Study on the efficacy of biodegradable poly(L-lactide) mesh for supporting transplanted particulate cancellous bone and marrow: experiment involving subcutaneous implantation in dogs.
Poly(L-lactide) (PLLA) mesh sheets, monofilaments and mesh cylinders filled with fresh autogenic particulate cancellous bone and marrow (PCBM) were implanted subcutaneously into the back of 22 adult dogs for 1 yr. Polypropylene (PP) was used as a control. The inflammatory response to PLLA mesh sheets was slight, similar to PP mesh sheets. However, 3 months after implantation, histiocytes and multinucleate giant cells appeared on the surface of the monofilaments of PLLA mesh sheets and gradually increased in number as the monofilaments were degraded and absorbed. Almost no inflammatory cellular infiltration was seen in the tissue around PLLA mesh sheets or between the monofilaments. When a PLLA mesh cylinder filled with PCBM was implanted subcutaneously, the bone formation reached its peak 1 month after implantation, as in the case of a similar PP mesh cylinder, and bone formation was observed along the inner wall of the cylinder. In addition, a vascular net was abundant within the cylinder. The mechanical strength of the test material (PLLA monofilaments) did not change for almost 2 months after implantation, and 80% of its initial strength was retained for 3 months. These observations suggest that a PCBM graft supported by PLLA mesh would be very effective in the reconstruction of damaged maxillofacial bones, since histological tissue reactions associated with biodegradation of the PLLA mesh are mild and the PLLA mesh does not interfere with bone formation of PCBM. It was also found that the PLLA mesh retains its mechanical strength long enough to allow the PCBM transplant to develop sufficient strength to sustain the damaged region.
Kinoshita
Y
Y
Second Department of Oral and Maxillofacial Surgery, Kanagawa Dental College, Yokosuka, Japan.
Kirigakubo
M
M
Kobayashi
M
M
Tabata
T
T
Shimura
K
K
Ikada
Y
Y
D000818:Animals; D001673:Biodegradation, Environmental; D016026:Bone Marrow Transplantation; D016025:Bone Transplantation; D004285:Dogs; D005549:Foreign-Body Reaction / Q000209:etiology / Q000473:pathology; D016348:Osseointegration; D011091:Polyesters; D011126:Polypropylenes; D019736:Prostheses and Implants
D011091:Polyesters; D011126:Polypropylenes; C033616:poly(lactide)