Tooth whitening
There’s quite a lot of confusion about teeth whitening, and the differences between “laser bleaching”, take home kits, whitening strips, whitening toothpastes etc.
This short guide is to try and explain what exactly is involved in tooth whitening and how it works (and will it work for you?)

First of all why whiten teeth?
In my experience, tooth whitening is an excellent treatment and the first choice for improving my patients’ smiles. I recently had a patient consult with me to ask about getting 10 veneers to hide his very brown upper teeth (a very extensive treatment plan); but after I asked him to try teeth whitening first, he was so happy with the result that he no longer wanted the veneers.

Tooth whitening is:

*  Inexpensive
*  Conservative (non-destructive) – tooth enamel is not removed
*  Whitened teeth never look fake – real teeth still look real – just brighter and cleaner
*  No permanent side effects, although a TEMPORARY sensitivity during the process is common 🙁

Who is suitable?
Most adults are suitable for tooth whitening, but yellow/brown discolouration responds better than grey. If you have crowns, veneers or white fillings then they will NOT change colour and may look yellow beside your newly whitened teeth. Your dentist will be able to discuss this with you before your treatment.

But I have only one dark tooth!
Often, it is possible to bleach a tooth from the inside if it the only one that has discoloured (typically after a root canal). Again this is a very conservative treatment – you may not need that crown after all!

How does it work?
There are essentially two main types of long-term whitening:

  1. In surgery bleaching, where a high concentration of bleach is applied to the teeth by the dentist for a short time (1-2 hours). In my experience this bleaching is only effective when combined with the custom tray kits worn at night time (option 2 below), otherwise the results fade within a few weeks.
  2. Take home kits using custom made trays which fit exactly to the shape of your mouth and hold the whitening gel against your teeth for a longer exposure time (6-8 hours a night for 2 or more weeks). This is what I recommend for the majority of my patients.

So what about the kits you can buy over the internet or in the chemist?
There are a few things to consider here here:
*  Most importantly, the tray used to hold the bleach should be custom-made to your mouth and fit exactly; if it is not tight and allows the bleach to leak, then results will be poor.
*  The active ingredient used in our kits is 10-15% carbamide peroxide (equivalent to 3-5% hydrogen peroxide). Most whitening products bought over the counter such as toothpastes and whitening strips contain just 0.1% hydrogen peroxide.
*  Some unlicensed internet distributors supply bleaching products that are too acidic, which can permanently strip your enamel. You should always use a reputable professional when considering cosmetic dentistry – dental enamel NEVER grows back.

If you would like more information about tooth whitening, please call us on 01 4542022 or by email on, or for examples of what tooth whitening can do for you!


Patient: Brian aged 33 years was unhappy with the shape and colour of his teeth. After discussing various options including Orthodontics, we decided to do a course of tooth whitening followed by cosmetic bonding of his front teeth to change their shape.

Treatment: Tooth Whitening followed by Cosmetic Tooth Bonding.

Duration of treatment:  Slow-release whitening followed by one visit in the chair for Cosmetic Bonding.

Cost: €349 Whitening and €600 Cosmetic Bonding.

Treatment done by Dr. Helen Walsh.

No re-touching of photographs has been done.

Patient: Jeff, a good looking guy, aged 31 years was really embarrassed by his discoloured teeth–until he visited us at Portobello Dental Clinic–he confidence is now amazing, and he socialises regularly.

Treatment:  Slow release whitening

Duration of treatment: maximum 24 nights.

Treatment carried out by Dr Helen Walsh.

Cost : €349

All photos untouched

These photographs are untouched

Treatment : Tooth whitening and cosmetic composite of the upper right canine tooth. This treatment is very conservative; not tooth structure is removed and it is an entirely painless procedure with no need for anasthetic.

Treatment carried out by: Dr Nicholas Beirne

Treatment time: 3 visits over five weeks

Cost of treatment: €580

After :
These photographs are untouched

Treatment: Using the most advanced whitening system currently available, we can achieve never before seen results with little or no sensitivity. See here for more details about Deep Bleaching. In this case we whitened all the teeth and then built up the worn two front teeth using aesthetic composite

Treatment carried out by: Dr Nicholas Beirne

Treatment time: 3 visits over five weeks

Cost of treatment: €1,250

Before :

After :

Treatment: Cosmetic bonding and tooth whitening. This treatment is very conservative; we added to, but did not cut away any of Denise’s existing teeth. Because of the way this treatment is done there is no drilling, and no need for any injections or anasthetic, and the whole proocess is entirely painless. See Denise’s video here

Treatment carried out by : Dr Nicholas Beirne

Treatment time : 3 visits over five weeks

Cost of treatment: €850