Develop Material For Palatal Implant Visualized In X-ray And Property Investigation

Objective:Hydroxyapatite and Poly(lactide-co-trimethylene carbonate)applied widely in many subjects with well biocompatibility.A preliminary study was carried out to develop cylindrical palatal implants wihich is made of Hydroxyapatite and Poly(lactide-co-trimethylene carbonate) , adding barium sulphate(BaSO4).To investigate the effect of fibrosis and visualization.Another preliminary study was also carried out to discuss the character and degradation ability. In order to develop a new kind of palatal implants.Methods:Cylindrical palatal implants of HA, PLA and adding BaSO4 were fabricated by a organo- molding technique. Successive studies were done in such ways:1 .Three palatal implants were implanted into muscle parallel of 18 normal white rabbits. The samples were examined by X-ray to evaluate the effectiveness of visualization.2.White rabbits was implanted with HA-P and Pillar. The specimens were harvested in 2,4,8,12 weeks. The samples were examined by histology and Image Tool for Windows version 3.0 to evaluate the effectiveness of fibrosis.3. HA-P were examined by scanning electronic microscope (SEM) to evaluate the character. The samples were immersed to the distilled water and phosphate buffer solution. Different methods such as pH, mass lost were employed to study the degradation in vitro. Results:1. This palatal implants material can be displayed precisely under X-ray. During the experiment, there were not obvious inflammations found.2. Histological analysis demonstrated thicker fibrosis with development in all specimens. At the beginning, more fibrosis was observed in PET. At the end of the experiment, the formation of capsule in PET ended up with a thickness of (18±4.1)μm, slightly thicker than that of HA-P (17±4.4)μm (P>0.05). There were no obvious distinction between two groups.3. SEM photomicrographs of the HA-P revealed extensive pores which were roughly spherical in shape and evenly distributed throughout. The pores appeared connected to each other, forming an interconnected network Results obtained from measurement indicated a porosity of about 80%, and a controllable pore size in range of 500μm. During the process, the pH and mass display a gradual descent However, the pH indicator maintained a fairly stable range near to original enviroment. In addition,there was slowing decrease in mass relative stability compare to beginning.Conclusion:1. This palatal implants material can be displayed clearly under X-ray. The effectiveness can be maintenance in long-term.2. PET and HA-P stiffen the soft palate equivalency.3. HA-P possesses high porosities and well biostability. Basically meet the requirements of clinical application. It can be an ideal composite scaffold for tissue engineering and palatal implant.