Experimental transplantation of hydroxylapatite-bone composite grafts.
OBJECTIVE
This study was undertaken to determine if autogenous bone can be cultivated in vivo in a porous hydroxylapatite (HA) matrix by ingrowth from underlying bone and if this autogenous HA-bone composite graft can then be transplanted.


METHODS
Five Göttingen minipigs received subperiosteal implantation of one HA block each (40 x 10 x 10 mm), covered by a polylactic membrane, on the ascending ramus of the mandible. After 5 months, half of each implant was harvested and transplanted as an onlay graft to the horizontal ramus of the mandible with simultaneous insertion of a titanium implant. Polychrome fluorescence labeling was done 1, 2, 4, and 8 weeks postoperatively. After 3 months, the vascular system of the animals was filled with BaSO4 for microangiographic examination, and all blocks were retrieved.


RESULTS
Fluorescence microscopy showed that there was a significant decrease in deposition of the label in the grafted blocks at 1 week when compared with later labels. After the second week, there were no significant changes. A 20% to 30% decrease in the frequency of fluorochrome staining was noted in the upper third of each block. In this region, microangiography demonstrated highly vascularized tissue and limited bone resorption.


CONCLUSIONS
It was concluded that cultivation of mandibular bone in a porous matrix under guided bone regeneration is possible and that this autogenous HA-bone composite graft can be transplanted at a later date.
Schliephake
H
H
Department of Oral and Maxillofacial Surgery, Medzinische Hochschule Hannover, Germany.
Neukam
F W
FW
Hutmacher
D
D
Wüstenfeld
H
H
D000792:Angiography; D000818:Animals; D000880:Anthraquinones; D001861:Bone Regeneration; D001862:Bone Resorption / Q000000981:diagnostic imaging / Q000473:pathology; D016025:Bone Transplantation / Q000379:methods* / Q000473:pathology; D015921:Dental Implants; D017886:Durapatite; D005260:Female; D005452:Fluoresceins; D005456:Fluorescent Dyes; D006253:Haversian System / Q000473:pathology; D007773:Lactates; D019344:Lactic Acid; D008334:Mandible / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D008852:Microradiography; D008856:Microscopy, Fluorescence; D010006:Osteoblasts / Q000473:pathology; D011091:Polyesters; D011108:Polymers; D019736:Prostheses and Implants; D013552:Swine; D013556:Swine, Miniature; D013752:Tetracycline; D014025:Titanium; D014182:Transplantation, Autologous
D000880:Anthraquinones; D015921:Dental Implants; D005452:Fluoresceins; D005456:Fluorescent Dyes; D007773:Lactates; D011091:Polyesters; D011108:Polymers; C083098:calcein green; D019344:Lactic Acid; C033616:poly(lactide); C010078:alizarin; D017886:Durapatite; D014025:Titanium; D013752:Tetracycline; C007740:fluorexon