European Journal of Prosthodontics and Restorative Dentistry最新文献

Objective: The ability of six curing lights to photocure four resin-based composites (RBCs) in a mold simulating a cavity was compared visually.

Materials and methods: Four RBCs were photocured using the: Woodpecker B for 2x10s, SmartLite Pro 2x10s, Valo Cordless 2x10s, Valo Cordless 2x3s Xtra power, Valo X 2x10s, Valo X 2x5s Xtra power, PowerCure 2x3s mode, Monet 1x1s and Monet 3x1s, in a mold representing a molar Class II restoration. Immediately after photocuring, the RBC specimens were immersed in a solvent to remove the uncured RBC, after which they were photographed and de-identified. Using a REDCap survey, these images were compared visually to compare the ability of the LCUs to photocure the restorations.

Results: There were significant differences in how well the LCUs had photocured the RBCs. The SmartLite Pro and Valo X used for two 10s exposures produced restorations rated as the best cured, and the Monet used for 1 s was rated the worst.

Conclusions: There were visually apparent differences in how well the LCUs could photocure the RBCs. The Monet used for 1 second produced the worst results for all four RBCs.

Introduction: The physical condition of the tip and the irradiance of LCUs used in dental offices in the United States and Canada was assessed twice.

Methods: The tip irradiance and physical condition of the tip of 1067 LCUs from 544 dental clinics were assessed twice between 2015 and 2021 using the CheckMARC (BlueLight) radiometer. The irradiance values were compared by paired Student's t-test (α = 0.05).

Results: There was a wide range of irradiance values (200 to 3,777 mW/cm²). At the first assessment, only 26% of the LCUs had no visible damage or debris on the LCU tip. When retested up to 36 months later, 70% of the LCUs had their tip damage or debris issues entirely or partially resolved. 2.6% of the LCUs delivered an irradiance below 500 mW/cm² on the first and 1.6% on the second assessments. For the 5 brands that had a sufficient sample size, it was concluded that the irradiance increased when the tip damage or presence of tip debris was resolved.

Conclusions: Initially, most LCUs (74%) had at least one problem related to damage or debris on the LCU tip. The irradiance increased when the tip damage or debris was resolved.

To evaluate the effect of calcium hydroxide (CH), sodium ascorbate (SA) and sodium thiosulfate (ST) filling the pulp chamber on color stability and longevity of teeth after internal bleaching. Crowns of bovine incisors were submitted to internal bleaching and divided into groups according the material used in the pulp chamber: Control, CH, SA, ST. Each group was divided into two subgroups according to the time to perform restorative procedures (7 or 15 days). Color measurement was performed with a spectrophotometer at nine periods. The darkening (ΔE) values were calculated. The Mann-Whitney test was used to statistically analyze the data (p ⟨ 0.05). After bleaching, ΔE values were higher than 3.5, showing that the procedure was effective. After 24 hours, no difference was observed between groups. After 7 days, SA showed higher ΔE than the control group (p ⟨ 0.05). CH and TS did not differ from the control group. In restorations performed after 7/15 days, SA group showed higher values of darkening after 1 and 4 months than the control group (p ⟨ 0.05). SA induced perceptible darkening after bleaching and should not be used to fill the pulp chamber. ST and CH show color stability and longevity after 12 months.

Objective: To evaluate the effect of different agitation methods on apical extrusion of 1.5% sodium hypochlorite (NaOCl) in an ex vivo model of immature teeth.

Methods: Sixty extracted human inferior incisors were prepared to simulate immature teeth and embedded in an artificial root socket made of silicone impression material. The teeth were then divided into four groups: Conventional needle irrigation (CNI) alone, CNI supplemented with Ultrasonic Irrigant Activation (UIA), EasyClean (EC), or XP-endo Finisher (XPF). Extruded NaOCl was collected, reacted with m-cresol purple, and its absorbance values were measured. The data were statistically analyzed using One-way analysis of variance with a significance level of 5%.

Results: All groups showed apically extruded irrigating solution, and the mean volumes of extruded NaOCl did not differ significantly between any of the test groups (p⟩0.05).

Conclusion: The activation of 1.5% NaOCL by UIA, EC, or XPF as supplementary to CNI does not promote greater apical extrusion when compared to CNI alone in simulated immature teeth.

Introduction: Digital dentistry and advanced ceramic materials have been widely used but which material has a better esthetically durable outcome needs to be evaluated. The purpose of this systematic review and meta-analysis was to evaluate the difference in the translucency of CAD zirconia-reinforced lithium silicate and CAD lithium disilicate glass ceramics after being subjected to artificial aging.

Material and methods: Two independent reviewers searched the MEDLINE/ PubMed, Embase, and EBSCO databases and the Google Scholar search engine for in-vitro studies published from January 2010 to May 2023 to identify relevant studies measuring the translucency of CAD ZLS and CAD lithium disilicate glass ceramics after being subjected to different artificial aging conditions using the coffee solution, 4% acetic acid, distilled water and UV aging.

Results: For qualitative synthesis, 10 studies were included. A statistically significant difference was observed between CAD zirconia-reinforced lithium silicate and CAD lithium disilicate glass ceramics (P⟨0.05, mean difference=-0.25 [-0.38,-0.11]). Translucency of CAD ZLS was less than CAD lithium disilicate glass ceramics.

Conclusions: Artificial aging has decreased the translucency of glass ceramics. For fixed prosthetic rehabilitation clinicians can opt for CAD lithium disilicate glass-ceramic as a more esthetically pleasing and durable material in oral environment.

Introduction: Bulk-fill composites may simplify posterior restorations, saving time and reducing technical complexity. Post-operative sensitivity is a risk of posterior composites; bulk-fill composites could mitigate this. This single centre, double-blinded, parallel groups randomised controlled trial compared postoperative sensitivity following restoration of class II carious lesions with bulk-fill or conventional, layered composite.

Null hypothesis: there will be no difference in post-operative sensitivity between the two materials.

Methods: Participants requiring class II restoration of posterior teeth were randomised to bulk-fill (FU) (Coltene Fill-UpTM) or conventional, layered (BE) (Coltene Brilliant Everglow) composite. Allocation was concealed during cavity preparation. Only the operating dentist knew allocation. The outcome was 24 h post-operative sensitivity.

Results: 41 patients were randomised (20/group). Two patients from FU group were excluded from analysis (factors unrelated to intervention). There was no difference in postoperative sensitivity at 24 h nor any time point. Only participant age and baseline sensitivity scores significantly impacted post-operative sensitivity. One restoration debonded in FU group at 10 days, with no other adverse effects. No difference in time taken to place restorations was seen.

Conclusions: Within the study's limitations, post-operative sensitivity after class II posterior restorations was no different in bulk-fill restorations compared with conventional, incrementally cured composite.

Objectives: This study aims to compare students' subjective perceptions and objective results by comparing two methods of crown preparation: typodonts and haptics.

Materials and methods: Fifty-four second-year students were given instructions on crown preparation for the upper right second premolar. First on typodonts and then with haptics. They were given five minutes to familiarize with the artificial environment and then thirty minutes for the actual preparation. Finally, they completed a questionnaire about their experience. Their preparations were objectively compared by measuring the angle of total occlusal convergence-TOC on the typodonts and with haptics.

Results: Students reported that haptics can enhance the learning process and that they would use them for skill training in the future. Overall, their experience was rated as positive. The TOC of teeth prepared with haptics was significantly higher than those prepared with typodonts, but all values were within the acceptable range.

Conclusion: Although students did not prefer haptics to typodonts, haptics appear to be a powerful tool in the educational process because it can be a complementary option to traditional methods at the preclinical level.

Introduction: This study aims to investigate the effect of different particle sizes and pressures on the shear bond strength (SBS) and the roughness (Ra) of polyetheretherketone.

Materials and methods: A total of 117 polyetheretherketone specimens were fabricated and divided into a control (CN: no air-particle abrasion) and eight pre-treatment groups (air-abraded with 50- or 110-μm Al2O3 particles at 1(A), 1.5(B), 2(C), and 2.5(D) bar). The adhesive, Visio.link was used. Thermal aging was performed. Surface properties, SBS and failure mode were assessed. Data was analyzed by linear regression, Pearson correlation and Dunnett's T3 test for pairwise comparisons (p⟨0.05).

Results: The highest and lowest Ra were found in the 110D and CN groups respectively, and the highest SBS results were obtained from the 50B group. Pressure and particle size showed significant difference on the investigated properties (p⟨0.001). Only adhesive failure was observed in the CN, and resin cohesive failure was observed in addition to adhesive failure in the overall study groups.

Conclusion: The air-borne particle abrasion procedures and the adhesive material combination are critical to the strength of the polyetheretherketone bond. The combination of visio.link with the pre-treatment option of 50-μm Al₂O₃ particles applied at 1.5-bar pressure delivered the most favorable results.

Aim: Insufficient evidence is available in quantifying the retention between simplified and conventional non-balanced dentures. The aim of the study was to quantify and compare the maxillary denture retention and patient satisfaction between conventional and simplified removable non-balanced complete dentures.

Method: This randomized clinical trial recruited 44 patients (n=22) with definitive criteria. Simplified and conventional non-balanced complete dentures were fabricated for the intervention groups. The denture retention of maxillary complete dentures was assessed with a dynamometer and patient satisfaction with a visual analogue scale. The mean retention of maxillary denture and satisfaction were recorded at 0-,3-, and 6 - month intervals. The data were statistically analyzed. (α=.05).

Results: The mean ±SD of retention for conventional denture at 0, 3, and 6 months by dynamometer ranged from 122 ± 1.64 N to 121 ± 1.57 N and 111 ±1.45N to 110±1.97 N for the simplified denture. The mean ±SD of visual analogue score varied between 9.45±0.35 to 7.19± 0.69 for conventional dentures and 8.00 ±1.39 to 6.81±0.82 for simplified dentures. The repeated ANOVA, t-test and post-hoc Bonferroni revealed statistically significant differences between the two types of denture. (P⟨.05) Conclusion: Numerical retention and satisfaction were higher in conventional non-balanced dentures than simplified dentures.

Introduction: Prosthetic complications that occur to some implant prosthetics may require removal of the prosthesis for replacement or repair. Therefore, the presence of a technique to identify the type of dental implant is mandatory to provide the suitable components. Hence, the aim of the current study was to evaluate the accuracy of YOLOv8 object detection algorithm in automatic identification of the type of dental implant from digital periapical radiographs.

Methods: YOLOv8m-seg object detection algorithm was used to build a model to automatically identify the type of dental implant. A set of 2573 digital periapical radiographs for six distinct dental implants manufacturers were used to train the model. The outcomes were evaluated using precision, recall, F1 score and mAP.

Results: The overall accuracy of the YOLOv8m-seg model in terms of precision, recall, F1 score and mAP revealed values of 0.919, 0.98, 0.95 and 0.972 respectively. The average detection speed of the images was 1.3 seconds. The model was able to detect and identify multiple implants simultaneously on the same image.

Conclusions: YOLOv8m-seg object detection algorithm is promising in identification of dental implants from periapical radiographs with high detection accuracy (97.2%), fast detection results and multi-implant detection from the same image.

Clinical significance: This AI system can accurately identify the type of osseointegrated dental implants enabling dentists to provide the appropriate prosthetic components even if different implant systems are used within the same patient. This can save tremendous amounts of time, effort and cost for both the dentist and the patient.