소구치에 발생한 Dens Evaginatus의 임상적 연구

A Clinical Study of Dens Evaginatus in the Premolars

The dens evaginatus was a developmental variation which has arisen as a result of an evagination of inner enamel epithelium into the enamel organ. It has been given various. names by authors and was thought to be confined to Mongolian race. This study was performed to observe the incidence of dens evaginatus, and its ill-effects on the teeth and surrounding structures in 6356 Korean students and 10227 Korean adults. In plaster model, analysis was performed in accordance with forms and location of dens evaginatus on the. occlusal surface in the premolars. The pathologic changes caused by dens evaginatus were observed in paralleling periapical radiograms The results were as follows: 1. The prevalence of dens evaginatus in the student's group was 2.6%, and showed no sex predilection in the occurrence of evaginated teeth. 2. The sequence of dens evaginatus was in order of mandibular 2nd premolar, mandibular 1st premolar, maxillary 2nd premolar, and maxillary 1st premolar, respectively. 3. Of the cases with dens evaginatus, 73.5 % occured bilaterally. 4. The nipple form was the most frequent in respect of elevation of tubercle on the, occlusal surface. 5. In the base form of the tubercle, the occurrence of grooved form was the highest. 6. In the maxilla, those cases which the tubercle arose from the lingual ridge of the buccal cusp were most predominant. And in the mandible, those cases which the tubercle arose from the center of the occlusal surface were the most frequent. 7. The pulpal and periapical complications were shown in 24.4% of evaginated teeth in. periapical radiogram.