Effect of nonsurgical periodontal therapy (VIII). Probing attachment changes related to clinical characteristics.

Individual sites with gain and loss of probing attachment were identified amongst 1688 proximal sites in non-molar teeth from 49 patients monitored for 24 months following oral hygiene instruction and root debridement. The distribution of sites with gain and loss of probing attachment was studied within each of the 49 subjects, for each of the 10 different tooth types treated, for teeth with and without root canal fillings, for mesial and distal surfaces, and for surfaces with and without the presence of root concavity/furcation involvement. Similarly, sites with gain and loss were related to the following measurements of the severity of the initial lesion: initial probing depth, radiographic bone score, depth of radiographic intraosseous defect, and radiographically widened periodontal ligament. The analyses indicated that subjects with a higher proportion of sites with probing attachment gain tended to have a lower proportion of sites with probing attachment loss. Sites with deep initial probing depth demonstrated a high incidence of gain and a low incidence of loss of probing attachment. All other investigated characteristics showed weak or no association with probing attachment change following therapy. This report indicates that the 24-month outcome of plaque control and root debridement in proximal surfaces of non-molar teeth is not compromised by the severity of the initial soft tissue or bony lesion.