Abstract：Objective To study the association of primary teeth caries with caries of the first permanent molar. Methods A cluster random sampling method was used to select first-grade pupils aged 7 years in three primary schools in urban areas of Zhuhai City for teeth caries examination in November 2016.Pupils with caries of primary teeth were defined as the exposure group, whereas ones without caries of primary teeth served as the control group. Retrospective cohort study was conducted to compare the prevalence rates of caries of the first permanent molar between the two groups.The association between the number of caries of the first permanent molar and the number of primary teeth caries was analyzed. And the prevalence rates of caries of the first permanent molar in different eruption stages were compared. Results The eruption rate of the first permanent molars in the pupils aged 7 years from the three primary schools was 92.5%. The prevalence rate of caries of the first permanent molar and the average decayed, missing and filled teeth (DMFT) were 13.5% and (1.99±1.06) respectively. The prevalence rate of primary teeth caries and the average decayed, missing and filled teeth (DMFT) were 61.93% and (4.35±2.67) respectively. The prevalence rates of caries of the first permanent molar and primary teeth caries were both higher in girls than in boys (18.54% vs. 9.06%, χ2=11.453, P=0.001; 66.67% vs. 57.87%, χ2=5.68, P=0.017). Retrospective cohort study showed that the relative risk (RR) of caries of the first permanent molar in the primary teeth caries group was 3.18(95%CI:1.84-5.51)as compared with the control group. The RR in girls was 4.15(95%CI:1.84-9.36). Among boys, the prevalence rate of caries of the first permanent molar showed no statistically significant difference between the primary teeth caries group and the control group (P>0.05). The number of caries of the first permanent molar was positively correlated with the number of primary teeth caries (r=0.308, P=0.003). The prevalence rate of caries of the first permanent molar was found to be the highest at first eruption stage(44.4%). Conclusions Dental caries in primary teeth of children aged 7 years is a risk factor of caries of the first permanent molar. Preventive measures should be taken when the first permanent molar is erupted.
李晓茹, 杨烨, 黄丰, 杨燕. 7岁儿童乳牙龋齿对第一恒磨牙患龋的影响[J]. 实用预防医学, 2018, 25(6): 688-690.
LI Xiao-ru, YANG Ye, HUANG Feng, YANG Yan. Association of primary teeth caries with caries of the first permanent molar among children aged 7 years. , 2018, 25(6): 688-690.
2018, Vol. 25 
