The influence of the respiration disturbances on the growth and development of the orofacial complex.

The disturbances of orofacial functions lead to abnormal growth and development of the orofacial complex. The aim of the study was to determine the prevalence of incompetent lip seal and respiration disturbance, and to improve the understanding of correlation between incompetent lip seal and morphological malocclusions. In the sample of 84 children (45 girls and 39 boys, aged 8.96 +/- 0.66 years) a very high prevalence of the incompetent lip seal was found (35.72%). The study cast analysis was performed. The prevalence of the morphological malocclusion was significantly higher in the incompetent lip seal group (p < 0.001). There were also differences in types of malocclusions. The most frequent malocclusion found in incompetent lip seal was Class II / 1 malocclusion (53.3%). In the competent lip seal group this malocclusion was determined in only 15.57% (p < 0.001). Narrower upper dental arches, higher palate (p < 0.05) and larger overjet (p < 0.001) were found in incompetent lip seal group.