Prosthesis

Background/Objective: Changes in limb volume affect prosthetic socket fit and limb health, which in turn affects the comfort, stability, and usability of a prosthesis. The objective of this research was to identify and evaluate residual limb fluid volume metrics that could be used to identify the need for a prosthetic socket modification or replacement. Methods: A prospective observational study was conducted with transtibial prosthesis users undergoing socket modification or replacement. Participants performed a morning and afternoon 20 min structured activity protocol and self-reported their average socket comfort and other health outcomes before and after their socket was modified or replaced. Limb fluid volume changes across the protocol were recorded using bioimpedance analysis. Results: Anterior region residual limb fluid volume loss was low when the socket comfort score was high. Participants with ESCS_ave increases of ≥2 points pre- to post-modification experienced less limb fluid volume loss post-modification minus pre-modification (mean +0.6%) compared to participants with ESCS_ave increases of <2 points (mean −0.9%) (p = 0.0002). Conclusions: The percentage of fluid volume in the anterior limb may be a useful quantitative metric to explore for the application of bioimpedance monitoring in clinical care, helping to identify when sufficient change has occurred such that a new socket is warranted. Full article

Objectives: Traditional 2D cell cultures on flat surfaces fail to replicate 3D environments, affecting cellular morphology and function. Various 3D techniques (e.g., spheroids, organoids, organs-on-chips, 3D bioprinting) have been used for disease modelling and drug testing, but their application in hard tissues remains challenging. This study aimed to develop a biocompatible 3D culture method for bone tissue organoids using human bone marrow-derived stem cells (hBMSCs) and hydrogels. Methods: hBMSCs were isolated from human jawbone marrow. The control group was cultured under 2D conditions, whereas the experimental group was cultured in a 3D hydrogel environment. In vitro analyses, including flow cytometry and RNA sequencing, were performed. Quantitative data were statistically analysed at a 0.05 level of significance. Results: hBMSCs cultured in 3D hydrogel conditions indicated enhanced reproducibility, increased cell viability, and significant osteogenic differentiation. Genes such as MMP-13, LPL, and SP7 showed substantially higher expression in 3D cultures, with protein-level confirmation by Western blot. These findings suggest that 3D culture more effectively supports the natural growth and differentiation of hBMSCs. Conclusions: Culturing hBMSCs in a 3D environment more closely mimics in vivo conditions, thus promoting the expression and activity of critical proteins involved in hBMSC differentiation. Full article

Background: Nanomaterial-based biosensors represent a transformative advancement in oral health diagnostics and therapeutics, offering superior sensitivity and selectivity for early disease detection compared to conventional methods. Their applications span prosthetic dentistry, where they enable the precise monitoring of dental implants, and theranostics for conditions such as dental caries, oral cancers, and periodontal diseases. These innovations promise to enhance proactive oral healthcare by integrating detection, treatment, and preventive strategies. Objectives: This review comprehensively examines the role of nanomaterial-based biosensors in dental theranostics, with a focus on prosthetic applications. It emphasizes their utility in dental implant surveillance, the early identification of prosthesis-related complications, and their broader implications for personalized treatment paradigms. Methods: A systematic literature search was conducted across PubMed, Scopus, and Web of Science for studies published between 2010 and early 2025. Keywords included combinations of “nanomaterials”, “biosensors”, “dentistry”, “oral health”, “diagnostics”, “therapeutics”, and “theranostics”. Articles were selected based on their relevance to nanomaterial applications in dental biosensors and their clinical translation. Results: The review identified diverse classes of nanomaterials—such as metallic nanoparticles, carbon-based structures, and quantum dots—whose unique physicochemical properties enhance biosensor performance. Key advancements include the ultra-sensitive detection of biomarkers in saliva and gingival crevicular fluid, the real-time monitoring of peri-implant inflammatory markers, and cost-effective diagnostic platforms. These systems demonstrate exceptional precision in detecting early-stage pathologies while improving operational efficiency in clinical settings. Conclusions: Nanomaterial-based biosensors hold significant promise for revolutionizing dental care through real-time implant monitoring and early complication detection. Despite challenges related to biocompatibility, scalable manufacturing, and rigorous clinical validation, these technologies may redefine oral healthcare by extending prosthetic device longevity, enabling personalized interventions, and reducing long-term treatment costs. Future research must address translational barriers to fully harness their potential in improving diagnostic accuracy and therapeutic outcomes. Full article

Introduction: Intertrochanteric femoral fractures (IFFs) are the most common traumatic injuries in elderly people and significantly impact the patient’s health status. The current evidence indicates that short intramedullary nails may be a better choice than dynamic hip screws in IFF management, being less invasive and biomechanically superior, providing a buttress to limit fracture collapse. On the other hand, an unstable fracture may collapse even after adequate reduction and fixation. This paper aims to describe the surgical complexity of the nail-to-total hip arthroplasty (THA) conversion, focusing on the restoration of normal hip geometry. Material and Methods: Patients referred to our level I trauma center with failed cephalomedullary nailing following IFFs and managed with the nail-to-THA conversion were retrospectively recruited. The anteroposterior postoperative pelvis radiographs were analyzed to establish whether the normal biomechanics of the involved hip were restored. The following radiographic parameters were recorded and compared to the contralateral unaffected side: hip offset, cervical–diaphyseal angle, and limb length discrepancy. Clinical assessment was performed using the following scores: the Harris hip score (HHS) and the visual analog scale for pain (VAS). The independent samples t-test and the Pearson correlation test were performed. The tests were two-tailed; a p < 0.05 was considered significant. Results: A total of 31 patients met the inclusion and exclusion criteria (10 males and 21 females; mean age: 76.2 years; range: 66–90 years) and were included in this study. The modes of trochanteric nail failure included the following: cut-out in 22 cases (70.97%), non-union in 4 cases (12.9%), peri-implant fracture in 1 case (3.23%), cut-through in 2 cases (6.45%), and femoral head avascular necrosis (HAN) in 2 cases (6.45%). Long stems were used in 21 patients out of 31 (67.74%), while dual-mobility cups were implanted in 24 patients out of 31 (77.41%). A significant mean neck shaft angle (NSA) increase (p < 0.001) and a significant mean femoral offset reduction (FO, p 0.001) compared to the contralateral hip were recorded; a mean limb length discrepancy (LLD) of 8.35 mm was observed. A significant correlation between HHS and ∆NSA (p = 0.01) and ∆FO (p = 0.003) was recorded. Conclusions: Conversion from a cephalomedullary nail to THA is a complex procedure that should be considered a revision surgery, rather than a primary surgery. Surgeons must be aware that normal hip geometry may not be obtained during this surgical procedure; thus, a patient undergoing the nail-to-THA conversion for intertrochanteric fixation failure may have an increased risk of implant-related complications. Full article

Background/Objective: Research indicates that sport is a useful avenue in rehabilitation for redeveloping identity for people with a limb amputation. However, the available research focusses on Paralympians or elite athletes with disabilities. By contrast, this study aimed to explore the experience of sport participation and identity in lay members of the public who had undergone limb amputation. Methods: Semi-structured interviews took place with nine people who had undergone amputation and participated in sport. The interviews were recorded, transcribed, and analysed using interpretative phenomenological analysis. Results: Four themes were developed from the data: (1) enabling a feeling of normality and equality; (2) becoming a better person; (3) belonging and connection; and (4) experiencing and responding to the gaze of others. The findings highlight the role of sport in facilitating personal growth through a desire to help and inspire others. Conclusions: Rehabilitation professionals involved in care following amputation could offer person-centred therapies to those who may be reluctant to participate in sport in a way that makes use of a person’s values and facilitates personal growth. Full article

Background/Objectives: Using chemical disinfectants to clean the base of heat-cured acrylic dentures has several negative effects, including toxicity. On the other hand, therapeutic herbs have fewer adverse effects. This study intended to determine how the antibacterial efficacy and the surface roughness of the heat-cured acrylic material used to fabricate dentures were affected by the use of Cordia myxa fruit (CMF) extract as a disinfection solution for dentures using the immersion technique. Methods: Heat-cured acrylic specimens were prepared (N = 110; 55 specimens) for each test; each group contained five specimens. Three CMF extract concentrations (50, 100, and 150 mg/mL) were made and examined for three immersion times (5, 10, and 15 min). The results were compared to the first control group, which used distilled water, and the second group, which used 2% glutaraldehyde for ten minutes, in accordance with the guidelines. One way analysis of variance ANOVA and Games–Howell post hoc test were employed in SPSS (Statistical Package for the Social Sciences) program for statistical analysis. Results: The results for the antibacterial test revealed that CMF solutions had a statistically significant difference in all test groups in comparison with the first control group and non-significant differences with (H p = 0.92; J p = 0.278; K p = 0.303) groups in comparison with the second control group (Glutaraldehyde 2%). For the surface roughness test, the effect was not statistically significant for all groups compared to the first and second control groups. Conclusions: It can be concluded that immersing the heat-cure acrylic samples in a solution of 100 mg/mL CMF extract for 15 min, and 150 mg/mL for 10 and 15 min, has an antibacterial effect similar to that of the Glutaraldehyde 2% antiseptic and no negative effect on surface roughness. Full article

Purpose: The aim of this study was to evaluate the color stability of 3D printed resin disks using spectral reflectance data obtained at different time periods after immersion in various staining solutions. The color stability of 3D-printed temporary crowns is clinically important, as it directly affects the esthetic outcome and patient satisfaction during the provisional phase of treatment. Materials and methods: Forty identical round disk specimens measuring 10 mm in diameter and 2 mm in thickness were fabricated using CAD/CAM 3D printing resin (shade B1). Half of the specimens (n = 20) were polished using an acrylic bur and medium pumice. The remaining specimens were unpolished (n = 20). Each group of disks was then immersed in one of the following immersion solutions: artificial saliva, black tea, carrot juice, and red wine. Color difference ΔE was evaluated using the spectrophotometer, a spectral reflectance instrument, at baseline, day 1, week 1, week 2 and week 3, against a white background. Comparisons between polished and unpolished disks at each time point were conducted using Mann–Whitney tests. Differences among the staining solutions at each time point for both polished and unpolished disks were analyzed using a one-way ANOVA with Tukey’s post hoc test. Results: Color difference ΔE was measured using the CIELAB formula. The mean ΔE values of each group were calculated. The greatest difference in color was observed in the unpolished and polished disks immersed in red wine. Polished disks showed less color difference when compared to unpolished disks. Significant differences in ΔE were detected between polished and unpolished disks immersed in red wine at week 1 (p = 0.0159), week 2 (p = 0.0079) and week 3 (p = 0.0079) and in carrot juice at week 3 (p = 0.0317). Conclusions: Immersion of 3D printed disks in different staining solutions caused detectable color difference in the tested materials, which was relative to the immersion duration and the staining solution used. The color of the 3D printed resins is influenced by the surface finishing, which may result in visually perceptible color differences. The color stability of 3D printied materials should be improved to provide long-term esthetics. Full article

Purpose: The aim of this study was to evaluate the long-term clinical results of two different implant–abutment connection types (screw-retained/Morse locking taper), marginal bone loss, and complications in prosthetic restorations. Materials and Methods: In 2017–2018, 579 implants and 242 implant-supported restorations applied to 137 patients were included in the study. Patients were recalled every six months, clinical evaluations were accomplished, and complications were recorded. When examining the distribution of prosthetic restorations by type, it was determined that 38 (15.70%) were single crowns, 136 (56.19%) were fixed partial cement-retained bridge restorations, 53 (21.90%) were fixed partial screw-retained bridge restorations, and 15 (6.19%) were overdenture prostheses. Findings: Overall, complications included eighteen (21.68%) retention losses, nineteen (22.89%) instances of screw loosening, twenty-one (25.30%) veneer ceramic fractures, three (3.61%) acrylic base fractures, fourteen (16.87%) cases of peri-implantitis, and eight (9.64%) implant losses. Conclusions: Differences in complication rates were observed between implants with different implant–abutment connection designs. While no significant differences were found regarding annual mesial and distal marginal bone loss for implants with conical locking connections, a significant difference was detected in those with screw-retained connections. In both implant groups, mesial and distal marginal bone loss progressed gradually over the follow-up period. Full article

Background: Total hip arthroplasty (THA) is a widely adopted surgical intervention for restoring mobility and reducing pain in patients with severe hip joint conditions, such as osteoporosis. However, traditional titanium implants often lead to stress shielding and subsequent bone resorption due to the mismatch in stiffness between the implant and bone. Objectives: This study computationally investigates the biomechanical performance of femoral implants made from composite materials, specifically polyether-ether-ketone (PEEK) and polylactic acid (PLA) reinforced with hydroxyapatite (HA), compared to conventional titanium stems. Methods: Using finite element (FE) modeling, physiological loading during walking was simulated, and the strain energy density (SED) was analyzed to assess stress distribution and the potential for stress shielding across different Gruen zones. Results: The results indicate that both the PEEK and PLA composites exhibited more physiological load transfer, particularly in Gruen zones 1 and 7, reducing stress shielding and supporting bone preservation. Conclusions: These findings suggest that PEEK and PLA composites may offer improved implant stability and bone integration. Despite highlighting the promise of biomimetic materials in orthopedics, this study is limited to computational analysis and requires experimental validation. It emphasizes the need for further investigation using patient-specific geometries and a variety of loading scenarios to confirm these benefits and optimize femoral implant design. Full article

Purpose: This study aimed to evaluate the load-bearing capacity of three different millable lithium silicate derivatives compared with lithium disilicate ceramic when used as ultra-thin occlusal veneers on eroded molars. The null hypothesis stated that there would be no significant differences in load-bearing capacity (F_max). Material and Methods: Four groups were tested: three groups with lithium silicate derivatives—“Celt” (Celtra, Dentsply Sirona, Bensheim, Germany), “Vita” (Vita Suprinity PC, Vita Zahnfabrik, Bad Säckingen, Germany), and “Nice” (n!ce, Straumann, Basel, Switzerland)—and a control group with lithium disilicate ceramic, “Emax” (IPS e.max CAD, Ivoclar Vivadent) (n = 20 per group). Extracted molars (n = 80) were prepared to simulate erosion and restored with occlusal veneers designed and milled by using CAD/CAM technology. After thermo-mechanical aging, the specimens were subjected to static load testing until fracture. Failure types were recorded and analyzed. Statistical evaluation included the Wilcoxon rank-sum test for group comparisons and Weibull distribution modeling to assess fracture probabilities. Results: Thermo-mechanical aging caused restoration debonding in three specimens from the “Nice” and “Celt” groups, resulting in fatigue resistance of 100% for “Emax” and “Vita”, 90% for “Celt”, and 95% for “Nice”. The mean F_max values ranged from 892 N to 2087 N, with the “Vita” group demonstrating the highest values. Significant differences in stress values were observed among groups (p < 0.05). Cohesive failure was the most frequent failure mode. Conclusions: All tested lithium silicate derivatives demonstrated high load-bearing capacity and are suitable for ultra-thin occlusal veneers on eroded molars. Cohesive failures dominated, indicating reliable material performance and stable bonding under load. Full article

Background: Technological progress in the field of prosthetic dentistry has changed the workflow, optimizing times and increasing the possible choices of prosthetic rehabilitation. Methods: The adaptability of three resin plates to the plaster model was evaluated by visual evaluation and by filling out a questionnaire in which two areas present in three silicone impressions obtained with three different construction methods were selected, including the traditional method, CAD/CAM method for milling, and CAD/CAM method for addition. Results: The results showed that although silicone 3 obtained with the additive method had better performances in the selected areas, the p-value of 0.735 was >0.05, and therefore there are no statistically significant differences between the different silicone impressions. Furthermore, a poor agreement between the evaluators was found (k 0.184). Conclusions: This work conducted in vitro highlights an important aspect of the choice of material used for impressions in cases of prosthetic relining. More in-depth studies with larger samples and objective measurement methods will be needed to compare fit data across different prosthetic construction modalities. Full article

Background: Resin-bonded fixed dental prostheses (RBFDPs) have become an increasingly popular minimally invasive solution for replacing missing anterior teeth. However, their long-term success is influenced by factors such as bridge design and material selection. Methods: This systematic review and meta-analysis aimed to assess the impact of different bridge designs on the clinical performance and failure risks of anterior ceramic RBFDPs. A comprehensive search of electronic databases was conducted to identify clinical studies published in English up to January 2025. Nine studies, including randomized controlled trials, cohort studies, and clinical trials, met the inclusion criteria. Results: The analysis revealed that single-retainer RBFDPs demonstrated lower failure rates than two-retainer models (RR: 0.36, 95% CI: 0.17–0.75). Among failure types, fractures were significantly less common in cantilever designs compared to two-retainer designs (RR: 0.25, 95% CI: 0.09–0.73), while no significant differences were observed in debonding rates (OR: 0.40, 95% CI: 0.015–1.10). Conclusions: In terms of material selection, all-ceramic RBFDPs in cantilever designs exhibited significantly lower failure rates (RR: 0.12, 95% CI: 0.03–0.43), whereas metal-ceramic RBFDPs showed no significant difference in failure rates based on bridge design (RR: 0.56, 95% CI: 0.21–1.53). These findings suggest that all-ceramic cantilever RBFDPs may offer superior long-term outcomes, highlighting the importance of precise preparation and cementation protocols for clinical success. Full article

Background: Assessment of functional occlusion is crucial in orthodontics and prosthodontics. With scientific advancements, optical jaw tracking systems are increasingly used to evaluate mandibular kinematics. Objectives: To compare the performance of an optical jaw tracking system (Modjaw^®) and a traditional condylar position indicator (CPI) in identifying condylar position discrepancies within an orthodontic population. A secondary objective was to explore the association between condylar discrepancies and temporomandibular disorders (TMD). Methods: Measurements were collected from 132 patients consecutively recruited from the private practice of a coauthor, using Modjaw and CPI, analyzing discrepancies in the sagittal, vertical, and transverse planes. TMD presence was determined clinically and using the DC-TMD questionnaire. Receiver operating characteristic (ROC) curves and diagnostic metrics were used to evaluate the tools’ performance. Results: No correlation was found between CPI and Modjaw measurements. CPI did not effectively discriminate between patients with and without TMD, with areas under the curve (AUC) not statistically significant. In contrast, the AUCs for Modjaw were 0.683 for the vertical plane (p = 0.001), 0.654 for the sagittal plane (p = 0.004), and 0.777 for the transverse plane (p < 0.001). The cut-off values for TMD screening using Modjaw were established at 2 mm (vertical), 1 mm (sagittal), and 0.5 mm (transverse), exhibiting some specificity, especially in the transverse dimension, but very low sensitivity. Conclusions: No correlation was found between Modjaw and CPI for assessing condylar position discrepancies. While these discrepancies may aid orthodontic treatment planning, they lack sufficient sensitivity for reliable TMD diagnosis. Modjaw’s cut-off points may help exclude TMD risk in orthodontic patients. Full article

Introduction: Additive manufacturing has emerged as a promising solution for improving the accessibility and affordability of upper limb prostheses. Despite the growing need, traditional prosthetic devices remain costly and often inaccessible, particularly in underserved regions. This review examines the current landscape of 3D-printed upper limb prostheses, focusing on their design, functionality, and cost-effectiveness. It aims to assess the potential of 3D-printing upper limb prostheses in addressing current accessibility barriers. Methods: A two-phase approach was used to analyze the literature on 3D-printed upper limb prostheses. The first phase involved a literature search using keywords related to 3D printing and upper limbs prostheses. The second phase included data collection from online platforms such as Enabling the Future, Thingiverse, and NIH 3D Print Exchange. Studies focusing on the design, fabrication, and clinical application of 3D-printed prostheses were included. The results were organized into categories based on design characteristics, kinematic features, and manufacturing specifications. Results: A total of 35 3D-printed upper limb prostheses were reviewed, with the majority being hand prostheses. Devices were categorized based on their range of motion, actuation mechanism, materials, cost, and assembly complexity. The e-NABLE open-source platform has played a significant role in the development and dissemination of these devices. Prostheses were classified into cost categories (low, moderate, and high), with 64% of models costing under USD 50. Most designs were rated as easy to moderate in terms of assembly, making them accessible for non-specialist users. Conclusions: Three-dimensional printing offers an effective, low-cost alternative to traditional prosthetic manufacturing. However, variability in design, a lack of standardized manufacturing protocols, and limited clinical validation remain challenges. Future efforts should focus on establishing standardized guidelines, improving design consistency, and validating the clinical effectiveness of 3D-printed prostheses to ensure their long-term viability as functional alternatives to traditional devices. Full article

Objectives: The term ‘prosthesis’ in reference to breast implants is used to clarify its distinction from the general term ‘breast implant’, which is widely adopted by plastic surgeons. This terminology highlights the role of the implant as a functional tissue substitute, particularly in post-mastectomy reconstruction, rather than solely as a cosmetic enhancement. This distinction is relevant for understanding the long-term implications of implant-based reconstruction and the associated complications. The aim of this systematic review was to compile and analyze the current evidence on the long-term complications associated with breast implants. We explored how these complications vary depending on implant type, surgical techniques, patient-specific factors, and the indication for implantation (cosmetic vs. reconstructive). These indications were analyzed separately to avoid assumptions regarding their correlation with surgical techniques. Methods: A systematic search was conducted across PubMed, Web of Science, and Scopus for studies published up to December 2024, following PRISMA 2020 guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. An initial search identified 1480 studies. After screening and applying inclusion criteria, 11 studies were selected for the final analysis. Studies included in this review reported long-term complications in human subjects, were published in English, and evaluated breast implants. The quality of the included studies was assessed using the ROBINS-E tool. Additionally, subgroup analyses examined differences based on implant type (silicone vs. saline), surgical techniques, and patient characteristics, such as age, comorbidities, and the duration of follow-up. Results: This review study was performed between September 2024 and December 2024. A total of 11 studies were included in the review. The included studies were published between 1997 and 2021, providing a long-term perspective on breast implant complications. The most frequently reported complications were capsular contracture, implant rupture, seroma, and infection, with capsular contracture being the most prevalent. Silicone implants were associated with a higher risk of rupture compared to saline implants. Techniques using textured implants and dual-plane placements were found to reduce the incidence of capsular contracture. Patient-related factors, such as age and smoking status, were identified as significant risk factors for complications, while longer follow-up periods revealed more late-onset complications. Conclusions: This review underscores the importance of understanding the long-term risks of breast implants and highlights the need for personalized surgical planning and thorough follow-up care. Future studies should focus on standardizing outcomes reporting and further evaluating the safety and effectiveness of new implant materials and surgical approaches. Full article

Background: Digital impression techniques for edentulous patients present unique challenges due to the absence of stable anatomical landmarks and variable soft tissue morphology. While intraoral scanners have shown promising results in dentate patients, their application in edentulous cases remains problematic, with reported accuracy deviations ranging from 60.6 ± 11.9 μm to 67.2 ± 6.9 μm compared to conventional methods. Material and Methods: This pilot study employed a within-subject, repeated-measures design comparing four scanning protocols in a fully edentulous patient (age: 42, BMI: 24.3 kg/m², Cawood and Howell Class III). Digital scans were performed using iTero Element 5D and Trios 5 scanners (n = 10 scans per group), with and without a modified technique incorporating standardized reference points (1 mm diameter, 5 mm intervals) and systematic soft tissue management. A conventional impression-derived digital model served as the reference standard. Accuracy assessment utilized best-fit alignment and root mean square (RMS) calculations through Geomagic Control X software (version 2020.1.1). Results: The modified technique demonstrated significantly improved accuracy (Groups C/D: 57.8–59.7 μm) compared to standard protocols (Groups A/B: 66.9–68.2 μm) (p < 0.001). Mean scanning times were reduced by 37% with the modified technique (2:10 ± 0:09 min vs. 3:24 ± 0:15 min). Inter-operator reliability showed excellent agreement (ICC = 0.92, 95% CI: 0.88–0.95). Soft tissue management significantly improved vestibular area accuracy (48.7 ± 6.3 μm vs. 72.4 ± 8.9 μm, p < 0.001). Conclusions: The proposed scanning strategy incorporating reference points and systematic soft tissue management significantly improved both accuracy and efficiency in digital impressions of edentulous arches. The technique showed excellent reproducibility and potential clinical applicability across different scanner systems. These findings warrant validation through larger-scale clinical trials to establish definitive protocols for digital impression-taking in edentulous patients. Full article

Background/Objectives: Digital workflows for implant-supported full-arch restorations remain challenging. This study evaluated the accuracy and precision of digital impressions using reverse scan body (RSB) prototypes and intraoral scanners (IOSs) for rehabilitating fully edentulous patients following the All-on-4 protocol. Secondary objectives included comparing accuracy between expert clinicians and beginners, as well as desktop scanners and various RSB designs. Methods: An in vitro study was conducted using a fully edentulous mandible model with four Osstem TSIII implants. A final-year dental student and an expert clinician captured digital impressions using IOSs and desktop scanners. Four groups were analyzed: (A) original scan bodies with the IOS, (B) short RSBs with the IOS, (C) RSBs with desktop scanners (short sandblasted, long sandblasted, long coated), and (D) a control group using original scan bodies with a desktop scanner. Root mean square (RMS) values measured dimensional differences, with statistical analysis performed using the Wilcoxon signed-rank test and one-way ANOVA (α = 0.05). Results: A total of 42 scans were analyzed. No significant difference was found between expert and student for original scan bodies using the IOS (p = 0.220), while RSB prototypes showed significant differences (p = 0.008). No significant accuracy differences were noted between original scan bodies and RSBs with the IOS, but IOSs outperformed desktop scanners. Among RSBs scanned with desktop scanners, no significant differences were observed between designs. Conclusions: RSB prototypes are a viable alternative to original scan bodies for fully digital workflows in All-on-4 rehabilitations, with IOSs offering superior accuracy. However, proper training is crucial for optimizing RSB accuracy. Variations in height and coating did not impact overall accuracy. Full article

Background/Objectives: With advancements in technology, three-dimensional (3D) printing has become widely used, offering many advantages. Recently, 3D printing has been utilized for the fabrication of permanent crowns. However, there is still a need for more information regarding the technology, materials, and factors that may affect the properties of 3D-printed permanent crowns. Methods: This review was conducted to collect and assess information regarding the performance of 3D printing technology for permanent crown fabrication. An electronic search was performed using various search engines (Scopus, PubMed, Google Scholar) up to December 2024, yielding 123 articles. After screening, 24 articles that specifically investigated 3D-printed crowns were included. Results: Based on the findings, two categories of materials for 3D-printed permanent crowns were identified: ceramic-based and resin-based. Among the technologies used, digital light processing (DLP) was the most common, reported in 11 studies, followed by stereolithography (SLA) in 7 studies, and lithography-based ceramic manufacturing (LCM) in 4 studies. Conclusions: Ceramic-based crowns demonstrated higher performance compared to resin-based crowns. However, resin-based crowns were found to be clinically acceptable. Ceramic-based crowns are recommended for permanent crown fabrication, while resin-based crowns require further investigation to address the limitations of the materials and technologies used. Full article