As we become older, you might start to notice that you teeth start to become more yellow. You may feel self conscious and want to get rid of your yellow teeth, hence looking into many different ways to brighten or whiten your smile by getting rid of your yellow teeth. Teeth whitening are common cosmetic dental procedures with a large selection of methods such as home teeth whitening and laser teeth whitening via the popular Zoom teeth whitening system, making it highly accessible to the public.

Causes of yellow teeth and tooth discoloration

Before embarking on the journey to whiten your teeth, it is helpful to know what may be the causes behind your yellow teeth. With age, our teeth get worn out with function due to all the chewing and grinding that we put it through. This leads to the thinning of enamel, which is the hard protective layer of your teeth that gives it the white appearance. The wearing down of enamel causes it to lose its opacity and becomes more translucent. This allows the underlying dentine, which is yellow in color to show through, resulting to naturally yellow teeth. But this is not tooth staining per se, as it is a natural process. A way in which the wearing dentition can produce ‘true staining’ is when stains get incorporated into the fine crack or craze lines on our teeth, making it difficult to remove with conventional tooth brushing.

Types of Discoloration

There are two broad types of discoloration contributing to yellow teeth: extrinsic stains and intrinsic stains.

Extrinsic staining involves the outer surface of the tooth but does not actually involve the tooth structure itself. This is caused by the adherence of colored substances on tooth or plaque surfaces, and common sources include diet (betel nut/coffee/coke), tobacco or cigarette smoking and prolonged usage of certain mouth rinses. Such discolorations are usually relatively easy to manage with your regular oral dentifrices such as toothbrush and toothpaste. Tougher stains may require professional help and simple procedures such as dental prophylaxis, scale clean or micro abrasion can be carried out.

To know more about yellow teeth from smoking:

Intrinsic staining reflects structural changes within the tooth itself (enamel/dentine/pulp), where the composition or thickness of tooth structure has been altered. This can involve both the pre- and post- eruptive dentition.

Pre-eruptive changes are usually caused by disturbances occurring during the development of tooth/teeth and this also includes any prenatal influence, i.e changes during mother’s pregnancy. The discoloration on teeth varies depending on the causing agent but it usually has more severe effects, ranging from tolerable yellow shades to brown red colors. This is the main cause behind yellow teeth in children. The discolorations tend to be generalized, affects the same teeth bilaterally and has a symmetrical appearance.

• metabolic or systemic problems – alkaptonuria, amelogenesis imperfecta, congenital hyperbilirubinaemia
• drugs -  pre- or post natal tetracycline administration
• chemicals – excessive fluoride ingestion
• trauma – falling over, blow to facial regions

Post eruptive changes involve oral influences occurring after the tooth/teeth has erupted into the dentition. These tend to be less severe, again depending on the causing agent, and are generally localized. Contributing agents include:

• drugs – tetracycline, oral contraceptives
• chemicals – prolonged usage of chlorhexidine mouth rinse
• trauma – pulpal haemorrhage remnants, internal root resorption

Intrinsic stains are much harder to manage and commonly involve dental bleaching, dental porcelain veneers, or dental crowns/cappings.

You may also come across another type of stain, known as internalized discoloration. This refers to stains which have been incorporated into the tooth structure from an external substance, such as an amalgam filling or dental caries/decay.

Home remedies and Tips to Prevent Yellow Teeth

• Brush at least twice a day and also after meals to reduced retention time of colored substances on your teeth surfaces.
• Avoid food or drinks with a lot of colorings
• Eat fibrous food such as apple or celery to help clean teeth and remove stains
• Swish plain water around mouth after consuming food to dilute its effects
• Drink highly colored drinks with a straw to reduce its time in the mouth and contact with tooth surfaces