Long-term changes in marginal and periapical periodontal conditions in patients with fixed prostheses: a radiographic...

Patients treated at a prosthodontic department during the years 1968-73 with fixed restorations (at least five units) were followed up in 1991-92. The aim of the present study was to compare marginal and periapical periodontal conditions on radiographs from 1968-73 and 1991-92 and relate the changes to the results of the prosthodontic treatment. In the group in which the restorations remained unchanged, 90% of the abutments that were not root filled and showed no periapical radiolucency when the restorations were placed, were still not root filled and showed no periapical radiolucency at the follow-up examination. The corresponding figure for the group in which the restorations had been replaced was only 69%. The changes in marginal bone levels also differed between the groups. In the group with remaining restorations, 66% of the surfaces were given the same score on a five-point scale both in 1968-73 and in 1991-92. In the other group, only 54% were scored the same on both occasions. Thus, unfavourable changes in both periapical and marginal periodontal conditions were associated with poorer results for the fixed restorations.