To investigate the prevalence of eight morphological and numerical anomalies in the primary dentition of southern Chinese and to compare the prevalences with those from different ethnic groups.
Materials and Methods:
The material used in the study consisted of plaster casts and standardized panalipse radiographs collected from 936 randomly selected 5-year-old children (493 males and 443 females) in Hong Kong. The anomalies, hyperdontia, hypodontia, macrodontia, microdontia, double tooth, talon cusp, dens invaginatus and taurodontism, were assessed using diagnostic criteria that have been most often been cited in the published literature.
Of the eight dental anomalies examined, microdontia was the most common and occurred in 6.3% of southern Chinese children. This prevalence figure was much higher than that of other ethnic groups and it was mainly due to microdontia of the maxillary canines (4.3%). The prevalence of hypodontia (4.1%) was also the highest of all races, of which mandibular lateral incisors were the most frequently missing teeth in the southern Chinese (3.2%). Of the other dental anomalies studied, the prevalence of hyperdontia (2.8%) and double tooth (4.1%) were higher than reported for Caucasians.
Higher prevalences of microdont maxillary canines, and missing lateral mandibular incisors can be considered to be characteristics of the southern Chinese primary dentition.