Teeth Whitening (Bleaching)
Teeth whitening (bleaching) of discoloured teeth is cheaper, more practical and harmless compared to other restorative methods. Teeth whitening is a cosmetic solution recommended for people who are not satisfied with the colour of their teeth.
Teeth whitening is the process in which the bleaching agent penetrates into the enamel and dentin, where it creates an oxidation reaction and releases the molecules that cause discolouration until the teeth are whitened.
The natural colour of teeth darkens with years and external factors. With the teeth whitening
process, which can be done in the clinic or at home, the teeth are lightened by 2-10 tones and a satisfactory whitening and a beautiful smile are obtained. Bleaching procedure must be applied under professional control.
Mechanism of Dental Whitening
In dental bleaching, hydrogen peroxide first diffuses into the organic matrix of enamel and dentin. Since the electrons of free roots are unpaired, they are electrophilic and unstable. In order to become fixed, these roots act on the unsaturated carbon double bonds of organic molecules, causing a break in electron conjugation.
The absorption energy of enamel organic molecules changes. These molecules are lighter in colour. Thus, initial whitening of the enamel is obtained. After the initial whitening, the pigment-containing carbon chains are spaced and lighter coloured chains are formed. The carbon double bonds, which are usually yellow pigmented, change to colourless hydroxy groups such as alcohols.
As bleaching progresses, a point is reached where only hydrophilic colourless structures remain. This is the enamel saturation point. The bleaching then slows down and if the process continues, it starts to break down the carbon skeleton of proteins and other carbon-containing substances. Enamel loss begins and the remaining substance turns into CO2 and water.Therefore, the dentist should calculate the saturation point very well.
Teeth Whitening Methods
Home Teeth Whitening Method
The dentist takes impressions from the mouth and prepares thin rubber moulds that can be worn on the teeth to be whitened. The medicine is placed into the special mould prepared individually. This medicated mould is worn on the teeth to be whitened for at least 6 to 8 hours a day. In this way, teeth whitening is performed.
Office Type Teeth Whitening Method
The tooth whitener is placed on the tooth by an experienced dentist. The white coloured light source is kept on the tooth to be whitened for a certain period of time. In this whitening method, the result is visible immediately after the procedure. In addition, this method also includes whitening of single tooth discolouration caused by various reasons from inside the tooth.