Periodontal loser sites in untreated adult subjects.

Subjects in age groups between 20 and 79 years were recruited for a study on the effect of different modalities of periodontal therapy. A baseline examination included assessments of plaque, gingivitis, probing pocket depth and probing attachment level. The subjects received no periodontal therapy for 2 years but were recalled for re-examination after 1 and 2 years. The results from the baseline examination and the overall changes which occurred in the sample during the 2 years have been reported previously. The present study describes some characteristics of subjects and sites that lost probing attachment of 3 mm or more during the course of the 24 months of monitoring. 161 of the 265 subjects who returned for both re-examinations had no change of the attachment level at any site that amounted to 3 mm or more. Of the 104 subjects that showed deterioration, at or above this level, the majority exhibited disease activity either during the 1st or the 2nd year of monitoring. Only 20 subjects showed disease activity during both year 1 and year 2. In addition, 70% of the sites that deteriorated (loser sites) occurred in 12% of the subjects. Loser sites were most frequently detected in older subjects and at molar sites. Most of the loser sites occurred at interproximal surfaces and were most numerous at surfaces with initially advanced loss of attachment.