Patterns of Pulpal Mineralization in Mandibular Anteriors: A Micro-computed Tomography Analysis

Introduction: Current understanding of the morphology of pulpal mineralizations is limited. Understanding the specific location and type of such mineralizations will aid clinicians in diagnosis, case complexity assessment, and treatment planning. Therefore, this study correlated the appearance of a reduced canal volume (CV) in conventional radiographs with the presence of pulp mineralizations (PMs) utilizing micro-computed tomography (CT) analysis. The morphology of PMs utilizing micro-CT technology was also analyzed.

Methods: One hundred and twenty-one extracted permanent mandibular incisors were collected. Periapical radiographs were taken of the teeth to determine if a reduced canal space was present, in which case the sample was included for micro-CT assessment. Various descriptors for PM were then determined and these labels were then applied to the entire sample to demonstrate PM. Numerical analysis was undertaken for all teeth scanned; the following data was extracted: the presence or absence of PMs, types of PM, and their morphological structures; CVs were determined. Cohen's kappa test was used to assess intraexaminer agreement.

Results: Based on radiographic appearance, forty-two teeth were included for micro-CT analysis. PMs were demonstrable in 57% and absent 43% of teeth. When PMs were absent, the CV was significantly smaller compared to when they were present (P < .05). Discrete mineralizations were more frequently located in the coronal and middle thirds compared to diffuse mineralization (P < .01). No differences in the prevalence of the individual features of discrete or diffuse mineralizations were detected (P > .05).

Conclusions: Two detectable forms of PMs were found in micro-CT analysis at all levels of the canal: discrete and diffuse mineralizations. A reduced CV on a PA was reflective of mineralized changes within the pulp but the type of PM could not be determined. PMs occurred at any level of the root canal; clinicians need to be aware of this when performing root canal treatment.