Remineralization Effects of Calcium Phosphate Based Paste for Tooth Enamel

• Published in: The Japanese Journal of Conservative Dentistry Vol. 59; no. 1; pp. 58 - 64
• Main Authors: Shinji, SHIMODA, Yuka, ASADA, Yasuko, MOMOI, Takatsugu, YAMAMOTO, Misao, ISHIKAWA, Toshie, CHIBA
• Format: Journal Article
• Language: Japanese
• Published: The Japanese Society of Conservative Dentistry 2016; 特定非営利活動法人 日本歯科保存学会
• Subjects: apatite; DCPA; phosphate based paste; remineralization; TTCP; アパタイト; リン酸カルシウム系ペースト; 再石灰化
• ISSN: 0387-2343; 2188-0808
• DOI: 10.11471/shikahozon.59.58

Purpose: The purpose of the present study was to clarify the remineralization effects for tooth enamel using calcium phosphate based paste (AP paste) containing tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) that was designed using the principle of calcium phosphate cement. The study compared control and experimental groups in terms of the Ca/P ratio and crystal growth using artificially demineralized tooth enamel.  Methods: Extracted human permanent teeth were used in this study. Enamel samples having experimental windows were demineralized with 50 mmol/l acetic acid for three days. AP paste was then applied to the windows three times a day for two weeks. The samples were embedded in epoxy resin and sectioned. The highly polished sections were observed by back-scattered electron imaging. Semi-quantitative analysis was also performed for Ca, P and F elements using an electron probe micro analyzer (EPMA). The samples were evaluated from crystal morphological observations using transmission electron microscopy (TEM).  Results: EPMA analysis confirmed that Ca, P and F elements obviously percolated into and accumulated in enamel. The Ca/P ratio of the demineralized and the AP paste applied enamel were 1.38-1.42 and 1.57-1.65, respectively. Apparent crystal growth was observed in demineralized enamel crystals, indicating remineralization of demineralized tooth enamel tissue.  Conclusion: TTCP and DCPA in the paste released calcium and phosphate ions, and the ions clearly promoted crystal growth in demineralized tooth enamel. Thus, it is considered that the AP paste would strongly promote tooth enamel calcification as a biocompatible material.