“Silent” Sleep Apnea in Dentofacial Deformities and Prevalence of Daytime Sleepiness After Orthognathic and Intranasal Surgery

Abstract

The purposes of this study were to determine the occurrence of undiagnosed "silent" obstructive sleep apnea (OSA) in dentofacial deformity (DFD) patients at initial surgical presentation and to report on the level of daytime sleepiness in DFD patients with OSA and chronic obstructive nasal breathing (CONB) after undergoing bimaxillary, chin, and intranasal surgery. A retrospective cohort study of patients with a bimaxillary DFD and CONB was implemented. Patients were divided into those with no OSA (group I) and those with OSA (group II). Group II was further subdivided into patients referred with polysomnogram (PSG)-confirmed OSA (group IIa) and those with a diagnosis of OSA only after surgical consultation, airway evaluation, and a positive PSG (group IIb). Group II patients were analyzed at a minimum of 1year after surgery (range, 1 to 10years) for daytime sleepiness with the Epworth Sleepiness Scale.Patients with postoperative excessive daytime sleepiness were assessed for risk factors and continued need for OSA treatment. Patients in group II were studied to determine which DFD patterns were most associated with OSA. We compared the prevalence of OSA between our study population and the general population. Two hundred sixty-two patients met the inclusion criteria. Of these, 23% (60 of 262) had PSG-confirmed OSA (group II). This rate was much higher than that found in the general population. Of the patients, 7% (19 of 262) were known to have OSA at initial surgical consultation (group IIa). An additional 16% (41 of 262) were later confirmed by PSG to have OSA (group IIb). Patients with primary mandibular deficiency and short face DFDs were most likely to have OSA (P<.001 and P=.001, respectively).In group II, 91% (55 of 60) rated their daytime sleepiness as "not sleepy" at a minimum of 1year after surgery. A significant association was found between group II patients with postoperative excessive daytime sleepiness ("sleepy" or "very sleepy") and a preoperative body mass index category of overweight (P=.026). Our study found silent OSA to be frequent in the DFD population. The prevalence of OSA in DFD patients exceeded that estimated in the general population, with retrusive jaw patterns most affected. In DFD patients also presenting with OSA and CONB, we confirmed low levels of daytime sleepiness long-term after simultaneous bimaxillary orthognathic, chin, and intranasal surgery.