Study on the prevalence of root caries and the effects of pH value and calcium and phosphorus ion concentra-tion of gingival crevicular fluid on it in type 2 diabetes mellitus patients

JIA Lu-yao; LI YA-jing; YAN Lu

doi:10.19538/j.kq.2024.06.007

Abstract：Objective To study the prevalence of root caries in type 2 diabetes mellitus(T2DM)and the effects of gingi-val crevicular fluid(GCF)pH and calcium and phosphorus ion concentration on it,thus to provide new ideas for the pre-vention and risk assessment of root caries.Methods From April 2023 to January 2024,1625 healthy subjects and 706 T2DM subjects were recruited for screening for root caries in the Endodontic Disease department of the Stomatologi-cal Hospital of China Medical University,and the inci-dence of root caries,the mean caries,the nature of root caries,the prevalence of root caries and the severity were analyzed.Among the recruited subjects,151 subjects volunteered to participate in the questionnaire survey and further oral examination,including 62 healthy subjects and 89 T2DM subjects,and we analyse the influencing factors of the root caries.Among the subjects who completed questionnaire survey and oral examination,60 subjects who met the inclusion criteria were randomly selected,and their GCF was collected and pH,calcium ion concentration and phosphate concen-tration determined,including 24 healthy subjects(control group)and 36 T2DM subjects(T2DM group),and they were di-vided into caries group and no caries group.Results ① A total of 2331 subjects had a root caries rate of 4.46％(104/2331);among them,the incidence of root caries in healthy subjects was 2.40％(39/1625),which was significantly lower than that in T2DM subjects[9.21％(65/706)],and the difference was statistically significant(x2=53.497,P＜0.001).In subjects with root caries,the mean caries and nature had no statistical difference between healthy subjects and T2DM subjects(all P＞0.05);T2DM subjects were more likely to have grade Ⅰ root caries,and those with well-controlled glu-cose were more likely to be grade Ⅰ root caries than those with poor-controlled glucose(all P＜0.05).②Analysis of fac-tors affecting root caries in 151 subjects showed that frequency of tooth brushing(≥ 3 times/d)(OR=0.376,95％CI:0.211-0.669,P＜0.001)and number of annual visits to the stomatology department(＞1-4 times)(OR=0.282,95％CI:0.131-0.607,P＜0.001)were protective factors for root caries;further analysis found that root caries in T2DM subjects was not related to the length of having T2DM,complications or glycemic control,and the difference was not statistically significant(all P＞0.05).③The GCF pH value and calcium ion concentration of T2DM group were lower than those of control group,the GCF pH value of caries group was lower than that of no caries group,and the phosphate concentration was higher than that of no caries group,the differences being statistically significant(all P＜0.05).Analysis of the four subgroups showed that compared to the subgroup without caries in the control group,the pH and calcium ion concentra-tion decreased and the phosphate concentration increased in the subgroup with caries in T2DM group;moreover,the pH value of the subgroup with caries of T2DM group was only lower than that of the subgroup without caries of T2DM group;all the differences were statistically significant(all P＜0.05).Conclusion Increasing the frequency of tooth brushing and the number of annual dental visits may reduce the risk of root caries in T2DM patients,and the lower GCF pH in T2DM patients may be related to the higher incidence of root caries.