Complications Associated With the Use of Recombinant Human Bone Morphogenic Protein–2 in Ridge Augmentation: A Case Report
This case report aims to describe in detail a complication associated with resorption of regenerated bone following implant placement and ridge augmentation using recombinant human bone morphogenic protein–2 (rhBMP-2) in combination with allograft and xenograft. Bilateral maxillary sinus and ridge augmentation procedures were completed using rhBMP-2 combined with allograft and xenograft. Five months later, significant bone augmentation was achieved, which allowed for the placement of 4 implants. Upon stage 2 surgery, significant dehiscence was noted in all implants. Treatment steps to address this complication included implant removal, guided bone regeneration with xenograft only, and placement of new implants followed by soft-tissue grafting. At the time of publication, this patient is status 1½ years post case completion with maintenance of therapy outcomes. Off-label use of rhBMP-2 has gained significant acceptance in implant dentistry. However, there is limited evidence regarding the bone maturation process when rhBMP-2 is combined with other biomaterials. More research may be needed regarding the timing and process of bone healing in the presence of rhBMP-2, in an effort to avoid surgical complications.
Figure 1. (a,b) Patient presented with a heavily restored dentition and multiple teeth with recurrent caries. Figure 2. (a,b) Significant ridge collapse that did not allow for prosthetically driven implant positions. Figure 3. (a,b) Bilateral external sinus lifts for maxillary sinus augmentation.
Figure 4. (a,b) Bilateral ridge augmentation using titanium mesh (T-mesh). Figure 5. Absorbable collagen sponge soaked in recombinant human bone morphogenic protein–2 and mixed with allograft and xenograft. Figure 6. (a,b) Uncomplicated healing at 5 months with no T-mesh exposure. Figure 7. (a,b) Implant placement at No. 4, 5, 12, and 13 sites with 2 mm of buccal bone thickness.
Figure 8. (a,b) Alloderm RTM placed over the implants to thicken the tissue. Figure 9. (a,b) Dehiscence approximating No. 4, 5, 12, and 13 implant apices at stage 2 surgery. Figure 10. (a,b) Implant removal, extraction of No. 14, and placement of tenting screws for space maintenance at guided bone regeneration.
Figure 11. (a,b) Bone augmentation covering the head of the tenting screws 7 months after guided bone regeneration. Figure 12. (a–c) Placement of 5 implants using Straumann guided surgery. Periapical X rays showing implant position as planned on cone-beam computertized tomography.
Figure 13. (a,b) Shallow buccal vestibule depth and lack of keratinized gingiva (KG) around implants. Figure 14. (a,b) Bilateral free gingival grafts to increase the amount of KG and deepen the vestibule. Figure 15. (a,b) Final restorations. The significant increase in keratinized gingiva around implants is noticeable. Panoramic X ray taken at 1 year after completion of treatment, showing preservation of peri-implant bone levels.
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