Comparing the effect of canine guided versus group function occlusion on the vertical bone loss around implants retaining mandibular hybrid prostheses

Aim: The aim of this study was to evaluate the amount of marginal bone loss around mandibular fixed hybrid prostheses with different occlusal schemes among mandibular completely edentulous patients opposed by dentate maxilla. Materials and methods: This study was conducted on 18 patients. The patients were distributed in two groups. All patients were with mandibular completely edentulous arch and were rehabilitated with five intra-foraminal implants which were restored by implant supported fixed hybrid prosthesis. For the first group: (C) canine guided occlusal scheme was used. As for the second group: (G) group function occlusal scheme was used. The amount of marginal bone loss in each group was measured by CBCT at 0, 6 and 12 months after delivery. Results: Within both intervals, for left implant (1) and right implant (2), distal bone loss values measured in group function group were significantly higher than those in canine guided group (p<0.05). While for other implants the difference was not statistically significant (p>0.05) at the end of the study. There was no significant difference between total bone loss values measured in both groups (p>0.05) at the end of the study. Conclusion: Both canine guided and group function occlusion are accepted occlusal schemes for fixed implant prosthetics, but canine guided occlusion tends to distribute the forces more evenly leading to more even bone loss than group function which concentrates stresses on the distal implants threatening the longevity of the distal implant.