Avaliação histomorfométrica da osseointegração em superfície de implante bioativa de titânio revestida com fosfato de cálcio

Abstract

The study performed the evaluation and histomorphometric comparison of osseointegration on surfaces of implants composed of grade 4 titanium (Ti6Al4V) submitted to the treatment of sandblasting, acid erosion and calcium phosphate coating (BGTI37) in comparison to a microtexturized control surface without the (Ticp) from an in vivo study performed on male Wistar rats. The sample consisted of 24 tibiae with screws, measuring 1.5mm X 3mm randomly installed in the tibiae of twelve animals, where each animal received an implant with the treatment and another implant without coating to allow the comparison. The histomorphometric evaluation of osseointegration was performed by means of bone-implant contact (BIC) and bone surface fraction (BAFO) analysis, at 14 and 28 days, by a light microscope and analysis software of image. From the analysis, percentages were calculated for BIC and BAFO presenting mean values and standard deviation at the proposed times. The results were submitted to statistical test, Shapiro-Wilk to confirm normality and homoscedasticity. Student's t-tests of independent and dependent samples were used to evaluate and compare the different surfaces at different times. The study demonstrated a significant increase in BIC from 0.42 ± 0.08 at 14 days to 0.57 ± 0.13 at 28 days on the BGTi37 surface between the proposed times. The medullary portion was shown to be the region where the difference was significant (0.28 ± 0.21 - 14 days to 0.67 ± 0.14 - 28 days). There were no significant differences in BAFO values. Osseointegration was observed on both surfaces and in all conditions tested with an increase in bone formation between the 14 and 28 days period of the experimental surface in the spinal region by means of BIC.