|
No matter how much we take care of the teeth, they discolour with age. Whilst coffee and red wine are the main culprits, eating a healthy diet rich in colourful foods and tannins (=antioxidants) also means that they will discolour quicker. The outer covering, the white enamel, is porous and allows colour to enter and discolour the underlying dentine. It is the dentine that gives the colour to the teeth; the enamel adds the luminosity, shine and depth of colour.
Some colour may also come from within; tetracycline and fluorides are also known to stain the teeth from the bloodstream. This may be more difficult to bleach out; more treatments may be required and home use kits recommended.
The bleaching agent is hydrogen peroxide, used in the military as mouth wash and still used as a therapeutic dental agent today. In fact tooth whitening was created after dentists remarked upon the whiteness of the teeth of service personnel. Hydrogen peroxide breaks down to form water and oxygen, in the process the free oxygen attaches itself onto the coloured stain molecule rendering it invisible. Nothing is washed out of the teeth. They are not weakened in any way. It is this remarkable safety aspect that allows us to perform teeth whitening in the clinic.
Artificial teeth, implants and fillings do not respond to whitening; otherwise just about everybody can benefit from this treatment.
First of all we paint a layer of protective gel onto the border of the gums and the teeth. This is "cured" with a light and serves to protect the gums from the peroxide. Then the 35% solution is painted onto the teeth. In order to accelerate the process, blue light (a cold, non-heating light) is shone onto the gel. This liberates the oxygen, which enters the enamel and becomes incorporated into the stain molecule, removing its colour. Once ten minutes have elapsed, the gel is removed and another fresh application made. A further ten minutes and then one more ten minutes completes the process. The teeth will have lightened several shades.
During the procedure there may be some sensitivity. This is due to accumulation of microscopic amounts of oxygen gas in the architecture of the teeth. Even a few molecules of oxygen will create pressure in the teeth, which is sensed by the pressure sensors at the bottom of the teeth. This is perceived as pain but in no way correlates to tooth damage. This sensation may continue after the treatment and can easily be remedied by simply brushing with a fluoride toothpaste. Fluoride acts as a numbing agent. We provide you with a high fluoride toothpaste for before and after the treatment in order to minimise post-treatment sensitivity. In fact, continued discomfort reassures you that the peroxide is still working!!
The whole process takes about one hour, with the mouth being held open with a plastic retractor only for 40 minutes. It is not uncomfortable and you may ask the therapist to stop at any time.
The protective biofilm naturally found on the teeth is restored within 20 minutes, so in theory you may eat and drink normally immediately after the treatment. However, the peroxide is still active until the next day so for the very best whitening we advise you to eat only white foods for the next 24 hours (cauliflower cheese, banana and apple; plain yoghourt or porridge for breakfast). |