Possible Side Effects

Tissue irritation and tooth sensitivity are both potential side effects of tooth whitening. Tissue irritation can be caused by a poorly fitting tray impinging on the gingival margin, and if trays are being used these should be checked carefully prior to delivering them to patients. The use of high-concentration in-office whiteners requires the use of a liquid dam or other type of dam to prevent the whitener from contacting the soft tissues; it can also result in greater sensitivity than lower concentrations.10 (Figure 9) Failure to apply a dam that completely protects the gingival soft tissues can result in painful chemical burns on the gingivae. If hydrogen peroxide burns do occur, they will appear as little white patches on the gums and heal quickly, but it is important to avoid them in the first place. If they occur and are painful, topical anesthetic agents can be applied, including pain-relieving medicaments typically used for aphthous ulcers.

The second potential side effect to discuss is tooth sensitivity, which may be due to the status of the patient’s dentition or occur as a result of the process of tooth whitening. Prior to undertaking any whitening treatment, it is essential to evaluate the patient for recession, exposed dentin, leaking restorations and cavities. Any of these may be a contraindication for tooth whitening if they cannot be managed either prior to or during treatment depending on the clinical presentation). The second potential side effect to discuss is tooth sensitivity, which may be due to the status of the patient’s dentition or occur as a result of the process of tooth whitening. Prior to undertaking any whitening treatment, it is essential to evaluate the patient for recession, exposed dentin, leaking restorations and cavities. Any of these may be a contraindication for tooth whitening if they cannot be managed either prior to or during treatment (depending on the clinical presentation). If the whitening gel is applied directly to open margins or cavities, it can be extremely painful, and applying whitening gel to any exposed dentin also causes pain and sensitivity. The patient can still be a candidate for whitening treatment, but needs to have the cavities filled or leaking restorations replaced before tooth whitening is performed.

During the tooth whitening procedure, hydrogen peroxide diffuses through the enamel and reaches the inner dentin of the teeth. When in direct contact with exposed dentin, the peroxide breaks down microscopic debris that blocks the openings to the tubules that radiate from the pulp to the surface of the dentin. The fluid within the dentinal tubules moves backward and forward, stimulating the nerve fibers and resulting in tooth sensitivity (pain) in reaction to stimuli such as heat and cold.11 For in-office whitening, the most important steps in the procedure are careful placement of the liquid dam, being certain that the tissue is dry, verify all gingival tissue is covered and that dentin is sealed. It is better to have a little bit of liquid dam overlap on the enamel than to come up short and possibly expose dentin or gingiva.

Tooth sensitivity is a common complaint during tooth whitening that in fact can be well managed.12,13 Much of what makes the difference between a patient’s positive or negative experience with a whitening procedure is the degree to which the patient’s tooth sensitivity can be mitigated. Sensitivity associated with tooth whitening has an acute phase of about one to three days, after which it sharply decreases in degree.14 Making the patient aware of this is a good first step in introducing them to the concept of sensitivity. The reason it is important to do everything possible to prevent sensitivity is that the pain of sensitivity is enough to make people feel extremely distressed. Sensitivity results in sharp, painful impulses in individual teeth. Referring to these sharp impulses as “zingers” is a good way to subtly reassure affected patients that what they are experiencing is not abnormal. Continuing to remind patients that the acute phase of the sensitivity only lasts a couple of days and can be controlled is also important.

Some reasons behind sensitivity could be time of exposure to the whitening agents as well as prolonged exposure to whitening accelerators. Also, some whitening gel formulations may not be efficient enough to help with sensitivity concerns. GloboDent’s In-Office BlanQuest® Pro Teeth Whitening Gel has been designed through both its fast procedures and its formulation, to significantly reduce such risks. The procedure itself is fast with or without the use of a whitening accelerator, allowing for a comfortable and decreasing the risk of sensitivity to occur. Also, it’s gel composition is made with gentle and highly effective ingredients that combined with its PH balance, have been formulated to keep sensitivity risks at a minimum.

Taking precautions to reduce sensitivity is very important. There are many options to reduce and, if necessary, treat sensitivity associated with tooth whitening. Having the patient use a desensitizing toothpaste containing potassium nitrate for two weeks prior to the whitening procedure can reduce sensitivity. Other options include using a whitening agent such as GloboDent’s Remineralizing Gel containing potassium nitrate. In rare cases where sensitivity following tooth whitening does not subside sufficiently, prescription pain relievers can be given or ibuprofen can be recommended. If all precautions are taken against sensitivity, sensitivity risks should be minimized, but because of the potential of post-whitening sensitivity, it is important to always remind patients of this possibility and to contact their dentists for any concerns.

After the potential effectiveness of a tooth whitening treatment has been determined, informed consent has been obtained and sensitivity has been controlled, it is time to proceed with treatment and give the patient his or her instructions. If using a home-use whitener with trays such as the BlanQuest® Home Whitening Kit, the custom trays must be fabricated and the fit checked. It is helpful to perform the first session in the office to help educate patients on the correct use of the trays. If, on the other hand, if the in-office BlanQuest® Pro Teeth Whitening Kit is being used, it is important to first tell the patient to remain still during the procedure in order to avoid dislodging the barrier (liquid dam) placed in the mouth to protect soft tissue from irritation and the burning effects of the peroxide and the whitening lamp. In conjunction with these instructions, the patient should be provided with a means of alerting your attention (such as a bell), as well as a pad of paper and writing instrument so that he or she can let you know about any problems that might come up during the procedure. If hydrogen peroxide irritations do occur, they will appear as little white patches on the gums and the patient should be informed that they will heal quickly. If the patient is experiencing discomfort as a result of this, a topical medication that contains anesthetic can be applied to promote comfort while the burns are healing. The patient should also be instructed to avoid heavily pigmented foods and beverages for 48 hours. Some studies have found that teeth remain extra susceptible to staining pigments in foodstuffs post-whitening for a period of time.18 Informing the patient that he or she can actually make the teeth darker than they were prior to whitening if they ignore these instructions is also important. The primary offenders for tooth stains are coffee, tea, red wine and tobacco. It is also important to inform patients before starting on any tooth whitening procedure that over time the whiteness of the teeth will fade and some degree of color regression will occur.19 This happens with all tooth whiteners. Letting patients know this and also that this can be managed by periodically “touching up” the tooth whitening avoids patient disappointment.

In summary, before implementing a tooth whitening procedure, one must identify whether the patient is a good candidate for whitening, use good informed consent procedures to manage patient expectations, be prepared to answer fundamental questions about the procedure, take preventative measures against and inform patients about the potential for sensitivity, and provide patients with instructions for during and after tooth whitening, including that they need to avoid heavily pigmented foods and beverages post-whitening. Once these preliminary issues are addressed, the actual implementation of the procedure is straightforward, a good marketing tool and a welcome adjunct to other cosmetic treatments.