RELATIONSHIP OF GINGIVAL CALCULUS AND BLEEDING ON PROBING IN CPITN CODE-2 SEXTANTS

The aims of this study were twofold: firstly, to evaluate the relation ship of supra- or subgingival calculus and bleeding on probing (BOP) i n sextants coded 2 in the Community Periodontal Index of Treatment Nee ds (CPITN); and secondly, to compare the differences in four investiga tions in Taiwan, Hong Kong, Japan and Norway. In a national survey, a total of 2658 Chinese dentate adults were examined by using modified C PITN in the Taiwan area from 1985 to 1987. Sextants given Code 2 were divided into four subclassifications: supragingival calculus with blee ding (I+), supragingival calculus without bleeding (I-), subgingival c alculus with bleeding (II+) and subgingival calculus without bleeding (II-). The results showed that of the 9394 sextants given Code 2, the highest percentage (70%) were characterized by the presence of subging ival calculus with bleeding and the lowest percentage (4%) by supragin gival calculus with bleeding. The ratio of sextants coded 2 with only supragingival calculus versus subgingival was 1:6.2. The bleeding to n onbleeding ratio of sextants coded 2 in this study was similar to the Hong Kong study. However, differences among Taiwan, Japan and Norway w ere found. The results indicated that sextants with subgingival calcul us had a higher tendency to BOP, with a ratio of 4:1. Those with supra gingival calculus had a ratio of 3:7. We conclude therefore, that it i s essential to scale teeth to remove subgingival calculus for determin ation of the necessity of periodontal treatment.