Aggarwal V, Bhasin S S
Oper Dent. 2018 Sep/Oct;43(5):E243-E252. doi: 10.2341/17-306-L. Epub 2018 Jun 28.
The aim of the present study was to evaluate the effect of the application of calcium silicate materials (CSMs), after acid etching, on the longevity of the hybrid layer and marginal adaptation of composite restorations.
Eighty human permanent molars received an intrapulpal pressure of 15 cm HO. Sixty teeth received a mesial proximal slot preparation with the gingival margin extending 1 mm below the cemento-enamel junction. The samples were divided into two groups. Group 1 received restorations using two types of etch-and-rinse adhesives: ethanol based (Single Bond, 3M ESPE, St Paul, MN, USA) and acetone based (Prime & Bond NT, Dentsply, DeTrey GmbH, Germany). In group 2 samples, a commercially available CSM (ProRoot MTA) was allowed to set before grinding and placing into a distilled water solution. This solution was applied on the cavity floor after acid etching. The surface was washed after 30 seconds followed by application of adhesives and restorations as in group 1. The samples were stored in phosphate-buffered saline for six months, maintaining the intrapulpal pressure. An epoxy replica was made, and the marginal adaptation was evaluated using scanning electron microscopy. The percentage of continuous margin (CM) was recorded for each group. Another 20 samples were used for hybrid layer evaluation. The crowns were ground to expose dentin. Intrapulpal pressure was applied. The samples were divided into two groups and restored similar to samples restored for marginal adaptation evaluation. The samples were longitudinally cut in 1-mm slices. The slices were stored under 15 cm of phosphate-buffered saline to simulate the pulpal pressure. After six months, the adhesive interface was evaluated using a scanning electron microscope. Statistical analysis was done with two-way analysis of variance with Holm-Sidak's correction for multiple comparisons.
Application of CSMs improved the marginal adaptation values in both adhesive groups. In group 1, there were areas of incomplete penetration of resins along with evidence of partial degradation of resin tags. Samples receiving CSM application after acid etching demonstrated long and regular resin tags with very few signs of degradation.
Application of CSMs after acid etching can be a potential avenue in preserving the resin-dentin bonds.
本研究的目的是评估在酸蚀后应用硅酸钙材料（CSMs）对混合层寿命及复合树脂修复体边缘适应性的影响。
80颗人类恒牙施加15 cm水柱的牙髓腔内压力。60颗牙齿制备近中邻面洞，龈缘延伸至牙骨质-釉质界下方1 mm处。样本分为两组。第1组使用两种酸蚀冲洗型粘结剂进行修复：乙醇基（Single Bond，3M ESPE，美国明尼苏达州圣保罗）和丙酮基（Prime & Bond NT，登士柏，德国德特雷有限公司）。在第2组样本中，一种市售的CSM（ProRoot MTA）在研磨并置于蒸馏水溶液中之前先凝固。酸蚀后将该溶液涂于洞底。30秒后冲洗表面，然后像第1组一样应用粘结剂和修复体。样本在保持牙髓腔内压力的情况下于磷酸盐缓冲盐水中储存6个月。制作环氧树脂复制品，使用扫描电子显微镜评估边缘适应性。记录每组连续边缘（CM）的百分比。另外20个样本用于混合层评估。磨除牙冠以暴露牙本质。施加牙髓腔内压力。样本分为两组并进行修复，修复方式与用于边缘适应性评估的样本相似。样本纵向切成1 mm厚的切片。切片储存在15 cm深的磷酸盐缓冲盐水中以模拟牙髓压力。6个月后，使用扫描电子显微镜评估粘结界面。采用双向方差分析并进行Holm-Sidak校正以进行多重比较的统计分析。
CSMs的应用提高了两个粘结剂组的边缘适应性值。在第1组中，存在树脂不完全渗透区域以及树脂微突部分降解的证据。酸蚀后应用CSM的样本显示出长且规则的树脂微突，降解迹象极少。
酸蚀后应用CSMs可能是保存树脂-牙本质粘结的一个潜在途径。
