Teeth whitening is a very simple, highly effective and non-invasive method of lightening the colour of your teeth.  The home whitening procedure is the most effective and predictable method of whitening teeth and gives consistent results. It is essential that you follow the instructions given to you by your dentist with regards to wearing the trays and applying the bleaching agent. The end result is a brighter, whiter smile. Restoring your teeth to their natural whiteness, effectively takes years off your appearance. The procedure takes 3-4 weeks on average. Darker teeth can take up to 4-5 weeks or longer.


Tooth discoloration can be internal or external. Over time , the natural ageing process can give rise to darker teeth. The outer white translucent layer ( Enamel) progressively thins out and the inner yellow layer ( Dentine) gradually darkens. Your lifestyle habits too can stain your teeth. Dietary habits ( such as drinking coffee, tea and red wine, consuming curries, red berries and other dark pigmented food products, as well as smoking are all combined factors ). Medication ( such as tetracycline), excessive ingested fluoride, metals and blood disorders can also cause tooth discoloration.


Two appointments are necessary to whiten your teeth:

Appointment 1 : An impression ( copy of your teeth) to fabricate the custom made trays.

Appointment  2: Delivery of whitening chemicals, instructions on use and shade verification ( if necessary).

The dentist can advise you if a follow up appointment is necessary.


  1. The active whitening ingredient is Carbamide Peroxide , in a glycerine base which is inserted into the trays to whiten the exterior surfaces of the teeth. The custom made trays closely fit over the teeth and are thin, unobtrusive and comfortable to wear. If you know of any allergy or are aware of an adverse reaction to Carbamide Peroxide, please do not proceed with this treatment. The chemical whitens the teeth through an oxidation process by increasing the teeth’s permeability to oxygen, which then breaks down stain molecules. It is a safe procedure and does not damage or remove any tooth structure.


  1. As with any treatment there are risks and benefits. The benefit is that teeth can be whitened fairly quickly, in a simple and safe manner. The risk is transient teeth and gum sensitivity which is only associated with the whitening process. Most people experience some degree of transient tooth sensitivity as it takes 3 days for the hydrogen peroxide to penetrate the teeth to the maximum depth. Sensitivity is usually most profound within the first 3 days of the whitening procedure. It subsides once the whitening is completed. If sensitivity becomes too uncomfortable, refrain from using the bleaching product for 1-2 days or take painkillers. If whitening must cease for 2 days due to sensitivity, please resume as quickly as possible. The degree of sensitivity does vary per individual. Safety studies have shown that bleaching teeth using the dentist prescribed home bleaching kit is perfectly safe on the teeth, cheeks, gum and tissue of the mouth. There are problems with bleaching kits that are purchased over the counter in commercial shops. Although they are inexpensive, they are not as effective, with some products being quite harmful. Some contain an acid rinse, which can damage the teeth or thin down the enamel of the teeth wearing away the polished enamel lustre.


  1. The amount of whitening varies per the individual. It depends on the amount of colour lightening personally desired and the original shade of the teeth. Night whitening involves wearing the trays at night during sleep. Saliva can marginally wash away or dilute the whitening agent but as salivary flow is reduced during sleep, the end product is a more successful result.

Teeth that are very dark, yellow/gray or tetracycline stained, will take longer to whiten.  Discoloured teeth which have become darker over time from being root treated can be lightened by applying the whitening chemical to the inner surface of the tooth. In both cases, the procedure needs to be continues until the desired shade is reached.

Tetracycline stained teeth can take up to 4 months to bleach. Most teeth whiten after 3-4 weeks. It is the manufacturer’s recommendation to avoid tea, coffee, red wine, red berries and curry during and after treatment for at least 2 weeks to achieve optimal results. It is also advisable not to smoke during the course of the treatment.


  1. Teeth with congenital white spots ( hypo-calcification) prior to bleaching, will appear whiter during the first few days. After whitening is completed, the contrast between the white spots and the rest of the mouth will be less and eventually they will not be noticeable ( usually 2 weeks post whitening).

Some people may notice a few white spots occurring on the teeth while undertaking the treatment. These white spots were already present on the teeth before bleaching, but as the teeth become lighter they become more visible. Do not worry. As the whole tooth itself becomes lighter ( as above) these spots will fade. You may notice these white spots  in the morning if you have been wearing the trays overnight.

Some teeth may even appear banded with lighter/ whiter areas. Again these bandings are originally present in the tooth structure. When teeth are darker, these bands are not obvious. As the teeth become lighter, the lighter parts of the teeth will lighten first followed by the darker banded area. After 2 weeks these will not be noticeable any more.


  1. Do not use the bleaching treatment if you are pregnant. There have been no adverse reactions reported, but long term clinical effects are unknown.


  1. After the desired amount of teeth whitening has been achieved, keep the trays for top up treatment in the future ( usually 3-4 nights top up every 6 months depending on your lifestyle habits). The trays should be retained in their box in a safe place of storage kept away from pets, heat or direct sunlight which may damage or distort the trays. Re-application of whitening is necessary in the future to maintain the results as the effect of whitening is not permanent due to the effects of ageing and lifestyle habits.


  1. Whitening only works on natural teeth. Existing fillings, veneers, crowns, bridges and dentures will not change colour and will require replacement in some circumstances after your desired colour has been achieved, especially if the restorations are in the aesthetic smile zone.


  1. There are no guarantees as to the amount of lightening that can be achieved during the bleaching treatment. Please remember the practice of medicine is not an exact science. Different people can react differently to a procedure. The results of whitening can be more effective with some patients more than others.. Further treatment may sometimes be necessary to lighten the teeth. These options may include extra product time whitening, micro abrasion, porcelain veneers or crowns.


  1. Procedure

Teeth must be thoroughly cleaned before the whitening process ( brush and floss). The teeth must be dried with a flannel prior to inserting the trays to remove excess saliva. A lentil sized amount of whitening gel is applied to the tray fitting the exterior surface of the teeth. It is very important to remove all the excess material around the gums after inserting the trays to avoid a chemical burn on your gums ( mild irritation/ soreness which subsides after 24 hours). Nothing should be consumed by mouth ( food or drink) once the trays have been placed. Always clean the trays under cold water with a toothbrush and toothpaste. Cold or tepid water must be used to prevent heat distortion to the trays as they are made out of acrylic.  Discontinue treatment should any problems occur and notify your dentist.



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