Lula E C O, Monteiro-Neto V, Alves C M C, Ribeiro C C C
Graduate Program in Health Sciences, College of Dentistry, Federal University of Maranhão, São Luís, Brazil.
Caries Res. 2009;43(5):354-8. doi: 10.1159/000231572. Epub 2009 Aug 1.
Since viable bacteria can persist in tooth cavities regardless of the technique used for caries removal, the objective of the present randomized clinical trial was to examine the microflora of primary teeth treated by complete or partial removal of carious dentin. Deciduous molars with acute carious lesions in the inner half of dentin and vital pulp were randomly divided into two groups of 16: complete removal, in which the carious dentin was completely removed with the help of a caries detector dye, and partial removal, in which the carious dentin was completely removed from the dentinoenamel junction and lateral walls, while the necrotic carious dentin from the cavity floor was only removed superficially. Dentin samples were obtained with a sterile No. 3 bur after caries removal and 3-6 months after protection with calcium hydroxide cement and restoration of the cavities with resin composite. The samples were stored in thioglycolate. Decimal dilutions were then prepared and seeded for the enumeration of Streptococcus spp., mutans streptococci, Lactobacillus spp. and total microorganisms. Before sealing, a larger number of microorganisms was detected in teeth submitted to partial caries removal compared to the complete removal group. However, after sealing the level of colonization was similar in the two groups for all microorganisms studied. The results suggest that persistence of bacteria does not seem to be a reason for reopening of cavities in deciduous teeth after partial caries removal.
由于无论采用何种龋齿去除技术，活细菌都可能在龋洞中持续存在，因此本随机临床试验的目的是检查通过完全或部分去除龋坏牙本质治疗的乳牙的微生物群。牙本质内层有急性龋损且牙髓活力正常的乳磨牙被随机分为两组，每组16颗：完全去除组，即借助龋病检测染料将龋坏牙本质完全去除；部分去除组，即从牙釉质牙本质界和侧壁完全去除龋坏牙本质，而仅浅层去除髓腔底部的坏死龋坏牙本质。在去除龋坏组织后，以及在用氢氧化钙粘固剂保护并使用树脂复合材料修复龋洞3 - 6个月后，用无菌的3号钻获取牙本质样本。样本保存在硫代乙醇酸盐中。然后制备十进制稀释液并接种，以计数链球菌属、变形链球菌、乳酸杆菌属和总微生物。在封闭之前，与完全去除组相比，部分龋坏去除的牙齿中检测到的微生物数量更多。然而，在封闭后，两组中所有研究的微生物的定植水平相似。结果表明，细菌的持续存在似乎不是部分龋坏去除后乳牙龋洞重新开放的原因。
