What is the tooth whitening process?

What is the tooth whitening process?

Do you restrict yourself from smiling due to darkened teeth? Are you looking for a dental treatment that can help you get a natural, brighter smile? Well! Then you must consider undergoing a tooth whitening procedure to get a brighter smile. Tooth whitening has become one of the most demanding dental procedures by people all over the world. The demand for whiter, more perfect smiles has led to the development of various tooth whitening agents. These include treatment products like toothpaste, films, gels as-well-as in office-based systems where certain bleaching agents are used for treating tooth under professional supervision.

Table of contents

  1. Introduction about dental treatments
  2. What is tooth whitening
  3. Why the colour of tooth changes?
  4. What is the procedure for tooth whitening?
  5. When do you need to see a dentist for tooth whitening?
  6. Is it permanent process or require regular treatment?

2. What is tooth whitening?

Tooth whitening is a process carried out to lighten the colour of the teeth. Tooth whitening process may be accomplished either by physical, or chemical process. Both the processes aim at removing the stain from the teeth to lighten the tooth colour. 

How does it work?

Tooth whitening procedures involve the use of peroxides or bleaching agents. Bleaching agents promote the degradation of the chromogens. Chromogens are tooth staining compounds that have color or are in darker shades found accumulated in the tooth or on the surface of the tooth. Chromogens or tooth stain compounds are of two types:

  1. Large organic chromogens-  These compounds consists of conjugated double bonds in their chemical structure. These double bonds tend to oxidize when treated with tooth whitening agents due to the presence of hydrogen peroxide. The oxidation reaction makes the chromogen a lighter colored compound.
  1. Metal containing chromogens–  It’s difficult to bleach the metallic compounds with tooth whitening agents as it may not produce the desired results. In such cases, products containing sodium hypochlorite (NaOCl) solution can help that reacts with the double bonds of the chromogen. Some other esthetic options may include veneers, crowns or bonding.

Tooth whitening process is usually carried out as an office-based method or at-home- care. Both procedures use peroxide-based bleaching agents where the at-home-care systems contain 3-20% of peroxide agents (like the carbamide or hydrogen peroxides) and 15 – 43% percent in office-based systems.

It’s also important to note that the stronger the solution strength is, the lesser the time it should be applied on your teeth. Also, keeping the tooth whitening agent on your teeth for longer periods will dehydrate the tooth and increase your tooth sensitivity. Not everyone is likely to see the expected results and especially bleaching agents will not whiten porcelain crowns or composite tooth bondings. This is why it’s important to talk to your dentist before you try at-home tooth-bleaching kits. 


3. Why does the color of the tooth change?

The luminosity of your teeth can fade away due to various reasons. Some of which are listed below:

  1. Dietary and lifestyle habits: 

Foods/drinks: Drinks like Coffee, tea, wines, colas,and foods that are high in starch content like pasta, chowmein contains a lot of pigment producing-producing substances called chromogens. These foods are also rich in tannins, which act as adhesive agents to those chromogens. 

Tobacco use: Smoking or chewing tobacco can stain teeth. The nicotine content in tobacco and tar produced from the tobacco smoke can cause yellow or stained teeth.

  • Unhygienic dental conditions: Not brushing and flossing your teeth regularly can cause plaque build up on the tooth surface. Skipping teeth cleanings may also cause food stain build up.
  • Disease: Suffering from certain diseases like diabetes, and cancer, can prevent normal development of tooth enamel and dentin which in turn may lead to tooth discoloration. Medical treatment which involve radiation and chemotherapy can also cause teeth discoloration.
  • Medications:
    • The antibiotics like tetracycline and doxycycline – These drugs affect enamel formation in children under the age of 8. 
    • Solutions containing chlorhexidine and cetylpyridinium chloride mostly found in mouth rinses and face wash can also stain teeth. 
    • Some other drugs that can cause teeth discoloration include Antihistamines, antipsychotic drugs and antihypertensive medications.
  • Materials used in Amalgam restoration –  Silver sulfide-containing amalgam restorations can cast your teeth to a gray-black colouration.
  • Aging: Advance ageing may erode the outer layer of the enamel on your teeth. Eroded enamel exposes the dentin below which is yellow in color. Also, ageing may reduce the translucency of the teeth making it look yellow or darker. 
  • Genetics: Tooth shades are genetically predetermined.  Some people have thinner enamel which makes their teeth appear more yellowish. While in some other people thicker and whiter enamel can be seen.
  • Environment: Too much fluoride from environmental sources like water or excessive use of fluoride application from toothpastes, and rinses can cause fluorosis, which look like white spots on teeth.
  • Trauma: The damage to tooth during early age (younger than 8) can disturb enamel formation in children 


4. What is the procedure for tooth whitening?

Tooth whitening process is not a recommended procedure for everyone. Individuals with yellow tones are found to respond best. Let’s find out whether teeth whitening procedure is fit for you or not and what does the procedure involve. A teeth whitening process starts with consulting your doctor first. If your doctor considers you an ideal candidate for tooth whitening process, then he may recommend you to undergo any of the following procedure:  

1. OTC Products 

Stain removal toothpastes contains mild abrasives that scrub the teeth and provide natural looking white teeth. You can also look for toothpastes which contains whitening agents and have earned the ADA Seal of Acceptance for stain removal. ADA sealed toothpastes, strips and bleaching agents are safe to use and provide effective stain removal with additional polishing agents.

2. In-Office Bleaching

In-Office bleaching is usually carried out at dentist’s office. During the procedure you will be allowed to sit on chair. The dentist will then apply a protective gel or a rubber shield to your gums in order to protect them against bleaching agents. After which, tooth cleaning/whitening agents will be applied to the teeth. and the peroxide will further be activated by applying heat or light. Different types of lights can be applied to activate the bleaching agent like halogen light, metal halide, Plasma arc lamp, and diode lasers.The in-office treatment usually takes around one hour to complete and can result in significant whitening just after one treatment.

3. At-Home Bleaching 

At-Home bleaching technique has several advantages. It offers self-administration by the patient, high degree of safety, low cost with fewer side effects. You can ask your dentist about how to whiten your teeth, regarding the instructions on how to place the bleaching solution, and for how much time.  Also, ask your dentist to provide you with a custom-made tray to be used for at-home whitening.  The success rate of at home-bleaching from dentist is dependent on diligence of use, as some patients forget to wear the trays every day leading to inconsistency and failure of desired results.

4. At-home or dentist-supervised night-guard bleaching

The treatment is carried out by an individual at home, but under the supervision of a dentist. The technique involves application of a low concentration of whitening agent to the teeth through a custom-fabricated mouth guard worn at night. The treatment usually lasts for at least 2 weeks. At-home or dentist-supervised night-guard bleaching technique is one of the most widely used technique and has been used for many decades. 

5. When do you need to see a dentist for tooth whitening?

Healthy teeth usually appear white in color. A number of factors however can influence the color of your teeth like the diet which you consume, dental hygiene, genetics and disease or medications which you are taking. Tooth discoloration is also a sign of bad health, tooth decay and erosion. Its recommended that an individual should visit their dentist at least twice a year to maintain good dental health. Some other factors where you need to consult your doctor for tooth whitening services include:

  • Discoloration of a single tooth, which may result due to a cavity or an injury to the inside of your tooth. 
  • Discoloration of  your teeth which doesn’t get better with tooth whitening agents will require a dentist visit
  • Deep staining of the teeth which may be due to a cavity or demineralization of enamel.

All these types of issues are need to be addressed by your dentist.  The sooner the issues are catered, the better the outcome will likely be.

Are There Any Side Effects from Teeth Whitening?

Tooth whiteners or bleaching agents are usually associated with tooth sensitivity. It happens when the bleaching agents in the whitener gets through the enamel and irritates the nerve of your tooth. Overuse of whiteners may cause damage to your enamel and gums. In such cases, be sure to talk to your dentist and follow your doctors advice.

6. Is it a permanent process or require regular treatment?

Teeth whitening procedures does not provide you with permanent teeth whitening solution. It requires regular treatment. A single tooth whitening procedure may last from a few months to up to 3 years. However, the effects may vary from person to person due to their eating habits. People who smoke or drink beverages like coke, coffee, tea and even red wine can stain the teeth fading away the natural luminosity of your teeth.


The increasing demand for tooth whitening agents has driven many manufacturers and researchers to develop bleaching products that can be used at home or in-dental offices. However, to minimize the chances of risks associated with tooth whitening like tooth sensitivity, the involvement of dental professionals are necessary. Limiting the use of OTC bleaching products and overuse of such products should also be considered.