ABSTRACT
Abstract Tissue engineering suggests different forms to reconstruct tissues and organs. One of the ways is through the use of polymeric biomaterials such as poly(L-lactic acid) (PLLA). PLLA is a recognized material in tissue engineering due to its characteristics as biocompatibility and bioresorbability. In this work PLLA fibrous membranes were produced by a simple technique known as rotary jet spinning. The rotary jet spinning consists of fibrous membranes production, with fibers of scale nano/micrometric, from a polymeric solution through the centrifugal force generated by the equipment. The membranes formed were subjected to preliminary in vitro assays to verify the cytotoxicity of the membranes made in contact with the cells. Direct cytotoxicity assays were performed through the MTT, AlamarBlue® and Live/Dead® tests, with fibroblastic and osteoblastic cells. The results obtained in this study showed that PLLA membranes produced by rotary jet spinning showed promising results in the 24-hours contact period of the cells with the PLLA fibrous membranes. The information presented in this preliminary study provides criteria to be taken in the future procedures that will be performed with the biomaterial produced, aiming at its improvement.
Subject(s)
Biocompatible Materials , Lactic Acid , Tissue Engineering/methods , In Vitro Techniques/instrumentationABSTRACT
PURPOSE: To investigate the osseointegration properties of prototyped implants with tridimensionally interconnected pores made of the Ti6Al4V alloy and the influence of a thin calcium phosphate coating. METHODS: Bilateral critical size calvarial defects were created in thirty Wistar rats and filled with coated and uncoated implants in a randomized fashion. The animals were kept for 15, 45 and 90 days. Implant mechanical integration was evaluated with a push-out test. Bone-implant interface was analyzed using scanning electron microscopy. RESULTS: The maximum force to produce initial displacement of the implants increased during the study period, reaching values around 100N for both types of implants. Intimate contact between bone and implant was present, with progressive bone growth into the pores. No significant differences were seen between coated and uncoated implants. CONCLUSION: Adequate osseointegration can be achieved in calvarial reconstructions using prototyped Ti6Al4V Implants with the described characteristics of surface and porosity. .
Subject(s)
Animals , Male , Ceramics/therapeutic use , Implants, Experimental , Osseointegration/physiology , Skull/surgery , Titanium/therapeutic use , Calcium Phosphates , Coated Materials, Biocompatible , Ceramics/chemistry , Materials Testing , Microscopy, Electron, Scanning , Rats, Wistar , Reproducibility of Results , Spectrometry, X-Ray Emission , Surface Properties , Time Factors , Treatment Outcome , Titanium/chemistryABSTRACT
Até o aparecimento da tomografia computadorizada, e principalmente, da ressonância magnética, os métodos diagnósticos complementares eram bem limitados na avaliação e, sobretudo na extensão da lesão, tendo então a RM sido preconizada como método de escolha na avaliação neurorradiológica. Exames de imagem como ventriculografia, pneumoencefalografia e radiografia convencional foram deixados de lado em prol destes métodos mais recentes, ao mesmo tempo em que a arteriografia ganhou indicações mais precisas e limitadas. O estudo da espectroscopia permite diagnósticos mais precoses e caracterização de bordas lesionais, com finalidade extremamente prática para neurocirurgiões. É ainda possível determinar e qualificar a perda neuronal, funcionando como importante ferramenta diagnóstica na detecção e prognóstico de doenças neurológicas.
Before the appearance of computed tomography and specially magnetic resonance imaging, complementary exams were limited in the extension's lesion evaluation, so the MRI have been chosen the gold standard for imaging the neurological diseases. Ventriculography, pneumoencefalography and conventional X rays were destined to be forgotten while arteriography secured indications in precise and limited cases. Spectroscopy gives early diagnosis and defines lesion's borders, providing practical information for neurosurgeons. It is also possible to qualify the neuronal loss, representing as an important tool in detection and prognosis for neurological diseases.