Association between 3D characteristics of single unilaterally impacted mesiodens and root development of adjacent maxillary central incisors: a retrospective study with cone-beam computed tomography.

Objectives: This study aimed to evaluate the detrimental effects of single unilaterally impacted mesiodens on the root development of adjacent maxillary central incisors and to explore the key influencing factors.

Methods: A total of 552 patients aged 5-12 years with single unilaterally impacted mesiodens were included in the study. The maxillary central incisor with greater overlap with the mesiodens in the coronal view was identified as the affected tooth, while the contralateral central incisor served as the control one. Cone-beam computed tomography (CBCT) data for these patients were retrospectively analyzed to compare the root lengths and root formation stages of the maxillary central incisors on both sides. Multivariate logistic regression and generalized linear models were used to investigate the critical 3-dimensional (3D) characteristics that influence the root development of adjacent maxillary central incisors.

Results: Maxillary central incisors on the affected side exhibited significantly shorter root lengths and less-advanced root formation stages compared to those on the control side. Impacted mesiodens with tuberculate or germ morphology, normal or undefined orientation, and a position superior to dental cervix of contralateral central incisor were associated with higher risk of impairing root development of adjacent central incisors.

Conclusions: Impacted mesiodens can impair the root development of adjacent central incisors. Early removal of high-risk mesiodens is essential for safeguarding the future development of adjacent maxillary central incisors.