Tooth wear is a condition defined as loss of substance from tooth hard tissue in response to a mechanical, chemical, or a combination of both responses, and may not be involved with dental caries [1]. This process should consider two parameters, mechanical (attrition and abrasion) and chemical wear (erosion) [2,3]. Recent epidemiological studies have shown that tooth wear is common and increases with age in both primary and permanent dentitions [3], [4], [5].

The global tooth wear prevalence remains unknown [6]. A wide range of tooth wear prevalence in permanent dentition worldwide has been reported from 26.9 to 90.0% [4,5,7], with severe tooth wear present in 25% of a young population [8]. This variation can be attributed to the different diets and lifestyles of numerous populations and the application of various indices to assess tooth wear [1,2,9]. The severity of tooth wear differs among various studies; for example, erosion was confined to enamel in most cases (>80%) whereas other studies showed dentine involvement in 21 to 48%, with the occurrence of tooth wear with pulp involvement being quite rare (<1%) [10].

There is a concern that tooth wear can be considered a growing oral health problem [11]. There is an important global decrease in tooth loss with people maintaining their teeth for longer periods, and consequently, these teeth are steadily exposed until elderly hood. Some risk factors have been related to increasing wear e.g. dietary habits (mainly the high consumption of acidic products) [12], gastroesophageal reflux [13,14], frequency of brushing [15], malocclusion [16], educational status [17], family income [18], gender [19], and anxiety [20]. In addition, whereas bruxism should not be considered solely a risk factor for tooth erosion, it has been associated with mechanical wear and increases if associated with other risk factors [15,21]. While these factors can be more easily identified during dental consultation, they cannot alone be the triggering factor for tooth wear (erosion). Thus, assessing risk factors that may be associated with tooth wear is necessary.

Most studies evaluating the prevalence of tooth wear have presented a cross-sectional design, with few studies using a longitudinal approach [5]. Cohort studies could contribute to a more precise identification of risk factors during the lifetime, and which factors could influence the presence of tooth wear in its course [22]. This study aimed to investigate the prevalence of tooth wear and associated factors in adults from the 1982 Pelotas Birth Cohort.