The effects of ultraviolet photofunctionalization of implant on bone graft in critical one-wall defects around implant : a pilot study in beagle dogs

Abstract

Purpose: The conversion of implant surface from bioinert to bioactive by UV photofunctionalization can result better osseointegration and osteogenesis capabilities of titanium surface. The purpose of this study was to compare and evaluate, through histomorphometric and radiological assessment, the effects of UV photofunctionalization on an implant placed over a critical defect area with and without a bone graft.Materials &Methods: Four female beagle dogs (body weight 10 kg, age 12 months) were first divided into bone graft and control groups. Each group was again subdivided into UV-treated and control groups. The mandibular premolars in each dog were extracted. 12 weeks after extraction, implants were placed according to the condition of each group. Four and 12 weeks after implantation on left and right mandible, the dogs were sacrificed. The specimens were prepared for histomorphometrical and micro-computed tomographic analyses. Results: In both the 4-week and 12-week groups, UV-treated implant surfaces showed better osseointegration than on SA implant surfaces, while both implant surfaces were in direct contact with bone. The UV photofunctionalization barely showed any effect on implant surfaces placed over the critical defect without bone graft. After 12 weeks, however, UV photofunctionalization increased the amount of new bone formation. In implant surfaces placed over the critical defect with bone graft, UV photofunctionalization increased BIC and new bone formation at the initial stage (4 wks).Conclusion: Based on the results of this study, UV photofunctionalization on the surface of implants placed over large critical defects with bone graft aid initial osseointegration and osteogenesis. If the limitations of this study are addressed in subsequent experiments, it will be possible to examine UV photofunctionalization’s long-term positive effect on implants placed over large critical defects with bone grafts.