Fig. (2) The severity of obstructive sleep apnea (OSA) is not associated with the presence of with sleep-related bruxism or nocturnal GERD in patients with OSA. The mean and standard error of the mean of the apnea-hypopnea index (A, C) and lowest oxygen saturation (B, D) are shown for patients with (solid box, solid line) and without (open box, dashed line) bruxism (A, B) and GERD (C, D).