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Upper airway obstuction in class II patients. Effects of Andresen activator on the anatomy of pharingeal airway passage. Cone beam evalution.

AIM
The aim of this study is to assess the response and changes on pharyngeal airway passage (PAP) to class II Andresen appliance in class II growing patients with obstructive sleep apnea syndrome (OSAS).


METHODS
The sample consisted of forty patients with a class II malocclusion in the age range of 9 to 14 years with mandibular retrusion and OSAS and ten control group subjects. A CBCT was taken before treatment (T0) and a second one after a follow-up period of approximately 16 months (T1). The dimensions of PAP were determined according to the method described by Jena et al. with Mimics program. The following parameters were considered: DOP, DPH, MP-H, PAS, PNS-U, SNA, SNB, ANB. The statistical analysis was carried out with t test.


RESULTS
The change in ANB, SNB, MP-H, PNS-U, PAS was significantly more in the patients undergoing treatment as compared to the control group. The improvement of DOP and DPH among the treatment group subjects was significantly more compared to the control group subjects.


CONCLUSIONS
Class II correction by functional appliances during childhood might help to eliminate the adaptive changes in the upper airway and predisposing factors to OSAS, thus decreasing the risk of OSAS development in adulthood.