By Sree Roy
Maxillomandibular advancement (MMA) as a therapy for obstructive sleep apnea (OSA) tends to be recommended only for patients with small and narrow pharyngeal space. But new research suggests that many more patients may clinically benefit from this type of sleep apnea surgery than sleep specialists assume, and that patient facial aesthetic outcomes are also not a barrier to treatment. This research abstract, published in the July 2022 issue of the Journal of Dental Sleep Medicine, won a student research award at the 2022 American Academy of Dental Sleep Medicine Annual Meeting.
In OSA patients with maxillary and/or mandibular deficiencies “the advancement of the maxilla and mandible was proven to be functionally and aesthetically beneficial,” says abstract first author Ning Zhou, DMD, MSc, in the department of oral and maxillofacial surgery at the University of Amsterdam in The Netherlands. “However, there is limited evidence available on the clinical efficacy of MMA in OSA patients without such deficiency.”
Prior to conducting their research, Zhou and co-investigators hypothesized that, consistent with many sleep specialists’ assumptions, the effects of maxillomandibular advancement on respiratory function would be better in OSA patients with deficiency than in those without it and that the changes in facial aesthetics followed by MMA were more acceptable in OSA patients with deficiency than in those without.
But that is not what they found.
“Our research found that the effects of MMA on respiratory function and facial esthetics were comparable between OSA patients with and without maxillomandibular anteroposterior deficiency,” says Zhou, who is also affiliated with the department of orofacial pain and dysfunction, Academic Centre for Dentistry Amsterdam (ACTA), at the University of Amsterdam and with Vrije Universiteit Amsterdam. “This supports the notion that MMA surgery could be considered as a viable treatment for OSA patients without such deficiency.”
While conducting the study, the team evaluated 61 MMA-treated OSA patients—40 with skeletal deficiency and 21 without—with both baseline and at least three-month follow-up polysomnographic data and lateral cephalograms in their retrospective study.
They found the apnea-hypopnea index reduction to be comparable between the two groups (26.3 ± 21.0 /h vs 37.1 ± 24.8 /h; P = 0.490). The satisfaction degrees in breathing (7.0 vs 6.5, P = 0.713) and facial esthetics (6.5 vs 7.0; P = 0.983) also did not differ significantly.
“In our study, the improvements in respiratory parameters and patients’ satisfaction in postoperative breathing were similar between the two groups,” Zhou says.
According to Zhou, previous research suggested that MMA could improve OSA by enlarging the pharyngeal space and stiffening the pharyngeal soft tissues. In their study, the enlargement of pharyngeal space after MMA was found to be similar between the two groups, which may partially explain the comparable efficacy of MMA between groups.
Additionally, both groups had similar surgical advancement. Approximately 70% of the patients were treated with a surgical protocol with a goal of 8-10 mm advancement. Further research should investigate whether the clinical efficacy of personalized planned MMA differs between patients with and without deficiency, says Zhou. And a validated questionnaire is preferable for the subjective assessments in future research.
Patients’ satisfaction with postoperative facial aesthetics was also comparable between the two groups. “Being aware of which factors are related to patients’ satisfaction with postoperative facial aesthetics might help to explain this finding, but further research is needed to answer this question,” says Zhou.
Sree Roy is editor of Sleep Review.
Zhou N, Ho JPTF, de Vries N, et al. Comparison of the effects of maxillomandibular advancement on respiratory function and facial esthetics between obstructive sleep apnea patients with and without maxillomandibular deficiency. JDSM. 10 Jul 2022;9(3):27-8 (Abstract #009).