Effect of Tooth Brushing Instruction on Prevention of Tooth Loss in Factory Workers.

Individual tooth brushing instruction was given once a year to male workers voluntarily selected in 5 factories in Osaka from 1981 to 1989.To evaluate the effect of instruction, participants were divided into two groups. Group A was 265 males who were given the instruction twice or more. Group B was 198 males who were given the instruction only once. Changes in oral health conditions were compared in these groups.Statistically significant differences were observed in rate of persons with the change of debris score and frequency of tooth brushing between the two groups. The average number of teeth lost per year was 0.042 in group A and 0.078 in group B. The mortality of teeth was significantly lower in group A than in group B. These results show how tooth brushig instruction to the factory workers can improve oral health and prevent tooth loss.