Decrypting the putative interrelation between sleep bruxism, masticatory muscle pain and sleep breathing disorders: Nosology and the role of hypoxia

This commentary on sleep medicine explores whether the potential relationship between sleep bruxism (SB), masticatory muscle pain (MMP) and sleep breathing disorders (SBDs) contributes to improving the management of co-occurring conditions.The paper is divided into 2 sections: (1) reviewing the debate on SB nosology; and (2) based on the publications from the Martynowicz & Wieckiewicz research group, exploring the role of intermittent hypoxia as a putative mechanism endotype that may link such co-occurrence among individuals for whom characteristics are not yet clear. Disentangling the nosology of sleep bruxism is essential before associating it with other conditions and investigating mechanismsAccording to the consensus from a group of clinical scientists presented in a work-in-progress report, sleep bruxism (SB) is defined as "masticatory muscle activity during sleep that is characterized as rhythmic (phasic) or nonrhythmic (tonic), and is not a movement disorder or a sleep disorder in otherwise healthy individuals". 1Sleep bruxism is currently considered an oro-motor behavior, with central interaction between the cerebral and cardiorespiratory autonomic systems.The specificity of the genetic contribution remains to be confirmed. 22][3] Difficulty with clarifying whether SB is a behavior or a disorder is evident in a series of landmark commentaries; it is due to the gray area between a behavior without consequences and the point at which it becomes harmful. 4Therefore, standardization is required so that firm, evidence-based conclusions could be generalized to clinical practice. 5This is further corroborated by a recent theoretical analysis that does not support classifying SB as a disorder. 6,7The American Academy of Sleep Medicine (AASM) Cite as