Abstract
We experienced a rare case of multiple impacted teeth and inversion of the upper right second deciduous molar and upper right second premolar in a 13 year 8 month, old boy.
1) Radiographs showed impaction of the upper right canine, occurrence of supernumerary teeth between the lower first and second premolars and at the distal region of the upper right second premolar and inversion of the upper right second deciduous molar and the upper right second premolar.
2) It was judged histologically and morphologically that the upper right second deciduous molar was situated at the right maxillary sinus region and the upper right second premolar was situated at the distal site between the upper right first premolar and the upper right first molar.
3) We considered that the impacted upper right second premolar was disturbed in the formation of the tooth crown by the supernumerary tooth and inversion of the upper right second deciduous molar and the upper right second premolar was caused by the remaining second premolar above the second deciduous molar at the initiation of tooth development
