第一恒磨牙龋预测相关因素的纵向研究

Dental caries prediction: a two-year longitudinal study of caries in occlusal fissures of first permanent molars

目的 探讨乳牙龋状态与恒牙新发龋的内在联系 ,并尝试建立预测第一恒磨牙新发龋个体的多因素回归模型 ,筛查有意义的龋微生物预测指标。方法 12 6名 6～ 8岁儿童 ,其中乳牙有龋 6 2名 (CS组 )、乳恒牙均无龋者 6 4名 (CF组 ) ,进行口腔检查和问卷调查并采集菌斑样本检测 :①变形链球菌、乳酸杆菌水平 ;②耐酸菌水平 ;③产乳酸能力。对所得二年纵向资料进行常规统计分析和以恒牙新增龋二分变量为结果变量、各微生物指标为自变量的二值逻辑回归分析。结果 混合牙列初期第一恒磨牙窝沟菌斑总菌计数值、在酸性条件下的产乳酸能力以及全口光滑面集合菌斑中耐酸菌数量是个体恒牙新发龋预测的危险性指标 ,其显著性超过乳牙既往龋经历。结论 提高观察指标位点特异性有助于提高龋预测能力。

Objective To study caries incidence i n permanent teeth in relation to microbiologic parameters and past caries experien ce in primary dentition.Methods One hundred and twenty-six 6 to 8 year-old school children were selected from two primary schools in Beijing;64 caries free (CF), 62 caries susceptible (CS, dmft ≥ 2 and DMFT = 0).Oral and dental examinations were performed at baseline, one and two years after,respectively.At the same tim e, plaque samples were separately collected from occlusal surfaces of first perm anent molars and smooth surfaces of the whole dentition.Numbers of total cultiva ble microflora,mutans streptococci and lactobacilli were determined by standard microbiological techniques.Predominant aciduric bacteria were determined with t he MPN technique.Lactate-producing ability of plaque samples at pH 7.0 and pH 5. 2 was also determined.All variables were tested by common statistic analysis and stepwise multiple logistic regression analysis to determine the most significan t parameters related to the new caries.Results and Conclusion ①The most significant risk factor s with predictive power for first permanent molars were:count of total cultivabl e microflora (logarithm transferred),lactate acid produced by dental plaque at p H5.2 and aciduric bacteria level in pooled dental plaque.These predictors were s tronger than past caries experience in deciduous teeth.Predictive power of site- specific factors improved significantly.②The predictive power of the models was encouraging.It suggested that to search for a practical risk-assessment model that can be applied to an individual patient is worthy continuing.