Dental side-effects of mandibular advancement splint wear in patients who snore

(a) To evaluate the longer term orthodontic side-effects of a Herbst mandibular advancement splint (MAS) in subjects with sleep disordered breathing. (b) To determine whether these are related to dental occlusion, degree of mandibular advancement or duration of appliance wear.

Retrospective, cohort study.

Teaching hospital dental school.

Subjects with sleep disordered breathing who had been wearing an MAS regularly (a minimum of 5 h per night, six nights a week) for at least 2 years. Of 192 subjects who were identified, 30 fulfilled the inclusion criteria and were prepared to attend for review.

Dental casts were obtained and BMI and Epworth Sleepiness Scale scores recorded. These data were compared with those collected when the subject was first referred. A questionnaire was completed concerning MAS use, side-effects and any problems associated with the device.

Changes in incisor tooth position.

Median duration of MAS wear was 3.64 years. Small, statistically significant reductions in both vertical (-0.4 mm) and horizontal (-0.5 mm) overlap of the incisor teeth were found. This correlated with the degree of vertical opening of the MAS but was not related to the amount of mandibular protrusion or the duration of appliance wear.

Patients who are considered suitable for MAS should be warned that dental changes may occur. Thus referring surgeons should also be aware of this possibility.