Augmentation of the maxillary sinus: comparison of bioimplants containing bone morphogenetic protein and autogenous bone in a rabbit model.
OBJECTIVE
To evaluate the effectiveness of various bioimplants used for augmentation of the maxillary sinus floor by means of a rabbit model.


METHODS
Bone was harvested from the posterior iliac crest of 40 adult New Zealand white rabbits to allow bilateral augmentation of the floor of the maxillary sinus with autogenous bone or other materials. One of the following was grafted to the maxillary sinus of each rabbit: particulated autogenous bone, demineralized bone matrix (DBM), DBM combined with purified bone morphogenetic protein (BMP-DBM bioimplants) and bioimplants consisting of a poloxamer gel with BMP in 1 of 2 different doses. Animals were sacrificed at 2 or 8 weeks. Histologic examination was used to assess biologic healing in the various samples. Histomorphometry was used to demonstrate and quantify bone formation.


RESULTS
After 2 weeks, the BMP-containing bioimplants had produced more new bone than any of the other materials. Particulated autogenous bone grafts produced less new bone initially (after 2 weeks), but the amount of bone produced by these grafts gradually increased, to levels comparable to the BMP-containing bioimplants by 8 weeks. For groups in which the poloxamer gel was used as a carrier for BMP or where BMP was used in combination with DBM, the amount of bone generated by 8 weeks was similar to that produced by autogenous bone.


CONCLUSIONS
The rabbit maxillary sinus model allowed evaluation of multiple types of bioimplants that could be suitable for peri-implant maxillary reconstruction. BMP-containing bioimplants demonstrated promise as alternatives to autogenous bone grafts for sinus-augmentation procedures. These bioimplants had more rapid initial bone production than all other materials, including autogenous bone. In the future, such biomaterials may enable earlier placement of dental implants into augmented maxillary sinuses.
Faculty of dentistry, University of Toronto, 124 Edward Street, Toronto, ON M5G 1R6. c.clokie@dentistry.utoronto.ca
Steven K C
SK
Ho
Sean A F
SA
Peel
Zhen Ming
ZM
Hu
George K B
GK
Sándor
Cameron M L
CM
Clokie
D000818:Animals; D001857:Bone Matrix / Q000637:transplantation; D055419:Bone Morphogenetic Protein 7 / Q000008:administration & dosage*; D001861:Bone Regeneration / Q000187:drug effects*; D016025:Bone Transplantation / Q000379:methods*; D004337:Drug Carriers; D008297:Male; D008443:Maxillary Sinus / Q000601:surgery*; D023421:Models, Animal; D013516:Oral Surgical Procedures, Preprosthetic / Q000379:methods*; D020442:Poloxamer; D011817:Rabbits
D055419:Bone Morphogenetic Protein 7; D004337:Drug Carriers; D020442:Poloxamer