Abstract - Guided Bone Regeneration Utilizing a Calcium Phosphosilicate Alloplastic Putty Bone Substitute

Abstract - Guided Bone Regeneration Utilizing a Calcium Phosphosilicate Alloplastic Putty Bone Substitute

G. Kotsakis*, L. Mahesh **, H. Prasad+, M. Rohrer++, J. Hinrichs+++:
Background: Use of guided bone regeneration (GBR) for the treatment of horizontal ridge deficiencies is considered a safe and predictable modality. However, this therapeutic  approach is technique sensitive and time consuming. The purpose of this study is to evaluate calcium phosphosilicate alloplastic bone putty (CPS) for its handling characteristics  and use in GBR. 
 
Materials & Methods
In this case series study, ten sites exhibiting a Seibert Class I defect were treated with GBR. Full-thickness mucoperiosteal flaps were reflected, and bone calipers were used to  measure the buccal/palatal dimension of each defect prior to ridge augmentation with CPS and again prior to implant placement. Cortical plates of the ridge deficiencies were  perforated prior to grafting with CPS. A resorbable membrane was positioned over the CPS, and the flaps were sutured with primary closure. An appropriate post-operative  antibiotic and analgesic was prescribed in accordance with the participant’s medical history. Core biopsies were obtained in conjunction with placement of a dental implant in five  of the sites at approximately six months following the CPS graft. Bone core samples were fixed in 10% buffered formalin and submitted for histological and histomorphometric  analysis at the Hard Tissue Research Laboratory, University of Minnesota. Participants were followed for at least 12 months following delivery of the implant-supported  restorations.
 
Results: The average duration of surgery from first incision to final suture was 37.75 + 7.14 minutes. The mean time between ridge augmentation and implant placement was 6.1  + 0.3 months. The average gain in buccal/palatal ridge width was 3.67 + 0.51 mm. All ten grafted ridge deficiencies were able to accommodate a 4-mm diameter implant, which  subsequently became osseo-integrated for a cumulative success rate of 100%. The mean distance between the margin of the implant platform and the coronal edge of bone- toimplant contact was 0.68 + 0.27 mm at the 12-month evaluation. Histological and histomorphometric evaluation showed the percentage of the vital bone to be found at exactly  100% in all patients. The CPS particles were surrounded by newly formed bone and bridging between CPS particles and vital bone was seen in many microphotographs. The  presence of osteoblasts and seem of osteoid were observed in all the cases. Handling characteristics of the CPS putty were adequate for viscosity and consistency to support a  resorbable GBR membrane, thereby minimizing the time required to perform the GBR procedure.
 
Conclusion
Calcium phosphosilicate alloplastic bone putty provides adequate membrane support and scaffolding for guided bone regeneration of Siebert Class I ridge deficiencies. The handling  characteristics of CPS putty minimize surgery time and simplify GBR protocol. Further randomized, controlled clinical trials are needed to validate these results. 
 
 
* Resident, Advanced Education Program in Periodontology, University of Minnesota, Minneapolis, Minnesota.
**Private Practice, New Delhi, India.
+ Senior Research Scientist, Associate Director, Hard Tissue Research Laboratory, University of Minnesota, Minneapolis, Minnesota.
++ Professor and Director, Hard Tissue Research Laboratory, University of Minnesota, Minneapolis, Minnesota.
+++Professor and Director, Advanced Education Program in Periodontology, University of Minnesota, Minneapolis, Minnesota.