Study On The Preparation And Properties Of Bone Collagen Membrane Used For Dental Implant Guided Bone Regeneration

Dental implant technique is a common method for tooth defect repair.Due to the lack of physiological bone resorption caused by lack of teeth and bone tissue defect caused by traumatic tooth loss,the alveolar ridge is often too low,too narrow or partially depressed.This appearance led to the failure of dental implant.With the clinical application of guided bone regeneration(GBR),the above problem is solved.The core of guided bone regeneration technique is the biological membrane of soft tissue into the barrier fibroblast.The performance of biological membrane is the key to guide bone regeneration technique successfully,including good biocompatibility,high mechanical strength,appropriate degradation time etc.According to the performance requirements of the biological membrane and the guidance of tissue engineering principle,we used the new technology of treating porcine pericardium to remove various immune cells and retain the greatest degree based on the natural collagen network structure on the basis of the existing research in the laboratory and the latest research.Then we composited chitosan to improve the biological compatibility of the pericardium and improve the degradation time by crosslinking.Finally we prepared the pericardial collagen membrane for guided bone regeneration in dental implant and tested its performance characterization:(1)In order to optimize the acellular process of porcine pericardium and determine the process parameters of acellular process,we used and improved the process based on pig skin in our laboratory(pretreatment,degreasing,alkali swelling,dealkalize,enzyme softening).Then we applied the process to porcine pericardium by adjusting the reagent concentration and action time.The tensile strength,porosity,degradation time and other physical and chemical properties of acellular porcine pericardium were detected.The results show that with the increase of alkali concentration,enzyme concentration,prolonging the time of enzyme,the porosity of acellular porcine pericardium increased,tensile strength decreased gradually and the degradation time increases with the enzyme concentration decreased gradually and the time of enzyme prolonged gradually.We detected the tensile strength 5.78Mpa,porosity 75.09%and degradation time 1132min of acellular porcine pericardium by 1.1%sodium hydroxide solution with 16h,0.4%pancreatin and 0.6%1398 protease solution with 2h.(2)By the optimization process of acellular porcine pericardium,we composited different concentration chitosan and crosslinking,detecting and analizing the effects of different chitosan composite on the pericardium tensile strength,porosity and degradation time,providing the basis for the preparation of dental implant guided bone regeneration pericardium.The experimental results show that with increasing the amount of chitosan composite,tensile strength,porosity and degradation time of the pericardium were gradually increased,and the data show that the tensile strength,porosity and degradation time can improve obviously and the chitosan plays a good role in bridging the crosslinking process.The optimum composite amount of chitosan was 1%,and the tensile strength is 11.93MPa,porosity is 79.60%and degradation time is 56.5h.The prepared acellular pericardium could better meet the physical and chemical properties of the guided bone regeneration membrane.(3)According to(1)and(2)in the optimization process of acellular porcine pericardium and chitosan composite technology,combined with the performance requirements of guided bone regeneration membrane,we prepared dental implant guided bone regeneration pericardial collagen membrane and the performance of the new prepared pericardial collagen membrane guided bone regeneration related were tested.The results showed that:the pericardium after crosslinking is yellowish,smooth and rough surface is clearly visible,and the surface has no visible impurities;Scanning Electron Microscopy showed that the pericardial collagen membrane surface is dense,fiber arranged closely,the internal structure is loose,the skeleton is composed of a plurality of fine fiber bundles,and fiber bundles have finer-fiber connections,and fiber arranged in mesh structure,pore between fiber bundles,the collagen network has not been destroyed;The thickness of new prepared guided bone regeneration of pericardial collagen membrane thickness is 0.62mm,tensile strength is 12.46MPa,porosity is 79.94%;The simulation in votro results showed that the degradation time was 56.1h and the thickness and porosity of the membrane could meet the requirements of the clinical application of bone regeneration membrane.The tensile strength was more than 10 times than the pure collagen membrane and the mechanical strength was good.