European Journal of Prosthodontics and Restorative Dentistry最新文献

Purpose: The objective of this systematic review was to evaluate and compare the accuracy of digital impression techniques and conventional methods for full-arch implant impressions.

Methods: An electronic literature search in the databases Medline (Pubmed), Web of Science, and Embase was performed to identify in vitro and in vivo publications (between 2016 and 2022) directly comparing digital and conventional abutment-level impression techniques. All selected articles passed through the data extraction procedure according to defined parameters in inclusion and exclusion criteria. Measurements on linear, angular and/or surface deviations were performed in all selected articles.

Results: Nine studies met the inclusion criteria and were selected for this systematic review. 3 articles were clinical studies and 6 studies were in vitro. Accuracy difference mean values of the trueness up to 162+/-77μm between digital and conventional techniques were reported in the clinical studies and up to 43μm in laboratory studies. Methodological heterogeneity was observed in both, in vivo and in vitro studies.

Conclusions: Intraoral scanning and photogrammetric method showed comparable accuracy for registering implant positions in the full-arch edentulous cases. A tolerable implant prosthesis misfit threshold and objective misfit assessment criteria (for linear and angular deviations) should be verified in clinical studies.

Aim: The aim of this systematic review is to evaluate the relationship between prosthodontic treatment and temporomandibular disorders (TMD).

Materials and methods: Two clinical questions have been raised. Can prosthodontic treatment be used as a strategy to manage temporomandibular disorders? Is there any causal relationship between prosthodontic rehabilitation and the onset of TMD? A systematic search was performed in four medical databases to identify Clinical Trials (CT) and Randomized Clinical Trials (RCT) that could answer the two clinical questions.

Results: Any articles fulfilling the inclusion criteria were found. Therefore, the best available evidence on TMD management and aetiology is discussed in a scoping review with focus on the relationship with prosthodontic treatment.

Conclusions: Based on current scientific evidence, prosthetic rehabilitation cannot be proposed as a treatment option for TMD patients, based on the effectiveness of other more conservative options as well as the absence of association between features of dental occlusion and TMD. Thanks to the high neuro plastic adaptation skills of the stomatognathic system, prosthodontic rehabilitation cannot be identified as a direct cause of TMD, but clinicians should pay caution when performing relevant occlusal modifications.

Purpose: The aim of this systematic review was to explore the dental literature to identify high quality clinical studies that introduced methods of determining the vertical dimension of occlusion (VDO), and additionally to find studies which assessed alterations in the VDO.

Materials and methods: An electronic search of the literature was conducted through PubMed , Embase, and Cochrane Library databases referring to the determination and alteration of the VDO by 12/2021.

Results: A total of 215 records were obtained from the initial search. After the first two screenings, 33 studies were selected for inclusion. Correlations in the morphometric group ranged between r=0.18-0.87, p⟨0.05-0.001, correlations in the cephalometric group ranged between r=0.28-0.92, p⟨0.05-0.001, and correlations in the mechanometric group ranged between r=0.21- 0.75, p⟨0.05-0.01. Regarding the alteration of VDO, in all studies the increase ranged between 1.8-8 mm and the patients adapted .

Conclusions: No clear guidelines can be established yet, in relation to the determination and alteration of the VDO. There is no apparent benefit in using more invasive and complex methods compared to the use of the facial anatomical landmarks. Patient adaptation seems to be successful when the range of VDO increase was 1.8-6.0 mm.

This study investigated the effect of silane coupling agent and universal adhesive application on repair bond strength of resin-based composite after bur grinding. Microhybrid resin composite (Charisma Smart) blocks (N=80; 8x8x4 mm3) were prepared, aged (37°C; 1 month), roughened, etched and randomly divided into two groups. Silane was applied to half of the groups (Porcelain Primer, Bisco), before one of the following universal primers/adhesives was applied: a) Scotchbond Universal (3M), b) All-Bond Universal (Bisco), c) G-Premio Bond (GC), and d) Clearfil SE Bond (Kuraray). In each adhesive group half of the group was photo-polymerized. The blocks were repaired with the same size resin composite and segmented into beams. Half of the beams were subjected to micro-tensile bond test (1 mm/min), while the other half was aged (37°C; 6 months) prior to testing. Failure modes were analyzed using Scanning Electron Microscopy (SEM). Data were analyzed using repeated measures of ANOVA, Tukey's post-hoc, and paired t-tests (alpha=0.05). The silane application did not affect the repair bond strength regardless of photo-polymerization of the adhesive resin. The repair bond strength decreased significantly after 6 months when adhesive resin was not photopolymerized (p⟨0.05). Photo-polymerizing universal adhesives might ensure higher repair bond strength and its maintenance after aging.

Objectives: To evaluate the clinical performance of universal adhesives with self-etch mode regarding their functional monomer and HEMA contents.

Methods: The study involved 27 patients (108 restorations) aged between 34 and 69 (mean age: 53.8). Each restoration contained one of four different universal adhesives applied in self-etch mode: G-Premio Bond (HEMA-free, MDP and 4-MET containing), Xeno Select (HEMA and MDP-free), Tetric-n-Bond Universal (HEMA and MDP-containing) and Clearfil Universal Bond Quick (HEMA, MDP and amide monomers containing). The restorations were evaluated according to the FDI criteria at baseline, 6, and 12 months. The data were statistically analyzed using Friedman's and Kruskal-Wallis tests for significance in each pair (p⟨0.05).

Results: After 12 months, one restoration was lost in each of the G-Premio Bond and Clearfil Bond Quick groups. The success rate was 96.3% for both adhesives and 100% for Xeno Select and Tetric-n-Bond adhesives. There was no statistically significant difference between the four dentin adhesive groups among all the evaluation periods regarding any evaluation criteria. However, four universal adhesives showed clinically acceptable marginal discoloration and marginal deterioration in a few restorations.

Conclusion: Monomer contents of universal adhesives with self-etch mode had no significant effect on the success of restorations.

This study investigated the influence of mechanical cycling on screwed-in and tappedin implants restored with screw-retained metallic crowns. Three implant-abutmentcrown systems were evaluated: T1 (multi abutment) and T2 (standard abutment) received tapped-in abutments and S received a screwed-in abutment. The specimens were subjected to two million cycles of 0-150 N load, at 2 Hz, 30° inclination in a dry medium, and torque evaluation. Survival and removal torque were analyzed using chisquare, ANOVA, followed by Tukey's test. Differences between installation and removal torque were determined using a T-test for dependent samples. Analyses were performed in SPSS, considering α = 0.05. All specimens survived mechanical cycling in S, 40% in T1, 80% in T2 (p=0.008). Failures occurred due to loosening of the crown screw. A significant decrease in torque (p=0.000) was found. Group T1 had the lowest removal torque (1.6 ± 0.84 N.Cm²), followed by T2 (3 ± 1.49 N.Cm²) and S (6.3 ± 1.16 N. Cm²), and a statistical difference was found between Groups T1 and S. Both types of implantabutment connections were stable and can be considered for rehabilitative treatment, but failure and removal torque were influenced by the design of prosthetic abutment. Crowns were more susceptible to becoming loose in tapped-in systems.

Objective: The force-distance power law for dental magnets had been unresolved until a theoretical study found that only even inverse powers were allowed; for simple magnets inverse fourth power was the only possibility. It remained to demonstrate that this indeed did apply to real magnets, the present purpose.

Methods: The force exerted by a series of real dental magnets to a large steel plate, and in a few cases to dental magnet keepers, as a function of distance was recorded. Curve-fitting of that data was explored. using the equation previously used for long dipoles, but allowing the power to be a free parameter. An index of 4 was the only feasible value. Corresponding fitted parameter values were then examined in relation to magnet design and each other.

Results: The theoretical power law index was confirmed to be 4. For a satisfactory fit, a 'polar offset' and a 'stretch power' were again required to better approximate the experimental results. Polar offset appears to be a function of apparent pole strength; stretch power less clearly so.

Significance: The motivating question is settled.

Objective: To compare the antimicrobial effect of bioceramic endodontic cements with and without silver nanoparticles on Enterococcus faecalis.

Materials and methods: Six groups were evaluated (n=8), and divided according to the materials: MTA Flow + AgNP ; MTA Flow Group; Bio C Repair + AgNP; Bio C Repair; PBS Cimmo + AgNP; PBS Cimmo. The groups were maintained for 72 h in the suspension of Enterococcus faecalis in Simulated Body Fluid (SBF). Samples of 100 μL were removed from the suspension at 0, 24, 48 and 72 h and seeded in triplicate in a Petri dish. Colony forming units (CFU) were counted using a colony counter. All procedures described were performed in a laminar flow chamber. Two-way ANOVA followed by Tukey's post hoc test and paired t-test were used for statistical analyses (α = 0.05).

Results: The addition of silver nanoparticles resulted in a statistically significant difference for MTA and CIMMO PBS cements (p⟨0.05), with the lowest bacterial growth being shown by the MTA group. For all groups, only the times of 48 and 72 h presented results without differences.

Conclusion: The addition of silver nanoparticles to bioceramic cements was efficient to promote an acceleration of bacterial death.

Purpose: To investigate antifungal and mechanical properties after the impregnation of Dimethyl Amino-ethyl Hexa-decyl Di-methacrylate (DMAHDM) alone or in combination with Nystatin in polymethylmethacrylate.

Methodology: The control group was fabricated by mixing powder and liquid of PMMA at the ratio of 2.5:1 g/mL. The DMAHDM was added to PMMA liquid and were mixed with PMMA powder. The Nystatin (500,000 International Units (IU)) was mixed with PMMA powder, whereby the composite powder was mixed with the DMAHDM-based liquid. The prepared specimens were tested for fungal adhesion testing (at days 1 and 30), impact strength and flexural strength. Oneway ANOVA post-hoc Tukey's test were used for statistical analysis.

Results: Statistical analysis for the adhesion assay revealed that the antifungal activities of unaged and aged specimens in experimental groups were statistically significant as compared to control group A. The groups containing DMAHDM with Nystatin have shown statistically reduced flexural strength. The impact strength test revealed that groups containing 20% DMAHDM alone and DMAHDM with Nystatin showed statistically reduced impact strength compared to the control group.

Conclusion: Antifungal activities of experimental PMMA resin was increased. The addition of DMAHDM alone in PMMA resin has no deleterious effects on impact and flexural strength, however, at higher concentration values were reduced.

This in-situ study aimed to evaluate the chromatic stability, microhardness, and surfacefree energy of chemically activated acrylic resin (CAAR) samples. Eighty CAAR samples were made and each volunteer (n = 20) received two palatal plates with two sides of groups (without and with glaze application). The samples were exposed to two conditions: the control condition (sucrose 30%) and the test condition (sucrose 30% and 0.12% chlorhexidine). The volunteers used the first palatal device (control condition) for seven days and the second palatal device (test condition) for another seven days, with a seven-day break between them. Then, the ΔΕ00, microhardness, and surface-free energy tests were performed. Analysis of Variance and the Tukey test were used (α = 0.05). The control group with glaze showed higher ΔΕ00 compared to the group without the glaze. The test group with glaze had less ΔΕ00 than their respective controls. In both periods, when the glaze was applied, higher microhardness values were found for all groups. Groups with glaze showed lower roughness and higher surface-free energy than groups without the glaze. The values obtained in this study were satisfactory, showing the clinical efficacy of glaze and the use of 0.12% CH for maintaining the physical and mechanical properties of CAAR.