Prevalence and distribution of developmental enamel defects in primary dentition of Chinese children 3–5 years old

Abstract A total of 1344 children, 3–5 yr old, from two rural counties, Haidian and Miyun, close to Beijing, China, were examined in 1992. A modified DDE Index was employed in this study, and a pre‐designed formula was used to calculate an enamel detect score (EDS) for each individual in the study. Oral examination was performed by one dentist under natural light using a standard mouth mirror and dental probe. Developmental enamel lesions were diagnosed without drying or cleaning the teeth prior to examination. Results from this study showed that primary teeth with defective enamel were seen in 23.9% of the children examined, opacity in 1.6%, and hypoplasia in 22.2%. Among the teeth, maxillary central and lateral incisors were affected by enamel hypoplasia most often (40.8% and 39.2%), followed by maxillary canines (25.7%), maxillary 1st molars (22.1%), and mandibular 1st molars (18.5%). The enamel defects occurred more frequently on the buccal surfaces of teeth than on any other surface. The study did not find a significant association of the children's age, family socioeconomic status, and anthropometric measurements with the distribution of enamel defects. However, there was a significantly higher prevalence of teeth with defects in males compared to females (P < 0.001), as well as mean tooth surfaces with defects (P < 0.05), and mean EDS (P < 0.05). Children born prematurely were shown to have four times more enamel lesions than children who were full term (P < 0.01). Children with low birth weight also showed a statistically significant higher prevalence of enamel defects (P < 0.05) and a greater severity of hypoplastic lesions measured by EDS (P < 0.05) than those with normal birth weight. The results indicate that nutrition during fetal development is important in determining normal development of enamel in primary teeth. Nutritional status (diagnosed by anthropometric measurements) after the critical period was not associated with enamel defects induced earlier in life. The study suggested, therefore, that nutrition is important for maintaining proper development of the teeth only during the critical period when teeth are susceptible to the formation of defects.