Comparison of Dental Side Effects between Two Oral Appliances for Sleep Apnea - a pilot study

Oral appliances (OAs) represent a widespread treatment modality for patients with mild to moderate obstructive sleep apnea (OSA). OAs exist in many designs, but it is unknown if there are differences in terms of side effects between the various types. The aim of this pilot study was therefore to evaluate two OA designs, one rigid type of appliance (OAR) and a more flexible one (OAF) regarding increased crowding of the lower front teeth. Six patients with a mean age of 58 years (3 men) who had used OAR and another six patients with a mean age of 63 years (4 men) who had used OAF for at least 2 years were included in the study. The patients responded to a questionnaire and had impressions for plaster casts for analysis of the irregularity in the front teeth using Little's index. The distances between the contacts points between two adjacent teeth were measured in the frontal areas. The OAF group had an increased irregularity of lower front teeth with 0.89 mm (p>0.05) and the OAR group had a reduced irregularity of 0.58 mm (p>0.05). The difference between the groups was significant (p=0.041). There were no changes in crowding of the upper incisors in either group. Patient satisfaction with treatment did not differ between the groups. The present results indicate that a flexible type of OA increase the irregularity of the lower front teeth compared with a more rigid OA. The results should be confirmed in a larger sample.