Relationship of tooth grinding pattern during sleep bruxism and dental status.

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.