Degree of correlation between two periodontal indices in a rural Croatian population

To compare the periodontal status of patients measured by two indices, the Community Periodontal Index (CPI) and the Loss of Attachment Index (LA).

The CPI and LA index scores were determined for a sample of 367 adult subjects (1,535 dentate sextants) aged 15-65 years from two rural areas in Croatia and analysed according to subject, sextant and jaw.

Partial correlation between the CPI and LA indices was found. Cumulative for all age groups, sextants with a CPI code 0, 1 and 2 most often appeared with a LA 0-3mm. Shallow pocket sextants (4-5mm) in 64.04% also correlated with the loss of attachment values 4-5mm. In deep pocket sextants (6-8 mm), a deviation from expectations was found as they appeared more often with a LA 9-11 mm designation (46.24%), rather than with an LA 6-8mm (34.41%) score. Very similar results were found between distribution per sextant, person and jaw in CPI codes 2, 3, 4 and cumulatively.

CPI itself is not sufficient for periodontal status assessment, especially for the 35-44 years of age, and even more so for the 65+ group, also for the CPI code 4 in all ages.