Everything you need to know about teeth whitening from an actual dentist

Teeth whitening is one of the most sought after aesthetic procedures in dentistry. Every day new promises of miraculous products appear on the market, causing many people who venture into this universe of “quick and cheap solutions” suffer the consequences of their choices later.

First of all, it’s important to understand that dental discoloration can happen through the natural process of dental aging, because of extrinsic (external) factors such as food or drinks with artificial coloring, cigarettes, some mouthwashes, amalgam dental fillings, or intrinsic (internal) factors such as post-trauma hemorrhages, dental cement, systemic changes, tetracycline pigmentation, among others.

How does teeth whitening work?

The whitening process performed or accompanied by a professional consists of applying a hydrogen peroxide or carbamide based gel to the dental surface. In short, these gels act in the following way: they penetrate the dental structure, break apart the pigment that darkens the dental structure into smaller and lighter carbon chains, then transforms into carbon dioxide and water and is released from the dental structure with oxygen. In other words, the gel deep cleans the teeth, which guarantees a visible, satisfactory and lasting result when combined with the cooperation of the patient.

Cautions and contraindications:

Each patient is unique, therefore before anything is applied to your teeth it is fundamental that some factors be properly analyzed to reduce risks. It’s necessary to check for cavities, cracks, exposed dentin, gingival retraction and any other factor that exaggerates the dental structure, leading to sensitivity during and after treatment. The presence of fillings must also be analyzed, especially the back ones as in most cases they need to be replaced. Other contraindications include those with gingivitis, periodontal disease, extensive restorations, who smoke, children under 13, pregnant women, lactating women, or anyone allergic to the products used.

Teeth whitening at home vs. in the dental office

Teeth whitening can be performed by the dentist (in a dental office) or by the patient at home with the dentist’s supervision and orientation.

The advantage of whitening done in a dental office is the professional’s supervision during the procedure, the use of gingival barriers preventing gels from overflowing and damaging the gums, in addition to greater control of the application in regions with gingival retraction. However, more visits to the office are necessary, which makes it a more expensive procedure and, in some cases, the recurrence of stains in the short term may be greater. However, the results are achieved faster as the product concentration is higher. In the option where the patient takes the product home, gel concentrations are lower, and in order for the expected result to be achieved, the patient needs to commit to making the applications correctly using the personalized trays during the time stipulated by the dentist.

You can also choose to combine the two techniques, having a session in the office and continuing at home.

Will teeth whitening increase my teeth’s sensitivity?

Yes. Studies show that about 70% of patients who undergo this procedure report sensitivity during and/or after treatment. However, most whitening gels already contain desensitizing substances such as fluoride and potassium nitrate, though this doesn’t solve the problem in every case. In some cases, the topical use of fluoride, desensitizers, and even oral medications can be used as an aid in preventing or treating sensitivity.

Changes caused by bleaching agents:

When done carelessly, teeth whitening has a negative effect on the enamel and over time can cause irreversible changes to the dental structure, which can result in erosion.

Whitening gels do cause demineralization, however, this superficial mineral loss can be reversed simply by the buffering power of your saliva. That’s right, our saliva has what we call the “fill-in effect” which is nothing more than the ability to maintain a balanced pH, and this salivary balance positively interferes with the remineralization process. Therefore, the slight sensitivity caused by demineralization by whitening gels tends to decrease in a few days.

What about laser teeth whitening?

It has been noted that light sources accelerate the peroxide decomposition process, which decreases treatment time a little, however, with or without light, the whitening process is the same. In other words, many times the use of lasers is more of a marketing ploy than anything else. In addition, many studies have questioned the use of light as part of the tooth whitening process due to the heat generated that could cause injuries to the pulp. However, recent studies have shown that these techniques associated with light sources are considered safe when correctly indicated and performed. It is worth remembering that when it comes to “LASER THERAPY” associated with whitening, the results are extremely more satisfactory as there is less inflammatory reaction and, consequently, less sensitivity.

Do whitening strips work?

Yes. Flexible tapes already contain hydrogen peroxide-based whitening gels, usually at a concentration of 5% to 10%. These tapes can be purchased and applied by the patient without professional monitoring, and therein lies the danger, because, despite whitening the teeth, there is no way to predict the side effects of this type of procedure, nor its duration and effectiveness.

A fellow dentistry professional and colleague bought and tried whitening strips and posted a review on her blog. She reported gum lesions because, as the tapes move, they ended up attacking the mucosa, causing small ulcers and leading to the suspension of treatment.

Preliminary protocol and monitoring are essential in any treatment, and the easy access to this type of treatment makes it difficult for a professional to control and monitor it.

Whitening toothpaste, charcoal, baking soda and the like:

Most whitening toothpastes contain some form of abrasive agents (or charcoal or baking soda…) and/or peroxides in low concentration. Studies show that brushing with abrasive substances tends to increase the enamel and dentin roughness, which can lead to a greater accumulation of plaque. After some time of use, these products cause micro-wear leading to dentinal abrasion. In other words, these toothpastes don’t actually whiten your teeth, but perform somewhat of a superficial polishing (extrinsic stains) and can cause detrimental side-effects since most people use them indiscriminately trying to achieve the desired results. As for the peroxides, in spite of being excellent bleaching agents, they do not result in any significant changes, as they are used in very low concentrations.

The process of changing “teeth color” is much more complex and requires an deep intrinsic cleaning, as mentioned above. Plus, each tooth has a maximum whitening limit to how white it will get. One person’s limit may not be the same as yours. The objective then is to obtain the most harmonious and natural result possible.

To whiten or not?

We have covered many problems associated with teeth whitening, but, to be clear, we are talking about people who make IRRATIONAL use of these procedures, WITHOUT SUPERVISION, and who often try to cram the treatment into SHORT TIME SPAN.

Don’t try to perform teeth whitening on your own and don’t try everything you see on the shelves, and definitely don’t try every product you see on influencers’ profiles, as most have either already undergone professional teeth whitening services or use dental caps.

For quality and safe treatment, look for a trustworthy professional and whiten your teeth without fear.

P.S. I myself have had a session and loved the results!


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