[Morphological studies on the cervical line of the deciduous teeth. Three-dimensional observation on mandibular second deciduous molars].

Morphological observation of cervical line of deciduous teeth has been studied in many ways. But there are few reports of research observed from a three-dimensional view point. Using twenty seven mandibular right second deciduous molars, we studied morphological observation of cervical line of physiologically sound deciduous teeth by three-dimensional measuring system. Three-dimensional coordinate values were obtained from the center pit and the mesiolingual cusp of mandibular right second deciduous molar. We used the three-dimensional measuring system (Microcode BX 303: MITUTOYO), and then the three-dimensional coordinate values obtained were transferred to a microcomputer for analysis. As a result the figure of cervical line of the mandibular right second deciduous molar observed from the XY-axis can be grouped into two, and the Z-axis can be classified two types, and we found one new method related to the morphological observation of cervical line.