Is premature birth an orthodontic risk factor? A controlled epidemiological clinical study.

INTRODUCTION

Although a "catch-up" growth occurs in early childhood, respiratory system immaturity and the use of oral and naso-gastric probes for prematurely born children are responsible for palatal and cranio-facial alterations.

OBJECTIVE

To assess whether prematurity is a risk factor in orthodontics in terms of malocclusions, dysmorphoses and orthodontic treatment need compared to term-born children. To compare the differences of risk factors among these preterm birth subtypes according the severity.

MATERIALS AND METHODS

Distributed questionnaires within an orthodontic practice and in the Department of Odontology, Lyon Hospital, France. The evaluation criteria were calculated from the casts, photographs and radiographies carried out during the initial assessment. A statistical intergroup comparison was performed.

RESULTS

Of the 537 questionnaires obtained, 47 preterm patients and 150 term-born patients were included in our study. Preterm infants had significantly more bilateral crossed-occlusions than patients in the term group (P=0.003). In addition, very preterm and extremely preterm children had significantly more impacted tooth (P=0.049) and a higher Index of Orthodontic Treatment Need (IOTN grade 5, P=0.003) compared with term children.

CONCLUSION

Very preterm and extremely preterm births (occurring more than 8 weeks before the term) represent a risk factor in orthodontics and, therefore, a public health problem.