There are various methods of whitening the teeth:
1.) Home bleaching technique
2.) Dental office bleaching
3.) Whitening toothpastes
Carbamide peroxide in concentrations of 10,15 or 20% is loaded into custom made trays to fit the teeth. The trays are snug fitting for an individual's mouth and help to hold the bleaching gel in close contact with the surface of the teeth to be bleached. It involves wearing the trays overnight for about 4 to 5 nights for the teeth to lighten up by 2-3 shades.
The process can be repeated after 6 months or a year, as and when needed using the same trays, topping up with a new syringe of gel.
It takes 2 visits to the dentist. In the first visit the dentist would make impressions of the teeth to fabricate the trays. In the second visit the trays with tubes of bleaching gels would be dispensed. The existing shade of the teeth is noted for comparison at a later date.
As a side effect the teeth may get a little sensitive temporarily while the bleaching is being done and then usually settles down fairly quickly. A desensitizing paste or mouthrinse can be used to minimize the discomfort.
Dental Office Bleaching
In this 35% hydrogen peroxide is used. It is unsafe to use such high concentration at home. A considerable change in color is achieved in one visit at the dentist using this technique.
The dentist would isolate the teeth using a gingival barrier to protect the sensitive soft tissue from coming in contact with the gel. A layer of bleaching gel is applied to the teeth and allowed to remain for about 12- 15 minutes.An activating light may be used on the teeth to gain effect of the gel. The gel is then wiped off and the process repeated 2-3 times as needed. The teeth can get temporarily sensitive but the shade is lightened in one visit.
These are commercially available pastes which contain mild abrasives to rub off the surface stains but do not have any active contents that chemically act to lighten the teeth.
This is not active bleaching.
Before any method of bleaching it is vital that the teeth be cleaned and polished to remove any obvious tartar. Where teeth have yellow green bands due to tetracycline staining, or opaque chalky white bands / spots due to fluorosis, bleaching may not be very effective. In these cases the teeth would have to be veneered or crowned to mask the discoloration.
When a single tooth has darkened because of dying or dead tissue within, it can be lightened by a different method of individual tooth bleaching. In this the tooth has to be first root treated and then packed with a bleaching agent for a couple of weeks to get the desired results.
Whatever the cause of discoloration in teeth there is usually something that a dentist can help you with to get your smile bright and you feeling confident.
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