ABSTRACT
Objective: to perform a histological analysis of nylon, carbon, and polypropylene fiber-enriched calcium phosphate cement (CPC) for use as bone substitute in the femur or rats. Materials and method: Fiber-enriched CPC blocks (6-mm diameter, 2-mm thickness) were im-planted in the femur of 20 male Wistar rats. The ani-mals were euthanized at 30, 60, 90, and 120 days, with removal and histological assessment of specimens. Results: Biocompatibility, resorption, and osteoconduc-tion were assessed. At all times, histological assessment revealed the formation of dense connective tissue with low cellularity, little vascularization, and a few mono-nuclear cells. Surrounding the implant, slight resorption and hyalinization of peripheral collagen fibers were ob-served, with evidence of incorporation of implant mate-rial into connective tissue. Osteoid tissue was observed at 120 days. Bone resorption surrounding the implant was not significant. Conclusion: Based on the present criteria, CPC seems adequate for use as bone substitute.
ABSTRACT
Introduction: osteoradionecrosis (ORN) of facial bones is a serious complication of radiotherapy. Objective: this literature review was performed to study maxillary osteoradionecrosis, its incidence, classification, risk factors, physiopathology, prevention, and current treatment. Literature review: literature search using Medline was performed for all relevant articles with specific keywords from January 2000 to November 2011 aiming to find current data available on ORN and the paradigm change in physiopathology and prevention of the disease. The literature reviewed showed lack of either controlled or randomized trials, a few prospective studies, and a great amount of retrospective studies. Final considerations: adjunctive hyperbaric oxygen (HBO) therapy may be applied for osteoradionecrosis prevention, before and after dental procedures, with satisfying results. Nonetheless, several studies indicated that HBO therapy is not beneficial.