Journal of Prosthetic Dentistry最新文献

{"title":"Mechanical behavior of subtractively and additively manufactured zirconia and polyetheretherketone implant abutments after thermomechanical aging.","authors":"Oguzhan Sari, Rüştü Ersoy Sakarya, Mustafa Gundogdu","doi":"10.1016/j.prosdent.2025.05.005","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.05.005","url":null,"abstract":"<p><strong>Statement of problem: </strong>Zirconia and polyetheretherketone (PEEK) implant abutments, manufactured using both subtractive and additive methods, have been introduced. Although the restorative materials could play an important role in the mechanical behavior of implant-supported prostheses, relevant in vitro studies are lacking.</p><p><strong>Purpose: </strong>The purpose of this in vitro study was to compare the fracture resistance and failure mode of the 1-piece custom titanium abutment and 2-piece custom zirconia and PEEK abutments (with a titanium base) according to the manufacturing techniques (subtractive and additive).</p><p><strong>Material and methods: </strong>A maxillary central incisor was simulated for this study. A total of 50 custom abutments were prepared using 3 different abutment materials (titanium, zirconia, and PEEK) and 2 different manufacturing techniques (subtractive and additive) divided into 5 different groups: Group C; control group, premilled titanium abutment, Group SZ; subtractively manufactured zirconia, Group AZ; additively manufactured zirconia, Group SP; subtractively manufactured PEEK, and Group AP; additively manufactured PEEK. Adhesive resin cement was used to cement the custom abutment to the ti-base and cobalt chromium crown to the custom abutment. The specimens were exposed to thermomechanical aging according to the ISO standard 14801. A static force was then applied with a crosshead speed of 1 mm/minute. Failure mode of the specimens was recorded. The fracture resistance values were analyzed with the Kruskal Wallis test, and multiple comparisons were made with the Dunn test (α=.05).</p><p><strong>Results: </strong>The following average fracture resistance values were found (fracture load [N]/bending moment [Ncm]): Group C (711/523), group SP (504/381), group SZ (460/347), group AZ (362/273), and group AP (199/150). The fracture resistance values of the C group were significantly higher than those of the AZ and AP groups (P<.05) and those of the AP group were significantly lower than those of the SP and SZ groups (P<.05). Screw fracture was the predominant cause of failure in all test groups except the AP group, in which abutment fracture without complete separation was observed.</p><p><strong>Conclusions: </strong>The C group was the most mechanically durable. The SZ, SP, and AZ custom abutments had the potential to withstand the physiological occlusal forces that occur in the anterior region, whereas that of AP did not meet the occlusal forces.</p>","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144182103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of marginal and internal fit of 10-unit fixed dental prostheses fabricated from cobalt chromium alloys or zirconia ceramics using digital workflows.","authors":"Vera Malina Hupe, Florian Beuer, Guido Sterzenbach, Ufuk Adali","doi":"10.1016/j.prosdent.2025.05.008","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.05.008","url":null,"abstract":"<p><strong>Statement of problem: </strong>Long-span fixed dental prostheses (FDPs) can be challenging to fabricate with adequate marginal and internal fit. The performance of restorations fabricated from cobalt chromium or zirconia using a completely digital workflow requires further evaluation to ensure clinical acceptability.</p><p><strong>Purpose: </strong>The purpose of this in vitro study was to evaluate and compare the marginal and internal fit of 10-unit FDPs fabricated from cobalt chromium or zirconia by using digital scanning and computer-aided design and computer-aided manufacturing (CAD-CAM).</p><p><strong>Material and methods: </strong>Twenty-four complete arch digital scans of a typodont model with 6 prepared teeth were acquired to design and mill 12 cobalt chromium and 12 zirconia 10-unit FDP frameworks. For each framework, measurements from all 6 abutments and from both buccolingual and mesiodistal sections were pooled, yielding 1 mean value per measurement area per specimen. Marginal, chamfer, internal, and overall cement gaps were evaluated with the silicone replica technique. Trueness was defined as the difference between the measured gap and the preset cement spacer. Data were analyzed with 2-sample t tests on the pooled specimen means (α=.05).</p><p><strong>Results: </strong>Mean gap measurements for cobalt chromium versus zirconia were (gap value ±standard deviation) as follows: marginal, 68.7 ±14.6 µm versus 53.3 ±11.8 µm; chamfer, 66.8 ±10.6 µm versus 58.1 ±10.8 µm; internal, 77.7 ±6.5 µm versus 95.8 ±9.4 µm; and overall cement gap, 74.2 ±8.2 µm versus 81.3 ±9.7 µm. The zirconia restorations exhibited a significantly smaller marginal gap (P=.01), whereas the cobalt chromium frameworks showed a significantly smaller internal gap (P<.001), with the chamfer gap being statistically similar (P=.061). Zirconia demonstrated significantly higher trueness in the marginal area (P=.01), while the internal gap trueness did not differ significantly between the 2 materials (difference 1.9 µm, P=.56). Both materials remained below the 120 µm clinical threshold for acceptable fit.</p><p><strong>Conclusions: </strong>A digital workflow yielded precise, clinically acceptable fit for 10-unit restorations fabricated from both cobalt chromium and zirconia. Zirconia demonstrated significantly higher marginal trueness, whereas the internal gap trueness did not differ significantly between the 2 materials. Optimizing cement spacer settings and evaluating deviations from the planned spacer are crucial for an accurate assessment of fit.</p>","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144159695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Factors leading to implant failure: An umbrella review of meta-analyses of observational studies and trials.","authors":"Koay Chun Giok, Sajesh K Veettil, Chen-Xuan Wei, Rohit Kunnath Menon","doi":"10.1016/j.prosdent.2025.04.041","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.04.041","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Statement of problem: &lt;/strong&gt;The evidence concerning factors leading to implant failure remains inconclusive. Existing systematic reviews have reported mixed results for patient-related, surgical, and prosthetic factors contributing to implant failure.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Purpose: &lt;/strong&gt;The purpose of this umbrella review was to summarize the evidence and assess existing biases from meta-analyses of randomized controlled trials (RCTs) and observational (cohort and case-control) studies to establish clinically relevant factors associated with implant failure.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Material and methods: &lt;/strong&gt;The study had been registered with the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42025634487). The Scopus, PubMed, the Cochrane Database of Systematic Reviews, and Epistemonikos databases were searched from inception until June 2024, and the effect sizes were recalculated using a random-effects model for each meta-analysis. Between-study heterogeneity, 95% prediction interval, small-study effects, excess significance, and credibility ceilings were evaluated. The credibility of evidence from meta-analyses of cohort and case-control studies was ranked by established criteria as nonsignificant, weak, suggestive, highly suggestive, or convincing.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;A total of 2922 publications were identified, 224 full-texts were evaluated, and 25 articles describing 35 associations were included in the study. Among meta-analyses of RCTs (n=9), 6 (67%) statistically significant associations were identified (P&lt;.05). According to the GRADE assessment, turned versus anodized implants, submerged versus nonsubmerged implant healing, and bone augmentation with long implants versus short implants were associated with a higher risk of implant failure (high certainty evidence). Short implants (&lt;10 mm) versus long implants (&gt;10 mm) and immediate versus delayed implant placement were associated with higher risk for implant failure (moderate certainty evidence). Among the meta-analyses of cohort and case-control studies (n=26), 18 (69%) associations were statistically significant (P&lt;.05). None were graded as convincing. Highly suggestive evidence was established for the association between smoking and implant failure. Suggestive evidence emerged for associations including periodontally compromised versus periodontally healthy patients, proton pump inhibitor therapy, Crohn's disease, bone quality type II versus type IV, bone quality type III versus type IV, nonsubmerged immediately loaded versus submerged delayed loaded implants, short implants (&lt;10 mm) versus long implants (&gt;10 mm), selective serotonin re-uptake inhibitor therapy, turned versus anodized implants, and immediately loaded versus conventionally loaded implants. These findings remained robust after sensitivity analyses.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;Observational studies suggest that smoking is associated with an increased incidence of implant ","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144159698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation of anthropometric methods with standard method of recording the vertical dimension of occlusion: A systematic review and meta-analysis.","authors":"Naman Goyal, Pragati Kaurani, Ayushi Goyal, Shweta Mangal, Vineetha Karuveettil, Georg Gutjahr, Chandrashekar Janakiram","doi":"10.1016/j.prosdent.2025.04.029","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.04.029","url":null,"abstract":"<p><strong>Statement of problem: </strong>Numerous anthropometric methods have been researched regarding their correlation with the standard method of recording vertical dimension of occlusion. Among these, the most closely correlated method is unknown.</p><p><strong>Purpose: </strong>The purpose of this systematic review and meta-analysis was to analyze different anthropometric methods with the conventional method of recording vertical dimension of occlusion and to suggest an anthropometric method closely correlated with the standard method.</p><p><strong>Material and methods: </strong>An electronic systematic search was conducted in PubMed, Scopus, Embase and in other sources using a formulated search strategy. Articles were screened using inclusion criteria with population: edentulous or dentulous individuals (having 28 fully erupted periodontally sound natural teeth) with Angle Class I occlusion; intervention: anthropometric methods of recording vertical dimension; comparison: standard method of recording vertical dimension; outcome: correlation of vertical dimension determined by anthropometric method and standard method; and study type: cross-sectional observational studies. Meta-analysis was performed to correlate different anthropometric measurements with vertical dimension of occlusion. The data were pooled using both the common effects and random effects model, and heterogeneity was determined using the I² test. Subgroup analysis was performed to estimate correlation based on sex. Risk of bias assessment was done using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool.</p><p><strong>Results: </strong>Thirteen cross-sectional observational studies with a total of 3275 participants (1618 men and 1657 women) and using 11 different anthropometric methods were included. Overall, the thumb length showed the strongest correlation (common effects: 0.63, random effects: 0.57, heterogeneity: 99%). In men, the distance between the distal outer canthus and rima oris (common effects: 0.57, random effects: 0.58, heterogeneity: 86%) and, in women, the little finger length (common effects: 0.46, random effects: 0.46, heterogeneity: 94%) showed the strongest correlation. High risk was observed in domains related to patient selection and the index test in most studies.</p><p><strong>Conclusions: </strong>Overall, the anthropometric methods showed a high correlation with the standard method of recording anthropometric methods and can be used as a method of recording the vertical dimension of occlusion. The thumb length showed the strongest correlation, making it potentially the most accurate predictor of vertical dimension of occlusion. However, overall high heterogeneity was observed across studies.</p>","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144132586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of print orientation on sorption, solubility, and monomer elution of 3D printed resin restorative materials.","authors":"Shaymaa Mudhaffer, Nick Silikas, Julian Satterthwaite","doi":"10.1016/j.prosdent.2025.04.040","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.04.040","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Statement of problem: &lt;/strong&gt;The long-term stability and clinical safety of 3 dimensional (3D) printed dental restorative resins in the oral cavity remains uncertain, despite their increased use.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Purpose: &lt;/strong&gt;The purpose of this in vitro study was to evaluate the impact of different printing orientations on the sorption, solubility, and monomer elution of various 3D printed definitive and interim dental restorative resins compared with that of milled resin materials.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Material and methods: &lt;/strong&gt;Two 3D printed materials for definitive restoration, VarseoSmile Crownplus (VCP) and Crowntec (CT) and 3 for interim restorations, C&B MFH (ND), Dima C&B temp (DT), and GC temp print (GC), were additively manufactured in 3 orientations (0, 45, and 90 degrees). A digital light processing (DLP) 3D printer (ASIGA MAX UV) was used with postprocessing parameters as per the manufacturers' recommendations. Specimens for sorption and solubility (14×14×1 mm) were stored in artificial saliva at 37 °C and measured over a 90-day period (n=6). Specimens used for monomer elution (14×14×2 mm) were stored in a 75% ethanol and water (E/W) solution, and elution was assessed after 1 and 7 days using ultra-high performance liquid chromatography coupled with mass spectrometry (UHPLC/MS) (n=4). Milled materials, Lava Ultimate (LU) and Telio CAD (TC), were used as controls. Multiple way ANOVA, 1-way ANOVA, and Tukey HSD post hoc tests (α=.05) were used to analyze the data.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Printing orientation significantly influenced the sorption and solubility of 3D printed resins (P=.008) but did not influence their monomer elution (P=.774). All materials met the recommended International Organization for Standardization (ISO) 4049 standards for sorption and solubility, except ND, which exceeded the maximum recommended sorption value (57.1 μg/mm&lt;sup&gt;3&lt;/sup&gt;). The 3D printed interim materials ND, DT, and GC exhibited greater sorption (27.3-57.1 μg/mm&lt;sup&gt;3&lt;/sup&gt;), solubility (2.6-3.6 μg/mm&lt;sup&gt;3&lt;/sup&gt;), and monomer elution (53.2-87.4 μmol/L) compared with the definitive materials VCP (9.8-0.9 μg/mm&lt;sup&gt;3&lt;/sup&gt;, 50.5 μmol/L) and CT (9.4-0.02 μg/mm&lt;sup&gt;3&lt;/sup&gt;, 51.3 μmol/L). All 3D printed resins exhibited lower sorption (9.4-30.1 μg/mm&lt;sup&gt;3&lt;/sup&gt;) but significantly higher monomer elution (50.5-87.4 μmol/L) compared with LU (36.1 μg/mm&lt;sup&gt;3&lt;/sup&gt;, 7.6 μmol/L), except for ND, which had the highest sorption values (P&lt;.001). TC exhibited sorption values (23.6 μg/mm&lt;sup&gt;3&lt;/sup&gt;) that were intermediate between those of the definitive and interim 3D printed materials. Filler weight correlated negatively with sorption (r&lt;sup&gt;2&lt;/sup&gt;=.739) and solubility (r&lt;sup&gt;2&lt;/sup&gt;=.896) (P&lt;.001) but did not correlate with monomer elution.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;Sorption, solubility, and monomer elution were more influenced by the type of material than the printing orientation. Definitive 3D printed materials demonstrated","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144132587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The diagnostic template in the digital era: A technique for fabricating a diagnostic trial restoration by using a two-piece additively manufactured index.","authors":"Panagiotis Ntovas, Ourania Ladia, Maria Spanopoulou, John C Kois, Marta Revilla-León","doi":"10.1016/j.prosdent.2025.04.027","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.04.027","url":null,"abstract":"<p><p>Diagnostic trial restorations, traditionally fabricated from silicone or vacuum-formed matrices formed on gypsum or 3-dimensionally (3D) printed diagnostic casts, have been widely used for the intraoral verification of the virtual design of prosthetic or esthetic rehabilitations. A step-by-step digital workflow for fabricating trial restorations is presented that transfers the virtual treatment plan intraorally using a 2-piece 3D printed index that does not require a diagnostic cast. Additionally, the design enables sequential removal from the mouth without displacement of the trial restorations.</p>","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144132604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A digital workflow for implants in the esthetic zone: A clinical report from dentofacial diagnosis to cast-free prosthesis delivery with a 1-year follow up.","authors":"Chan Young Park, Seoung-Jin Hong, Kung-Rock Kwon, Kwantae Noh","doi":"10.1016/j.prosdent.2025.03.048","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.03.048","url":null,"abstract":"<p><p>Dental implants in the esthetic zone are always challenging because of high patient esthetic and functional expectations. However, the development of digital technology has improved diagnostic tools and simplified treatment procedures. This clinical report describes a fully digital workflow for esthetic implant-supported prostheses, including digital dentofacial analysis, restoration-driven implant surgery, soft tissue contouring, and cast-free definitive prosthesis delivery. The patient was recalled 1 year after the delivery of the definitive prosthesis. Without any pathologic or radiographic findings, the patient was satisfied with the esthetics and function.</p>","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144132583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the marginal gap and internal fit accuracy of 3D printed zirconia crowns using the triple scan protocol.","authors":"Rogina Mamdouh Hassan, Rewaa G AboELHassan, Amir Shoukry Azer","doi":"10.1016/j.prosdent.2025.04.036","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.04.036","url":null,"abstract":"<p><strong>Statement of problem: </strong>Zirconia restorations must achieve micrometer-level accuracy in both marginal and internal fit to ensure an adequate fit with the abutments and to reduce the likelihood of clinical failure. Limited research exists on the fit accuracy of 3-dimensionally (3D) printed zirconia crowns, hindering the confirmation of additive manufacturing's effectiveness in producing zirconia restorations.</p><p><strong>Purpose: </strong>The purpose of this in vitro study was to analyze the marginal gap and internal fit of zirconia crowns fabricated through 3D printing compared with those manufactured by traditional milling.</p><p><strong>Material and methods: </strong>A mandibular typodont tooth was prepared to receive a monolithic zirconia crown, and 24 epoxy resin replicas were obtained and scanned with a dental laboratory scanner. Using a computer-aided design (CAD) software program (Dental CAD 3.0; evoked GmbH), 24 identical zirconia crowns were designed and sent for additive (LithaCon 210 3y; Lithoz GmbH) and subtractive (Nacera Zirconia; Dental Direkt) manufacturing. The triple scan protocol was used to evaluate the marginal gap and internal fit of all zirconia specimens. All scans were obtained using a laboratory optical scanner (Medit T710; Medit Corp). The resulting STL files of each specimen were superimposed and analyzed using a 3D analysis software program (Medit Design v.2.1.4; Medit Corp). Heat maps were generated to represent all deviations. An independent (nonpaired) t test was performed to compare the fit of crowns fabricated with both techniques (α=.05).</p><p><strong>Results: </strong>The 3D printed zirconia crowns exhibited a significantly higher marginal gap (87.7 ±7.4 µm) compared with the milled crowns (57.5 ±7.0 µm) (P<.05). Similarly, the internal gap was greater in the 3D printed group (107.4 ±4.9 µm) than in the milled group (86.6 ±7.6 µm) (P<.05).</p><p><strong>Conclusions: </strong>While 3D printed zirconia crowns demonstrated higher marginal and internal gap values compared with the milled crowns, both types were within clinically acceptable limits.</p>","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144132584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparing the performance of ChatGPT 4o, DeepSeek R1, and Gemini 2 Pro in answering fixed prosthodontics questions over time.","authors":"Mohammadjavad Shirani","doi":"10.1016/j.prosdent.2025.04.038","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.04.038","url":null,"abstract":"<p><strong>Statement of problem: </strong>The accuracy of DeepSeek and the latest versions of ChatGPT and Gemini in responding to prosthodontics questions needs to be evaluated. Additionally, the extent to which the performance of these chatbots changes through user interactions remains unexplored.</p><p><strong>Purpose: </strong>The purpose of this longitudinal repeated-measures experimental study was to compare the performance of ChatGPT (4o), DeepSeek (R1), and Gemini (2 Pro) in answering multiple-choice (MC) and short-answer (SA) fixed prosthodontics questions over 4 consecutive weeks after exposure to correct responses.</p><p><strong>Material and methods: </strong>A total of 40 questions (20 MC and 20 SA) were developed based on the sixth edition of Contemporary Fixed Prosthodontics. Following a standardized protocol, these questions were posed to ChatGPT, DeepSeek, and Gemini on 4 consecutive Saturdays using 10 independent accounts per chatbot. After each session, correct answers were provided to the chatbots, and, before the next session, their memory and history were cleared. Responses were scored as correct (1) or incorrect (0) for MC questions and correct (2), partially correct (1), or incorrect (0) for SA questions. Weighted accuracy was calculated accordingly. The Kendall W coefficient was used to assess agreement among the 10 accounts per chatbot. The effects of chatbot type, time (week), and their interaction on performance were analyzed using generalized estimating equations (GEEs), followed by pairwise comparisons using the Mann-Whitney U test and Wilcoxon signed-rank test with Bonferroni adjustments for multiple comparisons (α=.05).</p><p><strong>Results: </strong>All chatbots showed significant reproducibility, with Gemini exhibiting the highest repeatability for SA questions, followed by ChatGPT for MC questions. Accuracy ranged between 43% and 71%. ChatGPT and DeepSeek demonstrated significantly better performance in MC questions compared with Gemini (P<.017). However, in the third week, Gemini outperformed DeepSeek in SA questions (P=.007). Over time, Gemini showed continuous improvement in SA questions, whereas DeepSeek exhibited a performance surge in the fourth week. ChatGPT's performance remained stable throughout the study period.</p><p><strong>Conclusions: </strong>The overall accuracy of the studied chatbots in answering MC and SA prosthodontics questions was not satisfactory. Among them, ChatGPT was the most reliable for MC questions, while ChatGPT and Gemini performed best for SA questions. Gemini (for SA questions) and DeepSeek (for MC and SA questions) demonstrated improvement after exposure to correct responses.</p>","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144132585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Guided versus non-guided fiber post removal: A systematic review and meta-analysis of the accuracy, efficiency, and dentin preservation of static navigation techniques in the removal of fiber posts.","authors":"Mohamad Elabdalla, Farshad Khosraviani, Shahryar Irannejadrankouhi, Niloofar Ghadimi, Turgut Yağmur Yalçın, Shaheen Wathiq Tawfeeq Al Hajaj, Mahmood Dashti","doi":"10.1016/j.prosdent.2025.04.044","DOIUrl":"https://doi.org/10.1016/j.prosdent.2025.04.044","url":null,"abstract":"<p><strong>Statement of problem: </strong>Fiber posts have been frequently used to restore endodontically treated teeth because of their favorable esthetic and mechanical properties. However, their removal, especially when fractured or debonded, poses a considerable clinical challenge. Conventional techniques for fiber post removal can be time consuming, risk excessive dentin loss, and lead to unpredictable deviations from the original canal path. With the emergence of guided technologies, their potential advantages over non-guided methods in terms of accuracy, dentin preservation, and efficiency require clarification.</p><p><strong>Purpose: </strong>The purpose of this systematic review and meta-analysis was to evaluate whether guided techniques improve the accuracy of fiber post removal from endodontically treated teeth compared with non-guided approaches by focusing on time spent, dentin loss, and deviation.</p><p><strong>Materials and methods: </strong>A systematic search limited to publications up to October 2024 was conducted in 5 databases (PubMed, Scopus, Scopus Secondary, Embase, and Web of Science). Specific keywords included variations of \"fiber post\" and \"guided.\" After removing duplicates and applying inclusion criteria (studies testing guided fiber post removal with reported time, dentin loss, and/or deviation), 6 experimental studies remained for quantitative synthesis. Two independent reviewers evaluated eligibility, and a third resolved disagreements. Data extracted included sample sizes (ranging from 8 to 60 teeth per study), operator experience, measurement methods (digital imaging, cone beam computed tomography (CBCT), 3-dimensionally (3D) printed guides, and microscopic assessment), and outcomes. To assess the risk of bias, the revised JBI critical appraisal tool was used. Meta-analyses were performed using random-effects models, computing pooled means, standard mean differences (SMD), and 95% confidence intervals (CI). Heterogeneity was evaluated with the I² statistic (α=.05).</p><p><strong>Results: </strong>From the 5 included studies, guided techniques showed a pooled mean time spent of 3.47 minutes (95% CI, 1.70 to 5.25) and a deviation of 2.63 degrees (95% CI, 2.37 to 2.89). Dentin loss in the guided groups (3.83 mm³; 95% CI, -0.53 to 8.19) was statistically similar (P>.05). Comparisons between guided and non-guided groups revealed an SMD of -0.95 (95% CI, -3.19 to 1.29) for time and -2.06 (95% CI, -5.01 to 0.89) for dentin loss, with no significant differences noted (P>.05).</p><p><strong>Conclusions: </strong>Guided fiber post removal techniques demonstrated statistically significant improvements in accuracy, specifically in angular and linear deviations. However, differences in dentin loss and procedure time between guided and non-guided approaches were not statistically significant. Additional standardized, large-scale studies are necessary to comprehensively evaluate the clinical benefits of guided techniques.</p>","PeriodicalId":16866,"journal":{"name":"Journal of Prosthetic Dentistry","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144132603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}