Initial endosseous healing response to lactide/ glycolide copolymer

Resumo

Introduction: The search for less invasive treatments, with fast and
effective bone regeneration, has lead to the development of synthetic
bioresorbable alternatives for bone graft. The commercial product
FisiograftTM gel (Ghimas Spa, Italy), based on lactide-glycolide
copolymer, is used as an injectable biocompatible and bioresorbable
material for filling bone defects in dental surgery applications. These
polymers are also used in the production of suture threads, pins and
plates for bone fixation, and barriers for guided tissue regeneration.
Objective: The main objective of this pilot study was to observe the
initial bone healing response after the application of polylactide-glycolide
graft material in adult animals. Material and methods: Bone defects
were prepared in right and left femora of 12 month-old male Wistar
rats. The defects in one leg received the synthetic graft material and the
contra-lateral defects did not receive any treatment. After four days, the animals were subjected to euthanasia, the femora were removed, and
tissue blocks were prepared for histological analysis. Results: Blood
clot remained in the centre of control defects with initial connective
tissue organization on the edges. The graft material was observed in the
centre of the treated defects, restricted to the area where it was applied,
with neovascularization next to the graft material. The pattern of bone
healing did not differ between groups, starting from the margins of the
defects and from bone fragments, with neovascularization followed
by deposition of non-mineralized bone matrix towards the centre.
Conclusion: The results indicate that the lactide-glycolide copolymer
gel was effective as a filling and osteoconductive material, allowing
tissue healing during its resorption process. Additional studies are
necessary to verify its capacity to promote bone regeneration.