Rosenbenton3586

Finite element analyses were performed under physiologic masticatory forces with axial and oblique loading vectors. Results. After simulation of axial loads, the stress peaks on the bone around the implant, the bone around the first premolar, and prosthetic structures did not exhibit significant changes when the number of abutment teeth decreased. However, under oblique loads, decreasing the number of abutment teeth increased stress peaks on the surrounding bone and denture. Conclusion. Increasing the number of dental abutments in tooth‒implant-supported cemented FPD models decreased stresses on its constituents, favoring the prosthetic biomechanics.Background. Dental caries is the most important reason for tooth loss. Clinical examination is the most commonly used technique for occlusal caries diagnosis. The diagnostic power of digital systems is a matter of controversy in this field. The present study aimed to determine the diagnostic accuracy of two photostimulable phosphor plate (PSP) systems for early occlusal dentin caries in vitro. Methods. Sixty-nine extracted molar and premolar teeth were used in this study. The teeth were mounted in triple blocks, and standard radiographs were taken by the Digora and Acteon digital radiographic systems. The original and filter 1-enhanced radiographs were evaluated by two experienced observers twice at an interval of two weeks, and dentin caries was recorded in Tables prepared for the study. The teeth were then sectioned in a buccolingual direction and evaluated under a stereomicroscope. The observers' reports were compared with microscopic findings as the gold standard. SPSS 23 was used to calculate the kappa coefficient, sensitivity, specificity, and area under the ROC curve (AUC). Selleck ML-7 Statistical significance was set at P less then 0.05. Results. The internal and the external agreements in both imaging systems were good to excellent. The means of sensitivity, specificity, and AUC in the Acteon system were 34.1, 92.9, and 0.674, with 30.8, 94.8, and 0.659, respectively, in the Digora system. Conclusion. The accuracy of early occlusal caries diagnosis was poor on both systems, and no significant difference was observed between the two systems at a 95% confidence interval. Although the AUC was slightly higher in the original images, there was no significant difference between them; however, due to their high specificity, they can prevent unnecessary treatments in the clinic.Background. Designing a high strength all-ceramic fixed partial denture with favorable esthetics can be challenging for clinicians; this study aimed to evaluate the effect of connector size and design on the fracture resistance of monolithic zirconia fixed dental prostheses. Methods. Two groups of twenty 3-unit monolithic zirconia (Sirona inCoris TZI, Sirona Dental Systems GmbH) bridges, extending from the mandibular first premolar to the first molar with different connector sizes (9 mm2 and 12 mm2), were divided into two subgroups with different connector designs (round and sharp). The specimens were subjected to the three-point bending test to obtain the fracture-bearing load. The results were reported using descriptive statistics (mean ± standard deviation). Mann-Whitney U test was used to compare the fracture load in two types of designs for each connector size and two connector size types for each connector design. The significance level was considered at P less then 0.05. Results. The minimum failure load was related to the group with a 9-mm2 connector size and a sharp embrasure design (1054.4±133.89 N), and the highest mean value belonged to the group with 12-mm2 connector size and rounded embrasure design (1599.8±167.09 N). Mann-Whitney U test indicated a significant difference between the mean failure load of the rounded and sharp embrasure designs in the 9-mm2 connector size (P =0.007). However, the difference was insignificant in the 12-mm2 connector size (P =0.075). Conclusion. Sharp embrasure design is not recommended for high-stress areas with restricted occlusogingival height. A 9-mm2 connector size for 3-unit monolithic zirconia fixed dental prosthesis (FDP), which is recommended by the manufacturer, should be used more cautiously.Background. The present in vitro study aimed to compare the effectiveness of the WaveOne and ProTaper Gold systems in removing the Enterococcus faecalis biofilm. Methods. Thirty-eight mandibular premolars were selected. The root canals were assigned to standard control (canals serially enlarged with ProTaper Gold S1-S2-F1-F2, n=15) and experimental (canals enlarged with Primary WaveOne file, n=15) groups. Following the instrumentation procedure, the root canals underwent a sampling procedure, and the colonyforming unit (CFU) counts were determined. The samples were also evaluated under a fluorescent microscope to evaluate viable bacteria. The data were analyzed using independent samples t test and paired samples t test. Results. The results showed that, compared with the ProTaper group, the WaveOne group exhibited the least viable bacteria (P =0.004). Conclusion. It was concluded that comparison with the ProTaper Gold rotary system, the WaveOne reciprocating file is more successful in reducing intratubular viable bacteria counts.Background. A correlation has been noted between diabetes mellitus (DM) and changes in the oral cavity. The present study aimed to estimate, compare, and correlate serum and salivary glucose and IgA levels and salivary candidal carriage in diabetic and non-diabetic individuals. Methods. Eighty-eight subjects were categorized into three groups group 1 (controlled DM; n=27), group 2 (uncontrolled DM; n=32) and group 3 (non-diabetics; n=29). Serum and salivary glucose levels were estimated by glucose oxidase/peroxidase method, serum and salivary IgA by a diagnostic kit, and candidal colonization by inoculating samples into Sabouraud dextrose agar plate. Statistical analyses were carried out by one-way ANOVA, post hoc Tukey tests, and Pearson's correlation coefficient. Results. Significant elevation of serum IgA levels was observed in group 2 compared to group 3 and significant decreases in salivary IgA levels in groups 1 and 2. The candidal carriage was significantly higher in group 2 compared to group 3. Serum glucose and salivary IgA levels showed a significant correlation in group 1.