Longitudinal study of untreated periodontitis. (I). Clinical findings

Abstract
The principal aim of this study was to investigate the use of certain clinical and microbiological criteria to predict periodontal breakdown during a 1-year period. A further aim was to establish whether the act of collecting subgingival plaque samples periodically throughout the observation period would have any effect on the clinical or microbiological variables. Only the clinical data is presented in this paper. The study population comprised 11 volunteers (aged 32-51 years) with persistent advanced periodontitis and inadequate plaque control in spite of a previous intensive course of hygiene therapy. From the left jaw quadrants, 89 teeth were selected, yielding 148 bleeding pockets of 4 mm depth or more. From the right jaw quadrants, 74 teeth were selected, yielding 117 bleeding pockets of 4 mm depth or more. All subjects were examined on 7 occasions at 2-monthly intervals when plaque index scores, dichotomous measurements of gingival redness, pocket depths and attachment levels were recorded. Bacteriological sampling was carried out at each visit for each site only in the left jaw quadrants while the right jaw quadrants were sampled only at the first and last visits. During the study, no subgingival instrumentation was performed, except at 3 sites which exhibited loss of attachment of 3 mm. These teeth were withdrawn from the study for ethical reasons. At the completion of the study, the sequential changes in probing attachment level at each site were subjected to regression analysis to determine the direction and extent of attachment change which had taken place at each site. Further analysis revealed that neither the plaque index scores, the presence of gingival redness nor the pocket depth measurements could be used in a predictive capacity with respect to attachment loss. Comparison of right and left jaw quadrants showed that the act of sampling at 2-monthly intervals had no effect on any of the variables studied.