Three-Dimensional Measurement of Bone Loss at Implants in Patients With Periodontal Disease

Background: The aim of this prospective study is to evaluate the three-dimensional marginal bone level around implants 5 to 15 years after loading in partially edentulous patients treated for generalized chronic periodontitis (GCP) and generalized aggressive periodontitis (GAgP). Methods: Seventeen patients with GCP and 17 patients with GAgP were treated with a total of 119 implants. Patients were examined clinically on a 3-month recall schedule after insertion of the superstructure, and radiographs were taken at fixed intervals. At the end of the observation period, cone-beam computed tomography was used for the analysis of the circumferential three-dimensional bone level (mesial, distal, buccal, and lingual/palatal) and determination of keratinized mucosa thickness (KMT). Results: In both groups, a significant bone loss at implants was observed buccally (GAgP group: 4.49 +/- 2.93 mm; GCP group: 3.57 +/- 2.94 mm) with significantly more average bone loss in patients with GAgP (3.00 +/- 1.67 mm) compared to in patients with GCP (2.45 +/- 1.08 mm). The lowest values for KMT in both groups were found in the anterior mandible (GAgP group: 0.99 +/- 1.13 mm; GCP group: 0.82 +/- 0.91 mm). There were significant correlations between clinical parameters and bone loss in mandibles of patients with GAgP. Conclusions: The lowest value for KMT in both groups was found in the mandible. Bone loss was observed buccally and was more pronounced in patients with GAgP, with a significant correlation with keratinized mucosa and increased inflammation. J Periodontol 2011;82:689-699.