Correlations between transversal discrepancies of the upper maxilla and oral breathing

The aim of the study was to evaluate the relationship between malocclusion with cross-bite and permeability of the upper airways, and to observe the cephalometric changes of the rhinopharyngeal space after rapid palatal expansion therapy.

The sample consisted of 17 patients (age 9-12) of which 10 were males, followed up for a period of 1 year at the Department of Paediatric Dentistry of the Dental Clinic of the University of Pisa. Clinical, radiographical and otolaryngological examinations were carried out before treatment with palatal expansor. After expansor activation, each patient underwent an otolaryngological and orthodontic evaluation followed by rhinomanometry, and, in the cooperating children, endoscopy was also performed. After 6 and 12 months from the beginning of the treatment, each patient was examined again and the radiographic examination was repeated.

The cephalometric analysis exhibited an increase of the rhinopharyngeal space in 16 children. Furthermore all the 17 patients showed, after therapy, an increase of the transverse dimension of the upper jaw, measured on the postero-anterior teleradiography. On the other hand, the otolaryngological examination, and in particular rhinomanometry, exhibited an improvement of the flow and of right and left nasal resistance only in 3 children, while in 6 children the graph remained unchanged, and in 8 children it worsened. The results show that the rapid palatal expansion produces an improvement of the transversal skeletal discrepancy, and an improvement of the permeability of the upper airways. To make a correct diagnosis lateral and postero-anterior teleradiography, and a cephalometric analysis are needed; instead the otolaryngological examination in our opinion it is not an essential diagnostic examination for this kind of pathology.