Major clinical approaches to tooth whitening techniques and differences in terms of sensitivity and protection: a systematic review
Authors: Zanelatto Drica Garcia , Moreira Janaina Cardoso 
Published: March 2024

Introduction: Tooth whitening is an initial step in the analysis and reproduction of the aesthetics of the smile, so the dentist must know how to diagnose the causes of color changes, and recommend whitening before proposing the appropriate dental procedure. With technological advances, tooth whitening techniques have emerged to facilitate their use improve comfort and safety, and reduce time spent performing the technique. The conventional means of external tooth whitening is with carbamide peroxides or light-activated hydrogen or not. However, both at-home and in-office whitening procedures cause tooth sensitivity. There is a new whitening proposal on the market without the use of whitening gels, thus reducing post-treatment sensitivity. This proposal highlights ultraviolet light as a whitening agent. Objective: It was to carry out a concise systematic review of the main clinical approaches to tooth whitening techniques, to point out the differences between them in terms of sensitivity and tooth protection. Methods: The PRISMA Platform systematic review rules were followed. The search was carried out from January to February 2024 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 178 articles were found, 40 articles were evaluated in full and 20 were included and developed in the present systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 21 studies with a high risk of bias and 31 studies that did not meet GRADE and AMSTAR-2. Most studies did not show homogeneity in their results, with X2=67.4%>50%. It was concluded that tooth whitening can be indicated in practically all situations in which tooth darkening occurs, such as pulp tissue decomposition, internal hemorrhage, trauma, use of medications, restorative materials, and systemic conditions such as fluorosis, jaundice, and fetal erythroblastosis, among others. others. Contraindications for tooth whitening treatment occur in children under 10 years of age. Whitening using the home technique uses products with lower concentrations, between 10% and 22% carbamide peroxide. In-office, 16% carbamide peroxide was effective. In office-based tooth whitening, higher concentrations of whitening substances are used and laser, LED, ultraviolet, and halogen light can be used to intensify the whitening process. Patients undergoing vital teeth whitening report sensitivity or discomfort during treatment. Oxidative stress generated by bleaching agents can cause apoptosis and damage to periodontium DNA (genotoxicity) and cellular cytotoxicity. A new generation of whitening agents with low concentrations of hydrogen peroxide (3.5% and 15%) was introduced on the market for in-office teeth whitening, aiming to achieve greater safety and efficiency in tooth whitening.