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Dental bleaching is commonly known as teeth whitening. This procedure is very common in cosmetic dentistry where the appearance of the teeth is most important. The teeth of a child is whiter compared to the teeth of an adult. As we age, the adult teeth change its color from a whiter shade to a darker shade. The change in color is due to the changes in the chemical composition of the teeth. Our teeth can be stained by the pigments coming from bacteria, foods, beverages and tobacco. Prolonged use of antibiotics is another cause of tooth staining. Tetracycline is an example of an antibiotic that could stain the teeth. There are numerous ways and materials to whiten the teeth, you can use bleaching strips, teeth whitening gel , laser teeth whitening and there are also natural ways to whiten the teeth. At-home teeth whitening kits is done by putting a small amount of whitening gel on trays that resemble a mouth guard.
Chemicals such as hydrogen peroxide or carbamide peroxide are usually used to lighten the color of the tooth. These oxidizing agents penetrate the minute holes in the crystal structure of the enamel. The stains that reside on the enamel are the chemical oxidized or bleached in the process. The use of oxidizer on the teeth over a period of time also oxidizes the dentin layer of the teeth which is just under the enamel. Laser teeth whitening uses the energy of light to catalyze or accelerate the process of teeth whitening. The effects of teeth whitening or teeth bleaching can last of to several months; it all depends on the lifestyle of the patient. Smoking will severely decrease the whiteness of the teeth. Ingestion of dark liquids with natural dyes or food color will also discolor the teeth. Some examples of beverages to avoid are coffee, tea and soda.
Internal staining or staining on the dentine causes the teeth to discolor from the inside out. Bleaching or the use of peroxides can remedy this but if it fails to whiten the teeth, Bonding is usually used. Bonding is a method where a thin coating of a composite material is pasted on the front of the teeth. The composite material has a lighter shade and will mask the discolored tooth. Veneers can also mask tooth discoloration
Teeth Whiteners and Teeth Whitening Products
Various chemical compounds and physical agents are used to whiten the teeth. The common toothpaste contains small amounts of silica, calcium carbonate, aluminum oxide, and calcium phosphate that can grind the stains adsorbing on the teeth. Toothpaste that are classified as whitening toothpaste does not alter the intrinsic or natural color of the teeth. Bleaching solutions are made up of peroxides. Peroxides bleaches the tooth enamel which changes its color.
Home Teeth Whitening
Over the counter teeth whitening products contain 10% to 35% carbamide peroxide in liquid or gel form. These bleaching solutions are safely applied on the teeth surface by the use of a plastic strip that holds the peroxide. Mouthguards with bleaching gel on the insides are also used in some products. The low peroxide concentration on over the counter teeth whiteners makes it only effective after several weeks of use.
home teeth whitening is a very popular method of whitening the teeth. The dentist makes an impression of the teeth and he makes a tray which fits perfectly on your teeth. This tray is then filled with teeth whitening gel, you then wear the tray for up to two hours per day for a period of 5 to 14 days. Most whitening kits given by dentists contain at least 10-15% carbamide peroxide solution. At home teeth whitening is very effective if it is properly supervised by your dentist.
Teeth whitening strips are less effective because these strips doe not perfectly fit your teeth. Most of the time, the area near the gum line does not get bleached.
This procedure is less used and more expensive. In office teeth whitening takes 30 minutes to one hour for every visit. It also takes several visits to achieve the desired whiteness of the teeth. This procedure is more effective compared to at-home teeth whitening because it uses high concentrations of peroxide. The teeth whitening gel typically use between 10-30% carbamide peroxide (15% is recommended) this is roughly equivalent to a 3-10% hydrogen peroxide solution. A protective gel is also applied on the gums to protect them from irritation due to the high concentration of peroxides used in this procedure. Sometimes, light us used for every 5 minutes to activate the whitening agent.
Teeth Whitening Risks
Teeth whitening is considered to be safe when proper procedures are followed. There are certain amounts of risk during any teeth whitening procedure. Teeth sensitivity is a very common side effect during teeth bleaching or teeth whitening. The higher the concentration of the teeth whitening agent used, the higher is the risk of tooth sensitivity. People with gum recession and cracks in their teeth have higher risk of teeth sensitivity.
Gum irritation is usually associated with teeth whitening, more than half of the patients who use peroxide whiteners experience some gum irritation. Gum irritation may persist up to several days; it dissipates after you stop bleaching or if you lower the peroxide concentration.
Hydrogen Peroxide Teeth whitening vs. Carbamide Peroxide Teeth whitening
The bleaching agent that is preferred for in-office whitening is the powerful and fast acting hydrogen peroxide. Hydrogen peroxide is preferred because in-office whitening is time limited. The typical concentration of hydrogen peroxide used during in-office treatment is from 9 to 40 %.
For at home teeth whitening , Carbamide Peroxide is preferred. Carbamide peroxide is slow acting and has about 1/3 the strength of hydrogen peroxide. This is slower acting and less powerful compared to hydrogen peroxide but is considered safer for home use.