Evaluation of Morphological and Chemical Composition of Dental Pulp Stones: A Combined Microanalytical Approach

Introduction: Pulp stones (PSs) are mineralized ectopic structures within the dental pulp that vary in morphology, composition, and location. Their etiology remains uncertain and poses clinical challenges in endodontics. This study hypothesized that combined analytical techniques would enhance understanding of PS morphology and composition, facilitating clinical management of complex cases. Methods: Fifteen permanent molars with radiographic evidence of PSs were analyzed using microcomputed tomography (μ-CT), light microscopy, and scanning electron microscopy associated with energy-dispersive spectroscopy (SEM-EDS). The samples underwent qualitative and quantitative assessments to explore their morphology, distribution, and chemical composition. Statistical analysis was conducted using one-way analysis of variance to evaluate differences in Ca/P ratios between PS and dentin, with significance set at P < .05. Results: μ-CT and histological evaluations revealed distinct morphological differences between coronal and radicular PS. Coronal PS exhibited regular nodular or mold shapes, whereas radicular PS showed irregular and diffuse patterns. Histological findings highlighted the nature of PS as mineralized ectopic connective tissue in coronal regions. On the other hand, radicular PSs displayed linear arrangement of collagen fibers intertwined with vascular bundles. SEM-EDS demonstrated no significant differences in mineralization between PS and dentin, with comparable Ca/P ratios. Conclusions: PSs exhibit distinct morphological and structural characteristics depending on their location. Despite these differences, PSs and dentin share similar chemical compositions, as demonstrated by similar Ca/P ratios. The combined microanalytical approach employed provides novel insights into PS morphology and composition, offering a foundation for translational advancements in diagnostic and therapeutic strategies.