Comparison of Bovine Fascia and Evolution Membrane in Regeneration on Parietal Bone of Rabbit

Use of bone substitutes and membranes is an increasingly popular technique to stimulate new bone formation for treatment of orthopedic disorders resulting from bone defects and deficits and has been accepted as a standard treatment modality. Considering the use of bovine fascia as an absorbable membrane, this study compared the rate of bone formation after using bovine fascia and a collagen membrane (Evolution) in a rabbit model. In this experimental study 4 male New Zealand rabbits with a mean weight of 2.5 kg were used. After anesthetizing, three bone defects with 8 mm diameter were created bicortically in the parietal bone of the animals. Two defects were covered randomly with bovine fascia or ''Evolution" membrane and one remained uncovered as the control. After 12 weeks the rabbits were sacrificed and the bone formation was determined histologically. The bone type, inflammation, necrosis and fibrosis were also compared in the three groups and the data was analyzed using Jonckheere-Terpstra test. Out of 4 bovine fascia specimens, half of them showed no bone formation, one showed 33%-36% bone formation and the remaining one showed more than 66% bone formation. Half of the defects covered by "Evolution" membrane showed no bone formation, and the remaining two showed bone formation of less than 33%. In the control group, half showed no bone formation, and the remainder of the samples showed bone formation of more than 66%. No statistically significant difference in terms of bone formation was found between the three groups. From the aspect of type of bone, bovine fascia samples showed the formation of woven and lamellar bone each in one sample, two specimens in "Evolution" membrane group showed lamellar bone and two specimens in the control group showed woven bone formation. The three groups had no significant differences with regard to bone type, inflammation, necrosis or fibrosis. The present study showed that bone regeneration occurred in the defects covered with bovine fascia, "Evolution" membrane and control group was similar without any significant difference. Thus, the bovine fascia can be used as an alternative for "Evolution" membrane to induce bone formation. However, neither bovine fascia nor the "Evolution" membrane could facilitate bone formation as well as the control group.