There have been attempts to whiten teeth in the affluent classes for centuries. Until now, agents have often been used that had no effect, damaged teeth or were impractical ( urine from humans and animals, acids , various other chemicals). Today teeth can be whitened effectively, practically and gently. Most studies show that, provided that pH-neutral preparations are used and properly applied, no tooth damage is to be feared with tooth whitening and side effects are limited.
Who can bleach?
Patients and trained staff may use products with a maximum of 0.1 percent hydrogen peroxide content as teeth whitening agents that contain hydrogen peroxide. The applications with higher peroxide concentration are carried out by dentists. NeEU Cosmetics Regulation.
Reasons for teeth whitening
A distinction is made between bleaching measures that are carried out for medical reasons (which also include dental aesthetics) and cosmetic improvements.
Bleaching for medical reasons
Bleaching of teeth that have an unnatural appearance due to tooth enamel defects can be medically indicated. Teeth that have undergone root canal treatment and which have become dark due to their devitality may also be indicated. Coloring substances may have been incorporated into the tooth enamel and dentin , which should be improved by bleaching. There may be a medical need for psychological reasons: Tooth discoloration can be stressful.
As with most cosmetic interventions, the current ideal of beauty or “deviations” from it are motivating for the patient . Cosmetic whitening is used to lighten a natural but darker tooth color. Services that are provided without a therapeutic objective are - in contrast to medical treatment - subject to sales tax. For these services, sales tax must be reported to the patient as part of the billing, unless the exception for taxation as a small business owner according to UStG comes into consideration.
By bleaching, the natural tooth color can be lightened by about one level on the color scale.
Causes of tooth discoloration
Tooth discoloration can arise from the outside as staining foods and luxury goods such as alcoholic beverages , tea , tobacco smoke , coffee , red wine , fruit juices, etc. penetrate the tooth. Or they arise from within as a result of the effects of medication, as a result of accidents, tooth decay , death of the tooth pulp , malnutrition , etc.
It has been known for some years that tooth enamel (and gums) can be damaged if teeth are exposed to acidic foods (e.g. juice or nectar, fruits such as bananas, pineapple) immediately after ingestion , Oranges, etc.). Therefore, after eating these foods, the mouth should initially only be rinsed out with clean water and cleaned for a few hours so that the teeth can remineralize themselves.
Differentiation from plaque
Tooth discoloration differs from plaque in that coloring substances have been deposited in the tooth enamel and dentin below the tooth surface. External teeth cleaning can no longer achieve these dyes.
Before a whitening treatment , a dental examination of the teeth for tooth or gum damage must be carried out. In addition, professional tooth cleaning (PZR) is indicated, since on the one hand the actual tooth color can only be assessed with a tooth that is free of plaque and on the other hand the bleaching agents can have a better effect on the tooth substances.
Duty to provide information
According to information .BGB, bleaching requires the fulfillment of the medical
“The treating person is obliged to inform the patient about all of the circumstances that are essential for the consent. This includes in particular the type, scope, implementation, expected consequences and risks of the measure, as well as its necessity, urgency, suitability and prospects of success with regard to the diagnosis or therapy. When providing information, it is also necessary to point out alternatives to the measure if several medically equally indicated and common methods can lead to significantly different burdens, risks or chances of recovery. "
The information must be given orally, personally and in good time before an intervention so that the patient can think about his decision sufficiently. With regard to bleaching, this includes information about repetitions that may become necessary or about possible color deviations, in particular about dentures and fillings .
Preparations that contain hydrogen peroxide (H 2 O 2 ) (e.g. in the form of carbamide peroxide or urea peroxide) are generally used for teeth whitening . They can penetrate the tooth and split off oxygen radicals there . These are able to chemically change dyes in the tooth so that they no longer appear in color. Tooth whitening products should have a neutral pH value so that they do not roughen the teeth and thus promote renewed discoloration. Different methods are used:
Lightening with individually manufactured aligners ("home bleaching")
For the patient - after taking an impression of the teeth and making the model - the dental practice or their laboratory deep-draws and cuts a precisely fitting plastic splint that covers the teeth. For teeth whitening, this splint is filled with whitening gel containing peroxide . The home bleaching gel usually has a concentration of 10 to 20 percent peroxide. Depending on the concentration and the individual situation, the patient wears these splints for between one and eight hours. In the case of "age discolorations", five to seven treatments are often sufficient, in the case of more stubborn discoloration, e.g. B. Tetracyclines often 15 or more treatments are necessary. Home whitening is especially indicated when the entire dental arch is to be whitened.
Lightening through direct application ("Power Bleaching" or "In-Office Bleaching")
With in-office whitening, preparations with a higher concentration are used in the dental practice. In preparation, the gums are protected (covered) with a rubber-like coating, the "rubber dam", or a flowable material (usually on a composite basis), the "gingiva protector". The dentist applies the whitening agent directly to the teeth to be whitened and acts there. Sometimes the effect is intensified by exposure to light with bleaching lamps. The latter is done with bleaching gels, which are chemically activated by the action of short-wave light (cyan / blue or UV light). After 15-45 minutes the gel is removed. If the lightening is not sufficient, the procedure can be repeated. As a rule, one or two treatments are necessary for a first-time teeth whitening in order to achieve a permanent result (one year and longer). Power bleaching is usually chosen when it comes to whitening individual vital (living) teeth or when bleaching is to be accelerated.
Whitening through deposits in the tooth ("walking bleach technique")
If a single, devitalized (dead) tooth is whitened, this can also be done with an insert in the tooth. To do this, the crown of the tooth is opened. This has already been drilled out through the previous root canal treatment . A suitable agent is introduced into the pulp cavity, the earlier the pulp ( pulpa dentis has completed). The tooth is then temporarily closed and the whitening agent is left in the tooth for one or more days. After removing the whitening agent, the opening is filled again. It takes a few days for the peroxide to diffuse from the inside of the tooth through the tooth enamel. The lightening is therefore delayed. If the tooth color achieved does not match the desired result, the method can be repeated.
Effect of the whitening agent on fillings, crowns, bridges
The color of tooth fillings as well as veneers of tooth crowns and bridges are not changed by tooth whitening. Therefore, it may be that they have to be renewed in the visible range after whitening, a serious because costly decision on the scope of which the patient be aware of needs, especially since no whitening is permanent and again in color between the natural teeth and dentures occur can. The dentist must inform the patient about this. A professional teeth whitening before the re-insertion of dentures brings the same problem with it. In these cases, too, the patient must be informed that teeth whitening will have to be carried out from time to time in order to avoid color differences.
- Already during the treatment there is often a very painful sensitivity to the bleach. Freshly treated teeth can be sensitive to sweets and sour and temperature sensitive, which can be very painful. However, these symptoms are usually only temporary and subside within a few days after the treatment.
- Activation of bleaching agents by heat, light, or laser remains controversial and dentists should continue to review the evidence for these procedures as they can damage pulp tissue.
- The long-term effects of higher concentration bleaches (> 6% H 2 O 2 or equivalent) on the pulp, dentin, enamel and oral soft tissue are not yet understood. These bleaches are potentially harmful and should only be used with caution in the dental office.
- If the tooth whitening agent used has a pH value of ≤ 7.0, the tooth substance can be roughened on the surface by bleaching. Tooth whitening materials are therefore used in the pH-neutral range.
- During the whitening treatment, the color pigments in the tooth enamel are changed by oxidation, which causes the whitening. Numerous studies have examined whether whitened teeth are rougher, more brittle or more prone to caries. Most studies show that the whitening treatment is harmless when performed properly. Preparations containing fluoride and potassium nitrate have been found to have a caries-protecting effect.
- Whitening can remove minerals from the teeth, which can lead to both demineralization and the temporary breakdown of the protein pellicles (the protective layer of the tooth). This can lead to more or less covering white spots, which normally return to normal in the days after the treatment. The remineralization can be supported by special gels.
- The tooth structure can be weakened by bleaching. Internal bleaching can lead to brittleness of the tooth and root resorptions.
- If the bleach gets on the mucous membrane, there is a risk of mucous membrane irritation.
- It is estimated that around 25% of the whitening gel is swallowed during home teeth whitening, which can cause health consequences such as irritation of the mucous membranes in the mouth, throat and stomach. Normally, the bleaching trays seal very well - the above estimate is based on the typical overdose of the bleaching gel by home users. As part of in-office bleaching, swallowing can be avoided by continuously sucking off the saliva.
Durability of teeth whitening
The following applies to all commercially available methods: Teeth whitening does not last forever, but often for years. The durability of the result depends largely on the quality and quantity of oral hygiene, the individual consumption habits (especially coffee, tobacco and tea) and on the fact whether professional teeth cleaning is carried out regularly and then enamel hardening agents are used. As soon as the whitened teeth become noticeably darker in whole or in part, the bleaching must be repeated in order to achieve renewed whitening. Refreshing treatments are usually much gentler than the initial bleaching, as a smaller amount of peroxide has to be used due to the pre-bleached teeth.
In addition to "office whitening" or "home whitening", there are preparations in the free trade (pharmacies, drugstores and supermarkets) that can be used by the patient, including brush solutions, coated adhesive strips and prefabricated splints with pastes and gels. These funds vary in quality. Sometimes there are agents that can damage the teeth, lead to insufficient or uneven whitening or irritate the gums. The main problem with self-treatment, however, lies in the lack of prior, appropriate diagnostics: the layperson cannot assess the reasons for the discoloration, which may mean that important pretreatments (caries removal, root canal treatment ) are omitted and undesirable color deviations may result.
Teeth whitening costs
The costs for the teeth whitening are not covered by the statutory health insurances , because the service does not meet the economic efficiency requirement according to SGB V , according to which “ services must be sufficient, appropriate and economical; they must not exceed what is necessary. Services that are not necessary or uneconomical can not be claimed by the insured, the service providers are not allowed to provide and the health insurances not approve ". The dentist creates a private treatment and cost plan from which the individual costs can be seen. They amount to between 300 and 600 euros for both jaws. The fees for bleaching individual teeth vary between 20 and 50 euros per tooth.
- The bleaching of discolored teeth. Scientific opinion of the German Society for Dentistry, Oral and Maxillofacial Medicine
- Teeth Bleaching Materials Opinion from the FDI World Dental Federation
- Teeth Whitening with Hydrogen Peroxide - Summary of a Report by the Scientific Committee on Consumer Goods of the European Commission
- Josef Schmidseder: Healthy and beautiful teeth . Südwest-Verlag, May 2002. ISBN 3-517-06151-4
-  Stiftung Warentest: White teeth - what really whitens teeth . January 2013.
- Stephan Berg, Norbert Schmitz-Koep: Beautiful teeth . Honos Verlag, September 2001. ISBN 3-8299-5548-0