Some time ago we reported in a short article about bleaching, the whitening of teeth. However, this topic is so topical for a large number of readers and patients that we will take it up again in this report and describe it in more detail. Numerous enquiries on this subject show that there is still a high need for information on the part of patients.
Bleaching – tooth whitening without risk
Why roam through life with yellow teeth when white teeth are feasible for everyone and whitening can be done without great risks? Bleaching has been a high priority in the USA for many years. But the whitening of teeth does not belong in the hands of beauticians, but in the hands of the dentist. Only then is it guaranteed that the whitening of the teeth does not cause any permanent damage. This may be more expensive in the beginning, but it always pays off for the patient.
Determination of tooth colour
First, the tooth colour is determined, usually with the help of the Vita colour ring. Both the brightness of the tooth and its shade concentration are determined. The colour scale used to classify the tooth colour also differentiates between the colour composition, which is marked with a letter, and the brightness, which is indicated with a number. This shade scale can also be used to determine the maximum brightness that can be achieved for the respective tooth or how successful a whitening procedure has already been. If a patient already has a tooth shade that corresponds to the A1 shade guide, further whitening is hardly possible.
If, on the other hand, the tooth colour is A3 – actually the most frequently occurring natural tooth colour – a whitening of up to 7 shades is possible. The maximum achievable whitening always corresponds to the smallest number of the patient’s colour group. For example, whitening is possible from A4 to A1 or C3 to C1. However, the colour composition of the tooth colour cannot be changed. A patient who previously had a tooth color of the A group (reddish) can only remain in the A group.
The color of the tooth is determined by color pigments in the dentin of the tooth. Later, external influences such as drinking coffee, tea or smoking add further colour molecules. These color pigments are not only deposited on the surface, they can even partially penetrate the enamel and accumulate in the dentin. The fewer colour pigments there are, the more colourless and thus whiter the tooth appears to the observer.
How does bleaching work?
In bleaching, a chemical substance with hydrogen peroxide as the most important component acts on the cleaned tooth enamel. It is usually ceramide peroxide, a mixture of hydrogen peroxide and urea. This substance penetrates into the dentin and destroys colour pigments by oxidation. Ultimately, only colourless, oxidized molecules without a colouring effect remain in the dentin.
The duration of application depends on the desired brightening. After 14 days a whitening effect of approx. 7 scales is achieved.
Due to the very long exposure time of the bleaching agent, this form of bleaching is also carried out at home (home bleaching). Homebleaching, however, is a teamwork of prophylaxis assistant, dentist and patient.
First of all, the basic requirement is professional tooth cleaning by the prophylaxis assistant. Only then can the real natural tooth colour of the patient be determined. The dentist then checks existing fillings for tightness and then determines the most appropriate target tooth colour to be achieved.
The prophylaxis assistant now takes an impression of the patient’s tooth pattern so that a thermoforming foil can be made for the patient in the laboratory. This thermoforming sheet is now integrated by the dentist and it is he who instructs the patient how to wear it.
Now it is up to the patient to wear this foil at home together with the bleach. In between, the dentist checks the correct application of the bleaching by the patient during a control session. The patient continues to wear the foil until the bleaching time has elapsed.
Finally, the dentist checks the result of the treatment and, if necessary, renews old fillings, because bleaching does not change their colour to the same extent as the teeth, but they usually remain dark.
Are there any risks from bleaching?
First of all, it remains to be seen that both vital and pulpenotic teeth can be bleached. A large number of studies prove that bleaching is harmless. However, a temporary reversible pulp reaction of the teeth can occur. For the patient this means that his teeth are sensitive to heat and cold for a while. A reaction that occurs as described, but only temporarily.
Further information on bleaching
The brightening is not paid for by the health insurance companies. It is a purely private service. Therefore, the costs have to be agreed with the dentist. The accounting is carried out according to GOZ paragraph 2, paragraphs 1 and 3. It must be calculated from an economic point of view, whereby the simplest method of accounting is time consumption. A dentist’s hour costs about 190 euros on average. Besides the material consumption must come to the account (§10 GOZ).
In Germany, an average of between 124 and 250 euros per jaw is calculated for a whitening of the dental row up to the 2nd premolar.