A study of the development of the permanent dentition in very low birthweight children.

There have been no previous studies on dental maturation of prematurely born, very low birthweight (< 1500 g, VLBW) Caucasian children. This study investigated dental development and prevalence of enamel defects in a group of 55 VLBW children (mean age at dental examination 7.7 +/- 2.2 years, mean birthweight 1203 +/- 240 g, and mean gestational age 29.8 +/- 2.4 weeks) compared to 55 normal birthweight (NBW) children matched for race, sex, and age. Dental maturity was determined from panoramic radiographs. Overall, VLBW children experienced a delay in dental maturation of approximately 0.29 +/- 0.54 years compared with NBW children (P < 0.02). The VLBW children younger than 6 years of age showed the greatest delay of 0.31 +/- 0.68 years (P < 0.001). In contrast, children aged 9 years and older had no difference in their dental ages compared to controls (P > 0.01), showing that "catch-up" growth had occurred by age 9 years. Children of birthweight < 1000 g with gestational ages < 30 weeks showed the greatest lag period in dental maturation. Clinical examination also showed that VLBW children had a higher percentage of enamel defects in the permanent first molars (21% versus 11%, P < 0.02) and lateral incisors (12% versus 0%, P < 0.01). As the permanent teeth commence their mineralization of few mouths after premature birth, it is hypothesized that there is persistent systemic derangement sufficient to affect enamel formation postnatally for some time in VLBW children.