RESUMO
Introduction: Ti6Al4V titanium alloy is widely used in producing orthopedic and maxillofacial implants, but drawbacks include high elastic modulus, poor osseointegration performance, and toxic elements. A new medical titanium alloy material with better comprehensive performance is urgently needed in the clinic. Methods: Ti10Mo6Zr4Sn3Nb titanium alloy (referred to as Ti-B12) is a unique medical ß titanium alloy material developed by us. The mechanical properties of Ti-B12 depict that it has advantages, such as high strength, low elastic modulus, and fatigue resistance. In our study, the biocompatibility and osseointegration properties of Ti-B12 titanium alloy are further studied to provide theoretical guidance for its clinical transformation. Results and Discussion: The titanium alloy Ti-B12 displays no significant effect on MC3T3-E1 cell morphology, proliferation, or apoptosis in vitro. Neither Ti-B12 titanium alloy nor Ti6Al4V titanium alloy depicts a significant difference (p > 0.05); Ti-B12 material extract injected into the abdominal cavity of mice does not cause acute systemic toxicity. The skin irritation test and intradermal irritation test reveal that Ti-B12 does not cause skin allergic reactions in rabbits. Compared to Ti6Al4V, Ti-B12 titanium alloy material has more advantages in promoting osteoblast adhesion and ALP secretion (p < 0.05). Although there is no significant difference in OCN and Runx2 gene expression between the three groups on the 7th and 14th days of differentiation induction (p > 0.05), the expression of Ti-B12 group is higher than that of Ti6Al4V group and blank control group. Furthermore, the rabbit in vivo test present that 3 months after the material is implanted in the lateral epicondyle of the rabbit femur, the Ti-B12 material fuses with the surrounding bone without connective tissue wrapping. This study confirms that the new ß-titanium alloy Ti-B12 not only has low toxicity and does not cause rejection reaction but also has better osseointegration performance than the traditional titanium alloy Ti6Al4V. Therefore, Ti-B12 material is expected to be further promoted in clinical practice.
RESUMO
A estabilidade primária dos implantes está intimamente relacionada à macro-geometria dos implantes na medida que pode aumentar o contato íntimo entre o biomaterial e a estrutura óssea. O objetivo do presente estudo foi avaliar a influência da macro-geometria na estabilidade primária dos implantes. Foram utilizados dois tipos de implantes, um cilíndrico e com rosca única (grupo controle) e outro com conicidade apical e três tipos de roscas (grupo teste). Os implantes foram instalados por três operadores em osso bovino fresco. Cada profissional fez a instalação de oito implantes (4 teste e 4 controle) em osso bovino. Os parâmetros avaliados foram: torque de inserção, frequência de ressonância e torque de remoção. A análise dos resultados permitiu a detecção de que os torques de inserção foram maiores no grupo teste (p < 0,05). Não foi observada influência do operador nas variáveis analisadas. Pode-se então concluir que a macro-geometria dos implantes do grupo teste favoreceu a estabilidade primária do implante.
The primary stability of implants is related to implant geometry since it can raise the intimate contact between biomaterial and bone structure. The aim of the present study was to evaluate the influence of implant geometry on primary stability. It was used two types of implants, one cylindrical and with an unique thread (control group) and another tapered with three types of threads (test group). Implants were placed by three professionals in bovine bone. Each operator installed eight implants (4 test and 4 control). The parameters analyzed were: inserting torque, unscrewing torque and resonance frequency. As results it was detected that insertion torque was higher in the test group (p < 0,05). It was not observed influence of the operator in the parameters analyzed. Thus, it can be concluded that geometry of implants in the test group improved implant primary stability.
