The pattern and prevalence of hypodontia in Koreans

OBJECTIVE: The objective of this study was to evaluate the pattern and prevalence of hypodontia in the Korean population along with its association with the dental and skeletal polymorphisms. SUBJECTS AND MATERIALS: The diagnostic materials including casts, panoramic radiographs, and lateral cephalograms of 1622 Korean subjects (611 males, 1011 females) were used to evaluate the pattern and prevalence of hypodontia as well as its association with the congenital absence of the third molar. The changes in the tooth size and skeletal characteristics of the hypodontia group were evaluated using cast/cephalometric analysis and compared with the standard values of normal occlusion in Koreans. RESULTS: The prevalence of hypodontia in Koreans was 11.2%. The mandibular lateral incisor and second premolar were the most frequently absent. Congenital absence of the third molar was observed more frequently in the hypodontia group than in the non-hypodontia group. The prevalence of hypodontia in Class III malocclusion was significantly higher than in Class I or Class II malocclusion. CONCLUSION: The pattern and prevalence of hypodontia can vary in different ethnic groups. In Koreans, the special features of hypodontia were its association with a higher level of congenital missing third molars and skeletal Class III malocclusion.