loss was detected when comparing the EH and conometric joint groups [MD: 0.183; 95% CI:−0.527, 0.899] (p < 0.05) and the HI and conometric implant groups [MD: 0.47; 95% CI:−0.00484, 0.956].

3.6. Meta-Regression MBL

The forest plot reporting the relative effects emerged from random effect assessment is reported in Figure 4, Figure 5, Figure 6 and Figure 7.

Figure 4. Chart summarizing the Litmus Rank-O-Gram and radial chart: surface under the cumulative ranking curve (SUCRA) values and cumulative ranking curves are indicative of higher clinical performance.

Figure 5. Network meta-analysis summarizing the comparative performance and the interactions between the groups.

Figure 6. Forest plot summarizing the comparative performance and the interactions between the groups.

Figure 7. Forest plot summarizing the direct comparative performance between the groups.

4. Discussion

This study was conducted to analyze the geometric characteristics of the implant–abutment connection, their effects on the long-term stability of the connection, and the marginal bone loss of the conical interface joint. In the first instance, the major limitation of the present review is represented by the risk of bias of the articles included which, in most cases, described a non-randomized study model design. This aspect could affect and significantly indicate the strength of a study’s effectiveness. Long-term peri-implant stability under loading represents a critical factor when evaluating implants under functional conditions. This aspect is determinant, especially considering the epidemiological consistency of peri-implant-related disease, which represents the most frequent non-disease-free survival condition, with a prevalence of >50% for mucositis and peri-implantitis [151]. The microleakage of the implant–abutment interface occurs in all implant systems, with variability between systems [152]. Cone morse joints with an 8° internal angle in implant dentistry were first proposed by the ITI group [93] in order to provide a more stable mechanical coupling of the implant–abutment interface [153]. Today, other manufacturers use cone morse designs with different cone angles. However, comparative evaluations of the clinical performance of implants with different conical angles are rare in the literature. The NMA approach could represent an optional approach able to overcome these limits offering the possibility to evaluate the marginal bone loss obtained from different studies. Considering the wide range of variability of the study designs and methodologies, the present analysis considered only one experimental time 6 months after the loading in order to avoid the risk of indirectness bias. The main advantage of the increased mechanical stability of the implant/abutment coupling is the reduction in the micro-gap and microleakage at the interface [63]. Morse taper connections have proven to be more stable from a biomechanical point of view [154,155]. The main advantage of the conical interface with or without a geometrical index is determined by the cone-in-cone principle, where the joint stability is consistently increased by the abutment’s lateral contact with the internal chamber walls.

Different types of implant connections were evaluated in this review, considering a cone angle cut off >8° to be a conometric joint and a cone morse with a joint angle <8° to have an external and internal hexagon. The purpose of this review was to investigate marginal bone loss and the mechanical complications related to dynamic function [93]. The main findings were that conical connections seem to provide a better reduction in mechanical complications and a lower incidence of marginal bone loss compared to internal and external implant–abutment designs. On the other hand, no significant difference in marginal bone loss has been reported when comparing both of the conical implant joints. The higher mechanical stability of conical joint profile seems to support the hypothesis of its influence on the maintenance of peri-implant health. Several studies reported that the formation of micro-gaps could be correlated with the micromovements generated during masticatory loading, with the forces producing possible biological and mechanical sequelae [152]. Biologically, the bacteria infiltration could represent a critical factor, and the cone morse design seems to reduce the risk of interface penetration at the level of the joint interface [154,155]. The biological response associated with the two types of connections was also evaluated, and it turns out that the biological response is the same, although differences may occur when evaluating the mechanical part. The taper connection is, therefore, analyzed both in the evaluation of the marginal micro-gap with consequent bacterial proliferation in situ, and from the point of view of tissue biology and biomechanics [156]. As previously descripted, the interface micro-gap between the implant and the prosthetic abutment is related to biological and mechanical implications [63]. In vitro studies documented that bacterial penetration has been detected in static conditions and could increase under the loading, producing an inflammatory cell infiltrate (infiltrated connective tissue [ICT]) [157]. On other hand, this crestal sufferance is not visible in sleeping implants, and the reason for this is not completely clarified [157]. As such. the bacterial and mechanical factors are currently considered to be the presumed risk factors for this purpose [158]. The implant’s functional connection is determinant and could be presumed to be the trigger step where the cone morse joint demonstrates a superior effectiveness in terms of marginal bone stability. Regarding the micro-gap, it could create an unfavorable distribution of the mechanical loading and stresses on the implant–abutment interface, producing mechanical issues. A previous study reported that the length of the implant–abutment joint is a key factor that produces differences in terms of bacterial penetration. This particular aspect was not investigated in the present study due to there being very little information available publicly in accordance with the patent specifications of the implant devices that were considered; this could be considered a future perspective for novel studies. It is clear from the literature that the interface space generated between the abutment and the implant joint can produce a niche that could favor bacterial penetration, compromising the peri-implant tissue seal [159]. Another aspect to be evaluated are possible prosthetic complications that may occur [160]. The major complications reported in the present review were crown loosening, ceramic chipping, abutment/fixation screw loosening and fracture, and implant loss [45,145]. The biological response between the two types of conical connections appeared similar, lacking the mechanical response, which is, however, superior to the internal and external hexagon. On other hand, other mechanical factors could contribute to the mechanical behavior of conical connections, including the abutment walls’ contact length, the screw pitch and length, the implant chamber volume, and the presence/absence of a connection index. This could be considered as a significant limit of the present comparison. In addition, the present investigation did not separately consider tilted and straight implants. In fact, the biomechanics could also contribute significantly to the medium- and long-term complications, both biologically and prosthetically. Also, the methodological differences could be considered as a potential flaw, including differences in insertion torque, implant–abutment fixation coupling torque, prosthetic finalization protocols, and, consequently, the number of interventions on the fixation screw.

These aspects should be considered separately for future pairwise comparisons considering large sample size studies and randomized clinical trials.

5. Conclusions

Within the limits of the present systematic review, the marginal resorption evidence suggests that the implant abutment design seems to influence the peri-implant health and the maintenance of the bone levels in the short-term. The conical joint design seems to provide more efficient stabilization of the marginal bone compared to the internal and external hexagon designs. No significant differences were detected in marginal bone stability when comparing different cone angles. Differences in methodology and follow-up times did not allow a pairwise effectiveness evaluation to be conducted in the medium- and long-term.

Author Contributions

Conceptualization, I.A., A.S., B.S. and F.L.; software, I.A. and F.L.; validation, I.A., A.S., B.S., E.X. and F.L.; formal analysis, I.A., A.S., B.S., E.X. and F.L.; investigation, I.A., A.S., B.S., E.X. and F.L.; data curation, I.A., A.S., B.S., E.X. and F.L.; writing—original draft preparation, I.A., A.S., B.S., E.X. and F.L.; writing—review and editing, I.A., A.S., B.S., E.X. and F.L. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

All experimental data to support the findings of this study are available by contacting the corresponding author upon request. The authors have annotated the entire data building process and the empirical techniques presented in the paper.

Conflicts of Interest

The authors declare no conflicts of interest.

References

Albrektsson, T.; Zarb, G.; Worthington, P.; Eriksson, A.R. The Long-Term Efficacy of Currently Used Dental Implants: A Review and Proposed Criteria of Success. Int. J. Oral Maxillofac. Implants 1986, 1, 11–25. [Google Scholar] [PubMed]
Hamada, Y.; Shin, D.; John, V. Peri-Implant Disease—A Significant Complication of Dental Implant Supported Restorative Treatment. J. Indiana Dent. Assoc. 2016, 95, 31–38. [Google Scholar] [PubMed]
Koutouzis, T. Implant-abutment Connection as Contributing Factor to Peri-implant Diseases. Periodontol. 2000 2019, 81, 152–166. [Google Scholar] [CrossRef] [PubMed]
Comuzzi, L.; Tumedei, M.; Romasco, T.; Petrini, M.; Afrashtehfar, K.I.; Inchingolo, F.; Piattelli, A.; Di Pietro, N. Insertion Torque, Removal Torque, and Resonance Frequency Analysis Values of Ultrashort, Short, and Standard Dental Implants: An In Vitro Study on Polyurethane Foam Sheets. J. Funct. Biomater. 2023, 14, 10. [Google Scholar] [CrossRef]
King, G.N.; Hermann, J.S.; Schoolfield, J.D.; Buser, D.; Cochran, D.L. Influence of the Size of the Microgap on Crestal Bone Levels in Non-Submerged Dental Implants: A Radiographic Study in the Canine Mandible. J. Periodontol. 2002, 73, 1111–1117. [Google Scholar] [CrossRef]
Daher, F.I.; Abi-Aad, H.L.; Dimassi, H.I.; Cordioli, G.; Majzoub, Z.A.K. Immediate versus Conventional Loading of Variable-Thread Tapered Implants Supporting Three- to Four-Unit Fixed Partial Dentures in the Posterior Maxilla: 3-Year Results of a Split-Mouth Randomised Controlled Trial. Int. J. Oral Implantol. 2019, 12, 449–466. [Google Scholar]
Bernardes, S.R.; da Gloria Chiarello de Mattos, M.; Hobkirk, J.; Ribeiro, R.F. Loss of Preload in Screwed Implant Joints as a Function of Time and Tightening/Untightening Sequences. Int. J. Oral Maxillofac. Implants 2014, 29, 89–96. [Google Scholar] [CrossRef]
Liu, Y.; Wang, J. Influences of Microgap and Micromotion of Implant–Abutment Interface on Marginal Bone Loss around Implant Neck. Arch. Oral Biol. 2017, 83, 153–160. [Google Scholar] [CrossRef]
Romeo, E.; Ghisolfi, M.; Murgolo, N.; Chiapasco, M.; Lops, D.; Vogel, G. Therapy of Peri-Implantitis with Resective Surgery: A 3-Year Clinical Trial on Rough Screw-Shaped Oral Implants. Part I: Clinical Outcome. Clin. Oral Implants Res. 2004, 16, 9–18. [Google Scholar] [CrossRef]
Kim, D.-H.; Kim, H.J.; Kim, S.; Koo, K.-T.; Kim, T.-I.; Seol, Y.-J.; Lee, Y.-M.; Ku, Y.; Rhyu, I.-C. Comparison of Marginal Bone Loss between Internal- and External-Connection Dental Implants in Posterior Areas without Periodontal or Peri-Implant Disease. J. Periodontal Implant Sci. 2018, 48, 103–113. [Google Scholar] [CrossRef]
Ellakany, P.; Mahrous, A.; Eraky, D.; Albarrak, A.; AlJindan, R.; Fouda, S. Evaluation of Bacterial Leakage in Platform-Switching Dental Implant with Morse Taper Connection Under Thermocycling and Loading Effects: In Vitro Study. Int. J. Oral Maxillofac. Implants 2021, 36, 68–74. [Google Scholar] [CrossRef] [PubMed]
Assenza, B.; Tripodi, D.; Scarano, A.; Perrotti, V.; Piattelli, A.; Iezzi, G.; D’Ercole, S. Bacterial Leakage in Implants with Different Implant-Abutment Connections: An in Vitro Study. J. Periodontol. 2012, 83, 491–497. [Google Scholar] [CrossRef] [PubMed]
Fernandes, P.F.; Grenho, L.; Fernandes, M.H.; Sampaio-Fernandes, J.C.; Gomes, P.S. Microgap and Bacterial Microleakage during the Osseointegration Period: An in Vitro Assessment of the Cover Screw and Healing Abutment in a Platform-Switched Implant System. J. Prosthet. Dent. 2023, 130, 87–95. [Google Scholar] [CrossRef] [PubMed]
Larrucea, C.; Conrado, A.; Olivares, D.; Padilla, C.; Barrera, A.; Lobos, O. Bacterial Microleakage at the Abutment-Implant Interface, in Vitro Study. Clin. Implant Dent. Relat. Res. 2018, 20, 360–367. [Google Scholar] [CrossRef]
Sahin, C.; Ayyildiz, S. Correlation between Microleakage and Screw Loosening at Implant-Abutment Connection. J. Adv. Prosthodont. 2014, 6, 35. [Google Scholar] [CrossRef]
Norton, M.R. An in Vitro Evaluation of the Strength of an Internal Conical Interface Compared to a Butt Joint Interface in Implant Design. Clin. Oral Implants Res. 1997, 8, 290–298. [Google Scholar] [CrossRef]
Ohat, N. Handbook for Conducting a Literature-Based Health Assessment Using OHAT Approach for Systematic Review and Evidence Integration; US Department of Health and Human Services: Washington, DC, USA, 2019. [Google Scholar]
Owen, R.K.; Bradbury, N.; Xin, Y.; Cooper, N.; Sutton, A. MetaInsight: An Interactive Web-Based Tool for Analyzing, Interrogating, and Visualizing Network Meta-Analyses Using R-Shiny and Netmeta. Res. Synth. Methods 2019, 10, 569–581. [Google Scholar] [CrossRef]
Hutton, B.; Salanti, G.; Caldwell, D.M.; Chaimani, A.; Schmid, C.H.; Cameron, C.; Ioannidis, J.P.A.; Straus, S.; Thorlund, K.; Jansen, J.P.; et al. The PRISMA Extension Statement for Reporting of Systematic Reviews Incorporating Network Meta-Analyses of Health Care Interventions: Checklist and Explanations. Ann. Intern. Med. 2015, 162, 777–784. [Google Scholar] [CrossRef]
Cannata, M.; Grandi, T.; Samarani, R.; Svezia, L.; Grandi, G. A Comparison of Two Implants with Conical vs. Internal Hex Connections: 1-Year Post-Loading Results from a Multicentre, Randomised Controlled Trial. Eur. J. Oral Implantol. 2017, 10, 161–168. [Google Scholar]
Yi, Y.; Heo, S.J.; Koak, J.Y.; Kim, S.K. Mechanical Complications of Implant-Supported Restorations with Internal Conical Connection Implants: A 14-Year Retrospective Study. J. Prosthet. Dent. 2023, 129, 732–740. [Google Scholar] [CrossRef]
Moergel, M.; Rocha, S.; Messias, A.; Nicolau, P.; Guerra, F.; Wagner, W. Clinical and Radiographic Performance of Self-Locking Conical Connection Implants in the Posterior Mandible: Five-Year Results of a Two-Centre Prospective Study. Clin. Oral Implants Res. 2021, 32, 998–1007. [Google Scholar] [CrossRef] [PubMed]
Degidi, M.; Nardi, D.; Gianluca, S.; Piattelli, A. The Conometric Concept: A 5-Year Follow-up of Fixed Partial Monolithic Zirconia Restorations Supported by Cone-in-Cone Abutments. Int. J. Periodontics Restor. Dent. 2018, 38, 363–371. [Google Scholar] [CrossRef] [PubMed]
Mangano, F.; Margiani, B.; Admakin, O. A Novel Full-Digital Protocol (SCAN-PLAN-MAKE-DONE(^®)) for the Design and Fabrication of Implant-Supported Monolithic Translucent Zirconia Crowns Cemented on Customized Hybrid Abutments: A Retrospective Clinical Study on 25 Patients. Int. J. Environ. Res. Public Health 2019, 16, 317. [Google Scholar] [CrossRef] [PubMed]
Obreja, K.; Begić, A.; Trimpou, G.; Galarraga-Vinueza, M.E.; Balaban, Ü.; Schwarz, F.; Parvini, P. Clinical and Esthetic Evaluation Following Immediate Implant Placement and Restoration with Platform- Switched Morse Taper Implants in the Esthetic Zone: A Cross-Sectional Study. Int. J. Periodontics Restor. Dent. 2022, 42, 665–673. [Google Scholar] [CrossRef]
Sharma, V.; Paliwal, J.; Bhansali, S.; Meena, K.K.; Gupta, N.; Dadarwal, A. Evaluation of Clinical and Radiographic Outcome of Friction Fit Conical Abutment System in Implant-Supported Dental Prostheses: An in Vivo Study. J. Indian Prosthodont. Soc. 2022, 22, 29–37. [Google Scholar] [CrossRef]
Yamada, S.; Nakano, T.; Kobayashi, T.; Ishigaki, S. Maxillary Labial Peri-Implant Hard and Soft Tissue Alteration Observed on Cross-Sectional Dimension: A 2-Year Prospective Observational Study. Int. J. Implant Dent. 2023, 9, 16. [Google Scholar] [CrossRef]
Jin, X.; Guan, Y.; Ren, J.; Zhao, Y.; Wang, X.; He, F. A Retrospective Study of 12,538 Internal Conical Connection Implants Focused on the Long-Term Integrity of Implant-Abutment Complexes. Clin. Oral Implants Res. 2022, 33, 377–390. [Google Scholar] [CrossRef]
Ackermann, K.-L.; Barth, T.; Cacaci, C.; Kistler, S.; Schlee, M.; Stiller, M. Clinical and Patient-Reported Outcome of Implant Restorations with Internal Conical Connection in Daily Dental Practices: Prospective Observational Multicenter Trial with up to 7-Year Follow-Up. Int. J. Implant Dent. 2020, 6, 14. [Google Scholar] [CrossRef]
Fabbri, G.; Fradeani, M.; Dellificorelli, G.; De Lorenzi, M.; Zarone, F.; Sorrentino, R. Clinical Evaluation of the Influence of Connection Type and Restoration Height on the Reliability of Zirconia Abutments: A Retrospective Study on 965 Abutments with a Mean 6-Year Follow-Up. Int. J. Periodontics Restor. Dent. 2017, 37, 19–31. [Google Scholar] [CrossRef]
Sánchez-Torres, A.; Cercadillo-Ibarguren, I.; Figueiredo, R.; Gay-Escoda, C.; Valmaseda-Castellón, E. Mechanical Complications of Implant-Supported Complete-Arch Restorations and Impact on Patient Quality of Life: A Retrospective Cohort Study. J. Prosthet. Dent. 2021, 125, 279–286. [Google Scholar] [CrossRef]
Yang, F.; Ruan, Y.; Liu, Y.; Chen, J.; Chen, Y.; Zhang, W.; Ding, Y.; Wang, L. Abutment Mechanical Complications of a Morse Taper Connection Implant System: A 1- to 9-Year Retrospective Study. Clin. Implant Dent. Relat. Res. 2022, 24, 683–695. [Google Scholar] [CrossRef] [PubMed]
Toia, M.; Stocchero, M.; Galli, S.; Papia, E.; Wennerberg, A.; Becktor, J.P. The Use of Implant-Level Connection in Screw-Retained Fixed Partial Dentures: A 3-Year Randomised Clinical Trial. Clin. Oral Implants Res. 2022, 33, 78–93. [Google Scholar] [CrossRef] [PubMed]
Cassetta, M.; Di Mambro, A.; Giansanti, M.; Brandetti, G.; Calasso, S. A 36-Month Follow-up Prospective Cohort Study on Peri-Implant Bone Loss of Morse Taper Connection Implants with Platform Switching. J. Oral Sci. 2016, 58, 49–57. [Google Scholar] [CrossRef] [PubMed][Green Version]
Degidi, M.; Nardi, D.; Sighinolfi, G.; Piattelli, A. The Conometric Concept: Definitive Fixed Lithium Disilicate Restorations Supported by Conical Abutments. J. Prosthodont. 2018, 27, 605–610. [Google Scholar] [CrossRef]
Eerdekens, L.; Schols, M.; Coelst, L.; Quirynen, M.; Naert, I. A 5-Year Prospective Study on Cone-Anchored Implants in the Edentulous Maxilla. Clin. Implant Dent. Relat. Res. 2015, 17 (Suppl. S2), e621–e632. [Google Scholar] [CrossRef]
Naumann, M.; Scholz, P.; Krois, J.; Schwendicke, F.; Sterzenbach, G.; Happe, A. Monolithic Hybrid Abutment Crowns (Screw-Retained) versus Monolithic Hybrid Abutments with Adhesively Cemented Monolithic Crowns. Clin. Oral Implants Res. 2023, 34, 209–220. [Google Scholar] [CrossRef]
Cassetta, M.; Driver, A.; Brandetti, G.; Calasso, S. Peri-Implant Bone Loss around Platform-Switched Morse Taper Connection Implants: A Prospective 60-Month Follow-up Study. Int. J. Oral Maxillofac. Surg. 2016, 45, 1577–1585. [Google Scholar] [CrossRef]
Oda, Y.; Mori, G.; Honma, S.; Ito, T.; Iijima, T.; Yajima, Y. Marginal Bone Loss and the Risk Indicators of Fixed Screw-Retained Implant-Supported Prostheses and Fixed Telescopic-Retained Implant-Supported Prostheses in Full Arch: A Retrospective Case-Control Study. Clin. Oral Implants Res. 2021, 32, 818–827. [Google Scholar] [CrossRef]
Spinelli, A.; Zamparini, F.; Romanos, G.; Gandolfi, M.G.; Prati, C. Tissue-Level Laser-Lok Implants Placed with a Flapless Technique: A 4-Year Clinical Study. Materials 2023, 16, 1293. [Google Scholar] [CrossRef]
Sato, R.K.; Thomé, G.; Fontão, F.N.G.K.; de Melo Filho, A.; Melo, A.C.M. Morse Taper Implants Immediately Loaded in Fresh Extraction Sockets: A Prospective Cohort Study. Implant Dent. 2017, 26, 345–350. [Google Scholar] [CrossRef]
Baer, R.A.; Nölken, R.; Colic, S.; Heydecke, G.; Mirzakhanian, C.; Behneke, A.; Behneke, N.; Gottesman, E.; Ottria, L.; Pozzi, A.; et al. Immediately Provisionalized Tapered Conical Connection Implants for Single-Tooth Restorations in the Maxillary Esthetic Zone: A 5-Year Prospective Single-Cohort Multicenter Analysis. Clin. Oral Investig. 2022, 26, 3593–3604. [Google Scholar] [CrossRef] [PubMed]
Degidi, M.; Daprile, G.; Piattelli, A. Marginal Bone Loss around Implants with Platform-Switched Morse-Cone Connection: A Radiographic Cross-Sectional Study. Clin. Oral Implants Res. 2017, 28, 1108–1112. [Google Scholar] [CrossRef] [PubMed]
Ghensi, P.; Tonetto, G.; Soldini, C.; Bettio, E.; Mortellaro, C.; Soldini, C. Dental Implants With a Platform-Switched Morse Taper Connection and an Osteo Growth Induction Surface. J. Craniofacial Surg. 2019, 30, 1049–1054. [Google Scholar] [CrossRef] [PubMed]
Cacaci, C.; Ackermann, K.-L.; Barth, T.; Kistler, S.; Stiller, M.; Schlee, M. A Non-Interventional Multicenter Study to Document the Implants Success and Survival Rates in Daily Dental Practices of the CONELOG Screw-Line Implant. Clin. Oral Investig. 2019, 23, 2609–2616. [Google Scholar] [CrossRef] [PubMed]
van Hooft, J.; Kielenstijn, G.; Liebregts, J.; Baan, F.; Meijer, G.; D’haese, J.; Bronkhorst, E.; Verhamme, L. Intraoral Scanning as an Alternative to Evaluate the Accuracy of Dental Implant Placements in Partially Edentate Situations: A Prospective Clinical Case Series. J. Clin. Med. 2022, 11, 5876. [Google Scholar] [CrossRef]
Smojver, I.; Bjelica, R.; Vuletić, M.; Gerbl, D.; Budimir, A.; Gabrić, D. Antimicrobial Efficacy and Permeability of Various Sealing Materials in Two Different Types of Implant–Abutment Connections. Int. J. Mol. Sci. 2022, 23, 8031. [Google Scholar] [CrossRef]
Do Vale Souza, J.P.; de Moraes Melo Neto, C.L.; Piacenza, L.T.; Freitas da Silva, E.V.; de Melo Moreno, A.L.; Penitente, P.A.; Brunetto, J.L.; Dos Santos, D.M.; Goiato, M.C. Relation Between Insertion Torque and Implant Stability Quotient: A Clinical Study. Eur. J. Dent. 2021, 15, 618–623. [Google Scholar] [CrossRef]
Tetè, G.; Cisternino, L.; Giorgio, G.; Sacchi, L.; Montemezzi, P.; Sannino, G. Immediate versus Delayed Loading of Post-Extraction Implants in the Aesthetic Zone: A Prospective Longitudinal Study with 4-Year Follow-Up. J. Biol. Regul. Homeost. Agents 2020, 34, 19–25. [Google Scholar]
Vervaeke, S.; Matthys, C.; Nassar, R.; Christiaens, V.; Cosyn, J.; De Bruyn, H. Adapting the Vertical Position of Implants with a Conical Connection in Relation to Soft Tissue Thickness Prevents Early Implant Surface Exposure: A 2-Year Prospective Intra-Subject Comparison. J. Clin. Periodontol. 2018, 45, 605–612. [Google Scholar] [CrossRef]
Heydecke, G.; Mirzakhanian, C.; Behneke, A.; Behneke, N.; Fügl, A.; Zechner, W.; Baer, R.A.; Nölken, R.; Gottesman, E.; Colic, S.; et al. A Prospective Multicenter Evaluation of Immediately Functionalized Tapered Conical Connection Implants for Single Restorations in Maxillary Anterior and Premolar Sites: 3-Year Results. Clin. Oral Investig. 2019, 23, 1877–1885. [Google Scholar] [CrossRef]
Fernández-Figares-Conde, I.; Castellanos-Cosano, L.; Fernandez-Ruiz, J.-A.; Soriano-Santamaria, I.; Hueto-Madrid, J.-A.; Gómez-Lagunas, J.; Romano-Laureato, R.; Torres-Lagares, D. Multicentre Prospective Study Analysing Relevant Factors Related to Marginal Bone Loss: A Two-Year Evolution. Dent. J. 2023, 11, 185. [Google Scholar] [CrossRef] [PubMed]
Hamudi, N.; Barnea, E.; Weinberg, E.; Laviv, A.; Mijiritsky, E.; Matalon, S.; Chaushu, L.; Kolerman, R. The Association of the One-Abutment at One-Time Concept with Marginal Bone Loss around the SLA and Platform Switch and Conical Abutment Implants. J. Clin. Med. 2021, 11, 74. [Google Scholar] [CrossRef] [PubMed]
Canullo, L.; Pesce, P.; Tronchi, M.; Fiorellini, J.; Amari, Y.; Penarrocha, D. Marginal Soft Tissue Stability around Conical Abutments Inserted with the One Abutment-One Time Protocol after 5 Years of Prosthetic Loading. Clin. Implant Dent. Relat. Res. 2018, 20, 976–982. [Google Scholar] [CrossRef] [PubMed]
Mangano, F.; Lucchina, A.G.; Brucoli, M.; Migliario, M.; Mortellaro, C.; Mangano, C. Prosthetic Complications Affecting Single-Tooth Morse-Taper Connection Implants. J. Craniofacial Surg. 2018, 29, 2255–2262. [Google Scholar] [CrossRef] [PubMed]
De Melo, L.A.; de Farias, D.B.; de Medeiros, A.K.B.; Barbosa, G.A.S.; Dantas, E.M.; Carreiro, A. da F.P. Comparative Evaluation of Peri-Implant Tissues in Patients Wearing Mandibular Overdenture with Different Implant Platforms. J. Indian Soc. Periodontol. 2017, 21, 473–477. [Google Scholar] [CrossRef]
Melo, L.A.d.; de Souza, M.B.C.; Barbosa, G.A.S.; Carreiro, A. da F.P. Peri-Implant Bone Loss of External Hexagon and Morse Taper in Patients Wearing Immediately Loaded Overdentures. Braz. Dent. J. 2017, 28, 694–698. [Google Scholar] [CrossRef]
Szyszkowski, A.; Kozakiewicz, M. Effect of Implant-Abutment Connection Type on Bone Around Dental Implants in Long-Term Observation: Internal Cone Versus Internal Hex. Implant Dent. 2019, 28, 430–436. [Google Scholar] [CrossRef]
Horwitz, J.; Machtei, E.E.; Frankental, S.; Gabay, E.; Mayer, Y.; Joseph, L.; Cohen, O. Clinical and Patient-Related Outcomes of a Tapered Implant System With Switched Platform Conical Abutments: A Private Practice Field Trial. J. Oral Implantol. 2018, 44, 326–329. [Google Scholar] [CrossRef]
Dagher, M.; Mokbel, N.; Aboukhalil, R.; Ghosn, N.; Kassir, A.; Naaman, N. Marginal Bone Level and Bone Thickness Reduction in Delayed and Immediate Implant Placement Protocol 6 Months Post-Loading: An Observational Clinical Prospective Study. J. Maxillofac. Oral Surg. 2022, 21, 571–579. [Google Scholar] [CrossRef]
Degidi, M.; Nardi, D.; Piattelli, A. The Conometric Concept: Coupling Connection for Immediately Loaded Titanium-Reinforced Provisional Fixed Partial Dentures—A Case Series. Int. J. Periodontics Restor. Dent. 2016, 36, 347–354. [Google Scholar] [CrossRef]
De Paoli, S.; Benfenati, S.P.; Gobbato, L.; Toia, M.; Chen, C.-Y.; Nevins, M.; Kim, D.M. A Prospective Clinical Assessment of BioHorizons Tissue-Level Implants. Int. J. Periodontics Restor. Dent. 2023, 43, 105–111. [Google Scholar] [CrossRef] [PubMed]
Scarano, A.; Lorusso, C.; Di Giulio, C.; Mazzatenta, A. Evaluation of the Sealing Capability of the Implant Healing Screw by Using Real Time Volatile Organic Compounds Analysis: Internal Hexagon Versus Cone Morse. J. Periodontol. 2016, 87, 1492–1498. [Google Scholar] [CrossRef] [PubMed]
Doornewaard, R.; Sakani, S.; Matthys, C.; Glibert, M.; Bronkhorst, E.; Vandeweghe, S.; Vervaeke, S.; De Bruyn, H. Four-Implant-Supported Overdenture Treatment in the Maxilla. Part I: A Randomized Controlled Split Mouth Trial Assessing the Effect of Microthreads and Abutment Connection Type on 4 Years Peri-Implant Health. Clin. Implant Dent. Relat. Res. 2021, 23, 671–679. [Google Scholar] [CrossRef] [PubMed]
Pieri, F.; Aldini, N.N.; Marchetti, C.; Corinaldesi, G. Influence of Implant-Abutment Interface Design on Bone and Soft Tissue Levels around Immediately Placed and Restored Single-Tooth Implants: A Randomized Controlled Clinical Trial. Int. J. Oral Maxillofac. Implants 2011, 26, 169–178. [Google Scholar] [PubMed]
Ogino, Y.; Matsushita, Y.; Sasaki, M.; Ayukawa, Y.; Koyano, K. A 3-Year Prospective Study on Radiographic Marginal Bone Evaluation Around Platform-Shifting Implants with Internal Conical Connections. Int. J. Oral Maxillofac. Implants 2021, 36, 574–580. [Google Scholar] [CrossRef]
Corvino, E.; Pesce, P.; Camodeca, F.; Moses, O.; Iannello, G.; Canullo, L. Clinical and Radiological Outcomes of Implants with Two Different Connection Configurations: A Randomised Controlled Trial. Int. J. Oral Implantol. 2020, 13, 355–368. [Google Scholar]
Farronato, D.; Manfredini, M.; Stocchero, M.; Caccia, M.; Azzi, L.; Farronato, M. Influence of Bone Quality, Drilling Protocol, Implant Diameter/Length on Primary Stability: An In Vitro Comparative Study on Insertion Torque and Resonance Frequency Analysis. J. Oral Implantol. 2020, 46, 182–189. [Google Scholar] [CrossRef]
Moroi, A.; Saito, Y.; Takayama, A.; Ueki, K. Comparison of Nonself-Tapping Tapered Implant and Self-Tapping Hybrid Implant in Terms of Implant Stability at Initial and Second Fixation: A Prospective Randomized Clinical Trial. Clin. Implant Dent. Relat. Res. 2020, 22, 679–688. [Google Scholar] [CrossRef]
Bernard, L.; Vercruyssen, M.; Vanderveken, J.; Coucke, W.; Quirynen, M.; Naert, I. Randomized Controlled Trial Comparing Immediate Loading with Conventional Loading Using Cone-Anchored Implant-Supported Screw-Retained Removable Prostheses: A 2-Year Follow-up Clinical Trial. J. Prosthet. Dent. 2019, 121, 258–264. [Google Scholar] [CrossRef]
Guarnieri, R.; Grande, M.; Ippoliti, S.; Iorio-Siciliano, V.; Riccitiello, F.; Farronato, D. Influence of a Laser-Lok Surface on Immediate Functional Loading of Implants in Single-Tooth Replacement: Three-Year Results of a Prospective Randomized Clinical Study on Soft Tissue Response and Esthetics. Int. J. Periodontics Restor. Dent. 2015, 35, 865–875. [Google Scholar] [CrossRef]
McGuire, M.K.; Scheyer, T.; Ho, D.K.; Stanford, C.M.; Feine, J.S.; Cooper, L.F. Esthetic Outcomes in Relation to Implant-Abutment Interface Design Following a Standardized Treatment Protocol in a Multicenter Randomized Controlled Trial--a Cohort of 12 Cases at 1-Year Follow-Up. Int. J. Periodontics Restor. Dent. 2015, 35, 149–159. [Google Scholar] [CrossRef] [PubMed][Green Version]
Koutouzis, T.; Mesia, R.; Calderon, N.; Wong, F.; Wallet, S. The Effect of Dynamic Loading on Bacterial Colonization of the Dental Implant Fixture–Abutment Interface: An In Vitro Study. J. Oral Implantol. 2014, 40, 432–437. [Google Scholar] [CrossRef] [PubMed]
Koutouzis, T.; Neiva, R.; Nonhoff, J.; Lundgren, T. Placement of Implants with Platform-Switched Morse Taper Connections with the Implant-Abutment Interface at Different Levels in Relation to the Alveolar Crest: A Short-Term (1-Year) Randomized Prospective Controlled Clinical Trial. Int. J. Oral Maxillofac. Implants 2013, 28, 1553–1563. [Google Scholar] [CrossRef] [PubMed]
Afrashtehfar, K.I.; Weber, A.; Abou-Ayash, S. Titanium-Base Abutments May Have Similar Long-Term Peri-Implant Effects as Non-Bonded One-Piece Abutments. Evid. Based Dent. 2022, 23, 134–135. [Google Scholar] [CrossRef]
Meloni, S.M.; Melis, L.; Xhanari, E.; Tallarico, M.; Spano, G.; Pisano, M.; Baldoni, E.; Cervino, G.; Tullio, A.; Lumbau, A.I. Three-Year Retrospective Comparative Study between Implants with Same Body-Design but Different Crest Module Configurations. Dent. J. 2020, 8, 135. [Google Scholar] [CrossRef]
Park, H.; Moon, I.-S.; Chung, C.; Shin, S.-J.; Huh, J.-K.; Yun, J.-H.; Lee, D.-W. Comparison of Peri-Implant Marginal Bone Level Changes between Tapered and Straight Implant Designs: 5-Year Follow-up Results. J. Periodontal Implant Sci. 2021, 51, 422–432. [Google Scholar] [CrossRef]
Kruse, A.B.; Wild, V.; Ratka-Krüger, P.; Vach, K.; Frisch, E. Peri-Implant Bone-Level Changes in the Second Decade of Loading with Regard to the Implant-Abutment Connection: A Retrospective Study on Implants under Systematic Aftercare. Int. J. Implant Dent. 2021, 7, 104. [Google Scholar] [CrossRef]
Canullo, L.; Menini, M.; Bagnasco, F.; Di Tullio, N.; Pesce, P. Tissue-Level versus Bone-Level Single Implants in the Anterior Area Rehabilitated with Feather-Edge Crowns on Conical Implant Abutments: An up to 5-Year Retrospective Study. J. Prosthet. Dent. 2022, 128, 936–941. [Google Scholar] [CrossRef]
Baldi, D.; Colombo, J.; Verardi, S.; Rebaudi, A.; Rebaudi, F.; Makary, C. Clinical Osseointegration of Bone Level Implants with Conical Shape and Textured Surface with Low Primary Stability. Minerva Stomatol. 2020, 69, 8–13. [Google Scholar] [CrossRef]
Thomé, G.; Cartelli, C.A.; Vianna, C.P.; Trojan, L.C. Retrospective Clinical Study of 453 Novel Tapered Implants Placed in All Bone Types: Survival Rate Analysis Up to 2 Years of Follow-Up. Int. J. Oral Maxillofac. Implants 2020, 35, 757–761. [Google Scholar] [CrossRef]
Koutouzis, T.; Podaru, A.; Neiva, R. Facial Peri-Implant Soft Tissue Topography of Posterior Single Implant-Supported Restorations and Relationship to Adjacent Teeth: A Retrospective Analysis. Int. J. Oral Maxillofac. Implants 2015, 30, 681–687. [Google Scholar] [CrossRef] [PubMed][Green Version]
Romanos, G.; Grizas, E.; Laukart, E.; Nentwig, G.-H. Effects of Early Moderate Loading on Implant Stability: A Retrospective Investigation of 634 Implants with Platform Switching and Morse-Tapered Connections. Clin. Implant Dent. Relat. Res. 2016, 18, 301–309. [Google Scholar] [CrossRef] [PubMed]
Simonpieri, A.; Gasparro, R.; Pantaleo, G.; Mignogna, J.; Riccitiello, F.; Sammartino, G. Four-Year Post-Loading Results of Full-Arch Rehabilitation with Immediate Placement and Immediate Loading Implants: A Retrospective Controlled Study. Quintessence Int. 2017, 48, 315–324. [Google Scholar] [CrossRef] [PubMed]
Guarnieri, R.; Placella, R.; Testarelli, L.; Iorio-Siciliano, V.; Grande, M. Clinical, Radiographic, and Esthetic Evaluation of Immediately Loaded Laser Microtextured Implants Placed into Fresh Extraction Sockets in the Anterior Maxilla: A 2-Year Retrospective Multicentric Study. Implant Dent. 2014, 23, 144–154. [Google Scholar] [CrossRef]
Machtei, E.E.; Oved-Peleg, E.; Peled, M. Comparison of Clinical, Radiographic and Immunological Parameters of Teeth and Different Dental Implant Platforms. Clin. Oral Implants Res. 2006, 17, 658–665. [Google Scholar] [CrossRef]
Romanos, G.E.; May, S.; May, D. Treatment Concept of the Edentulous Mandible with Prefabricated Telescopic Abutments and Immediate Functional Loading. Int. J. Oral Maxillofac. Implants 2011, 26, 593–597. [Google Scholar]
Lin, M.I.; Shen, Y.W.; Huang, H.L.; Hsu, J.T.; Fuh, L.J. A Retrospective Study of Implant-Abutment Connections on Crestal Bone Level. J. Dent. Res. 2013, 92, 202S–207S. [Google Scholar] [CrossRef]
Lopez, M.A.; Andreasi Bassi, M.; Confalone, L.; Gaudio, R.M.; Lombardo, L.; Lauritano, D. Clinical Outcome of 215 Transmucosal Implants with a Conical Connection: A Retrospective Study after 5-Year Follow-Up. J. Biol. Regul. Homeost. Agents 2016, 30, 55–60. [Google Scholar]
Lops, D.; Stocchero, M.; Motta Jones, J.; Freni, A.; Palazzolo, A.; Romeo, E. Five Degree Internal Conical Connection and Marginal Bone Stability around Subcrestal Implants: A Retrospective Analysis. Materials 2020, 13, 3123. [Google Scholar] [CrossRef]
Canullo, L.; Hjerppe, J.; Menini, M.; Bagnasco, F.; Petazzi, G.M.; Pesce, P. Zirconia Crowns and FDPs with Feather-Edge Margins on Conical Implant Abutments-Up-To-5-Year Clinical Retrospective Study. Int. J. Prosthodont. 2022, 35, 380–386. [Google Scholar] [CrossRef]
Al-Fakeh, H.; Sharhan, H.M.; Ziyad, T.A.; Abdulghani, E.A.; Al-Moraissi, E.; Al-Sosowa, A.A.; Liu, B.; Zhang, K. Three-Dimensional Radiographic Assessment of Bone Changes around Posterior Dental Implants at Native Bone Site in Gansu Province, Northwest of China: A Retrospective Cohort Study. J. Stomatol. Oral Maxillofac. Surg. 2022, 123, e186–e191. [Google Scholar] [CrossRef] [PubMed]
Ding, Y.; Zhou, H.; Zhang, W.; Chen, J.; Zheng, Y.; Wang, L.; Yang, F. Evaluation of a Platform-Switched Morse Taper Connection for All-on-Four or Six Treatment in Edentulous or Terminal Dentition Treatment: A Retrospective Study with 1-8 Years of Follow-Up. Clin. Implant Dent. Relat. Res. 2023, 25, 815–828. [Google Scholar] [CrossRef] [PubMed]
Mangano, C.; Iaculli, F.; Piattelli, A.; Mangano, F. Fixed Restorations Supported by Morse-Taper Connection Implants: A Retrospective Clinical Study with 10-20 Years of Follow-Up. Clin. Oral Implants Res. 2015, 26, 1229–1236. [Google Scholar] [CrossRef] [PubMed]
Gehrke, S.A.; Scarano, A.; Cortellari, G.C.; Fernandes, G.V.O.; Mesquita, A.M.M.; Bianchini, M.A. Marginal Bone Level and Biomechanical Behavior of Titanium-Indexed Abutment Base of Conical Connection Used for Single Ceramic Crowns on Morse-Taper Implant: A Clinical Retrospective Study. J. Funct. Biomater. 2023, 14, 128. [Google Scholar] [CrossRef]
Tallarico, M.; Lumbau, A.M.I.; Meloni, S.M.; Ieria, I.; Park, C.-J.; Zadrożny, L.; Xhanari, E.; Pisano, M. Five-Year Prospective Study on Implant Failure and Marginal Bone Remodeling Expected Using Bone Level Implants with Sandblasted/Acid-Etched Surface and Conical Connection. Eur. J. Dent. 2022, 16, 787–795. [Google Scholar] [CrossRef]
Apaza-Bedoya, K.; Galarraga-Vinueza, M.E.; Correa, B.B.; Schwarz, F.; Bianchini, M.A.; Magalhães Benfatti, C.A. Prevalence, Risk Indicators, and Clinical Characteristics of Peri-Implant Mucositis and Peri-Implantitis for an Internal Conical Connection Implant System: A Multicenter Cross-Sectional Study. J. Periodontol. 2024, 95, 582–593. [Google Scholar] [CrossRef]
Linkevicius, T.; Puisys, A.; Svediene, O.; Linkevicius, R.; Linkeviciene, L. Radiological Comparison of Laser-Microtextured and Platform-Switched Implants in Thin Mucosal Biotype. Clin. Oral Implants Res. 2015, 26, 599–605. [Google Scholar] [CrossRef]
Weigl, P.; Trimpou, G.; Lorenz, J.; Nentwig, G.-H.; Lauer, H.-C. Prefabricated Taper Crowns for the Retention of Implant Superstructures: Three-Year Results of a Prospective Clinical Trial. J. Prosthet. Dent. 2019, 121, 618–622. [Google Scholar] [CrossRef]
Sun, Y.; Yang, J.; Chen, K.; Li, Z.; Chen, Z.; Huang, B. Clinical and Radiographic Results of Crestal vs. Subcrestal Placement of Implants in Posterior Areas: A Split-Mouth Randomized Controlled Clinical Trial. Clin. Implant Dent. Relat. Res. 2023, 25, 948–959. [Google Scholar] [CrossRef]
Saglanmak, A.; Gultekin, A.; Cinar, C.; Szmukler-Moncler, S.; Karabuda, C. Effect of Soft Tissue Thickness on Crestal Bone Loss of Early Loaded Implants with Platform Switching: 1- and 5-Year Data. Quintessence Int. 2021, 52, 426–433. [Google Scholar] [CrossRef]
Penitente, P.A.; do Vale Souza, J.P.; Dos Santos, D.M.; Brunetto, J.L.; de Moraes Melo Neto, C.L.; Bueno Carlini Bittencourt, A.B.; de Sousa Ervolino, I.C.; Goiato, M.C. Survival of Osseointegrated Implants: A 10-Year Retrospective Study. Clin. Ter. 2023, 174, 180–184. [Google Scholar] [CrossRef] [PubMed]
Frisch, E.; Ziebolz, D.; Ratka-Krüger, P.; Rinke, S. Double Crown-Retained Maxillary Overdentures: 5-Year Follow-Up. Clin. Implant Dent. Relat. Res. 2015, 17, 22–31. [Google Scholar] [CrossRef] [PubMed]
Ho, D.S.W.; Yeung, S.C.H.; Zee, K.Y.; Curtis, B.; Hell, P.; Tumuluri, V. Clinical and Radiographic Evaluation of NobelActive(TM) Dental Implants. Clin. Oral Implants Res. 2013, 24, 297–304. [Google Scholar] [CrossRef] [PubMed]
Mangano, F.; Mangano, C.; Ricci, M.; Sammons, R.L.; Shibli, J.A.; Piattelli, A. Single-Tooth Morse Taper Connection Implants Placed in Fresh Extraction Sockets of the Anterior Maxilla: An Aesthetic Evaluation. Clin. Oral Implants Res. 2012, 23, 1302–1307. [Google Scholar] [CrossRef]
Mangano, C.; Mangano, F.; Shibli, J.A.; Ricci, M.; Sammons, R.L.; Figliuzzi, M. Morse Taper Connection Implants Supporting “Planned” Maxillary and Mandibular Bar-Retained Overdentures: A 5-Year Prospective Multicenter Study. Clin. Oral Implants Res. 2011, 22, 1117–1124. [Google Scholar] [CrossRef]
Mangano, C.; Mangano, F.; Shibli, J.A.; Tettamanti, L.; Figliuzzi, M.; d’Avila, S.; Sammons, R.L.; Piattelli, A. Prospective Evaluation of 2,549 Morse Taper Connection Implants: 1- to 6-Year Data. J. Periodontol. 2011, 82, 52–61. [Google Scholar] [CrossRef]
Moberg, L.E.; Köndell, P.A.; Kullman, L.; Heimdahl, A.; Gynther, G.W. Evaluation of Single-Tooth Restorations on ITI Dental Implants. A Prospective Study of 29 Patients. Clin. Oral Implants Res. 1999, 10, 45–53. [Google Scholar] [CrossRef]
Levine, R.A.; Clem, D.S., 3rd; Wilson, T.G.J.; Higginbottom, F.; Saunders, S.L. A Multicenter Retrospective Analysis of the ITI Implant System Used for Single-Tooth Replacements: Preliminary Results at 6 or More Months of Loading. Int. J. Oral Maxillofac. Implants 1997, 12, 237–242. [Google Scholar]
Chapman, R.J.; Grippo, W. The Locking Taper Attachment for Implant Abutments: Use and Reliability. Implant Dent. 1996, 5, 257–261. [Google Scholar] [CrossRef]
Morris, H.F.; Winkler, S.; Ochi, S.; Kanaan, A. A New Implant Designed to Maximize Contact with Trabecular Bone: Survival to 18 Months. J. Oral Implantol. 2001, 27, 164–173. [Google Scholar] [CrossRef]
Mangano, C.; Bartolucci, E.G. Single Tooth Replacement by Morse Taper Connection Implants: A Retrospective Study of 80 Implants. Int. J. Oral Maxillofac. Implants 2001, 16, 675–680. [Google Scholar] [PubMed]
Gatti, C.; Chiapasco, M. Immediate Loading of Brånemark Implants: A 24-Month Follow-up of a Comparative Prospective Pilot Study between Mandibular Overdentures Supported by Conical Transmucosal and Standard MK II Implants. Clin. Implant Dent. Relat. Res. 2002, 4, 190–199. [Google Scholar] [CrossRef] [PubMed]
Kronström, M.; Widbom, T.; Löfquist, L.E.; Henningson, C.; Widbom, C.; Lundberg, T. Early Functional Loading of Conical Brånemark Implants in the Edentulous Mandible: A 12-Month Follow-up Clinical Report. J. Prosthet. Dent. 2003, 89, 335–340. [Google Scholar] [CrossRef] [PubMed]
Chou, C.-T.; Morris, H.F.; Ochi, S.; Walker, L.; DesRosiers, D. AICRG, Part II: Crestal Bone Loss Associated with the Ankylos Implant: Loading to 36 Months. J. Oral Implantol. 2004, 30, 134–143. [Google Scholar] [CrossRef]
Toia, M.; Parpaiola, A.; Stevanello, N.; Tattan, M.; Saleh, M.H.A.; Ravidà, A. Clinical Outcomes of Implant- versus Abutment-Level Connection in Screw-Retained Fixed Dental Prostheses: A 5-Year Randomized Controlled Trial. Clin. Oral Implants Res. 2024, 35, 230–241. [Google Scholar] [CrossRef]
Galindo-Moreno, P.; Catena, A.; Lopez-Chaichio, L.; Borges, T.; O’Valle, F.; Torrecillas-Martínez, L.; Padial-Molina, M. The Influence of History of Severe Periodontitis on Estimated Long-Term Marginal Bone Loss around Implants Restored with Fixed Segmented Full-Arch Rehabilitation. J. Clin. Med. 2023, 12, 6665. [Google Scholar] [CrossRef]
Gehrke, S.A.; Cortellari, G.C.; De Oliveira Fernandes, G.V.; Scarano, A.; Martins, R.G.; Cançado, R.M.; Mesquita, A.M.M. Randomized Clinical Trial Comparing Insertion Torque and Implant Stability of Two Different Implant Macrogeometries in the Initial Periods of Osseointegration. Medicina 2023, 59, 168. [Google Scholar] [CrossRef]
Lops, D.; Romeo, E.; Stocchero, M.; Palazzolo, A.; Manfredi, B.; Sbricoli, L. Marginal Bone Maintenance and Different Prosthetic Emergence Angles: A 3-Year Retrospective Study. J. Clin. Med. 2022, 11, 2014. [Google Scholar] [CrossRef]
Mangalvedhekar, M.; Manas, A.; Jyothirmayee, K.; Richashreev; Tenglikar, P.; Das, A.C. Assessment of Clinical and Radiological Outcome of Implant with Two Different Connections Con Iguration: A Controlled Trial. J. Pharm. Bioallied Sci. 2022, 14, S974–S976. [Google Scholar] [CrossRef]
Friberg, B.; Ahmadzai, M. A Prospective Study on Single Tooth Reconstructions Using Parallel Walled Implants with Internal Connection (NobelParallel CC) and Abutments with Angulated Screw Channels (ASC). Clin. Implant Dent. Relat. Res. 2019, 21, 226–231. [Google Scholar] [CrossRef]
Mundt, T.; Mack, F.; Schwahn, C.; Biffar, R. Private Practice Results of Screw-Type Tapered Implants: Survival and Evaluation of Risk Factors. Int. J. Oral Maxillofac. Implants 2006, 21, 607–614. [Google Scholar] [PubMed]
Mangano, C.; Mangano, F.; Piatelli, A.; Lezzi, G.; Mangano, A.; La Colla, L.; Mangano, A. Single-Tooth Morse Taper Connection Implants after 1 Year of Functional Loading: A Multicentre Study on 302 Patients. Eur. J. Oral Implantol. 2008, 1, 305–315. [Google Scholar] [PubMed]
Mangano, C.; Mangano, F.; Piattelli, A.; Iezzi, G.; Mangano, A.; La Colla, L. Prospective Clinical Evaluation of 1920 Morse Taper Connection Implants: Results after 4 Years of Functional Loading. Clin. Oral Implants Res. 2009, 20, 254–261. [Google Scholar] [CrossRef] [PubMed]
Mangano, C.; Mangano, F.; Piattelli, A.; Iezzi, G.; Mangano, A.; La Colla, L. Prospective Clinical Evaluation of 307 Single-Tooth Morse Taper-Connection Implants: A Multicenter Study. Int. J. Oral Maxillofac. Implants 2010, 25, 394–400. [Google Scholar]
Gultekin, B.A.; Gultekin, P.; Leblebicioglu, B.; Basegmez, C.; Yalcin, S. Clinical Evaluation of Marginal Bone Loss and Stability in Two Types of Submerged Dental Implants. Int. J. Oral Maxillofac. Implants 2013, 28, 815–823. [Google Scholar] [CrossRef]
Pozzi, A.; Agliardi, E.; Tallarico, M.; Barlattani, A. Clinical and Radiological Outcomes of Two Implants with Different Prosthetic Interfaces and Neck Configurations: Randomized, Controlled, Split-Mouth Clinical Trial. Clin. Implant Dent. Relat. Res. 2014, 16, 96–106. [Google Scholar] [CrossRef]
Pozzi, A.; Tallarico, M.; Moy, P.K. Immediate Loading with a Novel Implant Featured by Variable-Threaded Geometry, Internal Conical Connection and Platform Shifting: Three-Year Results from a Prospective Cohort Study. Eur. J. Oral Implantol. 2015, 8, 51–63. [Google Scholar]
Gao, W.M.; Geng, W.; Luo, C.C. Prosthetic Complications of Fixed Dental Prostheses Supported by Locking-Taper Implants: A Retrospective Study with a Mean Follow-up of 5 Years. BMC Oral Health 2021, 21, 476. [Google Scholar] [CrossRef]
Cooper, L.F.; Reside, G.; DeKok, I.; Stanford, C.; Barwacz, C.; Feine, J.; Nader, S.A.; Scheyer, T.; McGuire, M. A 5-Year Esthetic RCT Assessment of Anterior Maxillary Single-Tooth Implants with Different Abutment Interfaces. Int. J. Oral Maxillofac. Implants 2021, 36, 165–176. [Google Scholar] [CrossRef]
Dev, S.V.; Perti, S.; Sahoo, K.K.; Mohanty, A.; Pati, S.K.; Sri, A.N. A Comprehensive Assessment of Bone Losses in the Postoperative Phase of Single Implant Placed in Mandibular First Molar Regions: A Cone-Beam Computed Tomography-Based Clinical Study. J. Pharm. Bioallied Sci. 2021, 13, S1530–S1534. [Google Scholar] [CrossRef]
Paganelli, O.E.B.; Santos, P.L.; Spin-Neto, R.; Pereira-Filho, V.A.; Margonar, R. Stability of Mandibular Implants with Morse Taper and External Hexagon Connections Placed under Immediate Loading: A Longitudinal Clinical Study. Gen. Dent. 2022, 70, 50–54. [Google Scholar] [PubMed]
Ceruso, F.M.; Ieria, I.; Tallarico, M.; Meloni, S.M.; Lumbau, A.I.; Mastroianni, A.; Zotti, A.; Gargari, M. Comparison between Early Loaded Single Implants with Internal Conical Connection or Implants with Transmucosal Neck Design: A Non-Randomized Controlled Trial with 1-Year Clinical, Aesthetics, and Radiographic Evaluation. Materials 2022, 15, 511. [Google Scholar] [CrossRef] [PubMed]
Raj, H.K.; Mohan, T.K.; Kattimani, V.; Sreerama, R.; Ramya, Y.; Inampudi, C.K. Evaluation of Immediately Loaded Parallel Conical Connection Implants with Platform Switch in the Maxillary Esthetic Zone: A Prospective Clinical Study. J. Contemp. Dent. Pract. 2022, 23, 405–414. [Google Scholar] [CrossRef] [PubMed]
Radaelli, M.T.B.; Federizzi, L.; Nascimento, G.G.; Leite, F.R.M.; Boscato, N. Early-Predictors of Marginal Bone Loss around Morse Taper Connection Implants Loaded with Single Crowns: A Prospective Longitudinal Study. J. Periodontal Res. 2020, 55, 174–181. [Google Scholar] [CrossRef] [PubMed]
Mihali, S.G.; Wang, H.-L.; Karancsi, O.; Bratu, E.A. Internal Hexagon vs. Conical Implant-Abutment Connections: Evaluation of 3-Year Postloading Outcomes. J. Oral Implantol. 2021, 47, 485–490. [Google Scholar] [CrossRef]
Stacchi, C.; Lamazza, L.; Rapani, A.; Troiano, G.; Messina, M.; Antonelli, A.; Giudice, A.; Lombardi, T. Marginal Bone Changes around Platform-Switched Conical Connection Implants Placed 1 or 2 Mm Subcrestally: A Multicenter Crossover Randomized Controlled Trial. Clin. Implant Dent. Relat. Res. 2023, 25, 398–408. [Google Scholar] [CrossRef]
Linkevicius, T.; Linkevicius, R.; Gineviciute, E.; Alkimavicius, J.; Mazeikiene, A.; Linkeviciene, L. The Influence of New Immediate Tissue Level Abutment on Crestal Bone Stability of Subcrestally Placed Implants: A 1-Year Randomized Controlled Clinical Trial. Clin. Implant Dent. Relat. Res. 2021, 23, 259–269. [Google Scholar] [CrossRef]
Hartmann, R.; Bandeira, A.C.F.d.M.; de Araújo, S.C.; Brägger, U.; Schimmel, M.; Leles, C.R. A Parallel 3-Group Randomised Clinical Trial Comparing Different Implant Treatment Options for the Edentulous Mandible: 1-Year Effects on Dental Patient-Reported Outcomes and Chewing Function. J. Oral Rehabil. 2020, 47, 1264–1277. [Google Scholar] [CrossRef]
Pessoa, R.S.; Sousa, R.M.; Pereira, L.M.; Neves, F.D.; Bezerra, F.J.B.; Jaecques, S.V.N.; Sloten, J.V.; Quirynen, M.; Teughels, W.; Spin-Neto, R. Bone Remodeling Around Implants with External Hexagon and Morse-Taper Connections: A Randomized, Controlled, Split-Mouth, Clinical Trial. Clin. Implant Dent. Relat. Res. 2017, 19, 97–110. [Google Scholar] [CrossRef]
Galindo-Moreno, P.; Concha-Jeronimo, A.; Lopez-Chaichio, L.; Rodriguez-Alvarez, R.; Sanchez-Fernandez, E.; Padial-Molina, M. Marginal Bone Loss around Implants with Internal Hexagonal and Internal Conical Connections: A 12-Month Randomized Pilot Study. J. Clin. Med. 2021, 10, 5427. [Google Scholar] [CrossRef]
Studenikin, R. Prosthodontics Using Removable Platform Switching Technologies (Multiunit, On1) as Exemplified by Conical Connection Implant Systems for Early and Immediate Loading. Int. J. Dent. 2021, 2021, 6633804. [Google Scholar] [CrossRef] [PubMed]
Abi Rached, S.; Chakar, C.; Samarani, R.; Menassa, G.; Sembronio, S.; Pucci, R.; Calabrese, L.; Cantore, S.; Malcangi, A.; Spirito, F.; et al. Radiographic Marginal Bone Level Evaluation around Two Different Tissue-Level Implant Systems: A One-Year Prospective Study. Minerva Dent. Oral Sci. 2023, 72, 298–311. [Google Scholar] [CrossRef] [PubMed]
Bae, M.-S.; Sohn, D.-S.; Ahn, M.-R.; Lee, H.-W.; Jung, H.-S.; Shin, I.-H. Retrospective Multicenter Evaluation of Tapered Implant with a Sandblasted and Acid-Etched Surface at 1 to 4 Years of Function. Implant Dent. 2011, 20, 280–284. [Google Scholar] [CrossRef]
Palmer, R.M.; Smith, B.J.; Palmer, P.J.; Floyd, P.D. A Prospective Study of Astra Single Tooth Implants. Clin. Oral Implants Res. 1997, 8, 173–179. [Google Scholar] [CrossRef] [PubMed]
Pozzi, A.; Tabanella, G.; Guida, A.; Hugo, O.; Authelain, C.; Scheyer, E.T.; McGuire, M.K.; Lipton, D. A Novel Parallel-Walled Dental Implant with a Self-Tapping Apex, Conical Connection, and Platform Shifting: Short-Term Results from a Retrospective Multicenter Clinical Study. Int. J. Periodontics Restor. Dent. 2021, 41, 521–529. [Google Scholar] [CrossRef] [PubMed]
Eskan, M.A.; Uzel, G.; Yilmaz, S. A Fixed Reconstruction of Fully Edentulous Patients with Immediate Function Using an Apically Tapered Implant Design: A Retrospective Clinical Study. Int. J. Implant Dent. 2020, 6, 77. [Google Scholar] [CrossRef]
Palaska, I.; Tsaousoglou, P.; Vouros, I.; Konstantinidis, A.; Menexes, G. Influence of Placement Depth and Abutment Connection Pattern on Bone Remodeling around 1-Stage Implants: A Prospective Randomized Controlled Clinical Trial. Clin. Oral Implants Res. 2016, 27, e47–e56. [Google Scholar] [CrossRef]
Galindo-Moreno, P.; Ravidà, A.; Catena, A.; O’Valle, F.; Padial-Molina, M.; Wang, H.-L. Limited Marginal Bone Loss in Implant-Supported Fixed Full-Arch Rehabilitations after 5 Years of Follow-Up. Clin. Oral Implants Res. 2022, 33, 1224–1232. [Google Scholar] [CrossRef]
Pariente, L.; Dada, K.; Daas, M.; Linder, S.; Dard, M. Evaluation of the Treatment of Partially Edentulous Patients With Bone Level Tapered Implants: 24-Month Clinical and Radiographic Follow-Up. J. Oral Implantol. 2020, 46, 407–413. [Google Scholar] [CrossRef]
Scarano, A.; Khater, A.G.A.; Gehrke, S.A.; Serra, P.; Francesco, I.; Di Carmine, M.; Tari, S.R.; Leo, L.; Lorusso, F. Current Status of Peri-Implant Diseases: A Clinical Review for Evidence-Based Decision Making. J. Funct. Biomater. 2023, 14, 210. [Google Scholar] [CrossRef]
Scarano, A.; Valbonetti, L.; Degidi, M.; Pecci, R.; Piattelli, A.; de Oliveira, P.S.; Perrotti, V. Implant-Abutment Contact Surfaces and Microgap Measurements of Different Implant Connections Under 3-Dimensional X-Ray Microtomography. Implant Dent. 2016, 25, 656–662. [Google Scholar] [CrossRef] [PubMed]
Prithviraj, D.; Muley, N. Evolution of External and Internal Implant to Abutment Connection. Int. J. Oral Implantol. Clin. Res. 2012, 3, 122–129. [Google Scholar] [CrossRef]
Baj, A.; Bolzoni, A.; Russillo, A.; Lauritano, D.; Palmieri, A.; Cura, F.; Silvestre, F.J.; Giannì, A.B. Cone-Morse Implant Connection System Significantly Reduces Bacterial Leakage between Implant and Abutment: An in Vitro Study. J. Biol. Regul. Homeost. Agents 2017, 31, 203–208. [Google Scholar] [PubMed]
Bittencourt, A.B.B.C.; Neto, C.L.d.M.M.; Penitente, P.A.; Pellizzer, E.P.; Dos Santos, D.M.; Goiato, M.C. Comparison of the Morse Cone Connection with the Internal Hexagon and External Hexagon Connections Based on Microleakage—Review. Prague Med. Rep. 2021, 122, 181–190. [Google Scholar] [CrossRef]
Gil, F.J.; Herrero-Climent, M.; Lázaro, P.; Rios, J.V. Implant–Abutment Connections: Influence of the Design on the Microgap and Their Fatigue and Fracture Behavior of Dental Implants. J. Mater. Sci. Mater. Med. 2014, 25, 1825–1830. [Google Scholar] [CrossRef]
Scarano, A.; Bartolomeo, A.; Piattelli, M.; Iezzi, G.; Alessandro, Q.; Pietro, T.; Piattelli, A. Retrospective Evaluation of the Microgap between Implants and Abutments in 272 Titanium Implants Retrieved from Man: A 16 Years Experience (1989–2004). J. Oral Implantol. 2005, 31, 269–275. [Google Scholar] [CrossRef]
Lorusso, F.; Greco Lucchina, A.; Romano, F.; Falisi, G.; Di Carmine, M.S.; Bugea, C.; Scarano, A. Microleakage and Mechanical Behavior of Conical vs. Internal Hexagon Implant-Abutment Connection under a Cyclic Load Fatigue Test. Eur. Rev. Med. Pharmacol. Sci. 2023, 27, 122–127. [Google Scholar] [CrossRef]
Babaji, P.; Parihar, A.S.; Parihar, A.S.; Jagadeesh, K.N.; Alduwayhi, S.; Annapoorneshwari, S.; Khalid, F.M. Evaluation of Microleakage and Microgap of Two Different Internal Implant-Abutment Connections: An In Vitro Study. J. Contemp. Dent. Pract. 2020, 21, 683–685. [Google Scholar] [CrossRef]
Tsuruta, K.; Ayukawa, Y.; Matsuzaki, T.; Kihara, M.; Koyano, K. The Influence of Implant–Abutment Connection on the Screw Loosening and Microleakage. Int. J. Implant Dent. 2018, 4, 11. [Google Scholar] [CrossRef]

Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

© 2025 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

	Search Strategies
Keywords search:	(taper OR cone OR conical OR Cone morse) AND dental implant
Timespan	No limitations (1995–2023)
Electronic Databases	Pubmed/Medline, EMBASE, Google Scholar

Peri-Implant Bone Stability Around Tapered Implant Prosthetic Connection: A Systematic Review and Meta-Analysis Comparing Different Cone Morse and Conometric Implants Angle Contact and Coupling Interface Designs

Abstract

1. Introduction

2. Materials and Methods

2.1. Preliminary Screening Strategy

2.2. Inclusion Criteria

2.3. Study Data Extraction

2.4. Risk of Bias Assessment

2.5. Heterogeneity Measurement and Meta-Analysis

3. Results

3.1. Screening Output

3.2. General Characteristics of the Studies Included

3.3. Complications

3.4. Risk of Bias Assessment (RoB)

3.5. Meta-Analysis

3.6. Meta-Regression MBL

4. Discussion

5. Conclusions

Author Contributions

Funding

Institutional Review Board Statement

Informed Consent Statement

Data Availability Statement

Conflicts of Interest

References

Article Metrics

Citations

Article Access Statistics