5-year results of a longitudinal study of early periodontitis in 14- to 19-year-old adolescents.

This 5-year longitudinal study monitored 167 subjects at ages 14.3, 16.0 and 19.6 years. The aims were (1) to determine loss of attachment greater than or equal to 1 mm in the study group over the 5-year period; (2) to relate baseline levels of oral deposits and gingivitis to the 5-year increment of loss of attachment; (3) to determine whether subjects who had developed loss of attachment greater than or equal to 1 mm by age 16 years were more susceptible to further development of loss of attachment; (4) to evaluate loss of attachment indices. Loss of attachment, plaque, subgingival calculus, gingival bleeding and gingival colour change were measured. At baseline, 3% of subjects had loss of attachment greater than or equal to 1 mm and less than 1% of sites were involved. By age 19 years, 77% had loss of attachment greater than or equal to 1 mm, and 31% of sites were affected. There was a significant correlation between the presence of subgingival calculus at baseline and the 5-year increment of loss of attachment (Pearson's r = 0.26 p less than 0.001). Subjects who had developed loss of attachment by age 16 years still had significantly more sites affected at the more severe 2 mm level 3 years later than their peers (p less than 0.05). The results suggest that a flexible approach is needed in selecting indices of loss of attachment for epidemiological investigations.