Myths and facts about teeth whitening

Can I drink coffee, wine, soda, and colored foods during/after teeth whitening treatment?

Studies have indicated that there is no longer a need for dietary restrictions during and/or after whitening treatment, as long as a quality product that follows current protocols and techniques is used, and the treatment is properly conducted by a Dentist. The results of whitening with these foods in the diet were practically the same when compared to white diets.

• Rezende M, Loguercio AD, Reis A, Kossatz S. Clinical effects of exposure to coffee during at-home vital bleaching. Oper Dent. 2013 Nov-Dec;38(6):E229-36. doi: 10.2341/12-188-C. Epub 2013 Apr 9. PMID: 23570297.
• Mori AA, Lima FF, Benetti AR, Terada RS, Fujimaki M, Pascotto RC. Susceptibility to Coffee Staining during Enamel Remineralization Following the In-Office Bleaching Technique: An In Situ Assessment. J Esthet Restor Dent. 2016 Mar;28 Suppl 1:S23-31. doi: 10.1111/jerd.12134. Epub 2015 Jan 30. PMID: 25640880.
• Hass V, Carvalhal ST, Lima SNL, Viteri-Garcia AA, Maia Filho EM, Bandeca MC, Reis A, Loguercio AD, Tavarez RRJ. Effects of Exposure to Cola-Based Soft Drink on Bleaching Effectiveness and Tooth Sensitivity of In-Office Bleaching: A Blind Clinical Trial. Clin Cosmet Investig Dent. 2019 Dec 20;11:383-392. doi: 10.2147/CCIDE.S227059. PMID: 31908538; PMCID: PMC6930015.
• Matis BA, Wang G, Matis JI, Cook NB, Eckert GJ. White diet: is it necessary during tooth whitening? Oper Dent. 2015 May-Jun;40(3):235-40. doi: 10.2341/14-019-LIT. Epub 2015 Mar 6. PMID: 25748208.

Can smokers undergo teeth whitening and achieve good results?

Smokers can indeed undergo teeth whitening and achieve the same results as non-smokers, according to studies. Researchers Dr. Alessandra Reis and Dr. Alessandro Loguercio explain that this habit, however, does interfere with the results over time as it tends to cause teeth to yellow more quickly than in non-smoking patients, but proper prophylaxis and oral hygiene help maintain good results.

• Ness L, Rosekrans Dde L, Welford JF. An epidemiologic study of factors affecting extrinsic staining of teeth in an English population. Community Dent Oral Epidemiol. 1977 Jan;5(1):55-60. doi: 10.1111/j.1600-0528.1977.tb01617.x. PMID: 264419.
• de Geus JL, Fernández E, Kossatz S, Loguercio AD, Reis A. Effects of At-home Bleaching in Smokers: 30-month Follow-up. Oper Dent. 2017 Nov/Dec;42(6):572-580. doi: 10.2341/16-126-C. PMID: 29144876.
• de Geus JL, Rezende M, Margraf LS, Bortoluzzi MC, Fernández E, Loguercio AD, Reis A, Kossatz S. Evaluation of genotoxicity and efficacy of at-home bleaching in smokers: a single-blind controlled clinical trial. Oper Dent. 2015 Mar-Apr;40(2):E47-55. doi: 10.2341/14-121-C. Epub 2014 Dec 23. PMID: 25535783.
• de Geus JL, de Lara MB, Hanzen TA, Fernández E, Loguercio AD, Kossatz S, Reis A. One-year follow-up of at-home bleaching in smokers before and after dental prophylaxis. J Dent. 2015 Nov;43(11):1346-51. doi: 10.1016/j.jdent.2015.08.009. Epub 2015 Aug 21. PMID: 26303401.

Is light necessary for teeth whitening?

Using light during in-office teeth whitening does not improve results or cause a color change, regardless of the concentration of hydrogen peroxide and type of light. Additionally, light increases the risk of sensitivity and pain during the whitening process. Therefore, dentists should use light-activated systems with caution or avoid their use altogether.”Based on current evidence, the use of light is unnecessary and adds to the cost of the procedure, as the clinician needs to acquire equipment for the office. Furthermore, there is no real benefit. For the whitening effect of light to occur on any substrate, many hours are required, which does not happen in a dental setting,” explain the researchers.

• He LB, Shao MY, Tan K, Xu X, Li JY. The effects of light on bleaching and tooth sensitivity during in-office vital bleaching: a systematic review and meta-analysis. J Dent. 2012 Aug;40(8):644-53. doi: 10.1016/j.jdent.2012.04.010. Epub 2012 Apr 21. PMID: 22525016.
• Maran BM, Burey A, de Paris Matos T, Loguercio AD, Reis A. In-office dental bleaching with light vs. without light: A systematic review and meta-analysis. J Dent. 2018 Mar;70:1-13. doi: 10.1016/j.jdent.2017.11.007. Epub 2017 Dec 29. PMID: 29289725.
• Maran BM, Ziegelmann PK, Burey A, de Paris Matos T, Loguercio AD, Reis A. Different light-activation systems associated with dental bleaching: a systematic review and a network meta-analysis. Clin Oral Investig. 2019 Apr;23(4):1499-1512. doi: 10.1007/s00784-019-02835-x. Epub 2019 Feb 14. PMID: 30767069.

Charcoal, turmeric, toothpaste, chewing gum, mouthwashes, and whitening strips: Do they whiten teeth?

Every day, numerous products are marketed claiming to whiten teeth without the need for the supervision of a dentist. However, experts warn that these products are not actual teeth whiteners and do not actually whiten teeth. Some of them may only assist in maintaining results achieved after teeth whitening by contributing to dental hygiene and prophylaxis. Clinically speaking, these products do not penetrate the dental structure due to insufficient concentrations of active agents. Additionally, products like charcoal are dental abrasives, not teeth whiteners, and according to studies, they can be harmful to dental structure.

• Jiang N, Zhang C, Agingu C, Attin T, Cheng H, Yu H. Comparison of Whitening Dentifrices on the Effectiveness of In-office Tooth Bleaching: A Double-blind Randomized Controlled Clinical Trial. Oper Dent. 2019 Mar/Apr;44(2):138-145. doi: 10.2341/17-333-C. Epub 2018 Aug 14. PMID: 30106335.
• Brooks JK, Bashirelahi N, Reynolds MA. Charcoal and charcoal-based dentifrices: A literature review. J Am Dent Assoc. 2017 Sep;148(9):661-670. doi: 10.1016/j.adaj.2017.05.001. Epub 2017 Jun 7. PMID: 28599961.
• Franco MC, Uehara J, Meroni BM, Zuttion GS, Cenci MS. The Effect of a Charcoal-based Powder for Enamel Dental Bleaching. Oper Dent. 2020 Nov 1;45(6):618-623. doi: 10.2341/19-122-L. PMID: 32243248.

In-office whitening is not as effective as at-home whitening?

Current high-quality products, even with a high concentration of hydrogen peroxide, are more alkaline and maintain a stable pH, especially those that do not require gel replacement. They are capable of achieving effective results. This characteristic also minimizes enamel demineralization, resulting in less sensitivity and greater longevity of whitening.According to Dra. Alessandra Reis and Dr. Alessandro Loguercio, if the applied technique adheres to the recommended protocol, with at least two clinical sessions, occasionally three, the result achieved through in-office whitening is as stable and effective as the outcome of at-home whitening.

Study Long-term efficacy of in-office and at-home bleaching: a 2-year double-blind randomized clinical trial, mentioned by Dr. Alessandro Loguercio.

• Pinto A, Bridi EC, Amaral F, França F, Turssi CP, Pérez CA, Martinez EF, Flório FM, Basting RT. Enamel Mineral Content Changes After Bleaching With High and Low Hydrogen Peroxide Concentrations: Colorimetric Spectrophotometry and Total Reflection X-ray Fluorescence Analyses. Oper Dent. 2017 May/Jun;42(3):308-318. doi: 10.2341/16-032-L. PMID: 28467252.
• Torres CR, Crastechini E, Feitosa FA, Pucci CR, Borges AB. Influence of pH on the effectiveness of hydrogen peroxide whitening. Oper Dent. 2014 Nov-Dec;39(6):E261-8. doi: 10.2341/13-214-L. Epub 2014 Aug 19. PMID: 25136903.
• Mena-Serrano AP, Parreiras SO, do Nascimento EM, Borges CP, Berger SB, Loguercio AD, Reis A. Effects of the concentration and composition of in-office bleaching gels on hydrogen peroxide penetration into the pulp chamber. Oper Dent. 2015 Mar-Apr;40(2):E76-82. doi: 10.2341/13-352-L. Epub 2014 Dec 23. PMID: 25535786.
• Tay LY, Kose C, Herrera DR, Reis A, Loguercio AD. Long-term efficacy of in-office and at-home bleaching: a 2-year double-blind randomized clinical trial. OAm J Dent. 2012 Aug;25(4):199-204. PMID: 23082382.

Is at-home whitening with carbamide peroxide more effective when used all night?

Studies testing different application times of carbamide peroxide and its clinical effectiveness have shown that using it for 1 to 8 hours yields similar results, confirming that there is no need for overnight application. After 4 hours, the teeth whitener contains less than 30% active carbamide peroxide, which does not significantly contribute to the whitening process. Chart illustrating the use of 10% carbamide peroxide over different time periods in 16 days, compared to patient satisfaction.

• Cardoso PC, DDS, MS, PhD; Reis A, DDS, PhD; Loguercio AD, DDS, MS, PhD; Vieira LCC, DDS, MS, PhD; Baratieri LN, DDS, MS, PhS. Clinical effectiveness and tooth sensitivity associated with different bleaching times for a 10 percent carbamide peroxide gel. Am J Dent. 2010 Oct;141(10):1213-20. PMID: 20884923

Is it necessary to cover the entire tooth surface with the whitening gel for effective teeth whitening?

Many professionals have possibly been advised to apply more whitening gel to the canines or more precisely to the cervical region of the tooth, as there was a belief that these teeth were the most difficult to whiten. However, this belief was not proven true after studies showed results in cases of in-office whitening during orthodontic treatment. Upon removal of the brackets, it was observed that the previously covered surface was whitened in the same way. Furthermore, to confirm the insignificance of applying gel to the entire tooth surface, cases were conducted protecting the cervical region, and surprising results were achieved, confirming that the whitening effect truly occurs from the inside out and opening up the possibility of performing the aesthetic procedure also on the palatal side.

• Jadad E, Montoya J, Arana G, Gordillo LAA, Palo RM, Loguercio AD. Spectrophotometric evaluation of color alterations with a new dental bleaching product in patients wearing orthodontic appliances. Am J Orthod Dentofacial Orthop. 2011 Jul;140(1):e43-7. PMID: 21724070
• Gomes MN, Dutra H, Morais A, Sgura R, Devito-Moraes AG. In-office bleaching during orthodontic treatment. J Esthet Restor Dent. 2017 Apr;29(2):83-92. PMID: 27792268
• de Sá JL, Silva JS, Herkrath FJ, Favoreto MW, Reis A, Silva LM, Loguercio AD, Martins LM. In-office bleaching with complete cervical third protection protocol: a split-mouth, double-blind, randomized clinical trial. Am J Dent. 2021 Oct;34(5):281-285. PMID: 34689453
• Silva LM, da Costa Lacerda ÍA, dos Santos DB, Herkrath FJ, da Silva KL, Loguercio AD, de Moura Martins L. In the at-home bleaching treatment applied only on the lingual surface as effective as that on the buccal surface? A randomized clinical trial. Clin Oral Investig. 2021 Aug 19. doi: 10.1007/s00784-021-04128-8. PMID: 34410498

Do more concentrated gels provide faster and more stable teeth whitening?

Gels with higher or lower concentrations show the same effectiveness and whitening stability. On the other hand, more concentrated gels may provide slightly quicker results in the first week of treatment, but the risk and intensity of sensitivity may be higher when using these gels. It is advisable for the professional to align the patient’s expectations and desires to identify together which gel and procedure (at-home or in-office) would result in a satisfactory outcome.

• de Geus JL, Wambier LM, Boing TF, Loguercio AD, Reis A. At-home bleaching with 10% vs more concentrated carbamide proxide gels: a systematic review and meta-analysis. Oper Dent. Jul/Aug 2018;43(4):E210-E222. PMID: 29949477

In conclusion, the importance of science in the pursuit of evidence to prove the necessity and effectiveness of clinical practices is indisputable. According to experts, scientific research is essential in any procedure performed on humans; after all, patient health and safety should always come first. Furthermore, seeking to understand and demystify topics like the ones covered in this article can simplify procedures and even reduce costs in treatments. Want to learn more? Watch the full lecture with Prof. Dr. Alessandro Loguercio and Prof. Dr. Alessandra Reis on the “Papo de Consultório” segment hosted by FGM: