Date Published: July 27, 2017
Publisher: Public Library of Science
Author(s): Su Keng Tan, Wai Keung Leung, Alexander Tin Hong Tang, Roger A. Zwahlen, Soroush Zaghi.
Mandibular advancement surgery may positively affect pharyngeal airways and therefore potentially beneficial to obstructive sleep apnea (OSA).
To collect evidence from published systematic reviews that have evaluated pharyngeal airway changes related to mandibular advancement with or without maxillary procedures.
PubMed, EMBASE, Web of Science, and Cochrane Library were searched without limiting language or timeline. Eligible systematic reviews evaluating changes in pharyngeal airway dimensions and respiratory parameters after mandibular advancement with or without maxillary surgery were identified and included.
This overview has included eleven systematic reviews. Maxillomandibular advancement (MMA) increases linear, cross-sectional plane and volumetric measurements of pharyngeal airways significantly (p<0.0001), while reducing the apnea-hypopnea index (AHI) and the respiratory disturbance index (RDI) significantly (p<0.0001). Two systematic reviews included primary studies that have evaluated single-jaw mandibular advancement, but did not discuss their effect onto pharyngeal airways. Based on the included primary studies of those systematic reviews, single-jaw mandibular advancement was reported to significantly increase pharyngeal airway dimensions (p<0.05); however, conclusive long-term results were lacking. MMA increases pharyngeal airway dimensions and is beneficial to patients suffering from OSA. However, more evidence is still needed to draw definite conclusion related to the effect of single-jaw mandibular advancement osteotomies on pharyngeal airways.
Pharyngeal airway dimensions are inevitably affected by skeletal jaw movements during orthognathic surgery. Both one-jaw mandibular advancement[1, 2] and two-jaw maxillomandibular advancement (MMA) have been reported to increase pharyngeal airway dimensions. The one-jaw approach is less popular because two-jaw osteotomy provides an overall more balanced post-surgical aesthetic outcome. Furthermore, aside from being used to treat certain dentofacial deformities, two-jaw osteotomies have also been reported to be effective in treating or reducing the severity of obstructive sleep apnea (OSA).
The reporting of this systematic review adheres to the Cochrane’s recommendation on overview of systematic reviews and the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement[20, 21] when relevant. A review protocol was developed and registered with PROSPERO; registration number: CRD42016046489 (https://www.crd.york.ac.uk/prospero/display_record.asp?ID=CRD42016046489).
The here presented overview detected significantly reduced AHI after MMA with a relatively high treatment success rate (>85%) in OSA patients. This is comprehensible and in line with consistently increased post-MMA linear, cross-sectional area and volumetric pharyngeal airway measurements. The minimum CSA is one of the most commonly used airway measurements, and has been associated with the incidence of OSA. A complete pharyngeal airway analysis should include linear, cross-sectional and volumetric analyses[14, 47] on various predefined areas to reveal the actual changes in all dimensions. Unfortunately, most articles did not assess all three aspects together. Additionally, to date, no specific guideline for standard assessment of pharyngeal airway evaluation exists, despite of its importance.
Maxillomandibular advancement (MMA) increases pharyngeal airway dimensions, providing positive post-surgical effects in patients suffering from OSA. However, still more evidence is needed to draw conclusions related to effect of single-jaw mandibular advancement osteotomies on pharyngeal airways.