Development of a Novel Nanotextured Titanium Implant. An Experimental Study in Rats.

This animal study evaluated the osseointegration level of a new nanotextured titanium surface produced by anodization. Ti-cp micro-implants (1.5 mm diameter by 2.5 mm in length) divided into two groups: titanium nanotextured surface treatment (Test Group) and acid etched surface treatment (Control Group). Surface characterization included morphology analysis using scanning electron microscopy and wettability by measuring contact angle. Sixteen Wistar rats were submitted to two micro implants surgical placement procedures. In each rat, one type of micro implant placed in each tibia. The animals sacrificed after two (T1) and six weeks (T2) post-implantation. After the euthanasia, tibias processed for histomorphometric analysis, which allowed the evaluation of bone to implant contact (BIC) and the bone area fraction occupancy between the threads (BAFO). Our surface analysis data showed that the Control Group exhibited an irregular and non-homogenous topography while the Test Group showed a nanotextured surface. The Test Group showed higher wettability (contact angle = 5.1 ± 0.7°) than the Control Group (contact angle = 75.5 ± 4.6°). Concerning the histomorphometric analysis results for T1, Control and Test groups showed BIC percentages of 41.3 ± 15.2% and 63.1 ± 8.7% (p < 0.05), respectively, and for BAFO, 28.7 ± 13.7% and 54.8 ± 7.5%, respectively (p < 0.05). For T2, the histomorphometric analysis for Control and Test groups showed BIC percentages of 51.2 ± 11.4% and 64.8 ± 7.4% (p < 0.05), respectively and for BAFO, 36.4 ± 10.3% and 57.9 ± 9.3% (p < 0.05), respectively. The findings of the current study confirmed that the novel nanotextured surface exhibited superior wettability, improved peri-implant bone formation, and expedited osseointegration

Influência da agitação no crescimento de nanotubos de TiO2 na superfície de discos de titânio comercialmente puro

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 autoorganização, 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).Palavras-chave: Agitação. Anodização. Biomateriais. Titânio.

Ti-25Nb-25Ta alloy treated by plasma electrolytic oxidation in phosphoric acid for implant applications

Among titanium alloys with non-toxic elements, the Ti-25Nb-25Ta alloy has good elastic behavior for applications in osseous implants, biocompatibility, and excellent corrosion resistance. The present study aimed to better the biocompatibility characteristics of Ti-25Nb-25Ta alloy modifying its surface through Plasma Electrolytic Oxidation (PEO) treatment. The formed oxide coating is amorphous and composed of two distinct porous formations: smaller hole-shaped pores and larger volcano-like pores. The regions with the formation of smaller pores and in the hole shaped presented the highest atomic percentage of the chemical element phosphorus. Nanoindentation tests have shown that the hardness of the Ti-25Nb-25Ta alloy is slightly lower than the commercially pure grade 2 titanium (a material used as reference), while elastic modulus measurements of Ti-25Nb-25Ta presented more suitable values for implant application (lower values when compared with titanium reference). After PEO treatment there were significant mechanical surface improvements (increased fairly surface hardness and decreased elastic modulus) for application in osseous tissue. Despite the Ti-25Nb-25Ta alloy presented excellent characteristics for applications in hard biological tissues, the PEO treatment better its features.Keywords: Titanium alloy, Ti-25Nb-25Ta, nanoindentation, mechanical properties, Plasma Electrolytic Oxidation.

Incorporation Of Bisphosphonates In Surface Of The Ti30Ta After Biomimetic Treatment

The purpose of this study was the incorporation of the bisphosphonate (sodium alendronate) in surface of the Ti30Ta alloy after biomimetic treatment. In vitro and in vivo studies were made for to evaluate its incorporation and enhance of the osseointegration

Oxygen diffusion in Ti-10Mo alloys measured by mechanical spectroscopy

The addition of interstitial elements in metals, as titanium and its alloys, causes alterations in their mechanical properties, making them either softer or harder, for example. The internal friction measurements have been frequently used in order to verify the behavior of these interstitials atoms in metallic alloys. This paper presents the oxygen diffusion in Ti-10Mo alloy by the analysis of the mechanical relaxation spectra, in the temperature range of 350-600 K. The relaxation structure obtained was analyzed by means of the frequency dependence of the peak temperature and by using a simple mathematical treatment of the relaxation structure and the Arrhenius law.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Biocompatibility of experimental Ti-30Ta implants with compromised primary stability: effect of TEA

Purpose: Ti-Ta alloys have high potential for dental application due to a good balance between high strength and low modulus. Absence of primary anchoring may occur when dental implants are installed immediately after tooth extraction. Tranexamic acid (TEA) is used to reduce fibrin degradation and can prevent early blood clot breakdown. The aim of this study was to evaluate the biocompatibility of Ti-30Ta implants associated or not with tranexamic acid and installed with compromised primary stability. Methods and materials: Fabricated were 20 implants of titanium ASTM F67 (Grade 4) and 20 implants of Ti-30Ta alloy with dimensions of 2.1 mm × 2.8 mm Ø. They were divided (n = 10) into Group I (Ti machined), Group II (Ti machined/tranexamic acid), Group III (Ti-30Ta alloy) and Group IV (Ti-30Ta/tranexamic acid) and were implanted in tibia (defects with 2.5 mm × 3.2 mm Ø) of 40 male rats (250 g). The surgical sites were rinsed with 5% tranexamic acid solution in Groups II and IV. The animals were euthanized at 45 days postoperative. The pieces were processed in methyl methacrylate (Stevenel's blue/Alizarin red). The percentage of peri-implant tissue repair was analyzed via images obtained by an optical microscope coupled to a digital camera using Leica software and Adobe Photoshop QWin. Data were analyzed statistically with a significance level of 5%. Results: Histomorphometric results showed 97.16% of bone-implant contact for group IV, 89.78% of bone contact for group III, 70.89% for group II and 61.59% of bone contact for group I. The statistical analyses demonstrated significant differences (P < 0.05) among group I and other groups. Conclusion: The results suggest that (a) Ti-30Ta promoted an increase of bone healing and apposition around implant; (b) tranexamic acid favored the stabilization of blood clot and bone formation

Wettability behavior of nanotubular TiO2 intended for biomedical applications

Nanotubes have been subject of studies with regard to their ability to promote differentiation of several cells lines. Nanotubes have been used to increase the roughness of the implant surfaces and to improve bone tissue integration on dental implant. In this study TiO2 nanotube layer prepared by anodic oxidation was evaluated. Nanotube formation was carried out using Glycerol-H2O DI(50-50 v/v)+NH4F(0,5 a 1,5% and 10-30V) for 1-3 hours at 37ºC. After nanostructure formation the topography of surface was observed using field-emission-scanning-microscope (FE-SEM). Contact angle was evaluated on the anodized and non-anodized surfaces using a water contact angle goniometer in sessile drop mode with 5 μL drops. In the case of nanotube formation and no treatment surface were presented 39,1° and 75,9°, respectively. The contact angle describing the wettability of the surface is enhanced, more hydrophilic, on the nanotube surfaces, which can be advantageous for enhancing protein adsorption and cell adhesion.Los nanotubos se han estudiado con respecto a su capacidad para promover la diferenciación de diversos linajes de células. Los nanotubos se han utilizado para aumentar la rugosidad de la superficie de los implantes y mejorar la integración del tejido óseo. En este estudio, TiO2 nanotubos se preparó por oxidación anódica. Los nanotubos fueron formados utilizando glicerol-DI H2O (50/50 v / v) + NH4F (0,5 a 1,5%, y 10-30) durante 1-3 horas a 37 ° C. La topografía de la superficie se evaluó en cuanto a la cantidad, el diámetro y la altura de los nanotubos cultivadas por microscopio electrónico de barrido (SEM) de alta resolución (FEG-SEM). La humectabilidad se evaluó midiendo el ángulo de contacto obtenido en la superficie usando goniómetro 300-F1 (Ramé-Hard Inst.Co) en el modo de la gota sésil con 5 gotas / microlitro. Los resultados mostraron valores medios de 39,1 ° a la superficie cubierta por nanotubos y 75,9 ° en la superficie no anodizado (control). El ángulo de contacto que describe la capacidad de amortiguación de la superficie se incrementó en las superficies de los nanotubos. La mayor hidrofilicidad puede resultar más ventajoso para mejorar la adsorción de proteínas y la adhesión celular.Nanotubos têm sido objeto de estudos no que se refere à sua capacidade de promover a diferenciação de várias linhagens celulares. Nanotubos têm sido utilizados para aumentar a rugosidade da superfície dos implantes e melhorar a integração do tecido ósseo. Neste estudo foi avaliada camada de TiO2 de nanotubos preparada por oxidação anódica. Nanotubos foram formados utilizando glicerol-H2O DI (50-50 v / v) + NH 4 F (0,5 a 1,5% e 10- 30) durante 1-3 horas a 37ºC. A topografia da superfície foi avaliada quanto à quantidade, diâmetro e altura dos nanotubos crescidos por meio de Microscópio Eletrônico de Varredura (MEV) de alta resolução (FEG-SEM). A molhabilidade foi avaliada por meio da mensuração do ângulo de contato obtido na superfície utilizando-se Goniômetro 300-F1 (Ramé-Hard Inst.Co) no modo de gota séssil com 5 gotas/microlitro. Resultados apontaram valores médios de 39,1 ° para superfície recoberta por nanotubos e 75,9° para superfície não-anodizada (controle). O ângulo de contato que descreve a capacidade de umedecimento da superfície mostrou-se aumentado sobre as superfícies de nanotubos. A maior hidrofilicidade pode se mostrar mais vantajosa para melhorar a adsorção de proteínas e adesão celular