Tooth Whitening
Tooth whitening or tooth bleaching is the process of lightening the color of human teeth. Whitening is often desirable when teeth become yellowed over time for a number of reasons and can be achieved by changing the intrinsic or extrinsic color of the tooth enamel.[1] The chemical degradation of the chromogens within or on the tooth is termed as bleaching. Hydrogen peroxide is the active ingredient most commonly used in whitening products and is delivered as either hydrogen peroxide or carbamide peroxide.
Natural Shade[edit]
The perception of tooth color is multi-factorial. Reflection and absorption of light by the tooth can be influenced by a number of factors including the specular transmission of light through the tooth; specular reflection at the surface; diffuse light reflection at the surface; absorption and scattering of light within the dental tissues; enamel mineral content;[2] enamel thickness; dentine color, the human observer, the fatigue of the eye, the type of incident light, and the presence of extrinsic and intrinsic stains. Additionally, the perceived brightness of the tooth can change depending on the brightness and color of the background.
Indications[edit]
Tooth whitening may be undertaken for a variety of reasons, but whitening may also be recommended to some individuals by dental professionals.[3]
- Aesthetics
- Dental fluorosis
- Endodontic treatment
- Intrinsic tooth staining
- Tetracycline staining
Contraindications[edit]
Some groups are advised to carry out tooth whitening with caution as they may be at higher risk of adverse effects.[4]
- Acid erosion
- Sensitive gums
- Allergy to peroxide
- Pre-existing sensitive teeth
- Cracks or exposed dentine
- Enamel development defects
- Defective dental restorations
- Active periapical pathology
- Untreated periodontal disease
- Pregnant or lactating women
- Individuals with poor oral hygiene
- Patients with unrealistic expectations
Maintenance[edit]
Despite achieving the results of treatment, stains can return within an initial couple of months of treatment.[5] Various methods may be employed to prolong the treatment results, such as:
- Brush or flush out mouth with water after eating and drinking
- Floss to remove plaque and biofilms between the teeth
- Drink fluids that may cause staining through a straw
- Take special care during the first 2 days – the first 24–48 hours after the whitening procedure is seen as the most crucial period in which you must protect your teeth the most. Hence, it is vital that non-staining drinks or foods are eaten during this time as enamel is prone to adhere to stains.[6]
- Depending on the method used to whiten the teeth, re-treatment every six months or after a year may be required. If an individual is a smoker or they consume beverages with the capacity to stain, regular re-treatments would be required.
