Effectiveness of maxillo-mandibular advancement in obstructive sleep apnea patients with and without skeletal anomalies

Abstract

This study evaluates the effectiveness of maxillo-mandibular advancement (MMA) in patients with obstructive sleep apnea syndrome (OSAS), even those without skeletal anomalies, indicating the possibility of extending this procedure to more patients. Two groups with different skeletal patterns were studied pre- and post-surgery. Group 1 (11 patients) had severe or moderate OSAS and maxillo-mandibular hypoplasia and/or mandibular deformities (SNA angle 78° or less or SNA angle > 78° but with SNB < 65° and severe skeletal class II malocclusion). Group 2 (11 patients) had severe or moderate OSAS without maxillo-mandibular hypoplasia or deformity (SNA angle > 80°, dental class I occlusion). Analysis comprised: apnea hypopnea index (AHI), posterior airway space (PAS), SNA and SNB angles, Epworth sleepiness scale (ESS), body mass index (BMI), and a subjective standardized questionnaire about aesthetic appearance. All patients had increased PAS width and complete remission of objective and subjective OSAS symptoms evaluated by AHI and ESS. Results in both groups are comparable. Data were analysed using t -test; p < 0.005 was statistically significant. All patients were satisfied with the functional and aesthetic results. MMA is effective in patients with severe or moderate OSAS, even in those without skeletal and/or occlusal anomalies and can be considered in more patients.

The primary goal of the surgical approach to severe cases of obstructive sleep apnea syndrome (OSAS) is to resolve or significantly improve the clinical situation, thus avoiding the use of nasal-continuous positive airway pressure (N-CPAP), which is frequently badly tolerated or refused. About 50% of patients in the USA and 25% in Europe have poor compliance with ventilatory therapy .

Surgical techniques involving the soft tissues, such as uvulopalatopharyngoplasty , hyoid suspension , partial glossectomy and lingual suspension have given partial results, mainly in cases of medium to light severity . The only technique that has given good results, including in obese patients, is resection of the base of the tongue with hyoidoepiglottoplasty but it has a high incidence of intra-operative and postoperative complications and sequelae.

Surgical methods involving skeletal components of the oro-maxillo-facial area have gained ground. Initially, mandibular advancement alone was employed , followed by anterior-inferior mandibular osteotomy and, more recently, maxillo-mandibular advancement (MMA) surgery has been employed . With MMA, all the soft-tissue structures making up the pharyngeal walls are tightened at once; this stops them from collapsing, or reduces this occurrence, by acting on the suprahyoid and palatal muscles and on the lateral musculature of the pharynx. The tongue is also pulled forward. The result is a significant increase of posterior airway space (PAS) and the resolution of the syndrome in a high (95%) percentage of cases.

At first, MMA was suggested for patients with clinical and cephalometric patterns of mandible and maxilla retrusion, and in a second stage of treatment, after nasal or palatal surgery without significant improvement . Later studies recommended the use of MMA as the first surgical choice in patients with severe OSAS and cranio-facial anomalies .

Although it is logical to advance both jaws in patients with clinical and/or cephalometric evidence of maxillo-mandibular hypoplasia or retrusion, the possibility of extending indications to include other types of patients remains unclear, and few studies have been published .

Regarding the maxilla, a wide advancement beyond the traditional cephalometric values could compromise the facial aesthetic. This retrospective study evaluates the results obtained in two groups of patients with abnormal or normal facial patterns, through MMA surgery. The results are discussed and compared with reports in the literature, in particular the indications and motivations for this treatment.

Materials and methods

Between January 2003 and November 2007, a retrospective study of two groups of patients affected by severe or moderate OSAS, with different skeletal patterns, and treated by MMA was carried out. Group I included 11 patients with known severe or moderate OSAS, who had been undergoing treatment with N-CPAP for some time but had not tolerated it well, and who had clinical and cephalometric evidence of dento-facial anomalies ( Table 1 ): SNA angle 78° or less or SNA > 78°, but with SNB angle < 65° and severe mandibular deformity with skeletal class II malocclusion. Group II included 11 patients with known severe or moderate OSAS, who had been undergoing treatment with N-CPAP for some time but had not tolerated it well, but who had cephalometric, occlusal and aesthetic characteristics within the normal range ( Table 2 ): SNA angle > 80° and class I occlusion. Other inclusion criteria were: apnea hypopnea index (AHI) > 20, and Epworth sleepiness scale (ESS) > 10 in both groups.

Table 1
Analytical results for group I.
Patients BMI SNA SNB PAS AHI Epworth S.S. Aesthetic satisfaction
Age Sex Pre Post Pre Post Pre Post Pre Post Pre Post
1 56 M 24.6 74 79 64 70 4 13 46 6 16 0 C
2 63 M 31 85 88 64 68 3 10 48 9 17 2 C
3 45 M 29.6 71 74 65 66 5 10 71 18 14 1 B
4 29 M 22.2 74 83 68 72 8 11 31 3 13 0 C
5 26 M 24 73 89 79 85 8 14 70 1 16 0 C
6 49 F 17.5 80 83 65 75 0 7 62 4 15 2 C
7 42 F 28.7 77 87 71 80 3 9 75 11 14 2 B
8 51 M 25 80 88 65 80 5 9 72 10 20 2 B
9 48 M 26 75 88 74 80 5 19 75 7 18 1 B
10 42 M 24.1 78 84 71 80 4 9 51 5 12 0 B
11 37 M 26.9 73 75 69 74 4 11 36 3 13 0 C

Table 2
Analytical results for group II.
Patients BMI SNA SNB PAS AHI Epworth S.S. Aesthetic satisfaction
Age Sex Pre Post Pre Post Pre Post Pre Post Pre Post
1 38 F 31.2 83 90 74 81 3 11 78 7 18 1 B
2 45 M 23.5 83 86 78 83 0 7 60 12 11 1 A
3 50 M 30.6 80 84 76 81 3 11 38 4 12 2 A
4 47 M 27.1 82 90 81 88 4 13 64 6 11 0 B
5 62 M 27.1 80 85 80 84 4 10 60 15 13 1 A
6 54 M 31 82 91 82 88 5 12 71 10 12 2 A
7 43 M 28 82 89 75 79 5 12 34 10 12 0 B
8 30 M 23.4 84 90 82 87 3 8 24 1 12 0 B
9 45 M 25.1 82 84 77 82 6 11 29 10 11 3 B
10 46 M 26 80 88 77 84 3 13 26 1 14 0 A
11 40 M 27.7 83 90 80 88 5 12 73 8 12 0 C
Only gold members can continue reading. Log In or Register to continue

Feb 8, 2018 | Posted by in Oral and Maxillofacial Surgery | Comments Off on Effectiveness of maxillo-mandibular advancement in obstructive sleep apnea patients with and without skeletal anomalies
Premium Wordpress Themes by UFO Themes