Open Bite in Prematurely Born Children

Resident: Swan
Title: Open Bite in Prematurely Born Children
Authors: Harila et al.
Journal: Journal of Dentistry for Children 74:3, 2007

Purpose: "examine the expression of open bite in prematurely born children and discuss the etiological factors that may lead to bite it."

Intro: Preterm birth has been associated with various dentofacial findings, including enamel hypoplasia, dental caries, palatal deformities, early eruption of permanent incisors and first molars, and occlusal asymmetries. This study set out to determine any correlation between PTB and anterior open bite.

Methods: N=2132: 328 Preterm and 1804 fullterm born children. 60 Caucasian children and 268 African American children in preterm group, 803 Caucasian and 1001 AA children in control group. All children were among 60,000 in Collaborative Perinatal Study of National Institute of Neurological Disorders and Stroke. Dental examinations were carried out in a standardized way with casts made and photographs taken between ages 6 and 12 in 95% of cases. Casts were examined, arch dimensions and occlusal variables (incl. molar and canine relationships) were determined. Mean age at which casts were taken was 8.8 years. Vertical open bite was determined only for "fully erupted teeth." Results were analyzed with chi-square analysis.

Results: AA children had higher incidence of anterior open bite than Caucasian children (9 vs 3%). Girls had greater incidence than boys (8 vs 6%).
Greater prevalence of ant. open bite was found in the premature children (9 vs 7%). In preterm AA boys, prevalence was 11% compared to 8% among controls. When Caucasian and AA children were combined, prevalence of ant open bite was greater for preterm boys (8 vs 5%) and for preterm girls (9 vs 8%).

Discussion: According to literature, prevalence of open bite in gen. pop. aged 8-11 is 4%. In US, incidence of open bit is approx. 16% in AA population and 4% in Caucasian population. The results of this study conform to these findings.
Literature also shows that most common reason for ant. open bite is non-nutritive sucking habits, but also included in the list are mouth breathing, tongue thrusting, myopathies of facial muscles. It is recommended that children be guided to stop a non-nutritive sucking habit by about age 2.

"Preterm children are predisposed to several systemic derangements, respiratory problems, and other infections. Additionally, the head posture may be altered due to difficulties with breathing, which can interfere with the developing teeth and may help explain the increased prevalence of open bite in some preterm children."

Conclusions: Greater prevalence of ant. open bite among AA children compared to Caucasian and in preterm children compared to full term children.

Assessment: Weak article in my opinion. Briefly hypothesized why preterm babies might have more open bite tendency, but even then it was only a sentence and a weak one at that. Also, only "fully erupted teeth" on the casts were evaluated for open bite. It seems hard to know when a tooth is fully erupted on a cast, and I wonder if this resulted in some false positives and false negatives as they evaluated them.