Sleeping Tongue Posture and Its Relationship to Craniofacial Morphology

Introduction: There exists good consensus in the literature supporting the notion that resting tongue posture is an important factor in dental arch development and maintenance as well as airway control. What has yet to be quantitatively measured is the duration of time that a subconscious, resting tongue posture is maintained and whether such posture differs among various craniofacial morphologies. Quantifiable measurements might allow for prediction of tongue-posture-related problems specific to certain facial types. Purpose: The objective of this study was to record sleeping tongue posture over time in 27 subjects and to compare findings with craniofacial morphology determined by cephalometric and model analysis. Methods: A sample of 27 subjects (11 female, 16 male) slept for three nights each while wearing an intraoral, tongue-posture-monitoring device. Tongue posture indices (TPI) were calculated for each night and compared with vertical and transverse skeletal measurements taken from a lateral cephalograph and plaster study models. Results: Nonparametric correlations demonstrated that average TPI is significantly and inversely correlated with palatal height, ratio of palatal height/palatal width, and lower face height (p \u3c .002, .001, 028 respectively). Independent samples median tests showed that TPI was significantly lower for subjects that snore, breathe through their mouth and nose, and sleep on their back (p \u3c .037, .057, .096 respectively). Conclusions: Variability in sleeping tongue posture exists between people of differing facial morphologies. Sleeping tongue posture also appears to vary depending on sleeping position, breathing modality, and tendency to snore