Comparison of various modalities of "simple" periodontal therapy on oral cleanliness and bleeding.

550 Chinese employees of both sexes aged 25-44 from an industrial organisation participated in a 16-month longitudinal study. Subjects were divided into 4 groups: an oral hygiene group (group A), a scaling group (group B), an oral hygiene + scaling group (group C) and a control (group D). The experimental subjects were examined at baseline, 2 weeks, 4 months, 10 months and 16 months. After 10 months, group A received scaling while group B was given oral hygiene instruction for the 1st time. The control group did not receive any treatment until completion of the programme. At 16 months, all 3 experimental groups had significantly lower plaque and bleeding scores than the control. The plaque and bleeding levels of the experimental groups were lower at all review appointments when compared with baseline. Some variations in the clinical parameters were found between groups at 2 weeks, 4 months and 10 months. The scaling + oral hygiene group showed the best response. Although a proportion of subjects showed a substantial improvement in bleeding scores following scaling, the significant resource implications in providing such treatment has to be considered in planning community health programmes to promote periodontal health, wherein oral hygiene education must still have the highest priority.