RESUMO As estratégias atuais no design de biomateriais incluem a alteração das propriedades da superfície do biomaterial para direcionar sistematicamente o comportamento celular. O titânio é o material mais prevalente para uso em implantes devido às suas propriedades mecânicas. Modificações na superfície de titânio podem otimizar a osseointegração de um implante modulando a resposta imunossupressora, acelerando o processo de cicatrização e reduzindo o tempo de tratamento. O crescimento de nanotubos de TiO2 através da anodização pode alterar as propriedades da superfície do titânio comercialmente puro, permitindo uma melhor resposta quando inserido no corpo humano. Objetivo do presente trabalho foi o crescimento de nanotubos de TiO2 na superfície de discos de titânio comercialmente puro e a redução do tempo de anodização, com agitação durante a oxidação anódica, tensão de 30V e eletrólito composto por 90-10% (v/v) de etilenoglicol-H2O e 1% NH4F (m/m). Para determinar a melhor intensidade de agitação foi estabelecido um tempo de 20 minutos. A classificação da intensidade da agitação foi feita pelo método de observação, classificada como fraca, moderada e vigorosa. Para determinar o melhor tempo de oxidação anódica, foi estabelecida intensidade de agitação moderada. O tempo de anodização deve permitir que a estrutura se reorganize e aumente o grau de auto-organização, assim, foram estabelecidos tempos de 20, 30 e 40 minutos. Em seguida, as amostras foram submetidas à calcinação em forno mufla EDG com taxa de aquecimento de 5ºC/minuto, mantida por 1 hora a 450ºC. A morfologia da superfície foi analisada por microscopia eletrônica de varredura (MEV), ângulo de contato e difração de raios X (DRX).

ABSTRACT Current strategies in the design of biomaterials include altering the surface properties of the biomaterial to systematically direct cellular behavior. Titanium is the most prevalent material for use in implants due to its mechanical properties. Modifications to the titanium surface can optimize the osseointegration of an implant by modulating the immunosuppressive response, accelerating the healing process and reducing treatment time. The growth of TiO2 nanotubes through anodization can alter the surface properties of commercially pure titanium, allowing a better response when inserted into the human body. Objective of the present work was the growth of TiO2 nanotubes on the surface of commercially pure titanium discs and the reduction of anodization time, with agitation during anodic oxidation, voltage of 30V and electrolyte composed of 90-10% (v/v) ethyleneglycol-H2O and 1% NH4F (w/w). To determine the best agitation intensity, a time of 20 minutes was established. The agitation intensity was classified by the observation method, classified as weak, moderate and vigorous. To determine the best anodic oxidation time, moderate agitation intensity was established. The anodizing time should allow the structure to reorganize and increase the degree of self-organization, thus, times of 20, 30 and 40 minutes have been established. Then, the samples were subjected to calcination in an EDG muffle furnace with a heating rate of 5ºC/minute, maintained for 1 hour at 450ºC. The surface morphology was analyzed by scanning electron microscopy (SEM), contact angle and X-ray diffraction (XRD).

Titanium (Ti) and its alloys are widely used for medical and dental fields due to their excellent biocompatibility, high corrosion resistance, high specific strength and excellent mechanical properties. Different methods have been developed to improve the surface properties of titanium-based implant materials, and consequently the bone-bonding ability. The Ti-7.5Mo alloy was activated by an alkaline treatment with 5M NaOH, heat treatment and subsequent immersion in SBFx5 to investigate the in vitro response of osteoblastic-like cells MG-G3 on altered biomimetic surfaces. Sample surfaces were characterized by scanning electron microscopy. Cytotoxicity was assessed by the MTT assay, total protein content, alkaline phosphatase activity (ALP) and mineralized bone-like nodule formation. It was shown the que alkali treatment led to the formation of sodium titanate and immersion in SBFx5 formed a film of calcium phosphate. The alkaline treatment and heat treatment of 7.5 Ti-Mo alloys followed by soaking them in SBFx5 for 24 hours is a suitable technique once the final samples were biocompatible, allowed the attachment of the osteoblastic-like cells (MG-G3), and increased the mineralized like-bone nodules formation by these cells.

Titanium and its alloys have been used in dentistry to due their excellent corrosion resistance and biocompatibility. However, titanium coating is bioinert material and it cannot chemically bond to bone tissue. The purpose of this work was evaluating the bioactivity of Ti-7,5Mo alloy after chemical treatment using H2SO4 / H2O2 and soaking in SBF. Samples were chemically treated at room temperature for 4 h with a solution consisting of equal volumes of concentrated H2SO4 (200 ml) and 30% aqueous solution H2O2 (200 ml). The oxidized samples were rinsed with distilled water and were heat treated at 600°C for 1h in a electrical furnace in air. Then, all samples were immersed in SBF (Simulated Body Fluid) for 7 and 14 days to form a calcium phosphate (Ca/P) coating on the surface. Surfaces were characterized by using SEM, AFM and contact angle. The results indicated that calcium phosphate (Ca/P) was formed on surface of Ti-7.5Mo experimental alloy.