Factors associated with the incidence of erosive wear in upper incisors and lower first molars: A multifactorial approach

ObjectivesThe aim was to investigate associations between factors and the incidence of erosive wear in lower first molars and upper incisors, and to investigate whether these associations differ between these locations.MethodsThe study sample of this 3-year longitudinal study consisted of 572 children (mean age 11.9 years, SD = 0.9). The permanent dentition was examined for erosive wear according to a modified Lussi-index (1996). Information on biological and behavioural factors was gathered by clinical examinations (at baseline, after 1.5 and 3 years) and by questionnaires (every six months).ResultsThe incidence of erosive wear in upper incisors over 3 years was 22.2%, for lower first molars the incidence was 14.8%. Multivariate logistic regression analysis showed that carbonated soft drink (OR = 1.04) and tooth grinding (OR = 2.93) were positively associated with the incidence of erosive wear in upper incisors and milk (OR = 0.95) and yoghurt products (OR = 0.88) were negatively associated. The incidence of erosive tooth wear in lower first molars was positively associated with alcoholic mixed drink (OR = 1.45) and tooth grinding (OR = 4.00) and was negatively associated with milk (OR = 0.96) and yoghurt products (OR = 0.84). The incidence of erosive wear in lower first molar was lower in girls than in boys (OR = 0.51). t-Tests on the odds ratios of the factors showed that between the two incidence models only the odds ratios of anterior contact significantly differed.ConclusionsIn the present study, except for anterior contact, no substantial differences in risk factors between the incidence of erosive wear in lower first molars and upper incisors were found. This indicates that the aetiology of erosive wear for the two locations is similar.