儿童上颌第一乳磨牙牙冠增龄性变化的初步研究

A preliminary study on age-related changes in the crown of the first maxillary molar in children

目的测量不同年龄组儿童上颌第一乳磨牙的解剖参数,评估牙冠增龄性变化。方法回顾性分析评估了154例4~8岁儿童患者308颗上颌第一乳磨牙的锥形束计算机断层扫描(CBCT)图像。用NNT软件分析上颌第一乳磨牙的多个重要指标。结果髓顶厚度H1(左侧,P=0.01;右侧,P=0.02)和髓室底厚度H3(左右侧P<0.01)与年龄呈正相关,而髓腔高度H2(左右侧P<0.01)和腭尖的高度D1(左侧P=0.003,右侧P=0.002)与年龄呈负相关。颊尖的高度与年龄无关。4、5岁年龄组与8岁年龄组之间的H1和H3差异有统计学意义(P<0.05),4、5岁年龄组与6、7岁和8岁年龄组之间的H2和D1差异有统计学意义(P<0.05)。结论上颌第一乳磨牙牙冠的年龄相关性变化是临床治疗的重要参考依据,可以通过CBCT数据进行精确测量。

Objective To measure the anatomical parameters of the first maxillary molars in children of different age groups and evaluate the age-related changes in dental crowns.Methods A retrospective analysis was conducted on cone beam computed tomography(CBCT)images of 4-8-year-old children.NNT software was used to analyze multiple important indicators of maxillary first molar.Results A total of 308 first maxillary molars,including 154 pediatric patients,were evaluated in this study.The thickness of the pulp apex H1(left,P=0.01;right,P=0.02)and the thickness of the pulp chamber floor H3(left and right P<0.01)were positively correlated with age,while the height of the pulp cavity H2(left and right P<0.01)and the height of the palate tip D1(left P=0.003,right P=0.002)showed a negative correlation with age.There was no significant correlation between the height of the buccal tip and age(P>0.05).There were significant differences in H1 and H3 between the 4-year-old and 5-year-old age groups between the 8-year-old age group(P<0.05),as well as significant differences in H2 and D1 between the 4-year-old and 5-year-old between the 6-year-old,7-year-old and 8-year-old age groups(P<0.05).Conclusion The age-related changes in the crowns of the first maxillary molars are important references for the clinical treatment,and can be accurately measured through CBCT data.