Abstract The aim of this study is to evaluate the biocompatibility and osteoconductivity in surgical defects of sheep tibias filled with 1% strontium-containing nanostructured hydroxyapatite microspheres (SrHA), stoichiometric hydroxyapatite without strontium microspheres (HA), or blood clots. Santa Ines sheep were subjected to three perforations on the medial side of the left tibia. The biomaterials were characterized by X-ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) before implantation and by X-Ray Microfluorescence (µFRX) and Scanning Electron Microscopy (SEM) after sheep tibias implantation. Surgical defects were filled with blood clots (control), SrHA (Group 1) or HA (Group 2). After 30 days, 5-µm bone blocks were obtained for histological evaluation, and the blocks obtained from 1 animal were embedded in methylmethacrylate for undecalcified sections. Mononuclear inflammatory infiltrate remained mild in all experimental groups. Giant cells were observed surrounding biomaterials particles of both groups and areas of bone formation were detected in close contact with biomaterials. All groups showed newly formed bone from the periphery to the center of the defects, which the control, HA and SrHA presented 36.4% (± 21.8), 31.2% (± 14.7) and 26.2% (± 12.9) of newly formed bone density, respectively, not presenting statistical differences. In addition, the connective tissue density did not show any significant between groups. The SrHA showing a higher volume density of biomaterial (51.2 ± 14.1) present in the defect compared to HA (32.6 ± 8.5) after 30 days (p = 0.03). Microspheres containing 1% SrHA or HA can be considered biocompatible, have osteoconductive properties and may be useful biomaterials for clinical applications.

Este trabalho apresenta os resultados de um estudo sobre a porosidade de testemunhos da Formação Resende na região da Bacia de Resende (Rio de Janeiro). A primeira etapa envolveu a seleção, desbaste do material (testemunhos) e preparação da amostra para caracterização no porosímetro e obtenção da porosidade efetiva. O material estudado é um arenito, friável, de granulometria grossa a muito fina retirado de três poços (GPR1, GPR2 e GPR3). Com a lógica fuzzy, aplicada aos dados de porosidade efetiva do perfil de raios gama - RG, foi construído um perfil sintético que identificou e corrigiu erros no cálculo da porosidade. Em seguida os resultados de porosidade dos testemunhos do poço GPR1 foram correlacionados aos dados de porosidade efetiva corrigidos a partir do perfil de RG, visando comparar os dois métodos. A análise do perfil sintético de porosidade calculado pela lógica fuzzy mostrou que este é um método promissor para filtrar e avaliar a qualidade de dados melhorando a interpretação de dados de perfilagem.

This work presents here a study on the porosity of cores from Resende Basin (Rio de Janeiro). The first step involved the selection, thinning of the material (core) and sample preparation for the use of porosimeter to obtain effective porosity. The material studied is sandstone, friable, coarse to very fine of three wells (GPR1, GPR2 and GPR3). The fuzzy logic (MatLab) was applied to the effective porosity data calculated from the gamma ray (GR) profile for the construction of a synthetic profile and from this we could identify the errors made in calculating the data. Then the results of porosity from the core were correlated with data from the corrected effective porosity (gamma ray profile) in order to prove the results obtained with both methods. The analysis of the synthetic porosity calculated by the fuzzy logic has shown that this is a promising method for assessing the quality of data and to obtain good fits.