The vital tooth bleaching is impossible by the cloudiness of the tooth enamel outer layer

由于牙釉质外层的浑浊，活体牙齿漂白是不可能的

• 批准号: 17592043
• 负责人: KAWADA Eiji
• 金额: $ 1.86万
• 依托单位: Tokyo Dental College
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17592043/
• 关键词: nano inentatio; bleaching; vital tooth; morphology; hydrogen peroxide; enamel; cross-sectional structure; 硬さ; 歯学; 光沢

Carbamide peroxide and hydrogen peroxide are used as the main agent in vital tooth bleaching. In this study, bovine enamel was immersed in different concentrations of peroxide over differing periods of time to clarify the influence of peroxide treatment. Its influence on cross-sectional morphology and mechanical properties was investigated.Bovine enamel surfaces, from which coronal cementum was removed, were covered with nail varnish, except for a 3x5-mm window on the labial surface. Specimens were then immersed in 10% or 30% carbamide peroxide (CP) or hydrogen peroxide (HP) for 30 or 180 min (n=5, each condition). The specimens were then embedded in epoxy resin and cut at an angle perpendicular to the tooth axis 7 mm from the incisal edge of the tooth. Sectional enamel was finally polished with a 0.05-gm alumina suspension. Nanohardness was determined by using a nanoindentation system. Observation was carried out under scanning electron microscopy. The nanohardness of the enamel treated with either peroxide decreased at 2μm below the outermost enamel surface, but no decrease was observed at 50 tm. Higher concentrations of peroxides caused erosion to a depth of 5μm below the outermost surface, which was deeper than that with a low concentration of peroxide.

过氧化氨基甲酸酯和过氧化氢用作重要牙齿漂白的主要药物。在这项研究中，将牛搪瓷浸入不同浓度的过氧化物中，以阐明过氧化物治疗的影响。研究了它对横截面形态和机械性能的影响。除去冠状胶质的玻璃牙釉质表面被冠状胶质覆盖，除了唇面上的3x5 mm窗口外，还覆盖了指甲清漆。然后将试样浸入10％或30％的氨基甲酸酯（CP）或过氧化氢（HP）30或180分钟（n = 5，每种条件）。然后将样品嵌入环氧树脂中，并以垂直于牙齿轴牙齿的牙齿轴的角度切割，从牙齿的切牙边缘7 mm切割。截面搪瓷最终用0.05 gm氧化铝悬浮液抛光。使用纳米识别系统确定纳米hard。在扫描电子显微镜下进行观察。在最外面的牙釉质表面以下2μm处理，用两种过氧化物处理的牙釉质的纳米核定降低，但在50 Tm处未观察到降低。较高浓度的过氧化物导致侵蚀至最外表面5μm的深度，比过氧化物浓度低的深度要深。

项目成果

Influence of ascorbic acid on bonding of peroxide-affected dentin and 4-META/MMA-TBB resin

• DOI: 10.1007/s00784-006-0071-2
• 发表时间: 2006-12-01
• 期刊: CLINICAL ORAL INVESTIGATIONS
• 影响因子: 3.4
• 作者: Nomoto, S.;Kameyama, A.;Sato, T.
• 通讯作者: Sato, T.

Nanoindentation Study of Bovine Enamel Treated f with Peroxide Solution

过氧化氢溶液处理牛牙釉质的纳米压痕研究

• 发表时间: 2007
• 作者: Ushigome;T;Takemoto;S;Hattori;M;Yoshinari;M;Kawada;E;Oda;Y
• 通讯作者: Y