Objective. The causes of internal posteruptive discoloration of teeth are bleeding, necroses, infections, and endodontic filling materials. The aim of this study was to establish the results of bleaching endodontically treated teeth using walking bleach, in-office, and combined techniques, using 30% carbamide peroxide and 35% hydrogen peroxide, as well as the effect of etiological factors, and the time elapsed after endodontic treatment on the success of bleaching. Materials and Methods. The research involved 30 endodontically treated teeth in healthy patients. Retroalveolar X-rays were taken to check the quality of root canal obturation. Endodontic treatment and obturation were carried out on the discolored non-vital teeth without any previous endodontic treatment. Before bleaching, two millimeters of the filling were removed from the root canal and the very entry into the canal was protected with glass ionomer cement. The teeth were divided into three groups, depending on the bleaching technique: walking bleach technique (10 patients), in-office technique (10 patients), and combined technique (10 patients). The teeth were bleached with 30% carbamide peroxide and 35% hydrogen peroxide. The bleaching procedure was repeated in all the patients three times. The color of all teeth was determined based on the Vita Classic guide before and after bleaching. The Χ² square and Kruskal–Wallis tests were used to identify differences in teeth bleaching results. Results. A statistically significant difference (p < 0.05) was established between bleaching success and the time elapsed after endodontic treatment. There were no statistically significant differences observed between the bleaching success and etiological factors, bleaching techniques, or bleaching agents. Conclusions. The effectiveness of non-vital tooth bleaching is affected by the time elapsed after endodontic treatment.

Introduction. Marginal seal or adequate marginal adaptation of material along the cavity walls should be able to prevent leakage of tissue fluid and consequently bacterial microleakage, terefore, it is considered as significant factor for long term success of endodontic treatment. The aim of this work was to test the marginal microleakage of newly synthesized nanostructured biomaterials based on calcium aluminate, calcium silicate and MTA with a dye penetration test after application the material to the interradicular perforations of extracted teeth. Material and method. The study included 48 extracted human maxillary and mandibular molars. Newly synthesized nanostructured materials were tested: material based on calcium aluminate, calcium silicate. Commercial calcium silicate cement (MTA Angelus, Londrina, Brazil) was used as a control material. Marginal microleakage was examined with a dye penetration test six months after application of the material in experimentally prepared interradicular perforations on extracted human molars. Penetration depth measurement was analyzed with a binocular magnifier (Leica DM 500, Leica Byosistems). Results are expressed in millimeters and statistically processed by applying the analysis of variance for repeated measurements with the Sidak test. Results. The lowest average penetration (mm) was for MTA (1.40 ? 0.63 mm), and the highest for Ca aluminates (2.10 ? 0.63 mm), while for calcium silicates an average color penetration of 1.73 ? 0, 67mm was recorded. By testing intergroup differences in color penetration between groups, a statistically significant difference between MTA and Ca aluminate was obtained using Sidak?s test (t = -0.693; p = 0.036). No statistically significant difference was recorded between MTA and Ca silicate, nor was there a statistically significant difference between Ca aluminate and Ca silicate. Conclusion. The lowest marginal microleakage, the best marginal sealing, was recorded with the MTA material. The microleakage of calcium aluminate-based materials was significantly higher compared to calcium silicate and MTA.

Introduction: Fixed orthodontic therapy is often accompanied by accumulation of plaque around the orthodontic brackets, which increases the number of periodontopathogenic bacteria.

The primary objective of this research was to evaluate the oral health habits, dietary practices, and knowledge regarding cariogenic diet among University Dental students. Materials and methods: A cross-sectional, questionnaire-based study was conducted among students attending the integrated undergraduate and graduate Dental Medicine (DM) program. Data analysis was performed by stratifying students according to the year of study. In total, 114 questionnaires were collected. Three questionnaires were subsequently excluded, resulting in a final sample size of 111 students for analysis. Results: Over 75% of students from the 2nd (83.3%) to 6th (91.3%) year used a combination of a toothbrush and fluoride toothpaste, whereas 50% of 1st-year students reported using fluoride-free toothpaste (p < 0.05). The majority of senior students (34.8–100%) correctly identified xylitol and sorbitol as non-cariogenic (p < 0.05). However, a notable knowledge gap persisted in the final year, with over 30% of sixth-year students failing to identify them. Furthermore, over 60.0% of third-year and 90.0% of fifth-year students recognized the protective dental effects of hard cheese, cranberry, and green tea (p < 0.05). Regarding cariogenic potential, 45.8% of first-year and 57.1% of second-year students were unable to identify the most cariogenic saccharide (p < 0.05). Conclusions: The study reveals an improvement in oral health habits and knowledge, particularly regarding the use of fluoride toothpaste and the identification of cariogenic saccharides. However, significant knowledge gaps persist across all years, most notably the high prevalence of fluoride-free toothpaste use among first-year students and the inability of a substantial portion of senior students to identify non-cariogenic sugar substitutes and protective foods.