Injectable Calcium Phosphate Cement as a Bone-Graft Material Around Peri-implant Dehiscence Defects: A Dog Study

Purpose: Peri-implant dehiscence defects occur frequently after dental implant placement. Various graft materials and techniques are proposed for treatment. In this study, an injectable calcium phosphate cement (Augmentech, Wetzlar, Germany) applied to a peri-implant defect was investigated. Materials and Methods: Standardized buccal dehiscence defects (5.8 x 3.8 mm) were surgically created after implant site preparation in the right proximal tibiae of 5 beagle dogs. Fifteen stepped cylindrical implants (13 x 3.8 mm diameter) were inserted (3 per dog), and Augmentech injectable calcium phosphate cement was injected into the dehiscences. The bone at the distal side of the implant was left intact to serve as a control. Postsurgically, each dog received double staining of 2 fluorescent labels for estimation of bone cell activity at baseline and after 11 weeks of healing. The animals were sacrificed after 12 weeks. Dissected blocks were processed for histologic, histomorphometric, and fluorescence microscopic analysis, ie, percentage of bone-to-implant contact (BIC) and percentage linear bone height (LBH) were measured. Student t and Mann Whitney U tests were used for statistical analysis (P .05). Results: Healing was uneventful in all dogs. Augmentech injectable calcium phosphate cement showed good space maintenance and osteoconductive properties with no foreign body reaction. BIC was 34.42 (± 19.88) and 37.00 (± 21.33) (P = .375), while LBH was 84.23 (± 19.73) and 96.10 (± 6.66) (P = .125) for test and control sites, respectively. Conclusion: Within the limits of the present study, it was concluded that Augmentech injectable calcium phosphate cement may be a suitable material for the treatment of buccal dehiscence defects around dental implants. Keywords: calcium phosphate, dehiscence, dental implant, dog study, grafting