ABSTRACT Purpose To analyze and compare the reactions at the interface between the composite, composed of fragmented heterologous mineralized bone matrix (MOMHF) and polymethylmethacrylate (PMMA), and the rabbit’s tibias, through macroscopic evaluation and scanning electron microscopy (SEM) in different periods. Methods In this study, 12 New Zealand adult rabbits were used (E1: n = 3, E2: n = 3, E3: n = 3 and E4: n = 3). They had the right tibial defects filled with composite and were evaluated immediately after surgery and at 30, 60, 90, and 120 days. Results The composites were incorporated and integrated into the recipient beds in 100% of the cases, defined by the MOMHF osseointegration and the PMMA fibrointegration, with no sign of infection, migration, or rejection. Conclusions The behavior of the composites in the recipient beds demonstrates that these biomaterials have the potential to be used in bone defect repairs, offering, thus, better quality of life to the orthopedic patient.

As fraturas representam o principal problema ortopédico na clínica de pequenos animais. O estudo de 333 casos em cães, e 37 em gatos diagnosticados nas principais unidades de atendimento veterinário da cidade de Maputo no período de 1998 a 2008 foi levado a cabo para analisar a frequência das fraturas. A maior incidência de fraturas foi registrada em animais com idade igual ou inferior a 2 anos (55,68%). Em ambas as espécies, os machos (58,38%) estiveram mais envolvidos em fraturas que as fêmeas. O esqueleto apendicular foi o mais acometido com 91,59% (cães) e 75,66% (gatos) do total de fraturas, sendo o fêmur [35,74% (cães) e 35,14% (gatos)] singularmente o mais envolvido em todas as espécies seguido pela tíbia e fíbula. Os atropelamentos por veículos motorizados foram responsáveis pela maior parte das fraturas, contudo, a frequência por agressão humana é bastante preocupante. Não há evidência da distribuição sazonal dos casos registrados.

The fractures represent an important health hazard in orthopedic practices of small animals. A Survey of 333 canine and 37 feline fractures diagnosed at main veterinary hospitals in Maputo between January 1998 and December 2008 was carried out aiming to analyze the frequency of fractures. The highest incidence was recorded in young animals (55.68%) under two years of age. The males were more involved (58.38%) than the females. The appendicular skeleton showed more frequency of fractures 91.59% (dogs) and 75.66% (cats), and among various bones, the femur [35.74% (dogs) and 35.14% (cats)] was more affected followed by tibia and fibula in both species. Most fractures were caused by vehicle accidents; however, the frequency by human aggression is quite worrying. There was no evidence of seasonal distribution of the recorded fractures

PURPOSE: To evaluate the performance of composites consisting of fragmented cortical bone heteroimplant in association with methylmethacrylate preserved in 98% glycerin, in segmental bone defect of rabbit tibia medial metaphysis. METHODS: In this study were used twelve adult New Zealand rabbits, divided into three groups of four animals each: G30 (30 days), G60 (60 days) and G90 (90 days). The bone defects previously created in the tibia were filled with composites and both were evaluated by cone-beam computed tomography, immediately after surgery and after 30, 60, and 90 days. RESULTS: The composites fulfilled and remained in the sites of bone defects in all cases and were not registered signals of infection, migration or rejection. CONCLUSIONS: The implanted composites promoted the bone defects repair without signals of infection and/or rejection. The composites are one more option for bone defects repair.