In vitro stimulation of osteoblasts using capacitive interdigitated electrodes to improve implant osseointegration

• Autor(a) principal: Sousa, Bárbara Mamede de
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/25373
• topic: Estimulação eletromagnética; Estimulador capacitivo de padrão interdigitado; Osteoblastos; Efeitos osteocondutores; Osseointegração

Given the growing global incidence of musculoskeletal disorders and the rising frequency of several prosthetic revision surgeries, it becomes crucial to develop new active prostheses that comprise controllable stimuli and allow for osseointegration, avoiding failures in implant fixation. Ideally, active prostheses will incorporate biophysical actuation systems that promote osteoconduction and osseointegration. These could apply electromagnetic stimuli to surrounding tissues, since the bone presents natural endogenous electric currents. Considerable research already revealed positive effects of exogenous electric and/or magnetic stimuli on bone remodelling. However, stimulation systems for incorporation in instrumented active bone implants are not yet validated. A new concept of capacitive cosurface stimulator was developed by our group, with several electrode architectures designed and tested – including the interdigitated pattern. The present study intends to assess the osteoconductive effects of the interdigitated electrode architecture in vitro, using high frequency electric stimulation. For such purpose, the proliferation and differentiation of pre-osteoblastic MC3T3 cells were experimentally assessed after electric stimulation of 0.7 V.mm-1 and 60 kHz, 30 min/day for 28 days, using the thin interdigitated pattern architecture (0.1 mm thickness). The results show the tested stimulation setup increases collagen production and deposition, alkaline phosphatase activity and matrix mineralization levels. The obtained data will be compared with previous results to perform a systematic evaluation that correlates several stimuli parameters (electrode design, electric field intensity and frequency). This work drives future studies on the in vivo efficacy of high frequency stimuli delivered by these novel thin capacitive stimulators inserted in instrumented active implants, in what could be a future personalized therapeutic actuation system.