The Use of Tissue Grafts Associated with Immediate Implant Placement to Achieve Better Peri-Implant Stability and Efficacy: A Systematic Review and Meta-Analysis

Background: The goal of this systematic study and meta-analysis was to evaluate the efficacy of hard and/or soft tissue grafts associated with type-1 implants on healing and treatment outcomes. The primary outcomes studied were implant survival rate, pocket depth, marginal peri-implant recession, bone loss, bone thickness (volumetric change), interproximal bone level, mesial and distal papilla migration, and radiographic evaluation; and the secondary parameters were Pink Esthetic Score (PES), vertical distance from implant shoulder and bone, Visual Analogue Score (VAS), Implant Stability Quotient (ISQ), and biological complications (fistulas, pain, mucositis, and peri-implantitis). Methods: The PICO strategy was used to formulate the hypothesis under study: “For patients who underwent extraction and immediate implant placement, what is the efficacy of using any type of graft (bone or soft tissue) compared to non-grafting regarding the peri-implant parameters?” The electronic search process was performed on the MedLine/PubMed and Cochrane databases. It included randomized controlled trials (RCTs) from the last 11 years (from 2012 to November 2023), which were identified and analyzed. Results: Nine RCTs (κ = 0.98) were selected (403 patients and 425 implants); they were divided into three groups: bone graft (75 patients and 75 implants inserted), bone graft and membrane (213 patients and 235 implants inserted), and without bone graft (115 patients and 115 implants inserted). Three studies calculated the mid-facial mucosa level and two reported better results when a connective tissue graft was combined with the xenograft, whereas another study found better results in the combination of a dual-zone technique with a xenograft. Three studies evaluated the total Pink Esthetic Score (PES) at 12 months, where the authors found no significant difference in using a xenogeneic graft with or without a membrane. In the same period, the facial bone thickness was assessed in two articles; the authors reported better results in graft-treated and flapless groups. The risk-of-bias assessment found four studies with low risk, four with moderate risk, and one with a high risk of bias. The meta-analysis showed a medium level of heterogeneity for the mid-facial mucosa level analysis (I2 = 46%) and an overall effect size of 0.79 (95% CI [0.18; 1.40]), a statistically significant results (p = 0.01), with a tendency to favor the experimental group. Also, there was a medium level of heterogeneity among studies regarding total PES (I2 = 45%), with no significant differences between studies (p = 0.91). Homogeneous results (I2 = 0%) were found among studies analyzing facial bone thickness, favoring the experimental group; the forest plot showed an effect of 0.37 (95% CI [0.25; 0.50]), which was statistically significant (p < 0.00001) for this parameter. Conclusions: Then, it was possible to conclude that using bone and soft tissue grafting techniques associated with immediate implant placement (IIP), even though they are not fundamental, was a valuable resource to prevent significant tissue reduction, reaching greater bone stability and higher levels in the Pink Esthetic Score (PES) and Visual Analogue Score (VAS).


Introduction
Implant rehabilitation techniques involve using biomaterials [1,2] and titanium/zirconia to replace one or more teeth [3].The classification of implant surgery techniques was developed based on alveolar healing times and included the following: type-1 protocol, immediate implantation (IIP), extraction and insertion in the same surgical protocol; type-2 protocol, early implant, insertion after 4-8 weeks after extraction, soft tissue healing; type-3 protocol, early-delayed implant, insertion after 12-16 weeks, partial healing of the alveolar bone component; and type-4 protocol, late implant, insertion after six months, complete healing of the alveolar bone component [4].
The type-1 protocol is a predictable treatment modality with success rates comparable to the type-4 technique [5][6][7][8].This protocol brings several advantages, such as shorter procedures, reduced number of procedures, reduced vertical and horizontal resorption, and ideal gingival tissue esthetics [9][10][11].The surgical criteria advocated for type-1 implants are an intact facial bone wall with a thick phenotype (greater than 1 mm), thick gingival biotype, absence of acute infection, and apical and palatal bone volume suitable for implant placement with sufficient primary stability [12].
As a result of post-extraction implant insertion into the socket, a gap is formed between the inner surface of the buccal cortical plate and the implant, named the jumping gap.Management of the gap is a critical decision for the clinician, who must choose to fill it with a graft or leave it clear with the blood clot alone [13].In the 1990s, guided bone regeneration (GBR) was introduced, and alternatives were included, including using different grafts associated with a membrane placement [13].The GBR technique has been increasingly indicated in type-1 (immediate implant) rehabilitation treatments claiming the purpose to compensate for volumetric changes in hard and soft tissues by using autogenous bone tissue grafts, deproteinized bovine bone mineral (DBBM) as fillers, and connective tissue grafts (CTG) and xenogeneic collagen grafts for post-placement alveolus closure [14].
Buser et al. [9] argued that the implant should be placed 2 mm from the inner surface of the buccal cortical plate to facilitate appropriate gap filling with the bone graft.Preclinical studies suggest that a smaller gap results in greater vertical resorption of the cortical bone [9].The use of xenogeneic collagen material and a connective tissue graft to seal the socket and promote increased peri-implant keratinized mucosal volume is also well documented in the literature [15].The xenogeneic resorbable matrix provides advantages such as faster healing and fewer surgeries since no surgical procedure is required to harvest the connective tissue graft [16,17].In addition, DBBM placed in the marginal gap area reduces the amount of horizontal and vertical bone resorption associated with type-1 implant treatment [16].
It shows that a 4-walled defect is more favorable and presents reduced evidence of post-extraction ridge resorption because of the capability of containing the graft and greater effective capacity to incorporate the graft material [17].Buser et al. [9] concluded that GBR surgical techniques are indeed effective in promoting bone filling and partial or complete resolution of cortical defects; they are more successful when associated with type-1 and -2 implants than late implants [12].Therefore, there is a lack of uniformity about using or not tissue graft associated with IIP, and the type utilized if applicable.Thus, the objective of this systematic study was to review the literature in order to evaluate the efficacy of hard and/or soft tissue grafts associated with type-1 implants on healing and treatment outcomes.The null hypothesis was that the use of any graft material did not change or improve the healing process and esthetic result.The primary outcome variables were implant survival rate, pocket depth, marginal peri-implant recession, bone loss, bone thickness (volumetric change), interproximal bone level, mesial and distal papilla migration, and radiographic evaluation.The secondary parameters were Pink Esthetic Score (PES), vertical distance from implant shoulder and bone, Visual Analogue Score (VAS), Implant Stability Quotient (ISQ), and biological complications (fistulas, pain, mucositis, and peri-implantitis).

Protocol and PICO Strategy
The protocol of this systematic study was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines [18,19] and registered in the PROSPERO platform (International Prospective Register of Systematic Reviews, www.prospero.org,accessed on 10 January 2024; CRD42023383620).
The PICO (Population, Intervention, Comparison, and Outcome) strategy was used as the research model.The following question was posed to formulate the hypothesis under study: "For patients who underwent extraction and immediate implant placement, what is the efficacy of using any type of graft (bone or soft tissue) compared to nongrafting regarding the peri-implant parameters?" Population (P): Patients with a hopeless maxillary/mandibular tooth in the posterior or anterior areas who have received a type-1 implant with or without hard and soft tissue grafting; Intervention (I): Type-1 implant placement with or without hard and soft tissue grafting; Comparison (C): Hard and/or soft tissue grafting and standard healing; Outcome (O): Soft and hard tissue response as measured with the Pink Esthetic Score (PES), midfacial mucosa height, marginal bone loss (MBL), papilla index (PI), linear buccal change, volumetric change, bleeding on probing (BOP), and plaque index.

Eligibility Criteria
The inclusion criteria established for this review were as follows: randomized clinical trials (RCTs) that enrolled a minimum of 20 patients, had a follow-up of at least six months, and were published in the English language; studies that evaluated the efficacy of hard and/or soft tissue grafts on peri-implant tissue healing in the anterior or posterior sites in the maxilla or mandible.
The exclusion criteria established were animal or in vitro studies; any type of review; cohort studies; randomized clinical trials published before 2012; studies that included patients with uncontrolled systemic disorder; and editorials, abstracts in Congress, case reports, and case series.

Search Strategy and Data Extraction
Two calibrated researchers (E.M.R. and T.B.) executed the search strategy independently on the MedLine/PubMed and Cochrane Database platforms using the English language, human studies, and publications made since 2012 as search filters.Any disputes were resolved via confrontation and discussion between the two reviewers.The interrater reliability (Cohen's kappa coefficient, κ) was performed to verify the degree of agreement between evaluators.
The bibliographic search consisted of a combination of MeSH terms and free-text words combined through Boolean Operators (AND or OR).The keywords used were the following: (1)  Data were extracted based on the general study characteristics, population characteristics, graft, and implant technique characteristics.Any discrepancy was solved with discussion and collaboration.The data were collected in predefined tables: general information, including study design, year of publication, number of patients, and patient information; information related to implant surgery and type of graft, including number of implants, implant location in the mouth, type of graft for both groups, follow-up, and follow-up intervals; information related to the surgical protocol; information related with the studies outcome variables; main outcomes: Pink Esthetic Score (PES), midfacial mucosa height, marginal bone loss (MBL), papilla index (PI), linear buccal change, and volumetric change; and secondary outcomes, including bleeding on probing (BoP) and plaque index.

Quality Assessment and Risk of Bias
The quality of the study was independently assessed by two reviewers (T.B. and E.M.R.).The risk of bias for RCTs was performed by using a revised Cochrane risk-ofbias tool for randomized trials (RoB2) [20].The included parameters addressed with the tool (RoB2) were the following: the randomization process, deviation from intended interventions, missing outcome data, outcome measure, and selection of reported outcomes.If all parameters were filled with low risk (green) or up until there were two unclear (yellow), the overall result was Low Risk of Bias (green).For results with only one high risk (red) and up to two unclear (yellow), the result was Moderate Risk of Bias.Whereas, if filled with 2 or more High Risk (red) and/or more than 2 unclear risks (yellow), the overall result was High Risk of Bias.
A meta-analysis gathered the studies according to the similar analysis performed.A forest plot was developed using the random effect model to evaluate the effect size measures of standardized mean differences (95% confidence interval).Heterogeneity analysis was performed using Cochran's Q test and Higgins' I 2 , to verify if the existence of heterogeneity was the manifestation of differences between studies in relation to effect estimation.Percentages for I 2 of 0-40%, 41-75%, and 76-100% of the mean were considered, respectively, as low, medium, and high heterogeneity.All statistical analyses were performed using the software Review Manager (v.5.4).

Results
The initial electronic search identified 258 articles.Duplicate and triplicate articles were removed.The titles and abstracts of the potentially eligible articles concerning hard and soft tissue grafts in immediate implant placement (IIP) were carefully reviewed for eligibility.Two hundred forty-four publications were excluded, resulting in 14 articles (κ = 0.83).They were added to two hand-searched items, resulting in 16 articles chosen by title and abstract.The reasons for exclusion were studies not specific to dentistry (involved bone grafts in general surgery).Finally, the remaining 16 articles were examined via fulltext evaluation.Nine articles were excluded (κ = 0.98).The reasons for the exclusion were as follows: (1) dental techniques did not meet the chosen criteria for the study and (2) inability to access the article.Finally, nine articles were included in the study [21][22][23][24][25][26][27][28][29].The flow chart of the screening process is shown in Figure 1.

Study Characteristics
The characteristics of the included studies are described in Tables 1-5.Nine randomized clinical trials were analyzed with a total of 403 patients and 425 implants that we divided into three groups: bone graft (75 patients and 75 implants inserted), bone graft and membrane (213 patients and 235 implants inserted), and without bone graft (115 patients and 115 implants inserted).Regarding gender (Table 1), data were extracted only from seven out of the nine articles, totaling 156 men and 175 women [21][22][23][24][25]27,28].

Study Characteristics
The characteristics of the included studies are described in Tables 1-5.Nine randomized clinical trials were analyzed with a total of 403 patients and 425 implants that we divided into three groups: bone graft (75 patients and 75 implants inserted), bone graft and membrane (213 patients and 235 implants inserted), and without bone graft (115 patients and 115 implants inserted).Regarding gender (Table 1), data were extracted only from seven out of the nine articles, totaling 156 men and 175 women [21][22][23][24][25]27,28].

Author Surgical Protocol
Elaskary et al. [21] Atraumatic tooth extraction and the VST protocol.Then, a cortical membrane shield was made of heterologous origin and introduced through the tunnel apically.Group I: using the graft Group II: not using the graft.

Naji et al. [22]
For group I and II a full thickness flap.The junction gap was filled.
Group II was treated without bone graft or membrane.Group III healing was free.
Atef et al. [23] Test Group: the socket shield technique.Control Group: atraumatic extraction following implant placement; the junction gap was filled with bovine cancellous xenograft.
A piece of a collagen plug was placed to close the entrance of the extraction socket in both groups.
Mastrangelo et al. [24] Tooth extraction with mucoperiosteal flap.The immediate implant was inserted.Group A: graft and barrier healing.Group B: no graft and barrier.
DZ Group: the bone graft filled the junction gap to wall up to the free gingival margin.
BCG Group: the bone graft filled the junction gap; the graft was packed just reaching the buccal bone crestal level.
The junction gap was filled with AB or BBGM graft.
The graft was additionally covered with a platelet-rich fibrin (PRF) membrane.

Li et al. [27]
Tooth extraction with a mucoperiosteal flap.Immediate implant was inserted.
The junction gap was filled with a graft and injectable PRF and membrane barrier for healing.
Van Nimwegen et al. [28] Atraumatic flapless extraction technique.The junction gap was filled with xenograft inorganic bovine before the insertion of the immediate implant.In the test group, a connective autogenous graft was utilized.Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].

Bone Grafting versus Extractive Technique without Bone Grafting
Four studies [21][22][23][24] compared the use of a bone graft and various extraction techniques without a bone graft.Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were p posterior area [24,26,27], whereas, in two RCTs, implants were placed in the a including premolars [25,28].Regarding the arch, one RCT studied implants p mandible (number of implants = 43) [27]; on the other hand, three articles plac in the maxilla (numbers of implants = 186) [24,25,28].For the other included st not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six 23,25,28,29].Regarding periodontal status, untreated/uncontrolled periodo was an exclusion criterion in three studies [23,27,28].No adverse effects we related to smoking or periodontal disease.For the alveolar bone condition, an bone wall was considered as an inclusion criterion in four articles [22,23,25,28

Bone Grafting versus Extractive Technique without Bone Grafting
Four studies [21][22][23][24] compared the use of a bone graft and various extr niques without a bone graft.Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].
Current smoking habit was considered as an exclusion criterion in s 23,25,28,29].Regarding periodontal status, untreated/uncontrolled perio was an exclusion criterion in three studies [23,27,28].No adverse effects related to smoking or periodontal disease.For the alveolar bone condition, a bone wall was considered as an inclusion criterion in four articles [22,23,25
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].

Bone Grafting versus Extractive Technique without Bone Grafting
Four studies [21][22][23][24] compared the use of a bone graft and various extraction techniques without a bone graft.Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were p posterior area [24,26,27], whereas, in two RCTs, implants were placed in the a including premolars [25,28].Regarding the arch, one RCT studied implants p mandible (number of implants = 43) [27]; on the other hand, three articles plac in the maxilla (numbers of implants = 186) [24,25,28].For the other included st not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six 23,25,28,29].Regarding periodontal status, untreated/uncontrolled periodo was an exclusion criterion in three studies [23,27,28].No adverse effects we related to smoking or periodontal disease.For the alveolar bone condition, an bone wall was considered as an inclusion criterion in four articles [22,23,25,28

Bone Grafting versus Extractive Technique without Bone Grafting
Four studies [21][22][23][24] compared the use of a bone graft and various extr niques without a bone graft.Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].
Current smoking habit was considered as an exclusion criterion in s 23,25,28,29].Regarding periodontal status, untreated/uncontrolled perio was an exclusion criterion in three studies [23,27,28].No adverse effects related to smoking or periodontal disease.For the alveolar bone condition, a bone wall was considered as an inclusion criterion in four articles [22,23,25
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].

Bone Grafting versus Extractive Technique without Bone Grafting
Four studies [21][22][23][24] compared the use of a bone graft and various extraction techniques without a bone graft.Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were p posterior area [24,26,27], whereas, in two RCTs, implants were placed in the a including premolars [25,28].Regarding the arch, one RCT studied implants p mandible (number of implants = 43) [27]; on the other hand, three articles plac in the maxilla (numbers of implants = 186) [24,25,28].For the other included st not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six 23,25,28,29].Regarding periodontal status, untreated/uncontrolled periodo was an exclusion criterion in three studies [23,27,28].No adverse effects we related to smoking or periodontal disease.For the alveolar bone condition, an bone wall was considered as an inclusion criterion in four articles [22,23,25,28

Bone Grafting versus Extractive Technique without Bone Grafting
Four studies [21][22][23][24] compared the use of a bone graft and various extr niques without a bone graft.Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].
Current smoking habit was considered as an exclusion criterion in s 23,25,28,29].Regarding periodontal status, untreated/uncontrolled perio was an exclusion criterion in three studies [23,27,28].No adverse effects related to smoking or periodontal disease.For the alveolar bone condition, a bone wall was considered as an inclusion criterion in four articles [22,23,25

Bone Grafting versus Extractive Techn
Four studies [21][22][23][24] compared the use niques without a bone graft.Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.

Articles
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].

Bone Grafting versus Extractive Technique without Bone Grafting
Four studies [21][22][23][24] compared the use of a bone graft and various extraction techniques without a bone graft.Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were p posterior area [24,26,27], whereas, in two RCTs, implants were placed in the a including premolars [25,28].Regarding the arch, one RCT studied implants p mandible (number of implants = 43) [27]; on the other hand, three articles plac in the maxilla (numbers of implants = 186) [24,25,28].For the other included st not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six 23,25,28,29].Regarding periodontal status, untreated/uncontrolled periodo was an exclusion criterion in three studies [23,27,28].No adverse effects we related to smoking or periodontal disease.For the alveolar bone condition, an bone wall was considered as an inclusion criterion in four articles [22,23,25,28

Characteristics and Results of Interventions (
The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.

Characteristics and Results of Interventions (
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].
Current smoking habit was considered as an exclusion criterion in s 23,25,28,29].Regarding periodontal status, untreated/uncontrolled perio was an exclusion criterion in three studies [23,27,28].No adverse effects related to smoking or periodontal disease.For the alveolar bone condition, a bone wall was considered as an inclusion criterion in four articles [22,23,25

Bone Grafting versus Extractive Technique without Bone Grafting
Four studies [21][22][23][24] compared the use of a bone graft and various e niques without a bone graft.Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three stud posterior area [24,26,27], whereas, in two RCTs, implants including premolars [25,28].Regarding the arch, one RCT mandible (number of implants = 43) [27]; on the other han in the maxilla (numbers of implants = 186) [24,25,28].For t not possible to obtain this information because of the lack Current smoking habit was considered as an exclus 23,25,28,29].Regarding periodontal status, untreated/un was an exclusion criterion in three studies [23,27,28].No related to smoking or periodontal disease.For the alveolar bone wall was considered as an inclusion criterion in four

Bone Grafting versus Extractive Technique without
Four studies [21][22][23][24] compared the use of a bone gr niques without a bone graft.Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2 posterior area [24,26,27], whereas, in two RC including premolars [25,28].Regarding the mandible (number of implants = 43) [27]; on in the maxilla (numbers of implants = 186) [2 not possible to obtain this information beca Current smoking habit was considered 23,25,28,29].Regarding periodontal status, was an exclusion criterion in three studies related to smoking or periodontal disease.F bone wall was considered as an inclusion cr

Bone Grafting versus Extractive Techn
Four studies [21][22][23][24] compared the use niques without a bone graft.Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.

Characteristics and Results of Interventions (
The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.

Characteristics and Results of Interventions (
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were p posterior area [24,26,27], whereas, in two RCTs, implants were placed in the a including premolars [25,28].Regarding the arch, one RCT studied implants p mandible (number of implants = 43) [27]; on the other hand, three articles plac in the maxilla (numbers of implants = 186) [24,25,28].For the other included st not possible to obtain this information because of the lack of information.

Characteristics and Results of Interventions (Table 4)
Current smoking habit was considered as an exclusion criterion in six 23,25,28,29].Regarding periodontal status, untreated/uncontrolled periodo was an exclusion criterion in three studies [23,27,28].No adverse effects we related to smoking or periodontal disease.For the alveolar bone condition, an bone wall was considered as an inclusion criterion in four articles [22,23,25,28  Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.

Characteristics and Results of Interventions (Table 4)
Current smoking habit was considered as an exclusion criterion in s 23,25,28,29].Regarding periodontal status, untreated/uncontrolled perio was an exclusion criterion in three studies [23,27,28].No adverse effects related to smoking or periodontal disease.For the alveolar bone condition, a bone wall was considered as an inclusion criterion in four articles [22,23,25 Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three stud posterior area [24,26,27], whereas, in two RCTs, implants w including premolars [25,28].Regarding the arch, one RCT mandible (number of implants = 43) [27]; on the other han in the maxilla (numbers of implants = 186) [24,25,28].For t not possible to obtain this information because of the lack Current smoking habit was considered as an exclus 23,25,28,29].Regarding periodontal status, untreated/un was an exclusion criterion in three studies [23,27,28].No related to smoking or periodontal disease.For the alveolar bone wall was considered as an inclusion criterion in four Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2 posterior area [24,26,27], whereas, in two RC including premolars [25,28].Regarding the mandible (number of implants = 43) [27]; on in the maxilla (numbers of implants = 186) [2 not possible to obtain this information becau Current smoking habit was considered 23,25,28,29].Regarding periodontal status, was an exclusion criterion in three studies related to smoking or periodontal disease.Fo bone wall was considered as an inclusion cr Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.

Characteristics and Results of Interventions
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were p posterior area [24,26,27], whereas, in two RCTs, implants were placed in the a including premolars [25,28].Regarding the arch, one RCT studied implants p mandible (number of implants = 43) [27]; on the other hand, three articles plac in the maxilla (numbers of implants = 186) [24,25,28].For the other included st not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six 23,25,28,29].Regarding periodontal status, untreated/uncontrolled periodo was an exclusion criterion in three studies [23,27,28].No adverse effects we related to smoking or periodontal disease.For the alveolar bone condition, an bone wall was considered as an inclusion criterion in four articles [22,23,25,28

Deviations from
The Intended Interventions Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six 23,25,28,29].Regarding periodontal status, untreated/uncontrolled periodo  Noelken et al. [26] van Nimwegen et al. [28] Elaskary et al. [21] Mastrangelo et al. [24] Li et al. [27] Frizzera et al. [29] The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.

Characteristics and Results of Interventions (
The implant sites are detailed in Table 2.In three studies, implants were placed in the posterior area [24,26,27], whereas, in two RCTs, implants were placed in the anterior area, including premolars [25,28].Regarding the arch, one RCT studied implants placed in the mandible (number of implants = 43) [27]; on the other hand, three articles placed implants in the maxilla (numbers of implants = 186) [24,25,28].For the other included studies, it was not possible to obtain this information because of the lack of information.
Current smoking habit was considered as an exclusion criterion in six studies [21][22][23]25,28,29].Regarding periodontal status, untreated/uncontrolled periodontal disease was an exclusion criterion in three studies [23,27,28].No adverse effects were reported related to smoking or periodontal disease.For the alveolar bone condition, an intact buccal bone wall was considered as an inclusion criterion in four articles [22,23,25,28].

Alloplastic Graft with Membrane versus Extraction Technique
The authors reported a 100% implant success rate at the sixth-month follow-up.They found a significant reduction in the buccal bone plate at the 6-month observation in the flap extraction group without a graft, compared with the flap and flapless extraction group with a graft.No significant differences between the flap extraction with graft and flapless groups were found: the group with a graft presented changes of −0.37 ± 0.09 mm, the flap group −0.91 ± 0.54 mm, and the flapless group −0.24 ± 0.11 mm.
Li et al. [29] reported the failure of two implants but did not mention which group they belonged to.The authors found no significant difference in the ISQ of implant stability and marginal bone resorption between the two groups at 1 year.According to the authors, particulate derived from granulation of the extracted tooth appears to be a viable alternative for the GBR technique in immediate implant placement.The authors reported the failure of two implants (one per group), with a 1-year survival rate of 96.7%.Tissue volume loss was found in both groups, but no significant difference was identified between the two groups.However, a statistically significant difference was identified at the buccal mucosa level at 1 year in favor of the xenograft + autograft + CTG treated group.The group with the soft tissue graft presented a mean increase of +0.20 ± 0.70 mm compared with a mean loss of −0.48 ± 1.13 mm in the group treated without using the CTG.This may be translated to a nonsignificant difference in terms of soft tissue volume reduction in the post-extraction phase but to greater tissue stability when using a connective tissue membrane.No significant difference was found between the two groups in total PES, PD, and Plaque Index at 1-year follow-up.The authors reported a 100% success rate of the inserted implants.The total PES found no significant differences between the groups at 6 months and 1 year.Nevertheless, they stated that one of the PES scores, the alveolar process, was significantly better in the group treated without a membrane or CTG.In contrast, the PES score regarding gingival recession favors the group treated with graft and CTG.The authors found no significant differences in bone thickness and bone resorption between the three groups at 6 months and 1 year after implant insertion.[28].The authors found no significant difference in using a xenogeneic graft with or without a membrane.

Facial Bone Thickness at 12 Months
Facial bone thickness was studied by Naji et al. [22] and Elaskary et al. [21].The authors found better yields in the graft-treated and flapless groups.

Quality Assessment and Risk of Bias
The risk of bias was evaluated by using a revised Cochrane risk-of-bias tool for randomized trials (RoB2).Four studies had low risk of bias, four had moderate risk of bias, and one had high risk of bias (Table 5).

Meta-Analysis
Given the results of Figures 2 and 3, Cochran's Q had a p-value of 0.15 and I 2 = 46%; then, it was possible to verify a medium level of heterogeneity for the mid-facial mucosa level analysis.The forest plot shows that the meta-analysis effect of 0.79 (95% CI [0.18; 1.40]) was statistically significant (p = 0.01).There was a tendency to favor the experimental group in all articles included for this analysis.
domized trials (RoB2).Four studies had low risk of bias, four had moderate risk of bias, and one had high risk of bias (Table 5).

Meta-Analysis
Given the results of Figures 2 and 3, Cochran s Q had a p-value of 0.15 and I 2 = 46%; then, it was possible to verify a medium level of heterogeneity for the mid-facial mucosa level analysis.The forest plot shows that the meta-analysis effect of 0.79 (95% CI [0.18; 1.40]) was statistically significant (p = 0.01).There was a tendency to favor the experimental group in all articles included for this analysis.Considering the results of Figures 4 and 5, Cochran s Q had a p-value of 0.16 and I 2 = 45%; thus, it was possible to verify a medium level of heterogeneity among studies regarding total PES.The forest plot shows no significant differences between studies (p =

Quality Assessment and Risk of Bias
The risk of bias was evaluated by using a revised Cochrane risk-of-bias tool for randomized trials (RoB2).Four studies had low risk of bias, four had moderate risk of bias, and one had high risk of bias (Table 5).

Meta-Analysis
Given the results of Figures 2 and 3, Cochran s Q had a p-value of 0.15 and I 2 = 46%; then, it was possible to verify a medium level of heterogeneity for the mid-facial mucosa level analysis.The forest plot shows that the meta-analysis effect of 0.79 (95% CI [0.18; 1.40]) was statistically significant (p = 0.01).There was a tendency to favor the experimental group in all articles included for this analysis.Considering the results of Figures 4 and 5, Cochran s Q had a p-value of 0.16 and I 2 = 45%; thus, it was possible to verify a medium level of heterogeneity among studies regarding total PES.The forest plot shows no significant differences between studies (p =    study had a higher weight (97.4%) in this analysis.The forest plot shows that the metaanalysis effect of 0.37 (95% CI [0.25;0.50])was statistically significant (p < 0.00001).

Discussion
The aim of this systematic study was to evaluate the efficacy of hard and/or soft tissue grafts associated with type-1 implants (IIP) on healing and treatment outcomes to provide a more predictable result.Our study included only RCTs that evaluated IIP with at least

Discussion
The aim of this systematic study was to evaluate the efficacy of hard and/or soft tissue grafts associated with type-1 implants (IIP) on healing and treatment outcomes to provide a more predictable result.Our study included only RCTs that evaluated IIP with at least one group using hard and/or soft tissue grafts.
Buser et al. [9,30] identified some factors that may increase the risk of esthetic predictability in IIP cases: (1) thin gingival biotype, (2) thin buccal bone wall, and (3) implant surgical procedure by itself.Also, Buser et al. [30] showed a greater risk of having a 1 mm gingival recession and greater variability in esthetic results when using the immediate implant technique.This was also stated by Bakkali et al. [31], who argued that there is less esthetic predictability using this approach.On the other hand, Siqueira et al. [32] showed a case report of IIP combined with CTG, demineralized bovine bone mineral with 10% collagen, and immediate provisional crown adjusted intra-and extra-orally (establishing the ideal critical and subcritical contour), with high tissue stability after 4 years.Among the included studies, only two considered and used the CTG associated with IIP [28,29], with improved clinical results compared to the control group.Even though it has been shown that a membrane promotes bone neoformation by positively influencing bone remodeling as a scaffold between implant and bone [33], two studies [22,24] that considered the utilization of collagen membranes did not have significant results.
Borges et al. [34] pointed out that a buccal bone ridge thinner than 1 mm is the primary determinant of buccal tissue reduction at 1-year post-treatment with immediate dental implants.The authors showed that pretreatment of this anatomic condition is important in cases where the individual is also diagnosed with a thin gingival biotype [34].Due to this concern (the presence of buccal bone ridge thinner than 1 mm), several authors have advocated using bone grafts, which could significantly reduce peri-implant tissue reduction [34][35][36].Moreover, bone grafts contributed to horizontal bone preservation and soft tissue stability at the midfacial aspect of immediate implants, which should be considered as an adjunct to IIP in clinical practice [7].Elaskary et al. [21] reported improved clinical yield regarding the buccal bone ridge when the post-extraction gap was treated with a graft.The experimental group, treated with a VST technique and a graft, presented a facial bone thickness of 2.95 ± 0.97 mm at the mid-level and 3.75 ± 1.30 mm at the apical level of the alveolar ridge, in contrast with the control group (without a graft) which presented values for the buccal bone of 1.82 ± 0.64 mm and 2.03 ± 0.81 mm, respectively.Therefore, the results must be carefully interpreted due to the limited number of studies included and the heterogeneity found.
It is essential to highlight that if the remnant post-extraction buccal gap size exceeds 1.5 mm, it might achieve incomplete bone regeneration if left to spontaneous heal [37].This fact agrees with Naji et al.'s results [22], which indicated that the group with the flap technique and a graft had better buccal bone maintenance (buccal bone changes of −0.37 ± 0.09 mm) compared to the group with a flap without a graft (buccal bone changes of −0.91 ± 0.54 mm).The same authors also advocated that, if possible, applying the flapless technique can substantially improve the tissue healing performance compared to the use of a flap, preventing or reducing the buccal bone resorption; this can be explained by a reduction in the breaking of the local vascularization; the blood perfusion for the buccal bone ridge comes essentially from the periodontal ligaments, periosteum, and bone marrow [38].In addition, they reported better results using a membrane than first intention closure, which agrees with a systematic review [31] that supported using bone grafts to reduce the buccal bone wall resorption after tooth extraction.However, the results presented in our study must be carefully interpreted because of the small sample size present in some of the included articles and the moderate/high risk of bias observed.
Clearly, esthetic factors are influenced by the presence or absence of a substantial buccal bone volume.Without a sufficient buccal bone plate, marginal bone resorption will result in volumetric alteration of the peri-implant soft tissue [39].This theory entirely agrees with Guarnieri et al.'s [10] arguments, which include the believe that bone loss and the likelihood of soft tissue volume reduction are directly proportional: greater bone loss will likely cause a gingival recession.Fernandes and collaborators [40] stated that the predictability of these outcomes in IIP is related to correct patient selection criteria.However, they also argued that there is a lack of objectivity in the methods used in studies to evaluate esthetic outcomes, which often depend on the observer, reducing reproducibility among different observers and studies [40].Wanis et al.'s study [25] agrees with these findings; they claimed that both groups revealed a PES value between 10 and 12, which is considered a good result.In contrast, Abd-Elrahman et al. [41], who observed similar groups to those within Wanis et al.'s [25] study, but without the use of bone grafts, reported a significantly lower PES at 6-month follow-up (8.85 ± 1.81).Wanis et al. [25] reported that using a surgical technique without a graft at the post-extraction buccal gap was responsible for the reduced total PES value; they stated that no real prevention of the buccal bone loss was observed in either of the groups at 6 and 12 months after implant insertion: −0.88 mm ± 0.41 in the dual-zone technique group and −1.08 mm ± 0.28 in the group with the graft alone.
The literature suggests some variability in terms of the mean MBL associated with type-1 implants with various surgical techniques and grafts: Siqueira et al. [42] reported a −0.66 ± 0.38 mm mean of marginal bone reduction while Pardal-Pelaez et al. [43] reported −0.42 ± 0.78 mm and Mazzocchi et al. [44] reported −0.48 ± 0.76 mm.These slight changes could be due to the different assessment techniques, which are unequal and operator-dependent [25].Sanz et al. [45] had previously reported a significant reduction in MBL when IIP was associated with using a bone graft: −1.1 mm (graft group) compared to −1.6 mm in the non-graft group.However, several authors consider the intact buccal bone plate and gingival biotype beyond other factors, such as the flapless technique and the distance between implant shoulder and cortical bone, as determinants for the buccal bone healing at IIP sites, regardless of the presence of large gaps and the use of different grafts [46].Furthermore, Elaskary et al. [21] argued that the first six months after surgery is the most critical period concerning post-extraction bone resorption.This is also supported by Borges et al. [34] and Lops et al. [47].
In addition, the literature has limitations regarding studies on compromised postextraction sockets [11].Most studies report positive data for IIP techniques in fresh and intact sockets [29,48,49] but strongly question such outcomes when the technique is used in damaged/compromised post-extraction ones [50][51][52][53].Elaskary et al. [21] argued that when faced with such eventuality, the clinician should always opt for bone regeneration with a membrane in conjunction with immediate implantation to achieve better esthetic and functional results.These authors reported better results when the xenograft is combined with a CTG (from the patient's palate).They also reported a higher PES score regarding the level of marginal mucosal tissue [21].This fact was also highlighted by Van Nimwegen et al. [28], who hypothesized the association between a xenograft and CTG might provide greater stability to peri-implant tissues, namely at the marginal mucosal level.Nevertheless, the authors concluded that using a CTG associated with a xenogeneic bone graft may not counteract the volumetric tissue changes after IIP.The data presented did not show any significant differences in terms of volumetric reduction of the soft tissue, but it had positive effects on peri-implant marginal mucosa stability one year after treatment: the test group presented an average increase of 0.20 ± 0.70 mm compared to an average loss of −0.48 ± 1.13 mm in the control group [28].They also reported significantly higher marginal gingival PES results than those without connective tissue grafts, even though total PES values showed no significant statistical differences between the two groups.Then, the authors concluded that CTG should be associated with IIP to reduce the possibility of asymmetry between peri-implant soft tissue and adjacent teeth [28].
The limitations of this review can be assigned to different items.We included only articles published in English; given the relatively recent nature of these techniques, the literature is still sparse, and we only included nine RCTs, following the inclusion criteria initially established.In addition, one of the databases consulted had no search results.Also, for the selected articles, after careful independent analysis by the two independent researchers (EMR and TB), we found considerable variability in terms of the chosen variables included in the studies and evaluation techniques that were not always objective, repeatable, and comparable; some articles had a small sample size, the presence of heterogeneity was found, and moderate/high RoB was observed, which suggests a careful interpretation of the data obtained.These reasons explain why we were able to conduct a meta-analysis of a low number of variables, selecting a total of five articles, which were divided among three comparable parameters.Moreover, because of the variability of the evaluation techniques and variables, it was necessary to work on interpretation and equivalence to summarize the data into clear and universal parameters that could be used to group the highest number of publications.

Conclusions
Within the limitations of this study, it was possible to conclude that using bone and soft tissue grafting techniques associated with IIP, even though they are not fundamental, were a valuable resource to prevent significant tissue reduction, reaching greater bone stability and higher levels in the Pink Esthetic Score (PES) and Visual Analogue Score (VAS).Results also may depend on the professional's surgical and clinical ability/experience.In addition, the use of CTG combined with a xenogeneic bone graft brought advantages to the mid-facial mucosa position around immediate implants.It is important to state that standardized clinical assessment techniques and objective criteria are needed for comparisons in future studies.

Figure 1 .
Figure 1.The flow diagram for the selection process is according to the PRISMA report (Preferred Reporting Items for Systematic Reviews and Meta-Analyses).

Figure 1 .
Figure 1.The flow diagram for the selection process is according to the PRISMA report (Preferred Reporting Items for Systematic Reviews and Meta-Analyses).

Table 5 .
Overall risk-of-bias assessment using the Cochrane risk-of-bias 2 (RoB2) to

Table 5 .
Overall risk-of-bias assessment using the Cochrane risk

Figure 3 .
Figure 3. Funnel plot for the mid-facial mucosa level (12 months).Considering the results of Figures 4 and 5, Cochran's Q had a p-value of 0.16 and I 2 = 45%; thus, it was possible to verify a medium level of heterogeneity among studies regarding total PES.The forest plot shows no significant differences between studies (p = 0.91), although Frizzera et al. [29] presented favoring toward the experimental group, and Wanis et al. [25] toward the control group.0.91), although Frizzera et al. [29] presented favoring toward the experimental group, and Wanis et al. [25] toward the control group.

Figures 6
Figures6 and 7show homogeneity (I 2 = 0%) among the facial bone thickness analysis studies.The Cochran's Q analysis had a p-value of 0.48, presenting no statistical differences between the studies evaluated, with both favoring the experimental group.Naji et al.'s [22]

Figures 6
Figures 6 and 7 show homogeneity (I 2 = 0%) among the facial bone thickness analysis studies.The Cochran s Q analysis had a p-value of 0.48, presenting no statistical differences between the studies evaluated, with both favoring the experimental group.Naji et al. s [22] study had a higher weight (97.4%) in this analysis.The forest plot shows that the meta-analysis effect of 0.37 (95% CI [0.25;0.50])was statistically significant (p < 0.00001).

Figures 6
Figures6 and 7show homogeneity (I 2 = 0%) among the facial bone thickness analysis studies.The Cochran s Q analysis had a p-value of 0.48, presenting no statistical differences between the studies evaluated, with both favoring the experimental group.Naji et  al. s [22]  study had a higher weight (97.4%) in this analysis.The forest plot shows that the meta-analysis effect of 0.37 (95% CI [0.25;0.50])was statistically significant (p < 0.00001).
PubMed/Medline: Dental implant [Mesh] OR dental implantation [Mesh] AND immediate implant placement [text word] AND graft [Mesh] AND bone [Mesh] OR bone graft [text word] OR buccal gap [text word]; filters: RCT-studies; 10 years studies; Human studies; English studies.(2) Cochrane: Dental Implant [Mesh] OR dental implantation [Mesh] AND immediate implant placement [text word] AND graft [Mesh] AND bone [Mesh] OR bone graft [text word] OR buccal gap [text word]; filter: None.

Table 2 .
Graft and implant information.

Table 4 .
Clinical outcomes of selected studies.

Randomization Process Deviations from The Intended In- terventions Missing Outcome Data Measurement of the Outcome Selection of the Reported Result Overall
[23] et al. [22]Atef er al.[23]Wanis et al.[25]

Randomization Process Deviations from The Intended In- terventions Missing Outcome Data Measurement of the Outcome Selection of the Reported Result Overall
[26]ken et al.[26] J. Clin.Med.2024, 13, x FOR PEER REVIEW 14 of 24

Table 4 ) 3
.2.1.Bone Grafting versus Extractive Technique without Bone Grafting Four studies [21-24] compared the use of a bone graft and various extraction techniques without a bone graft.. Med.2024, 13, x FOR PEER REVIEW 14 of 24

Table 4 ) 3
.2.1.Bone Grafting versus Extractive Technique without Bone Grafting Four studies [21-24] compared the use of a bone graft and various extraction techniques without a bone graft.J. Clin.Med.2024, 13, x FOR PEER REVIEW 14 of 24

Table 5 .
Overall risk-of-bias assessment using the Cochrane risk

Table 5 .
Overall risk-of-bias assessment using th

Randomization Process Deviations from The Intended In- terventions Missing Outcome Data Measurement of the Outcome Selection of the Reported Result Overall
[23] et al. [22]Atef er al.[23]Wanis et al.[25]

Table 4 ) 3
.2.1.Bone Grafting versus Extractive Technique without Bone Grafting Four studies [21-24] compared the use of a bone graft and various extraction tech-.Med.2024, 13, x FOR PEER REVIEW 14 of 24

Table 4 ) 3
.2.1.Bone Grafting versus Extractive Technique without Bone Grafting Four studies [21-24] compared the use of a bone graft and various extraction tech-J.Clin.Med.2024, 13, x FOR PEER REVIEW 14 of 24

Randomization Process Deviations from The Intended In- terventions Missing Outcome Data Measurement of the Outcome Selection of the Reported Result Overall
[23] et al. [22]Atef er al.[23]Wanis et al.[25]

Table 4 ) 3
.2.1.Bone Grafting versus Extractive Technique without Bone Grafting Four studies [21-24] compared the use of a bone graft and various extraction tech-J.Clin.Med.2024, 13, x FOR PEER REVIEW

Table 5 .
Overall risk-of-bias assessment using

Randomization Process Deviations from The Intended In- terventions Missing Outcome Data Measurement of the Outcome Selection of the Reported Result Overall
[23] et al. [22]Atef er al.[23]Wanis et al.[25]

Randomization Process Deviations from The Intended In- terventions Missing Outcome Data Measurement of the Outcome Selection of the Reported Result Overall
[23] et al. [22]Atef er al.[23]Wanis et al.[25] J. Clin.Med.2024, 13, x FOR PEER REVIEW 14 of 24

Table 5 .
Overall risk-of-bias assessment using

Table 5 .
Overall risk-of-bias assessment using th