An Overview of Extrinsic Tooth Bleaching and its Impact on Oral Restorative Materials

Aim: The aim was focused on compiling a comprehensive overview of the extrinsic tooth bleaching and its mechanisms including in vitro and in vivo measurement methods and analyzing factors affecting the efficacy of the bleaching process on restorative materials and tooth structures. Background: The importance of tooth bleaching for patients has notably gained importance and been accompanied by a dramatic increase in the number of relevant products and procedures over the past two decades, with a concomitant rise in publications on this topic. Literatures have put forth that the mechanisms of tooth bleaching by peroxide agents occur by the diffusion of peroxide through the enamel to cause oxidation, and hence, lightening of colored species, particularly, within the dentinal regions. Results: An electronic search was conducted across Ovid Medline, complemented by a manual search across individual databases, such as Cochrane, Web of Science databases, and Google Scholar for the purpose of literature analysis on the mentioned topic. The studies were reviewed and compared. This article summarizes the current scientific and clinical opinions through a brief review with regards to the preferred way of bleaching and its impact on restorative materials. There are controversies in terms of performing tooth bleaching. Regarding extrinsic tooth bleaching, certain literature have pointed out that the in-office method is being followed by a high number of dental practitioners, whereas it should be practiced based on selection of the right cases. Conclusion: Based on previous findings, it is concluded that at-home bleaching technique appears to be the safest technique currently available, which is rapid, easy, and cheap. However, the correct selection of the cases is mandatory. The in-office method provides good outcomes, while it may be insufficient for correcting extreme discoloration. It should be considered that time and concentration are two crucial parameters that have a great influence on the successful bleaching process. These techniques are not entirely free from hazards, and therefore, using these agents under appropriate supervision and consultation with dental professionals is highly essential. Clinical significance: In-office tooth bleaching is a great method for providing rapid tooth bleaching, while it is not as REVIEw aRtIclE 1Central Research Center, School of Stomatology, China Medical University, Shenyang, Liaoning Province, PR China 2-4Department of Orthodontics, School of Stomatology, China Medical University, Shenyang, Liaoning Province, PR China Corresponding Author: Yi Liu, Department of Orthodontics School of Stomatology, China Medical University, Nanjing North Street 117#, He-Ping, District Shenyang 110002, PR, China Phone: +862431973999, e-mail: liuyi@cmu.edu. cn 10.5005/jp-journals-10015-1494 safe as the home bleaching method. With the presented data over the past two decades, at-home bleaching has also become an accepted and integrated procedure. However, long-term health risks are also associated with professional at-home tooth bleaching using 10% carbamide peroxide (CP) gels, which is equivalent to 3.5% H2O2. Hence, it is recommended that the latter method should be mindfully approached when preferring long-term bleaching processes.