Mechanism of Ion Permeability and Recrystallization of Calcium Phosphate Bio-materials in Dentinal tubules

• Main Authors: Wei-Ching Yen, 顏煒慶
• Other Authors: 林俊彬
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/74799117930480624999

碩士 === 國立臺灣大學 === 臨床牙醫學研究所 === 102 === There are various kinds of commercial products claimed to be able to relieve the symptoms of dentin hypersensitivity, but none of the products have immediate and long-lasting effects. Our previous study showed that gelatin-templated calcium mesoporous silicate (GCMS) with 30% H3PO4 could efficiently occlude dentinal tubules by precipitation thus have great potential in treating dentin hypersensitivity. Also, GCMS with 30% H3PO4 could show great biocompatibility through dentin disc barrier. To be an idea dental material, it is important to find out the mechanism of ion permeability and recrrstaliiizaton of calcium phosphate biomaterial in dentinal tubule. Therefore, research goals of the present study is: 1. To find out the mechanism of ion permeability and recrystallization of CaCO3@ Mesoporous Silica-Phosphate in dentinal tubule 2. To find out the effect of time factor to the recrystallization of CaCO3@ Mesoporous Silica-Phosphate in dentinal tubule 3. To find out the source of calcium in the recrystallization in dentinal tubule 4. To evaluate the efficacy in vitro by animal study This research comprised of four parts. First, we used transwell dentin disc model and ion chromatography to measure the ion permeability of GCMS / 30% H3PO4 , SrCO3 mesoporous silicates / 30% H3PO4 , 30 % H3PO4 and calcium hydroxide. The second part we applied GCMS mixed with 30% H3PO4 in the dentin disc and observed the recrystallization in the dentinal tubule by SEM at four different time points. Furthermore, EDS was used to analyze the component of recrystallization. At third part, we applied strontium mesoporous silicates mixed with 30% H3PO4 in the dentinal tubule to find out the source of calcium in the recrystallization by using EDS. Fourth, we used animal study to evaluate the efficacy of GCMS / 30% H3PO4 , SrCO3 mesoporous silicates / 30% H3PO4 in vivo. In conclusion: （1）Calcium ion was not easily penetrate through the dentin barrier .PO43- could be a pilot to usher Ca2+ into dentinal tubules induce recrystallization.（2）The length of the recrystallization and the placement period of material are in direct proportion. (3) Partial calcium ion in the recrystallization was from the tooth. (4) GCMS/ 30% H3PO4 , SrCO3 mesoporous silicates / 30% H3PO4 had great efficacy in vivo.