Effect of Using Cantilever Bar on the Supporting Structures in Implant Supported Mandibular Overdentures

Statement of problem free overdenture rotation during function lead to bone resorption in the posterior edentulous regions. Purpose The aim of this study was to compare the influence of incorporating a cantilever extension in two implant supported bar mandibular overdentures on the peri-implant tissues in two groups of completely edentulous patients receiving two implants in the mandibular canine region. Materials and method Ten completely edentulous patients were randomly assigned into two equal groups, in the first group the removable complete overdenture is supported and retained to the implants with metallic bar attachment with bilateral posterior extension, in the second group the removable complete overdenture is supported and retained to the implants with metallic bar attachment with no posterior extension. Marginal bone height and bone density changes around the implants were measured radiographically using cone beam CT. The data were collected, arrayed and statistically compared. Results regarding bone density radiographically there was no significant difference between the two groups while group one recorded significant higher marginal bone loss radiographically than group two. Conclusion although that there was a significant difference between the two groups regarding marginal bone loss, it was within the normal rate reported in the literature.