Developmental enamel defects of primary incisors in preterm infants with very low and extremely low birthweight. A case- control study.

To determine the prevalence of developmental defects of enamel (DDE) in primary incisors of preterm very low birthweight (VLBW) and extremely low birthweight (ELBW) one-year-old infants and to compare the findings with fullterm one-year-old normal birthweight (NBW) infants. All infants were enrolled in the case-control study at birth. Personal information and medical histories were obtained through interviews with parents and from medical hospital records. The presence of DDE in primary incisors was evaluated in 82 one-year old preterm infants delivered with VLBW, in 50 ELBW and in 58 fullterm NBW infants. The data were statistically analysed by ANOVA and chi-square tests, and a statistical significance level p<0.05 was established. Results DDE were diagnosed in 19 (23.2 %) preterm VLBW infants, in 27 (54%) ELBW infants and in 4 (6.9%) infants of the control group. The most frequent DDE found in the case group was hypoplasia in 10 (12.2%) VLBW infants and in 14 (28%) ELBW infants. The opacities were found in 6 (7.3%) VLBW infants and in 8 (16%) ELBW infants. The results of the study confirmed a significantly higher prevalence of DDE in the primary incisors in preterm ELBW infants than in VLBW infants and than in full term NBW infants.