摘要
【目的】分析上颌骨内埋伏正中多生牙的生长特征与影像学特点,探讨其早期诊断与术前三维定位的方法。【方法】对216例上颌骨埋伏正中多生牙患者进行系统的临床检查与X线定位摄影,对埋伏正中牙的生长特征(方向、类型、形态、大小),影像定位诊断及其对邻近恒牙的干扰情况分类统计分析。【结果】该类多生牙最常表现为圆锥型小牙,平均长度为1.6cm,平均直径为0.6cm;其在上颌骨内常呈倒置向(83.5%),并居于恒中切牙的腭侧为主(76.5%)。对邻近切牙的干扰主要为造成恒中切牙的间隙过大(36.6%)、扭转移位(33.3%)和萌出受阻(19.9%)。位于恒牙根侧方的多生牙对中切牙生长的干扰远大于恒牙根上方的多生牙(P<0.01)。【结论】上颌骨埋伏正中牙多为圆锥型小牙,常紧贴于恒中切牙的腭侧或近中倒置生长,其对中切牙的生长干扰较大;用X线视差定位法可作出准确的三维定位诊断,对制订早期手术摘除方案有重要意义。
[Objective] To investigate the appropriate method of early diagnosis and accurate pre-operative 3-D orientation of maxillary embedded mesiodens by analyzing their growing pattern and radiographic manifestations. [ Method] Systematical clinical examination and X-ray orientation analysis were performed in 216 cases with embeded mesiodens. Statistical analysis on the growing features of impacted mesiodens （direction, pattern, shape, size）, imaging orientation and the clinical disturbing manifestations to adjacent permanent teeth was performed. [Results] This kind of supernumerary teeth were mostly conical-shaped with the average length of 1.6 cm and the average diameter of 0.6 cm. They often appeared inverted in the maxilla （83.5%） and were mostly located in the palatal region of permanent central incisor （76.5%）. Widened diastema （36.6%）, retortion （33.3%）, and disturbed eruption （19.9%） were the most common clinical manifestations in patients with maxillary embeded mesiodens. The supernumerary teeth which were lateral to the permanent central incisor have much more disturbance than that superior to central incisor （P〈 0.01）. [Conclusion] Maxillary impacted mesiodens mostly appear conical-shaped and have great negative effect on the involved central incisors by cringing to their palatal or medial regions. Accurate 3-D orientation can be achieved by parallactic orientation method, which has great significance to make a therapeutic plan for early removal of cmbeded mesiodens.
出处
《中山大学学报（医学科学版）》
CAS
CSCD
北大核心
2005年第5期563-565,共3页
Journal of Sun Yat-Sen University:Medical Sciences
基金
广东省科技攻关项目(980012)
关键词
正中多生牙
埋伏多生牙
上颌中切牙
X线
mesiodens
embeded supernumerary teeth
maxillary incisor
X-ray
作者简介
古向生（1955-），男，广东五华人，硕士，副主任医师。
