Correlation of interdental and interradicular bone loss in patients with chronic periodontitis: a clinical and radiographic study.

OBJECTIVE The aim of this study was to investigate the correlation between interdental and interradicular bone loss and clinical parameters in patients with chronic periodontitis. MATERIALS AND METHODS One hundred-twenty intraoral periapical radiographs of first molars were obtained from patients with chronic periodontitis and were digitalized to record height and width of the bone defect in the interdental and interradicular region (furcation) and bone defect angle in the interdental region in vertical defects. Pocket depth (PD) and clinical attachment loss (CAL) was recorded at three sites. The data was divided into groups according to the pocket depth at each site. One-way ANOVA was used to compare three different pocket depths with respect to CAL, height and width at a particular site. This was followed by Tukeys HSD post hoc tests to know the significant difference between two groups of pocket depths. Lastly Karl Pearsson's co-efficient method was applied to find out the relationship among CAL, height and width for the particular site. RESULTS When the pocket depth groups were compared for CAL, height and width of the defect at all three maxillary and mandibular sites, the results were statistically significant. In maxillary molars, a radiographic bone defect height ranging from 3.4-7.1 mm at the mesiobuccal site and 3.6-7.2 mm at the distobuccal site was associated with 1.2-3.5 mm defect height in the interdental region. In mandibular molars, a radiographic bone defect height ranging from 2.9-7.0 mm at the mesiobuccal site and 3.2-6.8 mm at the distobuccal site was associated with 1.2-3.6 mm defect height in the interdental region. The mean bone defect angle was 36.3 ± 16.5 degrees. CONCLUSION Treatment of interdental bone loss can prevent further bone loss in the interradicular region. Radiographic measurements combined with clinical findings can be useful for periodontal risk assessment.