The International journal of prosthodontics最新文献

Purpose: To assess whether a health education video increased prosthodontic treatment demand for replacing missing teeth compared to a traditional health education (IEC) leaflet among patients visiting a university dental care center in Saudi Arabia.

Materials and methods: A nonrandomized educational intervention was conducted among patients with missing teeth. A total of 350 participants were divided equally into two health-education intervention groups: leaflet group and video group. Two major variants were ascertained: demand for prosthodontic dental care and awareness (knowledge) about the importance of replacing missing teeth. These two variants were studied for the difference in the scores between base line and at the end of the program (after 3 months). Bivariate analysis was done with chi-square test, McNemar chi-square test, and Wilcoxon matched-pairs tests, and finally binary logistic regression analysis was done.

Results: The final analysis included 324 participants. There was improvement in both knowledge and demand for prosthodontic care in both the groups after health education, but a statistically significant improvement in demand for dental care was observed in the video group compared to the leaflet group (42.9% vs 63.2%). Logistic regression analysis identified that missing teeth in the anterior region and being in the video group were two significant factors associated with increased demand for care.

Conclusions: The health education video method was found to be a more effective method compared to leaflets in improving knowledge and demand for replacing missing teeth.

Purpose: To evaluate the published literature on tooth-tissue supported removable partial dentures (RPDs) and determine the attachment system that provides the best clinical outcome.

Materials and methods: A comprehensive search of studies published up to November 2021 was performed in the PubMed/MEDLINE, Web of Science, and Cochrane Library databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. The study protocol was approved and was registered in the International Prospective Register of Systematic Reviews (PROSPERO: CRD42021268449). The PICO question was, 'What is the best attachment system used in Kennedy class I and II removable partial dentures?'

Results: The search identified 871 articles, of which 21 met the inclusion criteria. The evaluation period in the studies ranged from 3 to 282 months. A total of 1,357 patients were included, of which 526 used prostheses with attachments. The mini SG attachment (extracoronal) was the most commonly used attachment, and the survival rate ranged from 37% to 98.1% in 10 studies, with no significant differences between the systems. Among the 10 studies selected for quantitative analysis, the meta-analysis revealed an overall failure rate of 16.6% (95% CI: 10.4% to 25.4%) and heterogeneity of I² = 65.725 (q value: 26.258, P = .002).

Conclusions: Clinical studies comparing different attachment systems for rehabilitation are lacking. Our findings suggest that attachment-retained RPDs have good retention and better esthetics than conventional RPDs, and the extracoronal attachment system is the most viable choice for treatment at the free end.

Purpose: To propose and evaluate standardized polishing protocols for in vitro experiments using a custommade apparatus under controlled force to create consistent surface roughness on titanium and zirconia discs.

Materials and methods: A total of 160 discs were manufactured with a diameter of 10 mm, 80 titanium (Ti) and 80 zirconium oxide (Zr). Specimens were categorized into two groups: controlled force (CF) and without controlled force (WCF). Specimens in the CF group were polished with a custom apparatus incorporating a tension gauge on the Ti and Zr disc surfaces to achieve consistent roughness. The WCF group was polished without the use of a tension gauge. Each group had four subgroups (n = 10): control/machined with no polishing (C), rough (R), smooth (S), and very smooth (VS). The subgroups were processed using a sequence of diamond-impregnated polishing burs and polishing paste.

Results: The CF group showed consistent surface roughness and a gradual decrease in surface roughness. Control in Ti (Ra = 6.5 ± 0.03 μm) and in Zr (Ra = 5.4 ± 0.04 μm); R in Ti (Ra = 3.5 ± 0.06 μm) and in Zr (Ra = 3.2 ± 0.07 μm); S in Ti (Ra = 1.5 ± 0.04 μm) and in Zr (Ra = 1.1 ± 0.06 μm); and VS in Ti (Ra = 0.05 ± 0.002 μm) and in Zr (Ra = 0.02 ± 0.005 μm). There were significant differences for R, S, and SV under CF and WCF in Ti and Zr surfaces.

Conclusions: The specimens polished under control force produced significantly more uniform surface roughness than those polished without controlled force and were produced with a higher degree of consistency.

Purpose: To examine the long-term performance of bonded all-ceramic restorations, specifically veneers, in patients with amelogenesis imperfecta (AI). There are few studies of long-term outcomes using a minimally invasive procedure in these patients. This aspect is essential when treating young patients. All-ceramic restorations, especially veneers, offer a more tissue-preserving treatment but rely on successful bonding. However, due to the defect enamel in AI patients, the bond strength is lower.

Materials and methods: A retrospective evaluation of 40 subjects with AI (26 women, 14 men) was provided with a total of 360 bonded restorations (282 veneers, 78 crowns). The restorations were evaluated according to complications, survival, and success rate.

Results: The patients were observed up to 25.3 years (mean 15.4 ± 4.3 years). The mean age when receiving the restorations was 18.5 ± 4.2 years. In total, 59 (16.4%) restorations with prosthetic complications were made, 29 of which (8.1%) were remade (6 due to esthetic reasons, all in one patient) and 30 (8.3%) were recemented (60% caused by trauma). We found 11 teeth with caries and 3 with endodontic complications. The overall survival rate was 91.9%, and the overall success rate was 83.6%.

Conclusions: Bonded all-ceramic restorations with no active retention in AI patients have excellent performance. The most common complications were debonding and fractures. The treatment should be based on individual indications and be preceded by a multidisciplinary approach.

Purpose: To investigate the resistance of an implant crown telescopically engaged to a geometrically defined hexagonal abutment with and without cement under compressive dynamic cyclic fatigue loading.

Materials and methods: 40 crowns, 9 mm in height, were cast from prefabricated plastic copings, each telescopically engaged to a 3-mm-high machined hexagonal abutment. 20 crowns were retained with zinc phosphate cement, and 20 crowns were retained with a screw. A vertical load of 15 kg was applied to all samples under oscilla)on. A Periotest was used to measure the mobility of the implant crown in Periotest values (PTV). Test endpoints were defined by the following: fatigue cycles ≥ 20 million; crown PTV > 10; or if samples became visibly loose or component fracture.

Results: Cement-retained crowns failed on average at 2.60 x 106 cycles ± 2.27, while screw-retained crown samples failed at 2.17 x 106 cycles ± 1.27 with no significant difference (P > .05). Implant and abutment screw fractures were the most prevalent mode of failure in the cement-retained group, while in the screw-retained group, failures were caused by the loosening of one or both screw joints. The rate of increase in PTV was higher in the screw-retained group than in the cement-retained group.

Conclusions: Under the experimental conditions, an implant crown telescopically engaged vertically to a 3-mm-tall hexagonal abutment, under compressive dynamic cyclic fatigue loading with or without cement, demonstrated no differences in resistance or failure outcomes. A cement-retained implant crown with telescopic engagement to the abutment is more rigid, resulting in more implant and abutment screw fractures than loosening.

Purpose: To assess the clinical performance of CAD/CAM laminate veneers placed by a single operator and systematically evaluated for up to 10 years.

Materials and methods: A total of 197 laminate veneers fabricated using either feldspathic ceramics (VMII) or lithium disilicate ceramics (EmaxCAD) were followed up to 10 years in 32 patients. Technical, esthetic, and biologic findings of each restoration were evaluated using modified United States Public Health Service criteria. The survival and complication rates were assessed using Kaplan-Meier survival analysis and compared using log-rank test. Statistical significance was set at P < .05.

Results: The estimated Kaplan-Meier survival rate was 91.9% after the mean observation period. According to the ceramic system used, the estimated Kaplan-Meier survival rate amounted to 92.7% for EmaxCAD and 89.1% for VMII. Survival rates were significantly affected by the location of veneer according to log-rank test (P < .05). A range of survival rates between 83.3% and 98.6% were observed based on the location of veneer.

Conclusions: CAD/CAM laminate veneers milled from feldspathic or lithium disilicate ceramics have comparable long-term survival rates. Oral positioning affects the survival of veneers. Veneers of incisors have higher survival rates than the veneers of maxillary canines and premolars.

Purpose: To evaluate changes in color and translucency of stained and glazed monolithic lithium disilicates and zirconia after toothbrushing with conventional or whitening dentifrices followed by thermocycling.

Materials and methods: Samples (n = 20/material) from CAD/CAM (IPS e.max CAD [EC]) and pressable (IPS e.max Press [EP]) lithium disilicates and 5Y-PSZ zirconia (Prettau 4 Anterior [PA]) were prepared and received staining and glazing procedures. Aging was performed by toothbrushing with conventional (n = 10) or whitening (n = 10) dentifrices, followed by thermocycling simulating 5, 10, and 15 years. Color coordinates L*, a*, b*, , and C* and h° values were assessed with a spectrophotometer at baseline and after each aging period to calculate color changes (ΔE00), lightness (ΔL*), and translucency parameter (TP). Data were analyzed using three-way repeated measures ANOVA's followed by Sidak post-hoc test (α = .05).

Results: When comparing the dentifrices, EC and EP produced the greatest ΔE00 after 15 years with the whitening dentifrice (P < .05). Regardless of the dentifrice, PA showed greater ΔE00 than EC after 10 years (P < .05). When comparing the aging periods, EC and PA did not show differences in ΔE00 for both dentifrices (P ≥ .05). EC and EP produced an increased ΔL* after 15 years in the whitening group (P < .05). In the whitening groups, the ΔL* values of PA differ (P < .005) from those of lithium disilicates. Regardless of the experimental group, the TP values followed the inequality: PA < EC < EP (P < .05).

Conclusions: Overall, the color of stained and glazed monolithic lithium disilicates and zirconia changed under aging with greater effects for whitening dentifrice. Aging did not influence translucency.

Purpose: To evaluate the clinical survival and impact on oral health-related quality of life (OHRQoL) of immediate loading of implant-supported full-arch CAD/CAM-milled PMMA interim restorations.

Materials and methods: This was a practice-based prospective cohort study performed in a Portuguese dental clinic. Eleven patients received a total of 17 CAD/CAM fully implant-supported, screw-retained, full-arch restorations with milled PMMA and were followed up for 1 year. The primary outcome was prosthesis survival, determined with a modification of the California Dental Association score and a Kaplan-Meier survival function analysis. The secondary outcome was the patient quality of life, as defined by application of the OHIP-14-PT questionnaire and standardized effect size variation between two visits. Significance was set at 5%.

Results: Survival probability at 12 months was 76%, complete fracture of the prosthesis occurred in 17.6% of the cases, and small fractures without lab involvement occurred in 5.9% of cases. There was a significant improvement in OHRQoL between visit 1 and visit 4. The mean difference and effect size for total OHIP-14-PT score were -32.91 ± 3.68 and 3.66 (95% CI -1.83 to -5.80) respectively (P < .001* Wilcoxon matched paired rank test).

Conclusions: Fullarch implant-supported CAD/CAM-milled PMMA interim prosthesis seem to be a viable approach with good survival rate and great impact on patient OHRQoL.