Study on the length,number and transverse shape of the root canals of the first maxillary molars in vitro / 实用口腔医学杂志

ABSTRACT

Objective:To investigate the root length,number and the transverse shape of first maxillary molars using root sectioning technique. Methods:100 isolated first permanent maxillary molars from above 20 years old patients were collected. The roots were cross-sectioned in three parts(superior 1/3,middle 1/3 and apex 1/3) after measuring the length of roots. The transverse shape of root canals were observed under the stereomicroscope.The number and shape of root in three parts of roots were recorded. Results:The length of lingual root,MB and DB of the first maxillary molar is (13.82?1.51) mm;(13.06?1.12) mm and (11.64?0.85) mm respectively; complex degree of MB and DB of the first marxillar molar is very high. 51% double roots in superior 1/3 of MB were found. Above 50% dual roots in the middle 1/3and apex 1/3 in the mesiobuccal root of first maxillar molar were recorded. Conclusion:Root number and transverse configuration in MB and DB of first maxillary molar varied in different parts of roots; There may be double root canals in medium 1/3 and apex 1/3 in MB of first maxillary molar when one line type canal in superior 1/3 was found.