School of Dentistry, University of Ribeirão Preto, Ribeirão Preto, Brazil.
Microsc Res Tech. 2011 Mar;74(3):244-50. doi: 10.1002/jemt.20895.
It remains unclear as to whether or not dental bleaching affects the bond strength of dentin/resin restoration.
To evaluated the bond strength of adhesive systems to dentin submitted to bleaching with 38% hydrogen peroxide (HP) activated by LED-laser and to assess the adhesive/dentin interfaces by means of SEM.
Sixty fragments of dentin (25 mm²) were included and divided into two groups: bleached and unbleached. HP was applied for 20 s and photoactivated for 45 s. Groups were subdivided according to the adhesive systems (n = 10): (1) two-steps conventional system (Adper Single Bond), (2) two-steps self-etching system (Clearfil standard error (SE) Bond), and (3) one-step self-etching system (Prompt L-Pop). The specimens received the Z250 resin and, after 24 h, were submitted to the bond strength test. Additional 30 dentin fragments (n = 5) received the same surface treatments and were prepared for SEM. Data were analyzed by ANOVA and Tukey's test (α = 0.05).
There was significant strength reduction in bleached group when compared to unbleached group (P < 0.05). Higher bond strength was observed for Prompt. Single Bond and Clearfil presented the smallest values when used in bleached dentin. SEM analysis of the unbleached specimens revealed long tags and uniform hybrid layer for all adhesives. In bleached dentin, Single Bond provided open tubules and with few tags, Clearfil determined the absence of tags and hybrid layer, and Prompt promoted a regular hybrid layer with some tags.
Prompt promoted higher shear bond strength, regardless of the bleaching treatment and allowed the formation of a regular and fine hybrid layer with less deep tags, when compared to Single Bond and Clearfil.
目前尚不清楚牙齿漂白是否会影响牙本质/树脂修复的粘结强度。
评估 38%过氧化氢（HP）经 LED 激光激活漂白后对牙本质粘结强度的影响，并通过 SEM 评估粘结/牙本质界面。
共纳入 60 个牙本质碎片（25mm²），分为两组：漂白组和未漂白组。HP 作用 20s 后，经 LED 激光激活 45s。根据粘结系统进一步分组（n = 10）：（1）两步法传统系统（Adper Single Bond），（2）两步法自酸蚀系统（Clearfil SE Bond），（3）一步法自酸蚀系统（Prompt L-Pop）。所有标本均涂布 Z250 树脂，24h 后进行粘结强度测试。另外 30 个牙本质碎片（n = 5）接受相同的表面处理，并准备进行 SEM 分析。数据采用 ANOVA 和 Tukey 检验（α = 0.05）进行分析。
与未漂白组相比，漂白组的粘结强度显著降低（P < 0.05）。Prompt 组的粘结强度最高，Single Bond 和 Clearfil 组在漂白牙本质中的粘结强度最小。未漂白标本的 SEM 分析显示，所有粘结剂均有长的粘结带和均匀的混合层。在漂白牙本质中，Single Bond 呈现开放的小管，粘结带较少，Clearfil 无粘结带和混合层，Prompt 则形成有规则粘结带和少量小管的混合层。
与 Single Bond 和 Clearfil 相比，Prompt 无论在漂白处理下均能提供更高的剪切粘结强度，并形成规则、精细的混合层，其粘结带深度较小。
