Papers by Keyword: Calcium Phosphate Bioceramics

Abstract: Tympanoplasty is the reference for cholesteatoma treatment in ear, nose, and throat (ENT surgery), with the realization of a closing technique, which preserves the external auditory canal. An insufficient pneumatisation is an element favoring the occurrence and recurrence of cholesteatoma. In a prospective clinical pilot study, we have realized the reconstruction of the mastoid cortical bone by a Micro Macroporous Biphasic Calcium Phosphate bioceramics disks (MBCPTM Biomatlante France) using the closed technique, in order to maintain or increase the mastoid pneumatisation. Eleven patients were used for this study, and some of them have a sample collection for histomorphometry and histopathological analysis. Bone regeneration at the expense of the bioceramic was observed. The size and shape of the disk was not preserved due to the large resorption and bone ingrowth at the expense of the implant. However 6 patients presented cholesteatoma recurrence. The MBCPTM disks are able to reconstruct the mastoid cortical and maintain the mastoid pneumatisation contrarily to the technique of filling the mastoid cavity. However, the high rate of cholesteatoma recurrence observed in our study, confirmed the interest to fill mastoid that suppress airspace posterior cavities.

Abstract: This paper reports on the research into multiphase bone substitutes carried out by laboratories from the ‘Pays de la Loire’ region in France. This collaborative research was funded by both the French Government and the Regional Council in the period 2000-2007. Calcium phosphate bioceramics, polymers and combinations have been developed as bone substitutes for various maxillofacial and orthopaedic applications. These bone substitutes should support and regenerate bone tissue and resorb after implantation. In the bone tissue engineering area, they have been combined with autologous bone marrow cells or bioactive factors. The bone substitutes were tested in various animal models mimicking clinical situations or under pathological conditions (osteoporosis). In order to complete our research, the multiphase materials were also evaluated in clinical trials.

Abstract: In order to improve the bioactivity of calcium phosphate bioceramics, biphasic HA/β-TCP (BCP) bioceramics were prepared by the microwave sintering and the microwave plasma sintering. Bone-like apatite formation of the resulting samples was investigated in simulated body fluid (SBF). The samples were also implanted in dorsal muscles of healthy dogs for 1.5and 3 months. All samples after taking out were examined by histological observation. Bone formation in different sintering ways and temperatures was investigated in details. Better osteoinductivity was found in samples sintered by the microwave and microwave plasma instead of the conventional furnace, as well as by lower temperature (1050 oC) instead of higher temperature (1150 oC). It accounts for that the increase in degradability of materials sintered by microwave and microwave plasma or lower temperature leads to the better of bone-like apatite formation and bone formation due to fine grains and lower crystallinity.