Association between oronasopharyngeal abnormalities and malocclusion in Northeastern Brazilian preschoolers.

Objective: Evidence is contradictory regarding the association between oronasopharyngeal abnormalities and malocclusion. The aim of the present study was to assess the association between oronasopharyngeal abnormalities and malocclusion (anterior open bite and posterior crossbite) in preschoolers.
Methods: A cross-sectional study was conducted with a representative sample of 732 preschoolers aged 3-5 years old selected randomly from private and public preschools. Anterior open bite (AOB) and posterior crossbite (PC) were evaluated through a clinical exam. Parents/caregivers answered a questionnaire addressing sociodemographic indicators and oronasopharyngeal issues. Statistical analysis involved descriptive analysis and Poisson regression (p < 0.05).
Results: The prevalences of AOB and PC were 21.0% and 11.6%, respectively. Being three years old (PR = 1.244; 95% CI = 1.110-1.394; p < 0.001), being four years old (PR = 1.144; 95% CI = 1.110 - 1.394; p = 0.015), absence of allergy (PR = 1.158; 95% CI = 1.057 - 1.269; p = 0.002), not having undergone nose surgery (PR = 1.152; 95% CI = 1.041 - 1.275; p = 0.006) and having a sore throat more than five times in the same year (PR = 1.118; 95% CI = 1.011 - 1.237; p = 0.030) were significantly associated with AOB. The absence of asthma (PR = 1.082; 95% CI = 1.012 - 1.156; p = 0.020), not having undergone throat surgery (PR = 1.112; 95% CI = 1.068 - 1.158; p < 0.001) and not having undergone nose surgery (PR = 1.114; 95% CI = 1.069 - 1.160; p < 0.001) remained associated with PC.
Conclusion: Significant associations were found between oronasopharyngeal-reported abnormalities and the presence of AOB and PC in preschoolers.