Abstract
The objective of this study was to elucidate influential factors of difficulty in treating impacted teeth.
At the Pedodontics Clinic of Iwate Medical University, we investigated 67teeth in 56 cases that we uncovered and extracted the impacted teeth.
The results were as follows:
1) The most common cause of dental impaction was malposition.
2) Girls had more impacted teeth than boys with about a 2: 1 ratio.3) The most frequently impacted position appeared on the maxillary central incisor.
4) It was possible to induce the dilacerations of the maxillary central incisor, even if the angle of crown axis inclination was about 100 degrees. It was possible to preserve the dilaceration, if the angle of root axis inclination was with in 90 degrees, by inducing them so that the toot apex was not exposed on the bone and administering crown restoration to them.
5) Most of the roots when the treatment began were incomplete.
6) When the treatment began, the period of eruption were delayed about 2years as compared with normal eruption time in all tooth types.
7) All of molars were exposed, but all of maxillary central incisors and canines were both exposed and extracted.
8) The induction period was shorter in teeth with incomplete roots than teeth with complete roots, being was 13 months on an average. Therefore it is thought that the treatment should be begun before the root has been completed, if the eruption time was delayed compared with the normal time.
9) After the treatment, pulp death, and root and alveolar bone absorption were not observed in the all cases.
10) The gingival swellings of the root apex position were observed in 4 maxillary central incisors, but there was no exposure of the root apex on the alveolar mucosa.
11) Gingival retraction at the cervical margin was observed in about 20% of the cases, but it was within 0.5 mm or 1.0 mm. Moreover this retraction was not effected by the method employed in the operation.
