【摘要】 目的 :比较初萌年轻恒牙和成年恒牙釉质表面组织结构特点并分析这些特点与其釉质抗酸脱矿能力的相关性。方法 :初萌年轻恒牙和成年恒牙标本各 2 8个 ,随机选取每组各 10个标本用于扫描电镜观察釉质表层形态结构 ;每组各 8个标本用显微硬度计测定釉质表层显微硬度值 ;每组各 10个标本用等离子体发射光谱仪测定釉质表层钙磷含量并计算Ca/P比值。结果 :初萌年轻恒牙釉质表面粗糙多孔 ,表层下釉柱排列不紧密 ,存在较多空隙 ,柱间质较宽。初萌年轻恒牙与成年恒牙的釉质表层显微硬度值分别为 345 81± 9 0 9(kg/mm2 )和 36 6 5 8± 19 6 7(kg/mm2 ) ;Ca/P比值分别为 2 0 7± 0 12和 2 18±0 0 7。统计学均有显著性差异 (P <0 0 5 )。结论 :初萌年轻恒牙在釉质矿化程度 ,组织结构上存在明显易患龋齿的因素 ,防龋措施应从牙齿萌出早期开始更多还原

【Abstract】 Objective:To compare the histology of "young" and "old" enamel and to analyze the characteristics of these enamels and their susceptibility to caries.Methods:The surface structure of human enamel was examined in the SEM and microhardness of enamel surveyed.The content of calcium and phosphorus and the ratio of Ca/P were measured.Results: The surface of newly erupted young permanent teeth was rough and porous.Pits and focal holes were obvious.The microhardness of "young" and "old" human enamel was 345 81±9 09 and 366 58±19 67(Kg/mm 2) respectively.The ratios of Ca/P were 2 07±0 12 and 2 18±0 07 respectively.Conclusion: The histological charactoristics of "young" human enamel accounts for the susceptibility to caries.Measures against caries should be taken in the early stage of eruption.更多还原