Comparison of occlusal traits in very preterm and full-term children. A case-control study

Abstract

OBJECTIVE: To compare occlusal traits of very preterm and full-term born children in the early mixed (T1) and late mixed/early permanent dentition stage (T2). MATERIAL AND METHODS: The sample consisted of 205 very preterm case children and 205 age- and geneder-matched full-term children. Data fot this register-based study were collected from the registers of Turku University hospital and the City of Turku Oral Health Care. Very preterm children were born before the 37th week of pregnancy with a birth weight under 1500g (2001–2003) or before the 32nd week of pregnancy (2004–2006). RESULTS: Among case children, the change in occlusal traits between T1 and T2 did not differ to those of control children except in overjet. The change in overjet between T1 and T2 was statistically significantly different between case and control groups in orthodontically treated children (group×dentition stage interaction effect, p=0.020). Orthodontically treated control children had lower odds of having atypical overjet (<0mm or >6mm) (OR=0.10, 95% CI 0.02–0.69, p=0.019 ) at T2 compared to T1 (at T1 n=21, at T2 n=21), while no statistically significant change in overjet in orthodontically treated case children was observed (OR=2.46, 95% CI 0.27–22.73, p=0.426) (at T1 n=40, at T2 n=28). CONCLUSIONS: The effects of very preterm birth are predominantly limited to the early stages of occlusal development. The occlusions of preterm children do not need extra follow-ups in the late mixed/early permanent dentition stages.