Do whitening toothpastes actually work? – Linda Greenwall
Aesthetic Dentistry Today editor-in-chief, Linda Greenwall BEM, examines claims made by so-called whitening toothpastes
Reports in the media have discussed a recent ruling from the Advertising Standards Authority (ASA) stating that some adverts for whitening toothpastes are misleading, resulting in these adverts being banned.
Claims made for Sensodyne True White toothpaste cannot be believed, the Advertising Standards Authority (ASA) said. GSK, the manufacturer of Sensodyne, said that by using its True White toothpaste you could ‘have sensitive tooth care and whiter teeth’. However, rival toothpaste giant, Colgate Palmolive, complained the claims were false, and that Sensodyne True White did not give better whitening than a standard toothpaste.
In response, GSK supplied studies to support its claims. However, the ASA dismissed these studies, stating: ‘No evidence was provided to show this toothpaste was more effective at whitening than other Sensodyne toothpastes that were not marketed as whitening toothpastes.’ The watchdog said adverts were therefore misleading and the claims should not be made again.
In September 2017, the ASA received three complaints about whitening claims made about Colgate’s Max White 360 toothbrush and whitening pen. Colgate responded that the toothpaste contained hydrogen peroxide to remove stains embedded in the teeth, as well as an abrasive to remove surface stains and a phosphate salt to help prevent and loosen stains. After investigation and further information from Colgate, the ASA reported these claims were not misleading.
Extrinsic stain removal
So what are the facts about whitening toothpastes? Firstly, one needs to understand the different factors that cause staining and discolouration on teeth.
Extrinsic staining are stains that occurs on the external surface of teeth, often near the gingival margin. It can be removed by brushing teeth effectively at the gingival margin to remove the yellow plaque. The removal of this yellow plaque is often misleadingly called whitening of the teeth. The teeth appear cleaner as the yellow plaque is removed; some manufacturers claim this as tooth whitening.
This is not intrinsically whitening the tooth but removal of extrinsic yellow surface plaque. If the plaque is not sufficiently removed, it can become calcified and will need to be professionally removed. Tea, coffee, and other drinks can stain the extrinsic plaque by adhering to the plaque.
Cleaning teeth thoroughly and effectively by brushing teeth with a toothpaste – any toothpaste – will remove the yellow plaque, giving the appearance that the tooth is whiter. In reality, the tooth is not actually whiter, but it is cleaner. The instrinsic colour of the tooth has not been whitened.
Thus, when a whitening toothpaste claims a whitening effect, it may not actually be whitening the tooth but assisting in cleaning the yellow plaque off the tooth, giving the appearance that the actual tooth is whiter.
Most toothpaste manufacturers trademark their whitening ingredients and it is a trade secret how their toothpaste effectively whitens the teeth. If the toothpaste does not actually contain hydrogen peroxide, or it contains carbamide peroxide at a level below 0.1% hydrogen peroxide it cannot intrinsically help to whiten the tooth. Other ingredients are typically fruit enzymes such as citrain and papain, which reduce the staining on the tooth.
Desensitising toothpastes are a different matter. Many of the toothpastes used when a patient is undertaking tooth whitening treatment help to soothe the tooth by blocking the dentinal tubules. They normally contain ingredients such as novamin, amorphous calcium phosphate, arginine, and fluoride.
As tooth whitening treatment can result in sensitivity during whitening, up to 85% of patients can experience some type of sensitivity, so desensitising toothpastes are a useful adjunct to helping to desensitise the tooth.
This month we have an excellent series of articles all dealing with improving aesthetics in a minimally invasive way with whitening, bonding and aligning, and other simple treatments.
Linda Greenwall BEM
BDS MSc MGDS RCS MRD RCS FFGDP(UK)
Greenwall LH (2017) Tooth whitening techniques 2nd edition. CRC Press
This article was originally published in the April 2018 issue of Aesthetic Dentistry Today. Read more articles like this in Aesthetic Dentistry Today and gain three hours’ verifiable CPD with every issue. Click here to subscribe or call 01923 851 777. Get in touch via Twitter @AesDenToday or facebook.com/AesDenToday.