Mandibular advancement splints are effective in treating snoring and obstructive sleep apnea, according to research presented June 11 at the American Academy of Dental Sleep Medicine annual meeting in Minneapolis.
Clinical assessment of MAS efficacy in the treatment of snoring and obstructive sleep apnea is based predominantly on subjective reports by the patient and partner, and less commonly on the apnea hypopnea index (AHI), the average number of pauses in breathing that occur per hour of sleep.
The current study used a portable device with sensors contained in a mattress overlay to measure AHI by detecting and recording snoring, breathing, and body movements. The study involved data from 42 men and women for two consecutive nights. The subjects slept the first night without the MAS and the second night with the MAS advanced to 70% of maximum jaw protrusion.
Results show that MAS treatment reduced the average AHI from 10.3 events per hour to 3.8 events per hour. The respiratory event movement index, which records more types of events than AHI, was reduced from 15.9 events per hour to 7.6 events per hour.
The researchers also found a decrease in the percentage of patients who snored from 38% without the MAS to 15% with the MAS. Snoring decreased overall, but 12 of the 42 subjects still snored for greater than 25% of the night, with several having substantial increases in snoring.
"The primary findings in our study were that MAS devices were effective in the treatment of OSA by reducing AHI in moderate and severe OSA patients," said principal investigator and lead author Joachim Ngiam, BDS. "Overall, significant reductions in snoring were found to occur with MAS therapy with greater changes seen in OSA patients."
In addition, the researchers found what appeared to be a devolutionary effect with MAS treatment in attenuating or reversing the progression of a snorer's disease to OSA, as a substantial number of patients transitioned to lower AHI and snoring categories.
Despite favorable reductions in AHI with MAS treatment, snoring may persist and patients may question treatment success, indicating a need for quantification of therapy efficacy.
"Although significant reductions in AHI and snoring were observed, residual snoring may persist or even increase in some patients," Dr. Ngiam said. "A significant proportion of patients (29%) still snored greater than 25% of total sleep time, with several having substantial increases despite MAS therapy."
