Evaluation of Clinical Students' Perspectives and Satisfaction Levels on Practical Practices at the Faculty of Dentistry of Tokat Gaziosmanpaşa University in the Covid-19 Pandemic

Aim: It was aimed to reveal the perspectives and satisfaction levels of 4th and 5th grade-clinical students who go on practice education at Tokat Gaziosmanpaşa University Faculty of Dentistry in the 2020-2021 Academic Year. Methods: Within the scope of the study, 146 students in total, who did their face-to-face internship between October 5 and December 11, 2020, were asked to participate in an online survey with 10 questions. Clinical students were asked about their perspective on Covid-19 infection, whether they felt safe in their dental practice, their families' level of anxiety about their internship, and whether they voluntarily chose dentistry. Results: According to the survey results; 15.1% of the students agree (TA), 27.4% agree (A), 37% partially agree (PA), 13% disagree (D) with the statement “I am pleased to have internships since the beginning of the term” 7.5% of them answered, “Strongly disagree” (SD). Pearson’s chi-square test was used in the statistical analysis of the answers given by 4th and 5th-grade students to the first 9 questions of the questionnaire consisting of the same questions. According to the survey results, it was also observed that most students chose the dentistry profession of their own will (TA 39%, A 36.3%, PA 13.7%). The number of students who think they feel safe in terms of infection control during their internship is 60% in total (TA 5.5%, A 17.1%, PA 37.7%). Conclusion: Despite the increasing number of cases until today, it is thought that the process has been successfully managed and that the students have gained experience in practical training, albeit limited

Effects of dynamic aging on the wear and fracture strength of monolithic zirconia restorations

Abstract Background The purpose of this study is to evaluate the wear and fracture strength of crowns and three-unit partial fixed dental prosthesis (FDP) fabricated using by Bruxzir and Incoris TZI as recently introduced monolithic zirconia materials. Methods A total of sixteen crowns and sixteen three-unit FDPs were fabricated using Bruxzir and Incoris TZI (n = 8). All specimens were subjected to a 2-body wear test in a dual axis chewing simulator for 1,200,000 loading cycles against steatite antagonist balls. The fracture strength and volumetric loss were recorded. The obtained data were statistically analyzed by 2-way ANOVA testing (α = 0.05). Results The mean volumetric loss of the crowns was higher than that of the three-unit FDPs (p < 0.05). Of the two monolithic systems, Incoris TZI exhibited more wear than Bruxzir. The fracture strengths of Bruxzir crowns and FDPs were found to be higher than those of the crowns and FDPs fabricated with Incoris TZI (p < 0.05). Conclusion In in vitro test conditions, Bruxzir and Incoris TZI monolithic zirconia systems are fracture-resistant for the crown and FDP application against physiologic chewing forces owing to dynamic aging. Among newly developed monolithic zirconia materials, Bruxzir is found to be more resistant to fracture compared to the Incoris TZI

The Effects of Coffee and Energy Drink on Color Stability of Hybrid Ceramics

Purpose: The aim of this study was to compare the color stability of two different hybrid ceramic materials.Materials amp; Methods: Using the precision cutting device (Micracut, Metcon, Turkey), 36 specimens (12 x 15 x 1 mm) were obtained from Vita Enamic (Vita Zahnfabrik, Germany) and Lava Ultimate (3M ESPE, St.Paul, USA) CAD / CAM blocks. After finishing procedures were completed, all specimens were stored in distilled water for 24 h. Then, the specimens were dried and the initial color measurements were made. L, a, b values were determined using a spectrophotometer (Vita Easy Shade, Vita Zahnfabrik, Germany). The specimens were then divided into 3 test groups and stored in coffee (Nescafe Classic, Turkey) (G2, G5), energy drink (Red Bull, Austria) (G3, G6), and in the distilled water as the control group (G1, G4), for 48 h. After 48 h, the specimens were washed with distilled water and dried. Second color measurements were made. ∆E00 values were calculated using the CIEDE 2000 color-difference formula.Results: Data were analyzed by two-way ANOVA. Multiple comparisons were made with Bonferroni’s test. There was a statistically significant difference between 2 ceramics (p=0.035). Generally, Lava Ultimate showed more color change than Vita Enamic. Among the beverages, coffee was significantly different for both ceramics than control and energy drink (p lt;0.05).Conclusion: Lava Ultimate, showed more color change than Vita Enamic. Coffee has also been determined as the most colorant drink for both hybrid ceramics

Evaluation of Shear Bond Strength of Different Resin Cements after Zirconia Surface Treatments

Aim: The aim of the study was to evaluate the shear bond strength (SBS) of different resin cements after zirconia surface treatments Materials and Methods: A total of 60 zirconia discs (3x7mm) were prepared and divided into 3 main groups according to the surface treatments as control (C), sandblasting (SB), and tribochemical silica coating (TC). Main groups were divided into two subgroups according to two different resin cements were applied. No surface treatment was applied to the samples in C group. 50μm Al2O3 particles were applied to the samples in SB group for 10 s at a distance of 10 mm under 4 atm. TC group were tribochemically coated with alumina particles. Self-adhesive resin (ME) and multi-system dual-cure adhesive resin (NX3) was applied to the subgroups. After cementation, all samples were tested for SBS. SBS values were statistically analyzed by the Kruskal-Wallis and Mann-Whitney U tests. Results: Regardless of the cement type, SBS values of the surface treated samples were statistically different (p lt;0.001). Group SB was determined as the group with the highest SBS value. This group was followed by Group C and Group TC, respectively. The SBS values of the samples according to the resin cements and surface treatments were statistically significantly different (p lt;0.001). SBS values of the samples cemented with NX3 resin cement were found to be higher than the samples treated with ME resin cement. Conclusion: SB increased resin bond to zirconia. It is more advantageous to use multi-system dual cure adhesive cements in zirconia cementation

Effect of surface finishing on the colour stability and translucency of dental ceramics

Abstract Background The purpose of this study was to investigate the effects of staining solutions and surface finishing on the colour stability and translucency of hybrid ceramic (HC) and resin nanoceramic (RNC) materials. Methods Twenty four groups consisting of 10 specimens (240 specimens in total) were created out of HC and RNC, including six groups to be stored in distilled water served as the controls groups. The Vita Enamic technical set, Shofu polishers, medium and fine rubber wheels and Sof-Lex polishing discs were used as polishing instruments. Cola, tea, and coffee were used as staining solutions. The colour differences (∆E*) and translucency parameter (TP) were evaluated by a spectrophotometer. Data were analysed by a One-way Analysis of Variance (ANOVA) and Mann-Whitney U test. Results There was a statistically significant difference between the ∆E* values of the HC specimens in the coffee groups and the ∆E* values of the other HC groups (p 0.05). The TP values of the polished groups were higher than the Sof-Lex groups and the Shofu groups on both HC and RNC materials (p < 0.05). Conclusions Increased ∆E* values were observed in HC specimens stored in a coffee solution compared to the specimens stored in a tea or cola solution. Both of the RNC specimens stored in coffee and tea had higher ∆E* values than the RNC specimens stored in the cola. The TP values of both HC and RNC specimens stored in the coffee solution decreased

Assessment/Evaluation of Dentistry Students' Perceptions of Distance Learning During the Covid-19 Pandemic Process: A Two Centers Study

Purpose: The present study aimed to comparatively evaluate the acceptance perceptions of satisfaction towards distance theoretical education of students studying at Tokat Gaziosmanpaşa University faculty of dentistry (new faculty), which is newly established and located in the countryside, and Ankara University faculty of dentistry (old faculty) located in a metropolitan, during the Covid-19 pandemic. Materials Methods: For this cross-sectional study, a questionnaire consisting of 5 parts and compatible with a Likert scale was prepared. The prepared questionnaire was sent online to the 3rd, 4th, and 5th-grade students at the end of the 2020-2021 academic year. Pearson chi-square analysis was applied to determine the difference between qualitative variables according to the groups. The appropriate chi-square test was used for comparison of categorical variables between groups. The statistical significance level was determined as

The effect of the different restorations on fracture resistance of root-filled premolars

Abstract Background The study investigated the fracture resistance of root-filled maxillary premolars with class II cavities restored by different restorations. Methods A total of 55 intact maxillary premolar teeth were included (n = 11). G1 as positive control group, 44 teeth underwent root canal treatment, and MOD cavities were prepared. (G2) no restoration, (G3) direct composite restoration, (G4) direct composite strengthened with buccal to lingual pre-impregnated glass-fibers and (G5) ceramic inlay restoration. After thermocycling, fracture resistance test was performed and fracture type was recorded. Data were analyzed with one-way ANOVA and Chisquare test. Results The mean fracture resistance was as follows: G1 had the highest fracture resistance, G2 had the lowest (p  0.05). According to fracture type, the groups showed similar results (p > 0.05). A significant level of unrestorable fracture was detected in G5 (ceramic inlay) (p < 0.05). Conclusions All of the restoration techniques investigated herein increased the fracture strength of teeth; however, all of these values were lower than the fracture resistance of intact teeth. There were no significant differences between the fracture resistance values of the groups that underwent different restorations

Genotyping via Sequence Related Amplified Polymorphism Markers in Fusarium culmorum

Fusarium culmorum is predominating causal agent of head blight (HB) and root rot (RR) in cereals worldwide. Since F. culmorum has a great level of genetic diversity and the parasexual stage is assumed for this phytopathogen, characterization of isolates from different regions is significant step in food safety and controlling the HB. In this study, it was aimed to characterize totally 37 F. culmorum isolates from Turkey via sequence related amplified polymorphism (SRAP) marker based genotyping. MAT-1/MAT-2 type assay was also used in order to reveal intraspecific variation in F. culmorum. MAT-1 and MAT-2 specific primer pairs for mating assays resulted in 210 and 260 bp bands, respectively. 11 of isolates were belonged to MAT-1 type whereas 19 samples were of MAT-2. Remaining 7 samples yielded both amplicons. Totally 9 SRAP primer sets yielded amplicons from all isolates. Genetic similarity values were ranged from 39 to 94.7%. Total band number was 127 and PCR product sizes were in the range of 0.1-2.5 kb. Amplicon numbers for individuals were ranged from 1 to 16. According to data obtained from current study, SRAP based genotyping is powerful tool for supporting the data obtained from investigations including phenotypic and agro-ecological characteristics. Findings showed that SRAP-based markers could be useful in F. culmorum characterization