Narrow Results

It is very important to study the problem of caries and gingivitis in adolescents who are being treated for orthodontic pathology with bracket systems. The method of combined treatment which incorporates the use of medicine and laser therapy has been proved effective in caries prevention. This research aims to study clinical aspects of the effectiveness of the combined influence of the low-intensity laser "OPTODAN" with a wavelength of 0.85 μm (Scientific Development and Production Center "VEND", Saratov, Russia) in caries prevention. The research also aims to study the disinfection method of PAD with "FotoSan" ("CMS Dental", Denmark, with a wavelength of 625–635 nm, where toluidine blue is used as photosensitizer molecules) combined with regular measure to prevent gingivitis in adolescents being treated for orthodontic pathology with bracket systems. This paper presents the results of 1.5 years of clinical study of 60 12–13-year-old children. They were examined before and after the orthodontic treatment: their decayed, missing, filled teeth (DMFT), decayed, missing, filled tooth surfaces (DMFS) index and hygiene status (OHI-S) were calculated, gum inflammations were detected. Before the orthodontic treatment, their mouths were sanitized. After orthodontic appliances were placed, the children were randomly divided into two groups of 30 each. Children of the first group, while being treated with braces, took traditional preventative measures against gum inflammation and caries: occupational hygiene, local antiseptics (0.05% chlorhexidine solution), the use of remineralizing and phosphorus containing applications four times a year. The children of the second group, along with the traditional scheme of preventive measures, were treated with the devices "FotoSan" and "Optodan". Results of clinical examination of the second group have accurately proved decrease in the growth of dental caries intensity and surface caries intensity (ΔDMFT, ΔDMFS) and in gingivitis level at the end of the orthodontic treatment. So the results of our clinical research have proved the effectiveness of laser therapy and comprehensive prevention of caries and gingivitis in adolescents using bracket system.

Prevention is the most effective way to reduce dental caries. In order to provide a simple way to achieve oral healthcare direction in daily life, dual Channel, portable dental Imaging system that combine white light with autofluorescence techniques was established, and then, a group of volunteers were recruited, 7200 tooth pictures of different dental caries stage and dental plaque were taken and collected. In this work, a customized Convolutional Neural Networks (CNNs) have been designed to classify dental image with early stage caries and dental plaque. Eighty percentage ($n=6000$) of the pictures taken were used to supervised training of the CNNs based on the experienced dentists’ advice and the rest 20% ($n=1200$) were used to a test dataset to test the trained CNNs. The accuracy, sensitivity and specificity were calculated to evaluate performance of the CNNs. The accuracy for the early stage caries and dental plaque were 95.3% and 95.9%, respectively. These results shown that the designed image system combined the customized CNNs that could automatically and efficiently find early caries and dental plaque on occlusal, lingual and buccal surfaces. Therefore, this will provide a novel approach to dental caries prevention for everyone in daily life.

The main objective of this study is to evaluate the antibacterial effect of antibacterial photodynamic therapy (aPDT) on Streptococcus mutans (S. mutans) biofilm model in vitro. The selection of photosensitizers is the key step for the efficacy of photodynamic therapy (PDT). However, no studies have been conducted in the oral field to compare the functional characteristics and application effects of PDT mediated by various photosensitizers. In this research, the antibacterial effect of Methylene blue (MB)/650nm laser and Hematoporphyrin monomethyl ether (HMME)/532nm laser on S. mutans biofilm was compared under different energy densities to provide experimental reference for the clinical application of the two PDT. The yield of lactic acid was analyzed by Colony forming unit (CFU) and spectrophotometry, and the complete biofilm activity was measured by Confocal Laser Scanning Microscopy (CLSM) to evaluate the bactericidal effect on each group. Based on the results of CFU, the bacterial colonies formed by 30.4J/cm² 532nm MB-aPDT group and 30.4J/cm² 532nm HMME-aPDT group were significantly less than those in other groups, and the bacterial colonies in HMME-aPDT group were less than those in HMME-aPDT group. Lactic acid production in all treatment groups except the photosensitizer group was statistically lower than that in the normal saline control group. The activity of bacterial plaque biofilm was significantly decreased in the two groups treated with 30.4J/cm² aPDT. Therefore, aPDT suitable for energy measurement can kill S. mutans plaque biofilm, and MB-aPDT is better than HMME-aPDT.