A comparison of fractal dimension values of peri-implant bone and healthy contralateral side using panoramic radiographs

Abstract

Context: Trabecular bone around dental implants has been rarely evaluated by means of fractal analysis. Aims: The aim was to assess fractal dimension (FD) values of peri-implant bone 12 months after implant installation and to compare these FD values with those of healthy control sites on the contralateral side of the implant area. Materials and Methods: Panoramic radiographs from 29 patients with 29 mandibular implants functioning for 12 months were analyzed. Radiographs were digitized at 300 dpi with 256 grey levels. Healthy trabecular bone from the corresponding contralateral implant-free area was referred as control site. Three region of interests (ROIs) from mesial, distal and apical areas were selected for each implant and each control site. The FD from peri-implant and control ROIs were calculated by means of box-counting method. Statistical analysis was performed using two-way ANOVA with repeated measure on one factor. The independent variable included a between-subjects variable, the site and within-subject variable, repeated measures of ROI. An alpha level of 0.05 was utilized. Results: Mean FD for apical, mesial and distal peri-implant areas were 1.220, 1.222 and 1.226 respectively while the corresponding results were 1.198, 1.183 and 1.202 for control sites. There was not a significant main effect between the FD values of implant and control sides (P = 0.332). Similarly, result of the main effect of ROI (apical, mesial, distal) on FD values was not statistically significant (P = 0.632). Conclusions: Fractal dimension values from trabecular bone around implants as calculated from panoramic radiographs at 12 months revealed comparable results with implant-free healthy alveolar bone.