Three-dimension model of root canal morphology of primary maxillary incisors by micro-computed tomography study

Abstract

The success of root canal treatment for deciduous teeth depends upon the shape of the root canal, among other factors. Despite this, there are limited reports on the use of high-resolution micro-CT to describe the root canal morphology of primary maxillary incisors. In this study, we aimed to create a three-dimensional (3D) digital model of the root canal morphology of primary maxillary incisors using microcomputed tomography (micro-CT). To provide a reference for the development of restorative posts for the primary maxillary incisors. Primary maxillary central and lateral incisors (n = 10 each) were analysed. Micro-computed tomography was used to conduct 3D analyses of the root canal system of the primary maxillary incisors. The canal volume and surface area of the primary maxillary central incisors were larger than those of the primary maxillary lateral incisors. The structural model index value was significantly lower in central incisors. At the cervical level and the interface between the cervical and middle one-third cross-sectional levels, the root canals of the primary maxillary lateral incisors were significantly rounder. The labio-palatal dimension and the diameters of the central incisors at the four different levels were significantly smaller than the diameter of the mesio-distal dimension. The taper of the central and lateral incisors gradually increased from the apical one-third to the cervical one-third in the labio-palatal dimension. The data obtained from the 3D analysis of maxillary incisors in this study will contribute to the design of root canal posts.

Keywords: Micro-computed tomography; Morphology; Primary maxillary incisors; Root canal system.

Fig. 1

Exemplary three-dimensional models of primary maxillary central incisors (a–c) and their corresponding root canal morphology (d–f). Generally, the roots of the primary central incisors exhibit a wide and flat shape, featuring a single root canal without any apical ramifications or lateral canals.

Fig. 2

Exemplary three-dimensional models of primary maxillary lateral incisors (a–c) and their respective root canal morphology (d–f). Generally, the roots of the lateral incisors are narrow and thick, hosting a single canal without any apical ramifications or lateral canals.

Fig. 3

Three-dimensional reconstruction of the pulp cavity of primary central incisors (a) and lateral incisors (b), which showcases the variations in the two-dimensional configuration of the root canal at different levels of the root.