Ultrastructural morphologic pattern in the roots of deciduous teeth in different stages of physiologic resorption

Aim: This study was conducted to assess the ultrastructural morphological pattern of resorption in the hard tissues of the root of deciduous teeth at different stages of resorption. Material and methods: 35 extracted deciduous teeth in different stages of resorption were collected. Standardized photos of the teeth were taken from all the aspects. The remaining root length (RRL) as described by the distance between the trough of the cervical line and the deepest point of resorption on the root surface was measured. Teeth were grouped into 4 groups based on the RRL. After surface preparation, the teeth were mounted in clear self cured acrylic. The teeth were then analysed for the ultrastructural morphology in different of stages of physiologic resorption using Smart SEM Version 5.05, Carl Zeiss NTS Ltd, Germany. Results: Ultrastructurally stage 1 is characterized by the presence of individual isolated resorption craters in the apical region. They however increase in the number in the furcal region. As the process continues further along the different stages, these craters deepen, which at higher magnifications shows the lacunae housing the odontoclasts following a linear path of resorption. The pattern clearly describes single large odontoclast leading the path of resorption with other odontoclasts following the path in linear manner. Conclusion: The cellular and ultrastructural changes are affected by the stages of resorption and each stage have the characteristic features that depict the resorptive process. Clinical significance: This study provides the knowledge of comprehensive morphologic pattern which is characteristic of each stage of physiologic resorption. (c) 2020 Japanese Society of Pediatric Dentistry. Published by Elsevier Ltd. All rights reserved.