Development of bioactive materials for root canal therapy: crystallization mechanisms and occlusion of lateral canals and ramifications

• Main Authors: Yen-Yi Chen, 陳嬿伊
• Other Authors: 林俊彬
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/76j6u3

碩士 === 國立臺灣大學 === 臨床牙醫學研究所 === 104 === Our previous study showed that gelatin-templated calcium mesoporous silicate (GCMS) mixed with 30% H3PO4 could efficiently occlude dentinal tubules under pulpal pressure in beagle in vivo by precipitation of 90 μm calcium phosphate crystal. Whether there is same effect on root canal system, especially on lateral canal and apical ramifications, remains unknown. Besides, the silicate content may become concerned in root canal. Development of new bioactive material to precipitate in dentinal tubules is therefore another research goal. After review some literature, we assumed that monocalcium phosphate monohydrate (MCPM) and β-tricalcium phosphate (β-TCP) have potentials as GCMS. Therefore, research goals of the present study is: First to observe different pH value in precipitation of MCPM/β-TCP mixture, and evaluation time factor in precipitation of MCPM/β-TCP mixture on dentinal tubules. At the same time, we modified inner surface of dentinal tubules and evaluation bioactive material on occlusion. Then evaluation GCMS, MCPM/β-TCP and DP-Bioglass in root canal system of human tooth in vitro. The last part was evaluated the efficacy in vivo by animal study This research comprised of five parts. First, we use different pH value of MCPM/β-TCP mixture place on dentin disc to observe precipitation by SEM and choice the most proper ratio for following study. The second part, we compare time factor and relation with precipitation in dentinal tubules. The third one is to modified inner surface of glycosaminoglycan in dentinal tubules by hyaluronidase and sodium hypochlorite and we evaluate the effect. Fourth, apply bioactive material including GCMS, MCPM/β-TCP and DP-Bioglass in root canal system of human tooth in vitro and observe by SEM. The final part we used animal study to evaluate the efficacy of GCMS, MCPM/β-TCP and DP-Bioglass in vivo. In conclusion: 1. MCPM/β-TCP can precipitate in dentinal tubule. Using the mole ratio of 1:1 and pH value 3.5 - 4, the precipitation reaches 70μm. The longer placed time is related to the better occlusion density and length. 2. Hyaluronidase and sodium hypochlorite can modify dentinal tubule and improve the depth of bioactive material precipitation in dentinal tubules. 3. GCMS, MCPM/β-TCP and DP-Bioglass can precipitate in the apical third of dentinal tubule and lateral canal in human tooth in vitro. 4. MCPM/β-TCP can also precipitation in apical third of dentinal tubule in vivo.