In Vitro Assessment of Long-Term Fluoride Ion Release from Nanofluorapatite.

The issue concerning the tooth decay is ongoing, therefore the study of materials with potential use in its prevention is crucial. This study aimed to analyze the long-term release of fluoride from synthesized nanofluorapatite in various in vitro environments for its potential use in dental materials. We placed 100 mg samples in 0.9% NaCl or deionized water and incubated them at 37 °C or 22 °C for 12 weeks. F- levels were read at 1, 3, 24, 48, 72, and 96 h, and thereafter weekly. The levels of F- released at specific time intervals, as well as their cumulative values were compared. In a solution of 0.9% NaCl at 22 °C, there were no significant differences in the amount of F- released in the assessed time intervals, while at 37 °C, the highest value was read after 24 h (0.0697 ppm + 0.0006; p < 0.05). In deionized water, the highest amount of F- at 22 °C was read after 4 weeks (0.0776 ppm + 0.0028; p < 0.05), and at 37 °C, it was also the highest after 4 weeks (0.0910 ppm + 0.0156; p < 0.05). Under the same conditions, after 5 weeks the cumulative level of F- released (0.6216 ppm + 0.0085) significantly increased (p < 0.05), when compared to the samples placed in 0.9% NaCl at 37 °C and 22 °C (0.5493 ppm + 0.0321 and 0.5376 ppm + 0.0234, respectively). FAp releases F- for a long period of time in all assessed environments, therefore it is advised to continue testing in vivo models. Due to the probable remineralization effect towards hard tooth tissues, fluorapatite can be used in the prevention and treatment of dental caries and dentin hypersensitivity.

Assessment of Heat Hazard during the Polymerization of Selected Light-Sensitive Dental Materials.

Introduction. Polymerization of light-cured dental materials used for restoration of hard tooth tissue may lead to an increase in temperature that may have negative consequence for pulp vitality. Aim. The aim of this study was to determine maximum temperatures reached during the polymerization of selected dental materials, as well as the time that is needed for samples of sizes similar to those used in clinical practice to reach these temperatures. Materials and Methods. The study involved four composite restorative materials, one lining material and a dentine bonding agent. The polymerization was conducted with the use of a diode light-curing unit. The measurements of the external surface temperature of the samples were carried out using the Thermovision®550 thermal camera. Results. The examined materials significantly differed in terms of the maximum temperatures values they reached, as well as the time required for reaching the temperatures. A statistically significant positive correlation of the maximum temperature and the sample weight was observed. Conclusions. In clinical practice, it is crucial to bear in mind the risk of thermal damage involved in the application of light-cured materials. It can be reduced by using thin increments of composite materials.

Assessment of the influence of vegetarian diet on the occurrence of erosive and abrasive cavities in hard tooth tissues.

INTRODUCTION: The aim of the study was to determine the potential relation between vegetarian diet and tooth erosion and abrasion. MATERIAL/METHODS: The examination included 46 vegetarians and the same number in the control group. Clinical research was carried out in order to detect the presence of abrasive and erosive changes and the level of hygiene in oral cavities. The questionnaire survey concerned dietary and hygienic habits. Statistical analysis of the data was conducted with Chi-square test and Mann-Whitney U test. The relations between following a vegetarian diet and the occurrence of non-carious cavities was tested with models of logistic regression. RESULTS: Tooth erosion was present among 39.1% of vegetarians and 23.9% of controls, while abrasion appeared among 26.1% and 10.9%, respectively, and the differences were statistically insignificant. The distribution of the changes was similar in both groups. Among vegetarians, significantly more frequent consumption of sour products (predominantly raw vegetables and fruit and tomatoes) was observed. The level of oral hygiene and hygienic habits were similar in both groups. The analysis of statistical regression did not reveal any relations between following a vegetarian diet and the occurrence of tooth erosion and abrasion. DISCUSSION: The results did not reveal any direct influence of vegetarian diet on the occurrence of erosive and abrasive changes. However, in the vegetarian group, more frequent consumption of some sour products and more commonly used horizontal brushing method were observed, with a slightly higher occurrence of non-carious cavities. Further research is required to obtain unambiguous conclusions.