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Updated: Jun 28, 2026
Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
Published on: August 22, 2022
[Observation of the roots and root canals of 442 maxillary first premolars]
1Department of Endodontics, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China. realcxl@126.com
Purpose:
To investigate the root and root canal anatomical features of maxillary first premolars in 422 teeth.
Methods:
422 maxillary first premolars were collected to statistically analyze the root types by sex and to observe the root canals by clearing technique; Vertucci's classification was adopted to get the percentage of each root canal type. The data were analyzed with SPSS11.5 software package.
Results:
(1)Significant gender difference was found in 422 teeth in terms of the percentage of one root(total 57.36%; male 33.58%; female 62.68%), two roots(total 41.47%; male 62.68%; female 33.33%) and three roots(total 1.18%; male 3.73%; female 0%) (P<0.01). (2)In the 422 transparent specimens of the teeth, totally 9 types of root canals were discovered with the percentage of type I(10.12%), II(10.60%), III(6.02%), IV(56.63%), V(12.05%), VI(1.93%), VII(0.72%), VIII(1.45%), IX(0.48%).
Conclusions:
Understanding of the various and gender-different morphology of the roots and complex root canals of maxillary first premolars, is of great value for the diagnosis and root canal therapy.
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