BMC Oral Health. 2026 Feb 17. doi: 10.1186/s12903-026-07919-1. Online ahead of print.
ABSTRACT
BACKGROUND: Molar-incisor hypomineralization (MIH) is a prevalent developmental enamel defect that frequently affects permanent molars and is associated with increased dentin permeability, hypersensitivity, and a higher risk of pulpal inflammation. These clinical features may necessitate endodontic treatment at an early age; however, information regarding potential variations in root canal morphology in MIH-affected molars remains limited. This study aimed to investigate the root canal morphology of hypomineralized permanent molars and compare it with that of healthy molars via microcomputed tomography (µCT).
METHODS: A total of sixty extracted permanent molars were included in this study, comprising thirty hypomineralized teeth and thirty healthy control teeth. All samples were scanned using a SkyScan 1172 µCT system. Root canal configurations were classified according to the Sert and Bayırlı classification system, and isthmus types were assessed according to the system described by Hsu and Kim. The numbers of major and minor apical foramina were recorded. Morphometric analyses included measurements of canal area, cervical width, and cervical thickness. All the data were statistically analyzed via independent t tests, with the level of significance set at p < 0.05.
RESULTS: The most common root canal configuration in both groups was Type I, defined as the presence of two canals without noticeable communication. Hypomineralized teeth exhibited a significantly greater number of minor apical foramina in the middle third of the root (p = 0.016) as well as a greater total number of minor apical foramina compared with healthy teeth (p = 0.047). The cervical width was significantly greater in the hypomineralized molars (p = 0.02), whereas no significant differences were observed in the cervical thickness, canal area, or isthmus distribution between the two groups.
CONCLUSIONS: µCT analysis demonstrated distinct morphological differences between hypomineralized and healthy permanent molars, particularly regarding the number of minor apical foramina and cervical width. These findings underscore the need to consider potential root canal variations during endodontic assessment and treatment planning in MIH-affected molars.
PMID:41703541 | DOI:10.1186/s12903-026-07919-1
