What causes discolouration of the teeth?
External discolouration of the teeth stems from deposits of the surface of tooth enamel. Many substances have the potential to aggravate this situation, such as dental plaque, tartar, coffee, soft drinks, wine, tobacco and fruit juice. On the other hand, internal discolouration of the teeth manifests itself within tooth enamel or dentine. The main cause is aging, but medication (antibiotics, for one), fluoride and certain types of trauma can also come into play.
What process is used to whiten teeth?
Whitening is a process used to lighten the colour of the teeth and to help them reflect light more effectively. Tooth enamel can be compared to a sponge, which, with the passage of time, a patient’s lifestyle and eating/drinking habits, absorbs stains that gradually darken teeth. Whitening is like thoroughly cleaning the pores of tooth enamel. However, the act of bleaching teeth alone cannot correct all issues. Cosmetic treatments, such as dental crowns and porcelain veneers, may be better suited to the expectations of some patients.
The active ingredient can be carbamide peroxide or hydrogen peroxide, both of which have proven track records in terms of their aesthetic properties. In contact with teeth, the active ingredient releases oxygen, which eliminates deep stains and in that way lightens the colour of teeth. Seeing as enamel remains unaltered, whitening is a very safe, simple and effective procedure.
Does the active ingredient’s concentration affect the result?
A higher concentration of peroxide yields quicker results, but its downside is that it increases dental sensitivity. A lesser concentration procures the same results once the treatment is complete, without increasing sensitivity. We thus recommend the use of a lesser concentration in peroxide, especially in patients who already experience dental sensitivity.
How many hours does the product have to remain applied on teeth?
When applied as a gel, peroxide’s efficacy is surprising. It quickly breaks down during the first hours following its application, conserving, however, 50% of its efficacy after two hours, and 35% after four hours of wear. Its efficacy continues to decrease with the passage of time and is lost approximately eight hours after it was first applied.
In the case of home bleaching products, dentists usually suggest wearing the mouthpiece for thirty minutes to two hours each day. However, wearing it for longer periods of time to obtain better results is not contraindicated. If the patient has sensitive teeth, reducing mouthpiece wearing time may solve the issue. In cases of significant discolouration, we suggest that the patient wear the mouthpiece overnight for maximum efficacy.
Who can benefit from a dental whitening treatment?
Almost anyone, no matter their age! However, we suggest that dental bleaching only be performed on teeth of which the enamel has reached maturity. In view of that fact, teenagers may have their teeth whitened as long as these have reached stability. We advise against whitening during pregnancy and breastfeeding. Smokers may have their teeth bleached, but they should expect to have to get regular touch-ups, as smoking interferes with the stability of whitening treatments.
Do bleaching results vary from one person to the other?
Results vary depending on each patient’s enamel, which, just like skin pigmentation, is unique to each individual. Excellent results may be obtained when tooth enamel is yellowish or orangey. On the other hand, whitening teeth that have a greyish or blueish appearance is harder and requires more rigorous follow-ups. Discolouration brought on by the use of antibiotics like tetracycline is also difficult to treat. Depending on the degree of colouration, cosmetic treatments like porcelain veneers may prove necessary to obtain the desired results.
Does bleaching teeth alter the surface of enamel?
While a slight deterioration of enamel may be observable under a microscope, it remains imperceptible to the naked eye. It is important to know that the minerals contained in saliva make up for this loss by remineralizing the enamel surface. A rapid loss of calcium does ensue. However it is equivalent to the amount of calcium lost when drinking a glass of orange juice. In short, texture on the surface of teeth undergoes little substantive changes, with the exception of increased porosity that may temporarily bring about a greater adherence of food to teeth. At the end of the bleaching treatment, the surface of teeth becomes the same as before.
What factors influence the efficacy of dental bleaching treatments?
The quality of results obtained depends, first of all, on the type of colouration in question, second of all on the intensity of the colouration, and lastly on the degree of motivation that each patient exhibits in adhering to the prescribed protocol.
Is teeth whitening durable?
Yes. As long as dental bleaching is performed according to prescribed requirements, results will be stable for one to three years. Touch-ups are suggested every six months following treatment, ideally in the days following a patient’s dental cleaning. A few days of touch-ups suffice to maintain the effects of bleaching.
How effective are dental bleaching products sold in pharmacies?
Whitening Toothpaste
Ineffective. The concentration of peroxide is insufficient to make teeth whiter, and the duration of contact between the product and the teeth is too short. However, such a toothpaste may be an excellent adjuvant following a dental bleaching treatment performed at home. These products are effective at completing this process because they successfully remove external stains that may settle back onto the surface of tooth enamel.
Whitening Chewing Gum
Ineffective. It only reduces surface stains.
Whitening Strips
Effective. Reliable and affordable, they work well on teeth that are straight and not overly yellow. However, they present certain disadvantages that make their use somewhat uncomfortable. These types of bleaching systems use polyethylene strips that are placed on teeth. The lower strip tends to be difficult to place and to maintain in place. If you have crooked, crowded or overlapping teeth, the strips will not cover the entire surface of your dentition. Important note: Make sure to protect your gums from irritation or burns that may occur when using this type of product.
Gel Application
More or less effective. This type of bleaching works up to a certain point, but it never goes as smoothly as at-home whitening. If you use these types of gel, avoid swallowing any and make sure they do not come into contact with your lips or your tongue. For any use exceeding fourteen days, your dentist’s supervision is recommended.
What treatment options exist other than products sold in pharmacies?
Three other methods exist for bleaching your teeth:
At-home dental bleaching using a customized mouthpiece
Most often administered in the dentist’s office, at-home bleaching must start with clean teeth. In view of that fact, the patient must first have tartar deposits removed from their teeth, and then have their teeth polished in order to eliminate external stains.
During the first appointment, dental imprints are taken so that custom moulds can be made for the patient’s at-home treatment. The dentist assesses the colour of the patient’s teeth in order to predict treatment results.
During the second appointment, all necessary material and instructions are given to the patient so that they may start their treatment in the comfort of their home. The patient will have to apply a peroxide-based gel on their teeth using the customized mouthpiece, for the prescribed duration as determined by their dentist or dental hygienist.
A follow-up appointment will occur within approximately three weeks of starting treatment.
The patient may keep their mouthpiece for touch-ups, as desired, by obtaining gel during their next dentist appointment at Groupe La vallée.
Advantages of whitening teeth at home using a mouthpiece:
- It’s easy.
- Treatment may be performed at the time of day most suitable for the patient.
- Treatment may be stopped at any time once the patient is satisfied with the colour.
- Treatment can be refreshed at any time. (Touch-ups are recommended following a patient’s last cleaning.)
Disadvantages:
- Course of treatment lasts an average of two to six weeks.
- Results are not immediate, even though certain results can be seen quickly.
- To see results, a patient must scrupulously follow the course of treatment by wearing their mouthpiece every day.
- There is a risk of temporary dental sensitivity to cold and to air during treatment.
- Certain foods and drinks are restricted during treatment, such as products that cause stains, like red wine, coffee, tea, etc.
Dental Bleaching in Your Dentist’s Chair in a Single Visit
This popular method consists in activating the bleaching agent using a high-intensity light called a dental curing light. During this session that lasts approximately ninety minutes, a gel is repeatedly applied to the patient’s teeth in order to obtain the whitest possible colour. The main disadvantage of this method is that it causes extreme dental dehydration immediately following treatment, which makes teeth appear whiter than they actually are. The best way to go about using this approach is to undergo one light activation session, which accelerates whitening, and to then continue bleaching teeth at home by using the mouthpiece provided for at least one week. By combining at-clinic and at-home treatment, patients are able to get the best and most durable results. The mouthpiece wearing period is in this way shortened, thanks to the bleaching acceleration achieved at the dentist’s office.
Advantages:
- Immediate or almost immediate results.
- Perfectly suited to people who do not wish to wear a mouthpiece daily for several weeks.
- Treatment stability is reinforced when combined with at-home mouthpiece wear.
- Shorter food and drink restriction period than with at-home treatment.
- Possibility of performing touch-ups at home, thanks to the customized mouthpiece provided by La vallée.
Disadvantages:
- Higher cost than at-home treatment.
- Treatment is more difficult for patients who have a strong gag reflex.
- Treatment less complete unless optimized using gel with customized mouthpiece for approximately one week following in-chair treatment.
At-home Bleaching Using Prefilled Mouthpiece
This type of treatment is a lesser version of the customized mouthpiece. It consists in applying a standard issue mouthpiece on a patient’s teeth for ten consecutive days. Depending on the bleaching product that you are advised to use, this mouthpiece may be worn from fifteen minutes to two hours each day.
Advantages:
- Less expensive treatment.
- May prove a smart choice for young teenagers.
Disadvantages:
- The mouthpiece being “one size fits all”, it does not perfectly match the shape of all patients’ teeth.
- Possibility of increased gum sensitivity due to the fact that the mouthpiece may not be a perfect fit for each patient’s mouth.
- New prefilled mouthpiece a necessity for each subsequent touch-up.
- Lack of flexibility for patients looking to whiten some teeth more than others.
It is important for bleaching to take place under a dentist’s supervision, no matter the method chosen.
How long is the course of a dental bleaching treatment?
Duration depends on the type of treatment chosen by the patient. Here is some information on various options:
Normal dental colour
At-home treatment – two to six weeks.
In-chair treatment – one session at the dentist’s office, and about one week at home.
Darker dental colour, deep or caused by nicotine
At-home treatment – one to three months.
In-chair treatment – one session at the dentist’s office, and about two weeks at home.
Discolouration caused by antibiotics such as tetracycline
At-home treatment – one to six months or longer.
In-chair treatment – one session at the dentist’s office and about three weeks at home.
Can bleaching my teeth have side effects?
Yes. Among them, the most unwanted side effect is tooth sensitivity. This sensitivity – observed in contact with air, hot or cold food and drinks, etc. – may manifest itself in varying degrees during periods of twenty-four to forty-eight hours during the treatment. In some patients, dental sensitivity persists throughout the course of treatment.
Mild gum irritation is also a possible side effect, which can quickly be eliminated by adjusting the quantity of bleaching product used and by applying it more carefully in the mouthpiece.
What are the long-term effects of dental bleaching?
These vary greatly from one patient to another and depending on each patient’s lifestyle habits. In the majority of cases, the effects of having one’s teeth bleached last from one to three years. Touch-ups are, however, recommended every six months, to keep teeth looking radiant.