Tooth grinding during sleep is thought to be one of the important factors causing oral diseases. However, no evidence is available regarding the relationship between the dental status and tooth contact during sleep bruxism. The purpose of this clinical study was to investigate the relationship between oral diseases and tooth grinding patterns during sleep bruxism. Fifty subjects (21 men and 29 women) were selected. The clinical attachment level, tooth mobility, noncarious cervical lesion (NCL) and hypersensitivity were examined in each tooth. Subjects wore a bruxism-recording device to visualize the grinding pattern during sleep bruxism. The grinding pattern was categorized into laterotrusive grinding (LG) and mediotrusive side grinding (MG). Furthermore, LG was divided into three types: incisor-canine (IC), incisor-canine-premolar (ICP), and incisor-canine-premolar-molar (ICPM) types. The average attachment level and tooth mobility of the ICPM and ICPM+MG types were much more aggravating than those of the IC or ICP types. The NCL encountered in the ICPM type was more aggravating than the other types. The average NCL of the ICPM type was significantly larger than that of the IC (p = 0.01), the ICP (p = 0.05), the ICP+MG (p = 0.05) and the ICPM+MG (p = 0.05) types and MG (p = 0.01). The average hypersensitivity of the ICP type was significantly greater than that of the IC type (p = 0.05). There was a moderate correlation between the attachment level and mobility. It was concluded that grinding patterns during sleep bruxism should be considered as a probable causative factor in the development of dental problems related to clinical attachment level, tooth mobility, NCL, and hypersensitivity, especially the ICPM type and mediotrusive grinding that seems to be the pattern that could more easily deteriorate the dental condition.

The purpose of this study was to investigate the relationship between tooth grinding pattern during sleep bruxism and temporomandibular joint (TMJ) status based on condylar movement. Fifty subjects (21 males and 29 females) wore a bruxism recording device, BruxChecker, to record their grinding pattern during sleep bruxism. The grinding pattern was categorized into laterotrusive grinding (LG) and mediotrusive side grinding (MG). Furthermore, LG was divided into three types; incisor-canine (IC), incisor-canine-premolar (ICP) and incisor-canine-premolar-molar (ICPM) type. Condylar movements were also recorded using computer-aided axiograph to evaluate the signs of TMJ hypermobility. The average maximum separation distance of excursion and incursion and the average maximum condylar lateral deviation during protrusion/retrusion and open/close movements in the ICPM type and the ICPM+MG type were larger than those of the IC and ICP types. While reconstructing the occlusion, it is important to take into consideration the presence of bruxing patterns of the ICPM type and mediotrusive side grinding.

Purpose: The aim of the present study was to investigate whether there is any association between occlusal contact patterns during sleep bruxism and signs of temporomandibular disorders (TMD).Materials and methods: The association of occlusion pattern and symptoms of TMD was assessed in 240 Japanese participants. Participants completed a questionnaire to report pain and other symptoms regarding TMD and their selfawareness of sleep bruxism. A simple device (BruxChecker) custom fitted to each participant was applied to evaluate the occlusal contact pattern during sleep. Condylograph was also applied to examine the function of temporomandibular joint (TMJ).Results: Participants with a major increment in the mediotrusive side occlusal contact areas on BruxChecker reported significant impact on the high prevalence of TMD signs and self-awareness of sleep bruxism.Conclusion: The positive relationship between a certain classification of occlusal grinding during sleep bruxism and signs of TMD constitutes a key point to consider the possible role of occlusal factors during sleeping as risk indicators in the genesis of TMD.