What Age Can You Safely Whiten Teeth? A Comprehensive Guide

03 July 2024

As the popularity of whiter, brighter teeth grows, more young adults are looking at cosmetic dental treatment to enhance their smile. Teeth whitening is one of the cheapest and most popular treatments young people are choosing to improve the appearance of their teeth. But how old do you have to be to get your teeth whitened and how safe is it? Read on for a comprehensive guide to cosmetic dentistry and teeth whitening for young adults.  

What Is Teeth Whitening?

Teeth Whitening is the process of lightening tooth enamel to give the appearance of whiter teeth without damaging or removing any of the tooth surface.

Just as our hair and skin colour differ, so too does the colour of our teeth. The natural colour of teeth is created by the reflection and scattering of light off the enamel which is the outer shell of the tooth.  Having smoother or rougher enamel affects the reflection and distribution of light giving the appearance of lighter/darker teeth. The thickness of enamel also plays a part as thinner enamel allows more of the dentine underneath to show through. Dentine is naturally much darker in colour so the more dentine that shows through, the darker the shade of tooth.

Teeth can discolour through stains caused by smoking or consuming highly pigmented food & drinks such as tea, coffee, red wine, cola and blackcurrant. This is called extrinsic stain. Not taking good care of your teeth will increase the likelihood of forming extrinsic stains. This type of discolouration typically responds well to teeth whitening. A combination of professional stain removal and teeth whitening is likely to achieve the best results.

It is also possible to have stains that are inside the tooth. The cause varies from some genetic disorders, issues arising during tooth development including trauma to the teeth, ageing and some antibiotic use. These stains are called intrinsic stains as they relate to the intrinsic colour of the tooth. This type of discolouration is less common and typically more difficult to treat. It requires professional intervention by a dentist or dental hygienist to improve the appearance.  

What’s Involved In Professional Teeth Whitening?

Professional teeth whitening procedures are carried out at your dentist. They can be done either in the dental office or at home and they use a tooth whitening gel that contains either hygdrogen peroxide or carbimide peroxide applied directly to the tooth surface.  

There are many different systems available to dentists and they will vary from country to country. Broadly speaking, whitening offered as an at-home treatment will involve the dentist making a custom-made tray that fits over your teeth. Whitening gel is placed inside the tray and worn for between 1 and 8 hours depending on the type & strength of the solution. The teeth gradually lighten over a period of 2 to 4 weeks and the results generally last from 6 months to around 2 years depending on lifestyle factors and standards of oral hygiene.  

Whitening that is performed in the dentist office usually uses a stronger solution that is applied to the teeth for between 15 and 30 minutes. A special light is used to speed up the chemical reaction and the process is repeated up to 4 times. This is sometimes done in the same visit or over a few consecutive appointments. If the teeth require significant shade change, your dentist may suggest that you continue the bleaching process at home for a few days afterwards.  

How Long Does Professional Teeth Whitening Last?

Teeth whitening isn’t a onetime procedure and the procedure will need repeating to maintain the lighter shade. If lifestyle factors that contributed to the discolouration continue such as smoking or frequently consuming tea & coffee, it is likely the staining will return quickly. If you follow the recommendations of your dentist, you can expect the whitening to last up to two years.

What Over-The-Counter Whitening Products Are Available?

There are currently no DIY methods that will produce the same results as professional whitening so manage expectations carefully.  

Whitening toothpaste can help remove some surface stains. They usually contain an abrasive agent varying from mild to harsh so choose carefully. Some also contain chemical agents but the effects aren’t usually dramatic and can take up to 6 weeks to see a difference.

Whitening strips that stick to your teeth or paint on gels, are quite readily available now.  Although these products contain a whitening agent, it is present in a weaker strength meaning the effects are limited and tend not to last very long. Always follow manufacturers instructions for the best results.  

Whitening mouthwashes are one of the least effective products you can use, largely because the agent is only in contact with the teeth for a very short period of time.

Products that use lasers or lights are not approved or recommended for unsupervised use.  

Is There A Teeth Whitening Age Recommendation?

Dental whitening is heavily regulated and can only be carried out by licensed dentists or their supervised dental auxiliaries. In most countries it is illegal to perform dental whitening on under 18’s. This is because the use of dental whitening products may cause damage if the enamel is not fully developed resulting in sensitivity and an uneven colour. For this reason, children must wait for 2 years after the eruption of the last adult permanent tooth to allow for full enamel calcification.

Severe discolouration of teeth can lead to low self-esteem and can impact on a child's day to day life if they encounter bullying as a result. There are exceptional cases where dental whitening can be performed on an under 18 if it is considered beneficial to a child’s physiological health. Speak to your dentist if you are worried that tooth discolouration is having a negative impact on your child’s mental health.

What Are The Side Effects To Teeth Whitening And Is It Safe?

Teeth whitening is ideal for most people and is unlikely to cause any lasting side effects. It is common for teeth to feel sensitive during and for a short while after whitening and some people also experience mild gum irritation. This is more prevalent with higher concentrations of the active ingredients but is considered transient and should resolve quickly after treatment.  

What Are The Alternatives To Teeth Whitening For Teenagers And Young Adults?

You may be tempted to try so called ‘natural’ whitening remedies including the use of fruits or vinegar. These methods are particularly harmful to teeth due their erosive and abrasive potential and there are no viable studies to support their use. Charcoal based products and toothpastes are commonly advertised as having natural stain removal properties but there is currently no evidence that they provide any benefit over regular toothpaste in whitening teeth.

The best way for teenagers and young adults to maintain a bright smile is through good oral hygiene and visiting their dentist and dental hygienist regularly. For children wanting cosmetic improvement who don’t meet the safe age requirement for dental whitening, GBT offers a way for stains, calculus and plaque to be removed in a pain free, chemical free, minimal invasive way. GBT promotes prevention as the cornerstone for a long term healthy, bright smile and encourages good habits from a young age.  

Always consult with a dental professional to discuss the best and safest options before deciding on any teeth whitening treatments.