The aim of this study was to elucidate the details of root resorption of deciduous teeth, such as changes in the length of the root and the resorption morphology and to investigate the relationship between root resorption and the developmental status of permanent teeth.
The study involved 159 mandibular second deciduous molars. The teeth which were examined had been extracted from children. The length of the roots was measured and divided into four classes, depending on the degree of resorption of the two roots. The degree and morphology of resorption were investigated. The mandible from dry skulls classified into four eruption stages of deciduous and mixed dentition were observed with soft radiography.