Gingival recession: intra-oral distribution and associated factors.

This study assesses the role of poor oral hygiene and forceful toothbrushing as risk factors for recession. As part of a cross-sectional root surface caries study, 298 subjects, 42 to 67 years of age, with at least one exposed root surface, were examined. Since 66% of the root surface exposure and practically all the abrasion was on buccal surfaces, the analyses focused only on the buccal surface. Analysis of variance on subject means for buccal recession showed both calculus and presence of buccal root surfaces with abrasion to be significantly associated with recession after adjusting for age and gender. Root surface abrasion was considered a surrogate variable for forceful brushing. An additional analysis utilized means for each tooth, aggregating across subjects. For each of the 32 tooth types mean buccal recession, percent of exposed root surfaces with abrasion (%ra), and mean debris and calculus scores were calculated. Partial correlation coefficients across tooth types between recession and calculus, adjusting for abrasion, and for recession and abrasion adjusting for calculus, were 0.55. Interpretation of the %ra as a crude measure of forceful brushing is supported by its strong negative correlation across tooth types, with mean debris (r = -0.8) and mean calculus (r = -0.7). Separate analyses on premolars and on molars suggested that recession on premolars may be primarily due to brushing force and on the molars may be primarily due to debris and calculus. The findings suggest that recession is positively associated with percent abrasion (reflecting forceful brushing) and with poor oral hygiene.