RESUMO
Objective: To evaluate the possibility and efficiency of using adapted peri-implant bone evaluation method based on the principle of graphical superimposition and compare it to the possibilities of using sagittal sections of CBCT results to register the dynamics of peri-implant bone changes during the first year of implant functioning. Material and Methods: 108 pairs of DICOM data sets were selected and pre-anonymized and coded in Planmeca Romexis® Viewer software. Each pair of datasets consisted of a CBCT file, obtained immediately after the installation of a dental implant, and one year after its operation. The first method of peri-implant bone changes evaluation was carried out by analyzing the sagittal sections of the CBCT data from the mesial and distal sides of the implant. The second method was followed by original algorithm, which included specific steps of superimposition of graphical images. Results: Superimposition method helped to establish volumetric parameter of circular bone reduction around dental implants after 1 year of their functioning. Such average values for the maxillary distal implants were 3.547 mm3, maxillary frontal implants 3.118 mm3, mandibular distal implants 2.614 mm3, mandibular frontal implants 2.456 mm 3. Correlation values between averages of vertical bone loss parameters and volumetric bone loss parameters riches r=0.954. Among all patients the highest peri-implant bone reduction rates were observed in the distal and frontal areas of the maxilla, even though statistical difference among such parameters of implants installed at the areas of mandible and maxilla was not significant (p > 0.05). Such observation was established during the analysis of results obtained both by digital sagittal cross section from CBCT results and by superimposition method. Conclusion: Using the superimposition principle allows us to evaluate the individual indicator of volumetric bone loss at the peri-implant region. The possibility of taking into account the parameters of bone tissue volume reduction, instead of just geometrical parameter of bone height, allows to individualize the parameters of bone loss among patients of different prosthetic rehabilitation group.