Almeida Aline Ferreira de, Torre Eliana do Nascimento, Selayaran Maicon Dos Santos, Leite Fábio Renato Manzolli, Demarco Flávio Fernando, Loguercio Alessandro Dourado, Etges Adriana
Department of Semiology and Clinics, School of Dentistry, Universidade Federal de Pelotas, Pelotas, RS, Brazil.
School of Dentistry, Department of Restorative Dentistry, School of Dentistry, Universidade Federal de Pelotas, Pelotas, RS, Brazil.
Braz Oral Res. 2015;29. doi: 10.1590/1807-3107BOR-2015.vol29.0021. Epub 2015 Jan 13.
Dental bleaching has become one of the most frequently requested esthetic treatments in dental offices. Despite the high clinical success observed with this procedure, some adverse effects have been reported, including a potential for developing premalignant lesions, root resorption and tooth sensitivity, especially when misused. The aim of this study was to evaluate the genotoxic response using a micronucleus (MN) assay, after the application of two concentrations of carbamide peroxide. Thirty-seven patients were divided into two groups and randomly received either a 10% carbamide peroxide (CP) (19) or a 16% carbamide peroxide (18) concentration for 21 days in individual dental trays. Gingival margin cells were collected immediately before the first use (baseline), and then 15 and 45 days after baseline. The cells were placed on a histological slide, stained by the Feulgen technique, and evaluated by an experienced blinded examiner. One thousand cells per slide were counted, and the MN rate was determined. The two groups were analyzed by the Wilcoxon rank-sum test and the Kruskal-Wallis equality-of-populations rank test. A slight increase in MN was observed for both groups, in comparison with the baseline, at 15 days. However, no difference was observed between the two groups (10% and 16%), at either 15 or 45 days (p = 0.90). When bleaching is not prolonged or not performed very frequently, bleaching agents containing carbamide peroxide alone will not cause mutagenic stress on gingival epithelial cells.
牙齿美白已成为牙科诊所中最常被要求的美容治疗之一。尽管该程序在临床上取得了很高的成功率，但仍有一些不良反应被报道，包括发生癌前病变、牙根吸收和牙齿敏感的可能性，尤其是在滥用时。本研究的目的是在应用两种浓度的过氧化脲后，使用微核（MN）试验评估遗传毒性反应。37名患者被分为两组，并随机在单独的牙托中接受10%过氧化脲（CP）（19人）或16%过氧化脲（18人）浓度的治疗，持续21天。在首次使用前（基线）、基线后15天和45天立即收集牙龈边缘细胞。将细胞置于组织学载玻片上，采用Feulgen技术染色，并由一位经验丰富的盲法检查者进行评估。每张载玻片计数1000个细胞，并确定微核率。两组通过Wilcoxon秩和检验和Kruskal-Wallis总体秩相等检验进行分析。与基线相比，两组在15天时微核均略有增加。然而，在15天或45天时，两组（10%和16%）之间未观察到差异（p = 0.90）。当美白不延长或不频繁进行时，仅含过氧化脲的美白剂不会对牙龈上皮细胞造成诱变应激。
