“Everyone wants to be browner, weigh a few pounds less and have whiter teeth”. This phrase may be as debatable as you like, but it is undeniable that we all like white teeth. The bad thing is when, for various reasons, the smile does not meet the wearer’s desires. Let’s take a look at these causes and their possible solutions:
Teeth can be stained by various factors: by tobacco tar, by some medication, by some food or by the presence in the mouth of certain types of bacteria that, although not dangerous to health, stain the teeth. These stains can be removed with a simple oral cleaning, a simple, painless and harmless technique. If the cause is not corrected and the stains reappear over time, the cleaning should be repeated.
Chemical teeth whitening
It can also happen that the teeth have a normal color but the smile appears darkened because they are crowded and cast shadows, or because they are small and leave spaces between them. This can be solved by orthodontics to reposition the teeth or by restorative techniques to modify their shape and size.
Another possibility is that the teeth are white, but not as white as one would like. Here the solution may be chemical tooth whitening, in which a gel that releases oxygen, a gas that produces the whitening effect, is applied to the teeth. In order for the oxygen to be released, the gel must be heated, and this can be done in two ways:
1. At high temperature: about 60° Celsius, which is applied in the clinic by means of a special lamp. The session lasts about an hour, and is usually repeated once or twice. The disadvantages are that the whitening effect diminishes in the following months and during the treatment the teeth experience a discomfort that, in sensitive people, can become very painful. Even so, this discomfort disappears spontaneously in twenty-four to forty-eight hours without any residual lesion being observed.
2. At low temperature: 37°C, the body temperature. The gel is placed in a transparent sheath and the sheath is fitted over the teeth and held for one or several hours, depending on the type of gel used. With the cover on, the patient can speak and lead a normal life (except for eating), so the patient applies the treatment at home, daily, for three or four weeks. It requires some persevering collaboration on the part of the patient, but the whitening effect is permanent and the treatment is painless. Only extremely sensitive people may notice some discomfort, generally tolerable. It is not uncommon to combine the two treatments, first the one done in the clinic and then the one done at home.
The downside of chemical whitening is that its effect depends on the type of tooth. Some patients obtain very evident results and others more modest ones. Strictly speaking, they are only useful to achieve a few more degrees of whiteness in teeth of normal color.
Tooth coating
When the color of the teeth is very dark (staining due to antibiotics, devitalized or traumatized teeth, elderly people…) or when the color to be obtained is spectacularly white, that is to say, when the difference between the color from which it starts and the color to be obtained is great, chemical whitening is inoperative. In these cases it is necessary to cover the tooth with a white material that hides the unwanted color. This can also be done in two ways:
1. by grinding the tooth: Dental caps (also called crowns) completely cover the tooth, and the tooth has to be ground down to the shape of a stump, over which the cap fits. Dental veneers or facets only cover the visible side of the tooth, the front side, so the grinding is limited to this side. The dentist carves the teeth, takes a measurement of the mouth and sends it to the laboratory; there the piece is made and sent back to the dentist, who cements it in place. They are usually made of porcelain. This material cannot be retouched in the mouth, so once placed, any modification or repair of a defect has no other solution than to remove the restoration and replace it with a new one. On the other hand, carving is an irreversible mutilation. The tooth is ground for life since, unlike other tissues, it is not capable of regenerating.
2. Without grinding the tooth: This technique is based on materials known as composites, which come in paste form and are placed, adhered and modeled directly on the tooth, setting them with a special light. There is no need to wear down the teeth, the procedure is painless and usually does not require anesthesia. It is usually completed in a single session that can last up to three or four hours, including some breaks, if several teeth are to be treated. The main advantage of this technique is its harmlessness: the tooth does not suffer any aggression and at any time everything done could be removed and leave the teeth as they were before starting the treatment. Composites can also be retouched directly in the mouth, so that modifications or repairs in case of deterioration are usually simple and do not require the entire restoration to be redone.
These two techniques have the added advantage that in addition to changing the color, they allow the shape, size and, within certain limits, the position of the teeth to be modified.