[Obstructive Sleep disordered breathing, sleep bruxism and periodontal diseases]

Sleep disordered breathing (SDB) may be associated with sleep bruxism and periodontal diseases. Through a review of the current literature, this article aims to describe the characteristics of sleep bruxism and its relationship with SDB as well as the current evidence supporting an association between periodontal diseases and SDB. Sleep bruxism is characterized by muscle clenching and tooth grinding during sleep, typically during N2 sleep stage and in association with micro-arousals. The probability of observing sleep bruxism is almost 4 times higher in the presence of SDB, with a close temporal relationship between the episode of upper airway obstruction or oxygen desaturation and the episode of bruxism, which most often occurs in the 0-10 seconds following the obstruction. These findings support the hypothesis that sleep bruxism is triggered by SDB and may have a "protective" role being a muscular activity that helps restore the permeability of the upper airways. On the other hand, SDB have been linked to periodontal diseases. Periodontal diseases are inflammatory and dysbiotic disorders that can have a negative impact on oral health (leading to the destruction of the periodontium and tooth loss) and on general health. Recently, it has been observed that SDB patients have a 1.6 to 4-fold higher risk of having or developing severe periodontitis, suggesting that SDB may be a new risk factor for periodontal diseases. Dentists, who are part of the team of sleep medicine specialists, have a key role in the detection, prevention and treatment of SDB and their relationship with sleep bruxism and periodontal diseases.