Khoroushi Maryam, Ghazalgoo Ali
Dental Materials Research Center and Department of Operative Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran.
Indian J Dent Res. 2013 Jan-Feb;24(1):87-92. doi: 10.4103/0970-9290.114961.
Tooth sensitivity is common after vital tooth bleaching. The aim of this study is to evaluate the effect of a desensitizing agent on shear bond strength of composite resin to bleached enamel; and determine whether a delay of one or two weeks in bonding procedure is sufficient subsequent to bleaching/desensitizer regimen.
Buccal enamel surfaces of ninety-six human sound molars were prepared and divided into eight groups. The surfaces of specimens in Group 1 as negative control group were bonded by composite resin using the single bond adhesive. Specimens in Groups 2-4 were bleached with an at-home bleaching agent (Daywhite ACP). Relief ACP desensitizing gel alone was applied in Group 5. In Groups 6-8, specimens were bleached same as in Group 2 and relief ACP desensitizing gel was applied same as in Group 5 subsequent to each bleaching session. Composite cylinders were bonded after 24 h, 7 days and 14 days in Groups 2-4, respectively, and also in Groups 6-8, respectively. The shear bond strengths of the cylinders were tested and data was analyzed using two-way ANOVA and Tukey test (α = 0.05).
The results showed that bleaching and bleaching/desensitizer regimens significantly reduced the bond strength of composite resin to enamel. However, desensitizer alone did not reduce bond strength. No statistically significant differences were found between bleaching and bleaching/desensitizer regarding bond strength.
Bleaching or bleaching/desensitizer treatment significantly decreases bond strength of composite resin to enamel. In both regimens, adhesive bonding is recommended after two weeks.
活髓牙漂白后牙齿敏感很常见。本研究旨在评估一种脱敏剂对复合树脂与漂白釉质之间剪切粘结强度的影响；并确定在漂白/脱敏方案后，粘结程序延迟一或两周是否足够。
制备96颗健康人磨牙的颊面釉质表面并分为八组。第1组作为阴性对照组，其标本表面使用单键粘合剂通过复合树脂粘结。第2 - 4组的标本用家用漂白剂（Daywhite ACP）进行漂白。第5组仅应用Relief ACP脱敏凝胶。在第6 - 8组中，标本的漂白方式与第2组相同，且每次漂白后应用Relief ACP脱敏凝胶的方式与第5组相同。第2 - 4组以及第6 - 8组分别在24小时、7天和14天后粘结复合圆柱体。测试圆柱体的剪切粘结强度，并使用双向方差分析和Tukey检验（α = 0.05）分析数据。
结果表明，漂白以及漂白/脱敏方案显著降低了复合树脂与釉质之间的粘结强度。然而，单独使用脱敏剂并未降低粘结强度。在粘结强度方面，漂白和漂白/脱敏方案之间未发现统计学上的显著差异。
漂白或漂白/脱敏处理会显著降低复合树脂与釉质之间的粘结强度。在这两种方案中，建议在两周后进行粘结。
