Buccal mucosa ridging and tongue indentation: incidence and associated factors

Buccal mucosa ridging and tongue indentation have been considered as one of the visible and reliable signs of bruxism. However, there have not been any reports justifying this relationship scientifically. Moreover, there have not been any studies reporting specific procedures to assess them. Thus, the purpose of the present study was to determine the clinical incidence of buccal mucosa ridging and tongue indentation and assess the possible relationship between certain factors that can influence their occurrence. A total of 244 (178 males and 66 females) dentulous adults from 20 to 59 years of age, who were employees at the Bank of Yokohama, were randomly selected. At first, the buccal mucosa ridging and tongue indentation were classified into three groups based in their intensity: none, mild, and severe. The incidence of both conditions in the different age groups, as well as the incidence by gender was evaluated. Furthermore, the possible relationships between buccal mucosa ridging and tongue indentation and age, gender, clenching awareness, grinding awareness, headache, neck stiffness, vertical dimension, temporomandibular joint (TMJ) pain to palpation, masticatory muscle tenderness to palpation, and the presence of premature contacts were evaluated using the chi-square test. A positive relationship was found between the occurrence of buccal mucosa ridging and tongue indentation and gender (p < 0.01); both conditions were observed more frequently in females than in males. A positive relationship was also found to age; the group between 20-29 years old showed the highest incidence. The vertical dimension had a positive relationship with the occurrence of both buccal mucosa ridging and tongue indentation. Other factors evaluated did not show any correlation.