The role of obstructive tonsils in ventilatory disorders and abnormal lip posture is widely discussed in the literature but remains controversial. The data reported on the probable relationship between obstructive tonsils and an existing breathing disorder or lip incompetence were subjective. The purpose of this study was to evaluate the relationship between the obstructive character of the tonsils and the type of ventilation and lip posture.

This is a cross-sectional study performed in children aged from 6 to 12 years old. The subjects were divided into two groups (A and B) according to the obstructive or non-obstructive character of the palatal tonsils. Type of ventilation and lip posture at rest were recorded for each child. The collected data were analysed using the SPSS 20.0 software (for Windows). A Student's t-test and a Chi² test were respectively used to compare quantitative and qualitative variables according to the obstructive character of the tonsils for each group. The level of significance is fixed at P=0.05.

The subjects in group B with obstructive palatal tonsils were significantly more likely to oral breathing and lip incompetence than the subjects with non-obstructive tonsils (group A).

The clinical examination of children with ventilatory and postural disorders with lip incompetence must be directed towards the search for associated obstructive palatal tonsils in order to plan an early etiological treatment. This would allow to avoid subsequent problems in the dentofacial structures.