Could Dental Chair Position–Dependent Mandibular Dynamics Influence Craniocervical Configuration and Sleep-Related Upper-Airway Patency?

Dental occlusion is commonly assessed and adjusted with the patient in a reclined or supine dental-chair position, whereas most daily oral functions occur in upright positions. This hypothesis article proposes that static maximum intercuspation and the dynamic pathway by which the mandible reaches that position should be considered separately. In a subset of individuals exhibiting reproducible posture-dependent mandibular responses, dental-chair or head position may modify mandibular closing trajectories, initial contacts, and occlusal force distribution. The proposed model does not assume that the mandible universally moves posteriorly in the supine position, nor that occlusal changes directly cause obstructive sleep apnea (OSA). Instead, it presents a threshold-modifier model in which mandibular configuration may interact with craniocervical posture, upper-airway anatomy, neuromuscular compensation, and sleep state in physiologically susceptible individuals. Existing evidence supports individual links within this model, including posture-dependent mandibular dynamics, mandibular influences on tongue-hyoid and pharyngeal anatomy, effects of craniocervical position on upper-airway collapsibility, and sleep-related reductions in neuromuscular compensation. However, the complete pathway linking dental-chair position, mandibular dynamics, craniocervical configuration, and sleep-related upper-airway stability has not been directly tested. A prospective randomized within-subject physiological study is proposed to evaluate reproducible mandibular response phenotypes, upper-airway mechanics, and sleep-related respiratory outcomes.