CBCT评价下颌第一恒磨牙牙冠硬组织厚度增龄性变化

CBCT evaluation of aging changes of dental crown's hard tissue thickness in mandibular first permanent molar

目的 利用锥形束CT（CBCT）测量下颌第一恒磨牙牙冠硬组织厚度的增龄性变化。方法 收集本院645例患者的下颌第一恒磨牙CBCT资料,分为6~15岁、〉15~25岁、〉25~35岁、〉35~45岁、〉45~55岁、〉55~65岁、〉65~82岁7个年龄段,测量牙釉质、牙本质、髓腔高度、髓底、近中髓角上方牙冠硬组织、远中髓角上方牙冠硬组织的厚度。结果 各年龄段的远中髓角上方牙冠硬组织厚度的变化差异无统计学意义（P〉0.05）,其余牙冠硬组织厚度的增龄性变化差异均有统计学意义（P均〈0.05）。结论 下颌第一恒磨牙牙冠硬组织的牙釉质厚度、牙本质厚度、髓腔高度、髓底厚度和近中髓角上方牙冠硬组织厚度存在明显的增龄性变化,在远中髓角上方牙冠硬组织厚度无明显的增龄性变化。

Objective To measure the aging changes of mandibular first permanent molar about the dental crown＇s hard tissue thickness with cone beam computed tomography （CBCT）. Methods CBCT dates of mandibular first permanent mo- lar of 645 patients were enrolled. Data were divided into seven groups： 6--15 years old, 〉15-25 years old, 〉25-35 years old, 〉35-45 years old, 〉45-55 years old, 〉55-65 years old, 〉65-82 years old. The tissue thickness of enamel, dentin, pulp cavity, floor of pulp chamber, mesial pulp horn above, distal pulp horn above were measured. Results The aging changes of distal pulp horn above were not statistically significant in different aging groups （P〉0.05）, the others were statistically significant （all P〈0.05）. Conclusion The mandibular first permanent molar about the hard tissue thickness of enamel, dentin, pulp cavity, floor of pulp chamber, mesial pulp horn above exist has obvious aging changes, while there is no obvious aging changes in distal pulp horn.