The International journal of prosthodontics最新文献

Purpose: The present study aimed to compare sagittal condylar inclination (SCI) values obtained by three different methods-interocclusal wax recording, panoramic radiography, and electronic axiography (Cadiax-Compact 2).

Materials and methods: A total of 15 adults participated in this study. For the interocclusal recording, SCI was determined using protrusive interocclusal wax records, which were transferred to a semi-adjustable articulator. Panoramic radiographs were obtained and SCI values were measured by tracing the radiographic images. Extraoral tracings were recorded using a Cadiax-Compact 2. After a paraocclusal tray was fixed intraorally, each participant was instructed to perform three protrusive mandibular movements, and the average SCI values were calculated. The paired t-test was used to compare the SCI values of the right and left condyles. Pearson correlation analysis was performed to assess the relationship between the values obtained by the different methods, with a significance level set at p<0.05.

Results: No statistically significant difference was observed between right and left condyles for any of the three methods (p>0.05). The highest correlation was found between panoramic radiography and Cadiax-Compact 2, while moderate correlation was observed between interocclusal recordings and the other two methods. Interocclusal recordings yielded the lowest SCI values, while Cadiax-Compact 2 showed the highest.

Conclusion: Although panoramic radiography, and Cadiax-Compact 2 demonstrated strong correlation, interocclusal records showed moderate agreement and lower SCI values. However, considering the influence of functional movements, interocclusal recordings remain valuable for dentate patients. However, panoramic radiography can be a practical alternative in cases with limited neuromuscular control or a strong gag reflex.

Purpose: Large language models (LLMs) show promise in dental education, but their performance on specialized implantology knowledge is unclear. This study compared the accuracy and response times of six LLM configurations on an implantology MCQ dataset to guide optimal model selection.

Materials and methods: We administered 675 single-best-answer MCQs from a standard oral implantology question bank to six LLM setups in May 2025, including two OpenAI models (o3 and GPT-4o), two Microsoft Copilot modes (Deep and Quick, both based on o3-mini), and two Google Gemini variants (Flash and Pro). An independent assessor delivered questions in batches of ten using a uniform prompt, recorded each model's answers, and measured elapsed time per batch. Accuracy was the percentage of correct answers; response time was averaged across batches. χ² tests compared accuracy, and ANOVA compared response times.

Results: Accuracy varied significantly (p = 0.001). Gemini Pro (83.1%) and o3 Any blinded information will be available then. (82.4%) achieved the highest rates, outperforming GPT-4o (76.9%). Copilot Deep (77.8%) did not significantly exceed Copilot Quick (75.1%). Deep reasoning models (o3, Gemini Pro) averaged 4-5 s per batch, while lightweight variants (Copilot Quick, Gemini Flash, GPT-4o) responded in under 1 s (p < 0.001). All models uniformly failed questions requiring precise epidemiological or contraindication data.

Conclusions: Deep-reasoning LLMs deliver superior implantology MCQ accuracy at the cost of modestly longer inference times. Lightweight models offer near-instant responses with slightly lower accuracy. Aligning model choice to task complexity can optimize speed, cost, and diagnostic precision in implantology education and practice.

Objective: The present study aimed to identify the chronic diseases present in Brazilian older adults that are associated with total edentulism.

Materials and methods: This study is characterized as cross-sectional and population-based. The database from the last National Health Survey (NHS) in Brazil was used to conduct it. The study population consisted of older adults aged 60 years or older. The chronic diseases analyzed were hypertension, diabetes, high cholesterol, heart disease, stroke, asthma, rheumatism, back problems, musculoskeletal disorders, depression, schizophrenia, chronic lung diseases, cancer and kidney failure. The Chi-squared test was initially used in the data analysis. Then, adjusted prevalence ratios were estimated using Poisson regression with robust variance, including all covariates in the model to identify chronic diseases associated with total edentulism.

Results: A total of 22,728 older adults were included. The prevalence of total edentulous older adults was 31.7%. The most prevalent chronic diseases in these completely edentulous older adults were hypertension (55.5%), back problems (29.1%) and high cholesterol (26.6%). Total edentulism in older adults was associated with the female sex (p<0.001), being older (p<0.001), illiterate (p<0.001), those who do not have health insurance (p<0.001), older adults who have hypertension (p<0.001), diabetes (p=0.004), and those who suffered a cerebrovascular accident (CVA) (p<0.001).

Conclusion: It is concluded that total edentulism in older adults is associated with worse socioeconomic conditions and with individuals who have hypertension, diabetes and who have suffered a stroke.

Purpose: Aims to examine the high-speed sintering and conventional methods on To evaluate the effect of high-speed and conventional sintering on the biaxial flexural strength of high-translucent zirconia materials before and after artificial aging [Low temperature degradation (LTD)].

Materials and methods: A total of 156 zirconia samples A total of 156 zirconia specimens (disc-shaped, 12 mm diameter × 1.2 mm thickness) were prepared from three materials (4Y-TZP: Nacera DD-cube-ML-HT; 5Y-TZP: Nacera DD-cube-X2ML-HT; 6Y-TZP: Nacera Pearl-Q3-ML-HT; n = 52 each). Specimens were sintered using either a high-speed sintering protocol (1580 °C; n = 26) or a conventional sintering protocol (1450 °C; n = 26). The samples Specimens were artificially aged (LTD) (10 h, 134 °C; n = 13) or not aged (control group). Microhardness and biaxial strength of the samples were assessed. were measured. Phase composition was characterized using XRD Microhardness and biaxial flexural strength were measured, and phase composition was characterized using X-ray diffraction (XRD) with Rietveld refinement. ANOVA, post-hoc Tukey, The and Shapiro-Wilk tests were performed (p < 0.05). The survival probability was determined using Weibull analysis.

Results: Conventional sintering of 4Y-TZP and 5Y-TZP zirconia resulted in similar mechanical characteristics after LTD. The Weibull modulus of high-speed sintered zirconia specimens decreased following LTD. Among the groups, 4Y-TZP specimens exhibited the highest stability and strength, whereas 6Y-TZP showed the lowest performance. In Rietveld and XRD analyses, 4CL exhibited highest stability with an 80.7% t-phase ratio and 1709.79 MPa strength, while 6CL showed the lowest performance with 62.9% and 624.89 MPa.

Conclusion: Speed sintering and low-temperature decomposition LTD can lead to a degradation of the physical and mechanical properties of zirconia, potentially compromising its durability in clinical applications. An optimal sintering duration seems to enhance mechanical strength by preserving a high content of the tetragonal phase, thereby potentially extending the clinical lifespan. This situation underscores the necessity for more extensive research regarding the application of next-generation zirconia ceramics in clinical environments. Conventional sintering preserved higher flexural strength and phase stability compared to high-speed sintering under LTD conditions, and therefore appears more favorable for long-term performance.

Purpose: To evaluate the antibiofilm action of 2.5 mg/mL peracetic acid (PA), 0.5 mg/mL cetylpyridinium chloride (CPC), and 160 mg/mL N-acetylcysteine (NAC) against multispecies biofilm of Streptococcus mutans, Staphylococcus aureus, Candida albicans, and Candida glabrata developed on surfaces of heat-polymerizing acrylic resin (AR) and cobalt-chromium (Co-Cr) alloy.

Materials and methods: A multispecies biofilm was grown on the surface of AR and Co-Cr specimens (Ø 12 × 3 mm). After biofilm maturation, the specimens were immersed in experimental solutions and evaluated through biofilm viability (CFU; n = 9), biofilm metabolic activity (XTT; n = 9), biofilm-covered areas (live/dead; n = 2), effects on the extracellular polymeric substance (EPS; n = 2), and biofilm morphology (n = 1). Data were analyzed by ANOVA and Tukey post-hoc test or Kruskal-Wallis followed by Dunn post-hoc test (α = .05).

Results: Overall, all evaluated solutions impacted biofilm viability. PA presented wider activity by reducing CFU of all microorganisms on both surfaces, XTT (P < .001) and live/dead (P < .001). NAC had a notorious effect in reducing the viability of bacteria without affecting the yeasts. NAC reduced XTT on AR (P = .006) and Co-Cr (P = .003) but did not reduce the aggregated biofilm layer. CPC had a distinct effect, being most effective in reducing CFU on AR compared to the Co-Cr surface. However, it did not influence XTT or the amount of residual aggregated biofilm.

Conclusions: PA provided the greatest antibiofilm action, while CPC and NAC showed intermediate action. Nonetheless, no solution was able to completely remove the biofilm adhered to the surfaces of heat-polymerizing AR and Co-Cr alloy.

Purpose: To evaluate the accuracy of intraoral scanning (IOS) impressions for multiple implants by comparing them to analog impressions.

Materials and methods: Patients with three adjacent implants in partially edentulous arches were recruited. For each arch, IOS impressions were obtained. Using the analog splinted-impression technique, casts were obtained and scanned with an extraoral scanner. Using metrology software, the distances and angles between the implants were measured in all IOS and analog impression STL files. The absolute values of the distance and angular deviation were calculated and analyzed by comparing the two impression methods.

Results: A total of 34 patients with partially edentulous arches were enrolled. The distance deviation between the IOS and analog impressions was 85.09 ± 58.73 µm, which was significantly lower than the clinically acceptable threshold for error (150 µm; P < .001). The angular deviation was 0.515 ± 0.426 degrees. Distance deviations were significantly correlated with the interimplant distances (r = 0.384, P = .001) and angulations (r = 0.278, P = .022).

Conclusions: For prostheses supported by multiple implants in partially edentulous arches, the distance deviation between the IOS and analog impression was within the clinically acceptable range of misfit and increased with increasing interimplant distance and angulation.

This article presents an efficient method for fabricating a full-arch implant prosthesis within 1 day using a verification index through a 3D-printed surgical guide. The technique involves the use of simple impression copings and laboratory analogs to ensure accurate prosthesis placement. Directly using 3D-printed surgical guides as a verification index simplifies and streamlines the procedure, offering a significant clinical advantage. This approach provides a clinically relevant advancement in prosthodontic practice by demonstrating a practical and instructive approach to enhance treatment outcomes.

Purpose: To evaluate the effect of post-printing treatment conditions, including curing time, on the optical and mechanical properties of temporary crown (TC) materials.

Materials and methods: A total of 108 specimens of TC materials (PowerResins Temp, PioNext Temporary Restoration Resin) and conventional polymethyl methacrylate (PMMA) were produced. The 3D-printed specimens were post cured for different time durations (0, 15, 30, and 45 minutes) (n = 11). During the evaluation of optical properties, color measurement and translucency measurement were performed, while surface hardness and flexural strength were tested mechanically. For structural characterization, analyses were carried out using Fourier transform infrared and Raman spectroscopy (FTIR) and scanning electron microscopy. Data were analyzed with ANOVA (P = .05).

Results: The highest color change was observed in the PioNext Temporary Restoration Resin cured for 15 minutes (11.81 ± 0.95), while the lowest was in the noncured PowerResins Temp group (1.93 ± 0.38; P < .001). Hardness and flexural strength increased significantly with curing duration (P < .001). FTIR analysis revealed optimal polymerization at 30 minutes, suggesting this duration offers a clinically favorable balance of mechanical, optical, and chemical properties.

Conclusions: Both post-curing times and different production techniques affected the microstructural, optical, and mechanical properties of the tested samples. Although longer curing time improved the mechanical properties of the materials, chemical analysis showed that 45 minutes of curing negatively affected the polymerization. Moreover, curing for 30 minutes had a positive effect on the mechanical properties without changing the chemical structure of the samples.

Purpose: To investigate the effect of cleaning procedures (ultrasonic, autoclaving) and aging methods (24 hours, 90 days, and thermocycling) on the shear bond strength (SBS) between alumina-particle air-abraded titanium (Ti) and zirconia (Zr; 3Y-, 4Y-, and 5Y-TZP) specimens luted with phosphate monomer-containing adhesive systems and resin-based composite.

Materials and methods: Lab-side-fabricated test specimens were prepared by bonding different Zr plates to Ti cylinders using a resin-based composite. The cleaning procedures included ultrasonic cleaning and purging (UUP) or two stages of purging and autoclaving (PPA). The specimens were then aged for 24 hours, 90 days, or had to endure thermocycling.

Results: Autoclaving significantly improved SBS (F [27,231] = 17.265, P < .001) compared to no cleaning and three-stage disinfection.

Conclusions: No differences were identified with regard to Zr or aging methods. Bond strength initially benefits from autoclaving but continuously approaches the comparative values over longer periods.