Effects of sleep bruxism on functional and occlusal parameters: a prospective controlled investigation

This study was conducted to verify the results of a preceding retrospective pilot study by means of a prospective controlled investigation including a larger sample size. Therefore, the aim of this clinical investigation was to analyze the relationship between sleep bruxism and several functional and occlusal parameters. The null hypothesis of this study was that there would be no differences among sleep bruxism subjects and non-sleep bruxism controls regarding several functional and occlusal parameters. Fifty-eight sleep bruxism subjects and 31 controls participated in this study. The diagnosis sleep bruxism was based on clinical criteria of the American Academy of Sleep Medicine. Sixteen functional and occlusal parameters were recorded clinically or from dental study casts. Similar to the recently published retrospective pilot study, with a mean slide of 0.77 mm (s.d., 0.69 mm) in the sleep bruxism group and a mean slide of 0.4 mm (s.d., 0.57 mm) in the control group, the evaluation of the mean comparison between the two groups demonstrated a larger slide from centric occlusion to maximum intercuspation in sleep bruxism subjects (Mann–Whitney U-test; P=0.008). However, following Bonferroni adjustment, none of the 16 occlusal and functional variables differed significantly between the sleep bruxism subjects and the non-sleep bruxism controls. The present study shows that the occlusal and functional parameters evaluated do not differ between sleep bruxism subjects and non-sleep bruxism subjects. However, as the literature reveals a possible association between bruxism and certain subgroups of temporomandibular disorders, it appears advisable to incorporate the individual adaptive capacity of the stomatognathic system into future investigations. People who grind their teeth in sleep do not necessarily have unusual dental physiology, research from Germany shows. Michelle Ommerborn and co-workers at Heinrich-Heine University, Düsseldorf, in collaboration with an orthodontic dental practice in Langenfeld, Germany, have completed a study involving 58 patients with known sleep bruxism (grinding), and 31 control patients with no grinding symptoms. Following up on a previous pilot study, the team focused on 16 different aspects of dental physiology, from overbite of canines to the maximum left and right movement of the mandible. The team discovered that teeth grinders have a more pronounced slide from first contact of teeth on biting (centric occlusion) to full closure of all teeth (maximum intercuspation). However, none of the other parameters were found to be statistically significant, contradicting the earlier pilot study.