What is teeth whitening?
Tooth whitening is the highly effective way of lightening ones natural tooth colour without the removal of any tooth structure. Our tooth colour varies just like hair and skin colours vary. Teeth discolour as we get older and also get stained as we consume food and drink such as tea, coffee, red wine and smoking.
What are tooth stains?
Teeth are made up of an inner layer called dentin and a hard outer layer called enamel which protects the tooth. When food, tea, coffee and cigarette smoke enter the mouth another layer forms on enamel. This layer of foreign material is the pellicle layer.
As time goes on, this foreign material gets into the enamel. The enamel layer is made up of hydroxyapetite crystals which form microscopic hexagonal rods, in other words enamel is porous. Staining agents are therefore able to penetrate the tooth structure which cannot be scoured away with conventional cleaning methods. Tooth whitening uses bleaching chemicals to get down into the enamel and set off a chemical reaction breaking down the staining compound.
How effective is tooth whitening?
No dentist can be able to unconditionally guarantee that you will be pleased with the outcome of your tooth whitening.
Before and after a basic cleaning & whitening This is because many people have unrealistic ideas of what is a natural tooth shade. One must always bear in mind that an expectation of bleaching ones teeth to an unnatural level of whiteness can be expected to fail.
Some teeth bleach well while others are less successful. You will only know the degree of effectiveness of bleaching once you try it.
What materials are used?
Usually the active ingredient is hydrogen peroxide or carbamide peroxide. As the active ingredient is broken down, oxygen gets into the enamel and the tooth is made lighter. The discoloured areas are bleached out.
What types of tooth whitening are there?
• Chairside professional bleach
• At home bleaching
• Chairside laser bleaching
• Over the counter agents
• Tooth whitening toothpastes
What is chairside tooth whitening?
This form of whitening takes place in the dental chair usually using a 15-35 % hydrogen peroxide. Sometimes a strong light is used to expedite the bleaching chemical reaction. The use and effectiveness of this light is however, questionable.
The teeth need to be cleaned first and a protective coating is placed onto the gums to protect them from the bleaching agent. The eyes need to be protected as well. The paste is placed onto the tooth surface for several minutes and then rinsed off. The paste is then reapplied several times. The entire procedure usually lasts for about 45 minutes.
The procedure can be uncomfortable and is relatively expensive.
It should always be followed by at home whitening to enhance the effect.
What is the home tooth whitening?
This procedure is done by the patient at home under supervision of the dentist. Firstly impressions are taken of the teeth so that a soft custom made mouth tray can be fabricated. Once ready, the patient will receive the trays, enough bleaching agent and instruction on how to do the bleaching. Some follow up appointments are made so as to monitor progress. The bleaching agent is usually 10-20 % carbamide peroxide. A thin amount of gel is placed into the trays and these are inserted into the mouth. Any excess material is removed with the finger. Usually only one jaw is whitened at a time so that the other jaw will act as a control.
Treatment usually lasts 3-4 weeks.
It is much more comfortable as well as cheaper than the chairside procedure.
What is over the counter tooth whitening?
Low concentration peroxides are usually used. Some contain mild acids that can cause ulcers and gum damage. These are usually ineffective and do not allow for professional monitoring.
This procedure is not advisable.
What is tooth whitening toothpaste?
They are usually quite abrasive and only tend to remove surface stains. They can damage tooth structure leading to eventual deterioration of enamel and even further darkening of the tooth.
How does treatment start?
A complete clinical examination and screening is done first to determine good dental health. The existing shade is documented and photographs are taken. Oral hygiene should be done as well as any restorative work. The history of a patient’s lifestyle is important so as to ascertain what might be consumed –this might help shed light on the causes of the staining.
How long does it last?
Effects usually last up to 3 years. It does however, vary from person to person. Smoking and certain foods and drink may lessen this time period.
If it regresses it is easy to top up for a few days.
What are the side effects?
The teeth sometimes become more sensitive to hot and cold things during and after treatment. These symptoms are usually temporary and disappear after the treatment has stopped. Gum irritation may also occur. Some less common side effects are sore throat, toothache, tingling of oral tissues
Very rarely are the symptoms severe enough to discontinue treatment.
Is tooth whitening safe?
Most studies confirm that tooth whitening is safe and effective. Studies show minimal or no effect on the microhardness or mineral content of enamel. It causes no damage to fillings or nerves. Safety during pregnancy is unknown therefore it is advisable not bleach at this time.