- 學位論文
研發根管治療用生醫活性材料:結晶機制與封閉側根管及分支
Development of bioactive materials for root canal therapy: crystallization mechanisms and occlusion of lateral canals and ramifications
摘要
本團隊之前的研究顯示以明膠為模板的含碳酸鈣中孔洞二氧化矽複合材料 (簡稱中孔洞鈣矽材料,GCMS) 與 30%磷酸調拌後，置於活體有牙髓腔靜水壓的牙本質上，可於牙本質小管內產生超過90μm的緻密結晶。於牙本質小管的成功經驗，讓本研究團隊開始思索這種中孔洞鈣矽材料是否能夠更進一步於根管系統內，尤其是側根管和根尖分岔，產生相同結果。另外因為中孔洞鈣矽材料含有矽，如果置於根管系統內不會因為再結晶而消失，若有其他不含矽的生醫活性材料能達到類似的牙本質小管再結晶效果亦是一大研究重點。經過文獻回顧發現一水磷酸二氫鈣(MCPM)與三鈣磷酸鹽(β-TCP)混合製劑可產生鈣磷結晶且用於骨頭修復已有多年。 因此本團隊進行以下的實驗: 首先觀察一水磷酸二氫鈣(MCPM)與三鈣磷酸鹽(β-TCP)混合製劑之不同酸鹼值於牙本質小管內再結晶，並且觀察MCPM/β-TCP混合製劑之時間長短對牙本質小管封閉效果，同時想藉由改變牙本質小管內層的醣聚醣胺結構對於生醫材料於牙本質小管封閉效果是否有所影響。進行離體人類牙齒根管系統實驗，評估生醫材料於牙齒根管系統的結晶狀態。最後進行動物實驗,以評估生醫材料在活體根管系統中的效用性。 第一部分以不同酸鹼值之MCPM/β-TCP混合製劑於牙本質試片上塗抹，再以電子顯微鏡觀察再結晶之情況，藉以篩選出適合後續實驗之組別。 第二部分將MCPM/β-TCP混合製劑塗抹放置於牙本質試片上之不同時間，比較時間因素對於再結晶之關係。 第三部分利用透明質酸酶與次氯酸鈉改變牙本質小管內層的醣聚醣胺結構，再分別塗抹上GCMS與MCPM/β-TCP混合製劑進行觀察。 第四部分將GCMS/磷酸製劑、MCPM/β-TCP製劑與生醫玻璃材料等三種生醫材料置於備製後離體人類牙齒之根管系統內，再以電子顯微鏡觀察側根管與根尖分岔再結晶之情況。 第五部分則進行動物實驗以評估GCMS/磷酸製劑、MCPM/β-TCP製劑與生醫玻璃材料等三種生醫材料在活體的效用性。 結論： 1. MCPM/β-TCP混合製劑於牙本質試片能形成再結晶，可有效封閉牙本質小管。其中莫耳比1:1，酸鹼值在3.5~4之混合製劑可在不明顯破壞牙本質結構下於牙本質小管內達到深度70μm的再結晶。材料放置時間與再結晶長度呈現正相關。 2. 透明質酸酶與次氯酸鈉可改變牙本質小管內層的醣聚醣胺結構，增進GCMS與MCPM/β-TCP混合製劑於牙本質小管內再結晶的深度。 3. GCMS、MCPM/β-TCP以及生醫玻璃材料在離體人類牙齒根管系統內可於側根管與根尖三分之一處牙本質小管內產生再結晶。 4. 於活體根管系統內MCPM/β-TCP混合製劑可於根尖三分之一處牙本質小管內產生再結晶。
並列摘要
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.