Research Appraisals
Evidence-based critical appraisals of the latest medical research, systematically evaluated using Oxford CEBM methodology.
Showing 7 appraisals
BMC oral health
Accuracy of virtual facebow compared to conventional facebow: a systematic review
BACKGROUND: Digital technologies are rapidly evolving and have been introduced across many fields in dentistry, particularly prosthetic and restorative dentistry. In digital treatment planning, virtual articulators are helpful in simulating complex maxillomandibular movements and analyzing occlusion. Despite these advancements, evidence-based literature standardizing the transfer of clinical data to virtual environments remains limited. The aim of this review was to explore the accuracy of various methods in transferring maxillary digital models to virtual articulators compared with conventional facebow techniques. METHODS: The research (PICO) question focused on assessing the accuracy of virtual facebow transfer compared to that of conventional facebows. An electronic search was performed in 3 databases between January 2014 to December 2025: PubMed/MEDLINE, Scopus, and Web of Science. Eligibility criteria included in vitro studies, clinical trials, case reports, clinical reports, and clinical techniques that evaluated the accuracy of virtual articulation in fixed prosthodontics for dentate patients, published in English. Studies were excluded if they were not in English, involved orthognathic surgery, focused on edentulous patients, or were published before 2014. A comprehensive search was conducted in December 2025. Two reviewers (PE, HA) independently examined the identified papers in accordance with the predetermined qualifying criteria. For each included study, publication details, study characteristics, and methodological aspects were documented. RESULTS: The total number of articles retrieved was 1,916. Of these articles, 10 met the inclusion criteria and were used for qualitative synthesis. Several techniques were reported for transferring the maxillary model to virtual articulator, such as digital photographs, face scans with or without intraoral or extraoral scan body, smartphone applications, digital photographs using Kois glasses, CBCT, and stereophotogrammetry. Most studies showed comparable accuracy of different digital methods that transfer the maxillary cast to the articulator. However, one study showed that the photography-based method demonstrated superior trueness and precision compared to both facial scanning and the conventional facebow technique. Another study found that the accuracy of positioning a maxillary digital scan relative to a 3D facial scan using a virtual facebow technique is highly dependent on the facial scanning method employed. CONCLUSIONS: Virtual facebow transfer can be recorded using techniques such as digital photographs, face scans, virtual facebow software, and smartphone scanning. Virtual facebow systems demonstrate promising repeatability and clinically acceptable transfer accuracy in selected workflows; however, due to heterogeneity among available studies, definitive conclusions regarding any improvement over conventional techniques cannot yet be drawn. Further standardized in vitro and clinical studies with large sample sizes, standardized assessments, and comparison methods are needed to draw meaningful conclusions in order to prove precedence of one method over the other. However, the use of a device to facilitate the transfer of a virtual maxillary cast to a virtual articulator has been promising.
13 July 2026
Read appraisal →The International journal of oral & maxillofacial implants
The Effect of Sinus Elevation and Onlay Grafts on Biologic and Technical Complications of Implants Placed in the Resorbed Posterior Maxilla: A Systematic Review and Analysis of Studies
PURPOSE: To evaluate whether biologic and technical complications differ when sinus elevation is used alone versus when used in combination with onlay grafting prior to implant placement in the severely resorbed posterior maxilla, with particular emphasis on the impact of crown-to-implant ratios (CIRs) on clinical outcomes. MATERIALS AND METHODS: An electronic search from January 2000 to December 2023 was performed in four databases following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines with a focused Population/Problem, Intervention, Comparison, and Outcome (PICO) question. The quality of the reports was established using a modified Cochrane Collaboration tool. RESULTS: Out of 1,199 studies, 20 articles were selected, including 16 articles on sinus augmentation (SA) and 4 articles on both SA and onlay grafts (SAOG). The studies involved 1,245 patients, with 81.8% of patients receiving SA and 18.1% receiving SAOG. Implant survival rates ranged from 80.25% to 100%, with an overall success rate of 91.5% to 100%. Complications included biologic issues (eg, membrane perforation) and mechanical issues (eg, graft loss). The average follow-up period was 60 months. CONCLUSIONS: Limited evidence exists on implant outcomes following SA versus onlay grafting in the atrophied maxilla. Further randomized controlled trials are needed to compare these techniques, emphasizing prosthetically driven augmentation for optimal implant positioning.
14 June 2026
Read appraisal →The International journal of oral & maxillofacial implants
Comparison Between Computer-Assisted and Freehand Dental Implant Placement: A Systematic Review and Meta-analysis
PURPOSE: To compare computer-assisted implant surgery (CAIS) and freehand implant placement (FHIP) in terms of clinical and radiographic outcomes. MATERIALS AND METHODS: This systematic review and meta-analysis included a comprehensive search of five databases (PubMed, Embase, CINAHL, Scopus, and Web of Science), along with handsearching and cross-referencing, which identified randomized controlled trials (RCTs) comparing CAIS and FHIP literature published up to November 2024. Outcomes included marginal bone loss (MBL), implant survival rate, patient satisfaction, pink esthetic scores, probing depth, and complications. The Cochrane risk of bias (RoB) tool and the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach were used to assess study quality and evidence certainty. Meta-analysis and sensitivity/subgroup analyses were also conducted. RESULTS: A total of 12 publications from 9 RCTs (395 participants, 1,242 implants) were included. Although overall differences in MBL and implant survival were not statistically significant, subgroup analyses revealed several significant findings. CAIS demonstrated significantly reduced MBL in fresh socket placements (P = .04), higher patient satisfaction (P = .03), and improved pink esthetic scores (P = .009). FHIP was associated with fewer biologic complications (P = .04) and lower MBL values when compared to tissuesupported CAIS (P = .03). Sensitivity analyses confirmed robustness for most outcomes; however, evidence quality ranged from very low to moderate, and six studies showed a high RoB. CONCLUSIONS: Considering the limitations related to the quality of the included studies, both CAIS and FHIP achieved high survival rates (> 98%). CAIS showed advantages in fresh socket cases and esthetic/patient-reported outcomes, while FHIP had fewer biologic complications and better outcomes when using an open-flap approach.
13 June 2026
Read appraisal →The International journal of prosthodontics
A Systematic Review and Meta-analysis Evaluating the Survival, Failure, and Complication Rates of Metal-Ceramic, Veneered, and Monolithic All-Ceramic Tooth-Supported Single Crowns-Part 1
PURPOSE: To evaluate five-year survival rates of metal-ceramic, veneered all-ceramic, and monolithic all-ceramic tooth-supported single crowns (SCs) and assess biological and technical complications. MATERIALS AND METHODS: A systematic search of Medline (PubMed), Embase, and CENTRAL (2014-2024) identified clinical studies on tooth-supported fixed dental prostheses (≥3 years mean follow-up). Manual screening and 30 studies from previous reviews were added. Sixty-four studies met inclusion, reporting on 3,509 metal-ceramic and 8,051 all-ceramic SCs. Robust Poisson regression models were used to estimate pooled five-year survival rates. RESULTS: Twelve studies investigated metal-ceramic crowns, 49 all-ceramic crowns, and three both. Five-year survival rates were: 98.5% for monolithic lithium-disilicate reinforced glass-ceramic, 97.3% for veneered densely-sintered zirconia, 97.1% for metal-ceramic, 96.8% for monolithic densely-sintered zirconia, 95.7% for veneered leucite/lithium-disilicate reinforced glass-ceramic, 94.5% for densely-sintered alumina, 94.3% for glass-infiltrated alumina, 90.4% for feldspathic/silica-based ceramic. Survival rates of feldspathic/silica-based ceramic (P<0.0001), glass-infiltrated alumina (P=0.019), densely sintered alumina (P=0.002), and veneered leucite/lithium-disilicate reinforced glass-ceramic (P=0.021) were significantly lower than monolithic lithium-disilicate SCs. Except for feldspathic/silica-based ceramic and metal-ceramic crowns, material/design types performed similarly in anterior and posterior regions. Monolithic lithium-disilicate and monolithic zirconia crowns showed significantly fewer ceramic fractures and chipping compared to veneered alternatives. CONCLUSIONS: Lithium-disilicate and zirconia-based all-ceramic SCs achieve five-year survival rates comparable to metal-ceramic crowns. Monolithic designs reduce fracture and chipping risk, improving long-term clinical outcomes.
28 May 2026
Read appraisal →Journal of prosthodontic research
Flexural strength of translucent zirconia for single crowns and fixed dental prostheses-A systematic review
PURPOSE: The aim of this systematic review was to analyze the reported flexural strength values of commercially available translucent zirconia materials. Additionally, data were evaluated to assess the impact of different specimen preparations and test methods. STUDY SELECTION: This systematic review was conducted according to the PRISMA guidelines. Electronic searches were performed to identify in vitro studies published between January 1, 2013, and March 15, 2025, that reported flexural strength values of translucent zirconia and included the names of the tested materials and manufacturers. Flexural strength values were analyzed to assess the effects of yttria content, specimen processing, surface treatments, and test methods using Kruskal-Wallis analysis of variance (α = 0.05) and forest plots. RESULTS: A total of 78 laboratory studies met the inclusion criteria. The overall flexural strength values were significantly higher for 4Y-PSZ (803± 233 MPa) than for 5Y-PSZ materials (570 ± 116 MPa) (P = 0.005). Specimen processing, surface treatments, and test methods significantly affected the flexural strength values for 5Y-PSZ (P < 0.001) but not for 4Y-PSZ (P > 0.05). CONCLUSIONS: This systematic review highlights the challenges in comparing the flexural strength values of translucent zirconia owing to differences in processing parameters. Further standardization of test methods and adherence to ISO 6872 would improve comparability. Our findings support the clinical use of 4Y-PSZ for three-unit fixed dental prostheses (FDPs) and 5Y-PSZ for three-unit FDPs in the anterior region based on ISO 6872.
13 Apr 2026
Read appraisal →Journal of prosthodontic research
Clinical performance, accuracy, and physical-mechanical properties of 3D-printed removable partial denture metal frameworks compared with conventionally and partially digitally produced frameworks: A systematic review.
PURPOSE: This systematic review evaluated the clinical performance, physical-mechanical properties, and accuracy of removable partial denture (RPD) frameworks fabricated using three-dimensional (3D) printing technologies-specifically, selective laser sintering (SLS), selective laser melting (SLM), and direct metal laser sintering (DMLS)-compared to those produced by conventional casting or methods using a partial digital workflow. STUDY SELECTION: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines, a literature search was conducted in the PubMed, Scopus, Web of Science, and Cochrane databases in October 2024. Studies were included if they compared the fit, accuracy, mechanical and physical properties, and clinical outcomes of metal RPD frameworks made using 3D printing technologies with those produced using conventional casting or partial digital methods. The risk of bias was assessed using appropriate tools (modified CONSORT, ROB2, and ROBINS-I) based on the study design and a qualitative analysis was conducted. This study received no funding and was registered with PROSPERO (#CRD42024597225). RESULTS: Thirty studies were included: 12 compared 3D printing technologies with conventional casting, eight with partial digital methods, and 10 with both. Clinically, 3D-printed frameworks could improve retention and patient satisfaction. The laboratory results showed higher density, better mechanical properties (yield strength, surface roughness, and microhardness), and varied accuracy by component and method, with SLM and DMLS often outperforming conventional casting. The evidence was limited by methodological variability, a moderate risk of bias in many studies, and inconsistencies across the study designs and parameters. CONCLUSIONS: 3D-printed RPD metal frameworks demonstrated clinical accuracy and mechanical-physical performance comparable or superior to those of conventional and partially digital methods for RPD frameworks, with ongoing advances expected to further enhance their precision and clinical applicability.
13 Apr 2026
Read appraisal →Journal of prosthodontic research
The clinical performance of CAD/CAM-fabricated hybrid ceramic restorations in cases with severe wear: A 3-year clinical trial
PURPOSE: To evaluate the clinical use of CAD/CAM hybrid ceramics in patients with severe tooth wear. METHODS: Forty-nine patients with severe tooth wear underwent prosthetic management with 116 hybrid ceramic restorations. The restorations were evaluated at 1 week and at 3, 6, 12, 18, 24, 30, and 36 months after placement. The amount of wear on the restorations, antagonist teeth, and opposite teeth was compared using digital superimposition analysis. A questionnaire was used to evaluate participants' satisfaction with the restorations. Complications were recorded, and survival rates were estimated using Kaplan-Meier analysis. RESULTS: The clinical performance of the restorations was stable for esthetic, functional, and biological parameters up to 3 years, except for greater changes in "surface and margin staining" and "fracture and retention." There was no significant difference in the amount of progressive wear among the restorations, antagonist teeth, and opposite side teeth until 18 months; however, the wear on the restorations increased gradually up to 36 months. Higher scores and identical satisfaction results were obtained for the chewing efficiency and cleanability during the observation period. The most common complications were restoration dislodgement (5.2%) and partial marginal chipping (4.3%), which were clinically repaired. Four restorations (3.4%) were extensively fractured and replaced. The estimated survival rate of the hybrid ceramic restorations at 3 years was 88.0%. CONCLUSIONS: The clinical use of hybrid ceramic restorations in patients with severe tooth wear improved chewing efficiency and esthetics, provided adequate resistance for load-bearing, and delivered a stable treatment outcome after functional use.
13 Apr 2026
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