Department of Pediatric Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, São Paulo, Brazil.
Department of Restorative Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Avenida do Café, Ribeirão Preto, São Paulo, S/N, 14040-904, Brazil.
Lasers Med Sci. 2023 Sep 12;38(1):208. doi: 10.1007/s10103-023-03869-0.
This study evaluated the effect of chitosan on dentin treatment after selective removal of caries lesions with Er:YAG laser in reducing Streptococcus mutans, as well as its effect on the performed restorations. The sample consisted of children (aged 7 to 9 years) with active carious lesions and dentin cavitation located on the occlusal surface of deciduous molars. Eighty teeth were randomly distributed into 4 groups according to the caries removal method: Er:YAG laser (250 mJ/4 Hz) or bur and dentin surface treatment: 2.5% chitosan solution or distilled water. The bacterial load of caries-affected dentin was quantified by counting CFU/mg (n = 10). The teeth were restored and evaluated at 7 days, 6 months, and 12 months using modified USPHS criteria (n = 20). Microbiological data was analyzed by Mann-Whitney and clinical analyses were done using Kruskal-Wallis and Dunn test (α = 0.05). The results showed that the Er:YAG laser significantly reduced the amount of Streptococcus mutans (p = 0.0068). After dentin treatment with chitosan, there was a significant reduction in the amount of Streptococcus mutans for both removal methods (p = 0.0424). For the retention and secondary caries criteria, no significant differences were observed along the evaluated time (p > 0.05). The laser-treated group was rated "bravo" for discoloration (p = 0.0089) and marginal adaptation (p = 0.0003) after 6 and 12 months compared to baseline. The Er:YAG laser reduced the amount of Streptococcus mutans and the chitosan showed an additional antibacterial effect. After 1 year, the Er:YAG laser-prepared teeth, regardless of the dentin treatment, showed greater discoloration and marginal adaptation of the restorations.
本研究评估了壳聚糖在 Er:YAG 激光选择性去除龋损后处理牙本质以减少变形链球菌的效果，以及其对所进行修复的影响。样本包括患有活跃龋损和位于乳磨牙咬合面牙本质空洞的 7 至 9 岁儿童。根据龋损去除方法将 80 颗牙齿随机分为 4 组：Er:YAG 激光（250 mJ/4 Hz）或车针和牙本质表面处理：2.5%壳聚糖溶液或蒸馏水。通过 CFU/mg 计数量化受龋损影响的牙本质的细菌负荷（n=10）。用改良的 USPHS 标准在 7 天、6 个月和 12 个月时对牙齿进行修复和评估（n=20）。用 Mann-Whitney 分析微生物数据，用 Kruskal-Wallis 和 Dunn 检验进行临床分析（α=0.05）。结果表明，Er:YAG 激光显著降低变形链球菌的数量（p=0.0068）。在用壳聚糖处理牙本质后，两种去除方法的变形链球菌数量均显著减少（p=0.0424）。在保留和继发龋标准方面，在评估期间未观察到显著差异（p>0.05）。与基线相比，激光处理组在 6 个月和 12 个月时的着色（p=0.0089）和边缘适应性（p=0.0003）方面被评为“优秀”。与基线相比，Er:YAG 激光减少了变形链球菌的数量，壳聚糖表现出额外的抗菌作用。1 年后，无论牙本质处理如何，用 Er:YAG 激光制备的牙齿的修复体都显示出更大的着色和边缘适应性变化。
