Kihn P W, Barnes D M, Romberg E, Peterson K
Department of Restorative Dentistry, Baltimore College of Dental Surgery, Dental School, University of Maryland, USA.
J Am Dent Assoc. 2000 Oct;131(10):1478-84. doi: 10.14219/jada.archive.2000.0061.
Agents with carbamide peroxide, or CP, in various concentrations are widely prescribed for at-home tooth whitening. It is not clear, however, if the more concentrated gels will whitening teeth to a greater extent, as no controlled clinical trials have been reported. The authors conducted a double-blind study of human subjects to evaluate whether a 15 percent CP tooth-whitening system was more effective than a 10 percent CP system, and to determine if tooth sensitivity increased with use of the higher concentration.
The authors recruited 57 subjects with maxillary anterior teeth of shade A3 or darker (as gauged against a value-oriented shade guide). The subjects were 18 to 65 years of age and in good general and dental health. After matching the subjects by sex and age, the authors randomly assigned them to either a control group, which used a 10 percent CP whitening agent, or an experimental group, which used a 15 percent CP agent.
The results indicated that there was no significant difference in shade change between the groups after one week of treatment (t = 1.455, P = .05), but there was a significant difference at the end of the treatment period (t = 2.303, P < .05), as well as two weeks after treatment concluded (t = 2.248, P < .05). There was no significant difference in sensitivity (t = 1.399, P > .05).
There was a significant difference in color change between the 10 percent CP and 15 percent CP groups at the end of the study period. There was no significant difference in level of tooth sensitivity between the two groups, and the incidence was equal; there was, however, a significant difference in variability of tooth sensitivity between the two groups.
If performed under the careful guidance of a dentist, at-home whitening is an effective treatment, regardless of whether 10 percent CP or 15 percent CP is used. There may be added color change and varying sensitivity with the use of 15 percent CP.
不同浓度的过氧化脲（CP）制剂被广泛用于家庭牙齿美白。然而，由于尚无对照临床试验报道，目前尚不清楚浓度更高的凝胶是否能使牙齿美白效果更显著。作者对人体受试者进行了一项双盲研究，以评估15%CP牙齿美白系统是否比10%CP系统更有效，并确定使用更高浓度时牙齿敏感度是否会增加。
作者招募了57名上颌前牙颜色为A3或更深（根据以数值为导向的比色板判断）的受试者。受试者年龄在18至65岁之间，全身及口腔健康状况良好。在按性别和年龄匹配受试者后，作者将他们随机分为对照组（使用10%CP美白剂）或实验组（使用15%CP制剂）。
结果表明治疗一周后两组之间的颜色变化无显著差异（t = 1.455，P = 0.05），但在治疗期结束时存在显著差异（t = 2.303，P < 0.05），治疗结束两周后也存在显著差异（t = 2.248，P < 0.05）。敏感度方面无显著差异（t = 1.399，P > 0.05）。
在研究期结束时，10%CP组和15%CP组之间的颜色变化存在显著差异。两组之间牙齿敏感度水平无显著差异，发生率相同；然而，两组之间牙齿敏感度的变异性存在显著差异。
如果在牙医的仔细指导下进行，家庭美白是一种有效的治疗方法，无论使用10%CP还是15%CP。使用15%CP可能会增加颜色变化并导致不同程度的敏感度变化。
