title: Use of resorbable screws for autogenous onlay block graft fixation: a histological analysis in rabbits.
abstract: The aim of the present in vivo study is to histologically evaluate and compare the use of resorbable screws based on poly(L-co-D,L lactide) 70:30 for fixation of autogenous bone grafts in rabbit tibiae. As control group, titanium (Ti-6Al-4V Grade V) screws were used. For this purpose, 15 white New Zealand male rabbits, aged 6 months and weighing between 3.8 and 4.5 kg, were used. From each animal, 2 total-thickness bone grafts were removed from the cranial vault: one was stabilized with a resorbable screw while the other was stabilized with a metallic one. Animals were divided into 3 groups, according to the sacrifice period: 3, 8, and 16 weeks postoperatively. After histological processing, cuts were stained with hematoxylin and eosin and submitted for descriptive histological analysis under light microscopy. It was found that the fixation system based on the polymer showed a histological behavior similar to metallic screws. For both groups, the bone graft was incorporated, with the presence of bone formation between the graft and receptor site. In none of the groups were undesirable inflammatory responses or foreign body reactions observed. Based on histological findings and on this experimental model, it is possible to conclude that the internal fixation system based on the poly(L-co-D,L lactide) 70:30 polymer is effective for fixation of autogenous bone grafts, with results that are comparable to the titanium fixation system.
authors: 1  Department of Oral and Maxillofacial Surgery, Ponta Grossa State University, Ponta Grossa, Brazil.
authors: Leandro Eduardo
authors: LE
authors: Klüppel
authors: Glaykon Alex Vitti
authors: GA
authors: Stabile
authors: Fernando
authors: F
authors: Antonini
authors: Frederico Felipe
authors: FF
authors: Nascimento
authors: Marcio
authors: M
authors: de Moraes
authors: Renato
authors: R
authors: Mazzonetto
mesh_terms: D020341:Absorbable Implants; D000497:Alloys / Q000737:chemistry; D000818:Animals; D064592:Autografts / Q000473:pathology / Q000637:transplantation*; D001863:Bone Screws; D016025:Bone Transplantation / Q000295:instrumentation*; D003238:Connective Tissue / Q000473:pathology; D006253:Haversian System / Q000473:pathology; D008297:Male; D023421:Models, Animal; D020556:Neutrophil Infiltration / Q000502:physiology; D010011:Osteocytes / Q000473:pathology; D010012:Osteogenesis / Q000502:physiology; D011091:Polyesters / Q000737:chemistry; D011817:Rabbits; D011897:Random Allocation; D013977:Tibia / Q000601:surgery; D013997:Time Factors; D014025:Titanium / Q000737:chemistry
chemical_list: D000497:Alloys; D011091:Polyesters; C031462:titanium alloy (TiAl6V4); C033616:poly(lactide); D014025:Titanium
keywords: biocompatible materials; bone graft; resorbable screws