The effect of changes in the intermaxillary distance in mandibular advancement splints as a treatment of obstructive sleep apnea

Objective To evaluate the effect of intermaxillary space variation induced by mandibular advancement splints (MAS) constructed with three different interocclusal distances on the efficacy of the treatment of the obstructive sleep apnea. Materials and Methods Ten patients were selected after polysomnography from the Sleep Laboratory in Tanta University. At the beginning of the study all patients were asked to complete the Epworth sleepiness scale and after the treatment period. Each patient received three MAS constructed with intermaxillary distance of 4, 8, and 10 mm and patients were recalled after 4–6 weeks for follow‑up study using nasopharyngoscopy and polysomnogram after each appliance. The patients were instructed to withdraw and stop the use of their appliance for at least 1 week before using the next appliance. The recorded data for each patient with the three appliances were collected, tabulated and statistically analyzed using t‑paired test and Friedman’s test. Results There was statistically significant difference between the baseline records and the records obtained after the use of each MAS appliance (P 0.05). Conclusion The use of MAS appliance with increased vertical dimension improved the velopharyngeal caliper and improvement in the polysomnographic variables especially Apnea/Hypopnea Index, sleep efficiency and Arousal Index was observed.