Eruption disturbances in Japanese children and adolescents

The aims of this report were to determine the nature of eruption disturbances and to establish the pattern of management for these teeth in a group of Japanese children and adolescents. Data were collected from the clinical records of patients in the Pediatric Dental Clinic of Niigata University Medical and Dental Hospital. There were 700 patients (364 males and 336 females) and 748 teeth (26 primary teeth and 722 permanent teeth) who were treated for eruption disturbances between 1979 and 2002. During this period, 17,365 new patients visited the clinic, of whom approximately 4% had eruption disturbances. The most frequently affected permanent teeth were the maxillary central incisors (38.6%), followed by the maxillary canines (15.4%). Of the permanent teeth, 52.5% were in males and 47.5 % in females. Although there were more cases of maxillary central incisors in males than in females, the number of cases involving maxillary canines was higher in females. Whereas delayed eruption was noted in 76.7% of maxillary central incisors, 18.6% were impacted and 4.7% demonstrated abnormal direction/position which required treatment. In contrast, a higher percentage (64.8%) of maxillary canines that showed abnormal direction/position was treated. Eruption disturbances were found in 40% of the patients during routine examinations. This suggests that regular routine examinations are important for pediatric dentists to detect and treat eruption disturbances early.