上颌第一恒磨牙根管形态的透明牙观察

Root and Canal Morphology of the Maxillary Permanent First Molars Using a Clearing Technique

目的:运用透明技术研究上颌第一恒磨牙根管形态。方法:收集离体上颌第一恒磨牙90颗保存在10%的福尔马林液中,将离体牙制作成透明标本,按Vertucci的标准对根管分类并记录根尖孔数目。结果:上颌第一恒磨牙均为三根牙。所有的腭根及绝大多数的远颊根(97.78%)为单根管。近颊根单根管率为22.22%,双根管率为73.34%,三根管率为4.44%,以Ⅱ型和Ⅳ型根管最为普遍。管间侧支在近颊根多见,侧支根管多见于根尖1/3。结论:上颌第一恒磨牙近颊根多根管率较高(77.78%),掌握其解剖形态对提高根管治疗成功率具有重要的临床意义。

To investigate the root and canal morphology of the maxillary permanent first molars using a clearing technique. Methods： A total of ninety extracted human maxillary first molars were used. The teeth were stored in 10% formalin solution after extraction. Then the specimens were studied using a clearing technique. The cleared teeth were examined under good lighting with a magnifying（×3）, and examination of the root canal systems of the teeth was based on the vetucci＇s classification. The number of apical foramina were recorded. Results： All the maxillary first molars had three separated root. The majority of palatal（100%） and disto-buccal（97. 78%） roots possessed one canal（type I ）. 22. 220/00 of mesiobuccal root bad one canal. 73. 340/00 of mesiobuccal root had two canals and type Ⅱ and IV were the most common. 4. 440/00 teeth had three root canals. Intercanal communications were most prevalent in mesiobuccal roots. Lateral canals were most prevalent in the apical third of the roots of the maxillary first molars. Conclusions： The maxillary first permanent molar has a high ratio of more than one root canal in mesiobuccal root（77.78%）.