DENTAL EROSION AND BRUXISM - A TOOTH WEAR ANALYSIS FROM SOUTH EAST QUEENSLAND

Tooth-tissue loss from erosion and attrition from bruxism were associa ted findings in 104 patients with excessive toothwear from South East Queensland. Approximately one-third of these subjects had been given a diagnosis of bruxism prior to referral. After a structured interview and clinical examination, the prevailing diagnosis was tooth erosion a ssociated with occupational or sports-related dehydration, and one-thi rd of the subjects were provisionally classified as bruxers. Eight ite ms of clinical history and examination, designed to differentiate brux ers from non-bruxers, were analysed retrospectively from their records . These clinical items, by which the diagnosis of bruxism might be mad e, segregated the subjects into three groups of equal size, 'bruxers, possible bruxers and non-bruxers,' by a notional score for bruxism. Th e presence of occlusal attrition or erosion on the sextants of the den titions was determined by scanning electron microscopic criteria on ep oxy resin dental casts. The incidence of attrition versus erosion was compared between the three groups. The hypothesis was that attrition w ould be found on more sextants of bruxers than non-bruxers. Erosion pr edominated in virtually all sextants in all three groups, to the virtu al exclusion of attrition in the molar sextants. The exception was the mandibular anterior sextant, where more sextants in bruxers were affe cted by attrition. Thus extrinsic or intrinsic acid erosion was strong ly associated with occlusal tooth wear found in bruxers. Conversely, t ooth-wear patterns were unreliable indicators of a bruxing habit, for attrition alone was often found on acid-exposed teeth. Thus, even if a patient is suspected of having bruxism, dental erosion is more likely the cause of tooth-tissue loss than attrition, especially in the dehy drating environment of South East Queensland.