Effects of mandibular setback with or without maxillary advancement osteotomies on pharyngeal airways: An overview of systematic reviews

Abstract

BackgroundMandibular setback osteotomies potentially lead to narrowing of the pharyngeal airways, subsequently resulting in post-surgical obstructive sleep apnea (OSA).ObjectiveTo summarize current evidence from systematic reviews that has evaluated pharyngeal airway changes after mandibular setback with or without concomitant upper jaw osteotomies.MethodologyPubMed, EMBASE, Web of Science, and Cochrane Library databases were searched with no restriction of language or date. Systematic reviews studying changes in pharyngeal airway dimensions and respiratory parameters after mandibular setback with or without concomitant upper jaw osteotomies have been identified, screened for eligibility, included and analyzed in this study.ResultsSix systematic reviews have been included. While isolated mandibular setback osteotomies result in reduced oropharyngeal airway dimensions, the reduction is lesser in cases with concomitant upper jaw osteotomies. Only scarce evidence exists currently to what happens to naso- and hypo-pharyngeal airways. There is no evidence for post-surgical OSA, even though some studies reported reduced respiratory parameters after single-jaw mandibular setback with or without concomitant upper jaw osteotomies.ConclusionAlthough mandibular setback osteotomies reduce pharyngeal airway dimensions, evidence confirming post-surgical OSA was not found. Nevertheless, potential post-surgical OSA should be taken into serious consideration during the treatment planning of particular orthognathic cases. As moderate evidence exists that double-jaw surgeries lead to less compromised post-surgical pharyngeal airways, they should be considered as the method of choice especially in cases with severe dentoskeletal Class III deformity.Study registrationPROSPERO (registration number: CRD42016046484).

Silent Changes in Sleep Quality Following Mandibular Setback Surgery in Patients with Skeletal Class III Malocclusion: A Prospective Study

“…Currently, it is widely accepted that a relative reduction of the pharyngeal airway space (PAS) could be resulted from mandibular setback. Although some papers have reported patients who were diagnosed with mild OSA after MSS 1,2 , there is no evidence for postoperative OSA 3–5 . However, many authors have recommended simultaneous double jaw surgery consisting of maxillary advancement and mandibular setback for severe class III patients not only to reduce the amount of mandibular setback, but also to lower the risk of pharyngeal airway compromise because of the possibility of postoperative OSA 6–9 .…”

Existence of a Neutral-Impact Maxillo-Mandibular Displacement on Upper Airways Morphology

“…Notably, one case reported a ∆area increase of 50% at the level of the nasopharynx following MAMS (mandibular setback: −3.68 mm; maxillary advancement: +7.2 mm). It is reasonable to hypothesize that a higher degree of upper maxillary forward translation counteracts the reduction in surface area that mandibular setback may induce, as previously reported [ 21 , 22 ].…”

Why most patients do not exhibit obstructive sleep apnea after mandibular setback surgery?

“…Although airway narrowing was improved after surgery, the pharyngeal airway volume remained lower compared with the preoperative airway volume. The comparative studies and meta-analysis of mandibular setback surgery have shown that maxillary advancement or maxillary posterior impaction would be able to attenuate the narrowing of the airway [2,27]. The AHI is defined as the total number of apneas and hypopneas per hour of sleep by polysomnography.…”

“…Interestingly, even for an underweight patient with a normal AHI (BMI of 18.9, preoperative AHI of 0.2), the AHI was increased to 7 [4]. However, a recent review of previously published systematic reviews suggested that although the development of postsurgical OSA has been reported, there is no clear evidence that confirms a direct cause-and-effect relationship between mandibular setback surgery and OSA development [27]. For patients with severe mandibular prognathism or patients with potential for OSA development, two-jaw surgery should be strongly considered [34].…”