Teeth whitening: ensure a whiter smile

Most people want to show off a beautiful smile with healthy, white teeth. For this, hygiene habits, such as brushing your teeth always after meals and flossing, are essential.

However, it is a fact that maintaining the whiteness of teeth is not always easy. Over time, they even tend to darken and become stained naturally.

William Frossard, dentist specializing in Aesthetic Dentistry, PhD in Periodontics, Master in Dentistry, specialist in Dental Prosthesis and professor and coordinator of the Specialization Course in Clinical Dental Prosthesis (UERJ), comments that teeth darken due to several factors. “As a biotype, for example. Some people have yellower teeth and others whiter teeth – a fact that would be linked to the genetic factor”, he says.

“Medicines like tetracycline – an antibiotic that was widely used in the past – tend to stain teeth, especially when used in childhood. Trauma, for example, teeth that suffered some type of trauma and had bleeding inside them, tend to get darker over time”, adds the specialist.

In addition: “cavities, age, habits such as smoking, ingestion of highly pigmented foods and drinks, such as wine, chocolate, excess soft drinks, accelerate the natural process of darkening of the teeth”, adds Frossard.

It is not by chance that dentists’ offices receive more and more patients in search of a white and impeccable smile. “Tooth whitening is indicated when the patient has darkened or yellowed teeth. The minimum age is usually 16 years old (the age at which the patient has all dental apices closed). The older the patient, the less effective the technique will be”, explains the specialist.

Frossard points out that the patient does not have to wait for the teeth to be stained or too dark to opt for a whitening treatment. “From the moment the patient feels uncomfortable with the color of his smile, it’s time to whiten”.

Types of professional teeth whitening

There are external whitening and internal whitening. Below you know the differences between them:

internal whitening

Tatiane J. Machado Buscarilli, a dentist at Sorridents, explains that internal tooth whitening consists of the application of a whitening gel inside the coronal portion of the tooth. “An opening is made behind the tooth, where the whitening material is deposited. This technique is indicated for endodontically treated teeth, teeth darkened by metallic reaction and trauma cases,” she says.

The dentist adds that this gel must be changed weekly until the expected result is achieved, respecting the maximum period of two months.

Juliana Rossi, a dentist specializing in aesthetic dentistry, points out that the bleach used can be based on hydrogen peroxide, carbamide peroxide or sodium perborate. “The technique is the ‘walking bleach’, where the product is placed and it stays inside the tooth and the patient comes back after a week or five days, and together with the dentist they assess whether it is necessary to change the product and redo it”, adds.

“One characteristic of this technique is that it is unpredictable: it is not possible to be sure that the tooth will be the same color as the other teeth”, emphasizes Juliana.

The cost of the technique, according to Juliana, ranges from R$700 to R$1,500 per tooth.

external whitening

External whitening, as explained by Juliana, is a technique where the whitening gel is placed on the “outside” of the tooth. “By a chemical reaction process, the gel releases oxygen, a free radical, which passes through the enamel layer (outside layer of the tooth) and will break the pigment chain into small molecules (carbon dioxide and water) and eliminate them. them by diffusion. This effect is cumulative, that is, the tooth whitens with each new contact with whitening agent”, she says.

External whitening can be subdivided today into three techniques:

1. Office whitening

Valéria Baraldi, dentist, explains that this type of whitening is done in a dental office, where the dental surgeon applies a protective gingival barrier and a gel on the teeth. “This gel stays in contact with the teeth for around an hour; then it can be removed. We usually get good results with two or three sessions,” she says.

According to Juliana, the average amount charged for this type of whitening ranges from R$1,000 to R$2,500. “And the time to be redone varies according to the patient’s diet and oral hygiene. But, on average, people are satisfied for a year and a half to two years, where they decide together with us to do a ‘touch up’ on the whitening – which can be fixed in a week”, she says.

2. Home whitening

Frossard explains that at-home whitening consists of the use of a silicone tray in which the patient himself puts the whitening gel, in a lower concentration, and fits it in the mouth. “We typically recommend that this patient wears it overnight while sleeping. This type of whitening lasts around three weeks, which can be extended to more or less depending on the dental response and the intensity of color that the patient wants”, he says.

“When we do at-home bleaching, we usually use carbamide peroxide or hydrogen peroxide with different percentages for each case”, highlights the specialist.

Juliana comments that this is one of the oldest techniques, with very satisfactory results and with a report of low sensitivity. “It is very well indicated for the vast majority of patients. More and more gels are adapted to the patient’s life so that they are easier for daily use. We have gels that stay in contact with the tooth for four hours, but they can stay for eight hours, so the patient can sleep with the plate on. For those who do not adapt to this permanence, we have gels that can stay for 20 to 30 minutes,” she explains.

According to Juliana, the average amount charged ranges from R$1,000 to R$1,500. “The time to be redone depends on the patient’s diet and oral hygiene, but on average people are satisfied for a year and a half to two years, when they decide together with us to do a ‘touch up’ on the whitening”.

3. Laser whitening

This method, according to Valéria, is very similar to in-office bleaching, “however, the clarifying gel is activated with laser, which increases the permeability of the gel in the spaces between the enamel prisms, making the whitening more intense”.

Tatiane points out that in just two or three sessions the whitening is ready. “The dentist applies a gel (with a much higher concentration of the product than homemade gel) and it is activated with the laser light. Due to this gel + laser association, and because it has a higher concentration, we see a more satisfactory result than homemade”, she says.

The average amount charged, according to Juliana, ranges from R$1,500 to R$2,500. And the time to be redone also varies according to the patient’s habits, but, in general, people are satisfied for a year and a half to two years until they need to do a “touch up”.

It is worth noting that it is also possible to associate two types of whitening, such as the one done in the office with the homemade one, to intensify the results. “You can do, for example, one or two in-office sessions and, in between, home whitening. The duration of whitening will depend on the expected result, but on average it takes four weeks”, comments Juliana.

Regarding the values ​​of the treatments in general, Frossard highlights that they vary according to the degree of difficulty and time. “But we can cite a variable that goes from R$1,000 to R$3,000”, he adds.

Is it possible to whiten teeth at home?

Many people would like to be able to whiten their teeth at home, without having to opt for a professional technique. But is this possible and recommended? Are there risks, for example, in using baking soda on your teeth? And hydrogen peroxide? Can some toothpastes and mouthwashes work as whiteners? Are whitening adhesive strips really effective? These are the main doubts on the subject and that, below, the professionals clarify.

Sodium bicarbonate

Valeria explains that some people use baking soda as a toothpaste to whiten their teeth. “However, it does not promote the same whitening as what is done in the office, the bicarbonate only removes the surface stains of the enamel”, he says. In addition, there are risks in using this type of product. “If the person uses it too often, there may be a wear of the enamel, which may cause dentin sensitivity”, he adds.

Hydrogen peroxide

Juliana points out that it is not recommended to use hydrogen peroxide to whiten teeth. “This substance can significantly change the pH of the mouth, causing lesions and aggravating possible existing problems, such as gingivitis and sensitivity. In addition, use without proper balance can result in stained and even more uncomfortable-looking teeth than simple yellowing.”

“This type of substance can be recommended in some cases for patients with problems such as periodontal disease, severe gum inflammation, where there are anaerobic bacteria and the oxygen contained in the product ends up ‘killing’ these bacteria and helping the disease, but this should always be recommended by a professional”, explains Juliana.

Toothpastes and mouthwashes

Juliana remembers that toothpastes are used during brushing and “the whitening gel has time as an important factor for whitening, just because of that you can see that these toothpastes will not stay long enough for there to actually be a whitening in the tooth” .

“What usually happens is that companies make a toothpaste a little more abrasive, and then it is like an ‘exfoliation’ on the ‘outside’ of the tooth, removing extrinsic stains, those famously caused by dietary dyes (such as coffee, wine, etc.). In addition, because a compound called triclosan is inserted, it has the potential to inhibit supragingival plaque,” ​​says Juliana.

“But it is important to point out that today the patient wears out the tooth enamel more due to brushing with excessive force and, therefore, it is very important to prevent these more abrasive toothpastes from worsening these wears even more”, says Juliana.

“Continuing in the same line of reasoning, mouthwashes also do not have an effective result in terms of teeth whitening because they also spend a very short time in the mouth. And even if they have a whitening substance, the concentration has to be very low so as not to harm the gingival tissues”, highlights the dentist Juliana.

whitening strips

Juliana explains that whitening strips are normally impregnated with hydrogen peroxide. “They are made with active whitening principles, however, they are made universally, that is, they are not customized for each patient. Therefore, its fixation in the mouth can be impaired and, therefore, the whitening effect may be unsatisfactory, as other types of whitening are fully customized, ensuring…