Teeth Whitening (Bleaching)


Vital Bleaching

Teeth Whitening

Bleaching result

Bleaching or teeth whitening provides a conservative treatment for mild to moderately discoloured vital teeth or root filled teeth. It is a common procedure in general dentistry but most especially in the field of cosmetic dentistry. A child’s deciduous teeth are generally whiter than the adult teeth that follow. As a person ages the adult teeth often become darker due to changes in the mineral structure of the tooth, as the enamel becomes less porous. Teeth can also become stained by bacterial pigments, foodstuffs and tobacco. Certain antibiotic medications (like tetracycline) can also cause teeth stains or a reduction in the brilliance of the enamel.

Vital bleaching

Bleaching treatment which is done on healthy teeth. There are few methods done for vital bleaching:

  • Non-professional home whitening
  • Professional home bleaching
  • ‘In-office’ bleaching

1. Non-professional home whitening

There are many teeth whitening product sell over the counter in dental store/pharmacy or even online and is much more cost-effective than the in-office procedure: bleaching strips, bleaching pen (eg: BriteSmile To Go whitening pen), bleaching gel, or even whitening toothpaste. Traditionally, at-home whitening involves applying bleaching gel to the teeth using a standard guard trays. At-home whitening can also be done by applying small strips that go over the front teeth. Oxidizing agents such as hydrogen peroxide or carbamide peroxide are used in these products to lighten the shade of the tooth. The oxidizing agent penetrates the porosities in the rod-like crystal structure of enamel and oxidizes interprismatic stain deposits; over a period of time, the dentin layer, lying underneath the enamel, is also bleached.

Whitening Pen

Home kit whitening system

In some whitening toothpastes contain small particles of silica, aluminum oxide, calcium carbonate, or calcium phosphate that used to grind off stains formed by colored molecules that have adsorbed onto the teeth from food. Unlike bleaches, these whitening toothpaste does not bleach or alter the intrinsic (internal) color of teeth.

Whitening toothpaste

Whitening Toothpaste

We have BriteSmile To Go whitening pen

2. Professional home bleaching

Professional home bleaching system

For professional home bleaching (eg. Opalescence, Discuss), clinician/dentist have more control over the usage of the bleaching agent on patient. Usually patient’s teeth will be assess and the expected result should be agree before treatment started. Patient will be prescribed bleaching gel (in syringes)  and a customized bleaching tray and he will be taught to used the product properly at home.

Bleaching Tray

Bleaching gel is dispensed onto the tray and loaded into your mouth

Basically, patient has to clean his teeth before bleaching. Then, the bleaching agent has to be dispensed into the tray and wore it onto his teeth for 8 hours each day for several week (usually 2 weeks). After treatment, he has to brush his teeth again. He has to reduce or stop smoking and the ingestion of dark colored liquids like coffee, tea and red wine as these factors that decrease whitening.

Home bleaching gel contains 10-15% carbamide peroxide. This agent cause less irritation to the gum because it can be contained just on the teeth surface with  custom-made tray. Bleaching result is usually better than the ‘over the counter’ product.

Home bleaching technique
  • Take an alginate impression
  • Ask the laboratory to make a bleaching splint
  • Fit the splint, dispense the carbamide peroxide (10%), and give instructions
  • Advice 6-8 hours treatment per day
  • Review weekly

3. ‘In-office’ bleaching

In-office bleaching  (Eg. ZOOM!! Whitening system) in a treatment done in the dental clinic; usually required patient to be seated on the dental chair for 1-3 hours. Immediately after treatment, patient can see the final result!!. Because In-surgery or in-office bleaching is in total control by the clinician/dentist, the bleaching gels used are highly-concentration (25-38% of carbamide or hydrogen peroxide).  The gel is caustic, hence, protective eyewear and isolation of gum with a resin-based, light-curable barrier required before treatment starts.

Dental light curing lights are commonly needed to activate the bleaching agent. This ‘Light cure’ unit usually use halogen, LED, or plasma to produce light energy to accelerate the process of bleaching. Most in-office teeth whitening treatments can be done in approximately 30 minutes to one hour, in a single visit to a dental physician. Treatment times and recommendations are dependent on the condition of a person’s teeth at time of treatment.

In-office bleaching

‘In-office’ bleaching technique
  • Polish teeth with pumice
  • Isolation of gum/soft tissue with a resin-based, light-curable barrier
  • Etch enamel, wash and dry, although the need to etch has been questioned
  • Apply the bleaching agent according to the manufacturer’s instructions
  • Bleaching gel is activated with light energy from ‘light cure’ or laser unit
  • Wash teeth with copious amounts of water
  • Remove gum/soft tissue barrier and polish teeth
  • Advice patient to avoid tea, coffee, red wine, cigarettes etc, for a week and that some sensitivity may occur
  • Can repeat as required

Case of in-office bleaching using ZOOM whitening system…Click here


Side effects of teeth bleaching include:

  • Chemical burns from gel bleaching (if a high-concentration oxidizing agent contacts unprotected tissues, which may bleach or discolor mucous membranes), sensitive teeth
  • Overbleaching  – noticeable chalk white spot on the bleached teeth which usually lessen in a period of time
  • Pain if you have “sensitive teeth” caused by open dentinal tubules.

The side effects that occur most often are a temporary increase in tooth sensitivity and mild irritation of the soft tissues of the mouth, particularly the gums. Tooth sensitivity often occurs during early stages of the bleaching treatment. Tissue irritation most commonly results from an ill-fitting mouthpiece tray rather than the tooth-bleaching agent. Both of these conditions usually are temporary and disappear within 1 to 3 days of stopping or completing treatment.

Individuals with sensitive teeth and gums, receding gums and/or defective restorations should consult with their dentist prior to using a tooth whitening system. People who are sensitive to hydrogen peroxide (the whitening agent) should not try a bleaching product without first consulting a dentist. Also, prolonged exposure to bleaching agents may damage tooth enamel. This is especially the case with home remedy whitening products that contain fruit acids.

Bleaching is not recommended in children under the age of 16. This is because the pulp chamber, or nerve of the tooth, is enlarged until this age. Tooth whitening under this condition could irritate the pulp or cause it to become sensitive. Tooth whitening is also not recommended in pregnant or lactating women.


In certain cases where the teeth are severely discolour, bleaching treatment might not be the best solution as it not achieve what patient desire. In this kind of situation, Porcelain veneer or full porcelain crown might be a better options.   Therefore, you have to discuss with you dentist and tell him what you really and the pros & cons for each option.

Read more

Causes of tooth discolouration

Non-professional whitening method: BriteSmile To Go whitening pen

In-office bleaching: ZOOM!! Whitening system

Cases with in-office bleaching

Cases with in-office bleaching (II)

Non-vital bleaching

Porcelain Veneer or Full porcelain crown

Tooth Crystal

This entry was posted in Aesthetic Dentistry by Dr. Ng SN. Bookmark the permalink.
Dr. Ng SN

About Dr. Ng SN

Dental Surgeon BDS (MU) Dr. S. N. Ng is a general dental practitioner. She graduated from University of Malaya in 2003 and has more than 15 years of working experience as a dental surgeon. Her previous working experience includes working as a dental officer in government health clinics and private clinics. She mainly specializes in orthodontics treatment, cosmetic dentistry including teeth whitening/bleaching, aesthetic composite filling, crowns and bridges.

4 thoughts on “Teeth Whitening (Bleaching)

Leave a Reply

Your email address will not be published. Required fields are marked *