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Updated: Apr 18, 2026

Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
Published on: August 22, 2022
Primary mandibular first molar with single root and single canal: a case report of a rare morphology
Zahra Bahrololoomi1, Roya Ghafourifard2, Ali Asghar Soleimani2
1Associate Professor, Department of Pediatric Dental School, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Abstract:
Single rooted primary mandibular first molar is a rare developmental anomaly. Literatures reveal that failure of invagination of Hertwig's epithelial root sheath leads to this unusual root form. Thorough knowledge of root canal morphology and anatomical variations of primary teeth can help a pediatric dentist in successful root canal treatment. Hereby, we describe two cases of primary mandibular first molars with an unusual morphology as a single root called pyramidal molar.
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