Whether you're coveting the classic Hollywood smile, or the Love Island look, getting whiter teeth requires some commitment. While the high street is stocking more and more quick-fix whitening kits, the most effective – and safest – option remains the professional route; an in-clinic laser treatment and use of a dental grade gel at home.

These are the options offered by celebrity dentist Dr Richard Marques of Wimpole Street Dental, who spoke to Bazaar about the process, including any potential side effects and how to make the results lasts. Read on for all you need to know about getting (and keeping) whiter teeth.

There is a big difference between professional and at-home teeth whitening, but the best results combine the two...

“Laser teeth whitening in-clinic really just treats the surface of the teeth, so this will give great results but they will not last. Home whitening with the dental grade gel and trays alone will whiten the inside of the teeth, but not so much the surface. Therefore, when using a combination of professional laser in clinic whitening with top-up trays you are able to whiten both the inside of the tooth and the tooth surface. This gives amazing, long-lasting results that are much more evenly spread along each tooth.

“Home whitening kits from the chemist (for example), or bought online will not work in the same way and the use of whitening strips can damage the teeth or risk ingestion of peroxides or other chemicals.”

Everybody’s teeth respond differently to whitening treatments

“This is due to the thickness of your enamel. Teeth whitening only really whitens enamel (it will not whiten the roots of the teeth) and teeth with enamel wear will take more time to whiten. Also, fillings, crowns, bridges and implants will not whiten. These may need to be changed after the teeth whitening process to match the new shade (colour) of the teeth.”

The time it takes depends on the look you want

“Laser teeth whitening can be done in a one hour appointment (with a minimum of three days with the top-up tray at home, for 30 minutes a day). Some patients use the trays for seven days or even up to 14 if they want the teeth really white.”

Many clients ask me for the ‘Chelsea smile’

“The ‘Chelsea smile’ describes a trend for teeth whitening made popular by this area in West London and those who live there (and watch shows like Made In Chelsea). This is a much more natural colour for the teeth that is still white but keeps the character of the teeth and goes with the chic image of many Chelsea girls/guys.

“I find Americans tend to like their teeth far whiter (especially is they are from LA due to the Hollywood influence). However, I also find some patients want a super white glow (as made popular by shows like The Only Way Is Essex and Love Island).”

Be careful not to over-do it, unless you want that obviously whitened look

“We often provide a home shade guide so that you can measure and monitor the teeth whitening to see how you are progressing. Also your friends and family can help to advise you. Alternatively, you can send us photos by e-mail, text or WhatsApp and we can match your shade with our in-clinic shade guide.”

"Whilst whitening, eat a whiter food diet, as this is when the pores of the teeth are most open"

You’ll have to avoid pigmented food throughout the treatment

“Whilst whitening the teeth (and for 48 hours after) you should eat a whiter food diet as this is when the pores of the teeth are most open. Options include chicken, rice and fish and if you are vegetarian chickpeas, cauliflower and celery are great options. You can also eat beige food such as bread, pasta and potatoes. Smoothies or juices should be drunk through a straw. White wine or clear spirits are acceptable and milky tea and coffee can be drunk, but avoid red wine and smoking, and takeaways with heavy artificial food colourings during this period.

“Once the in-clinic and home whitening is competed you can return to a normal diet (but smoking should still be avoided and see your dentist at least six monthly for regular check-ups and cleaning).”

When doing the treatment, you may experience side-effects

“Sensitivity of the teeth is possible but this is always temporary, so will fade. A sensitive toothpaste (such as Sensodyne or Colgate Pro-Sensitive) will help reduce sensitivity during the process.

“Some whitening or soreness of the gums can also be experienced during the process but this is normal and nothing to be concerned about as it will always subside.

“During the at-home process, it is important not to put too much gel in the trays and to wipe and excess away from the gums as it will irritate them if not removed. Warm salt water mouth rinses are recommended for soreness of the gums. Use a teaspoon of salt in a cup of warm water three to four times daily.”

We recommend you use professional toothpaste

“Another great toothpaste is from my range RM by Dr Richard Marques, an all-natural ingredient whitening toothpaste with sensitivity protection that is available in peppermint and strawberry flavours. Both are really great and will prolong and enhance the teeth whitening (and reduce any sensitivity).”

The results can last up to five years

“For the longest-lasting results, try to eat a whiter diet in general and drink staining fluids through a straw as a matter of course as this will bypass the teeth.

“Make sure you see your dentist and hygienist for six monthly check-ups and cleaning. Some people go every three months if they drink a lot of red wine for example.

“Your dentist can advise you on doing teeth whitening top-ups using your trays at any time (as they will still fit), and can sell you more professional gel.”

If you’re not happy with your results, you should…

“Let your dentist know. They may be able to provide some alternative whitening gel (from a different brand) which may work better for your teeth.

“You can also consider veneers if you have extremely dark teeth or enamel wear and there are new treatments such as DMG icon available for white patches of the teeth.

“Overall, professional teeth whitening is a great treatment and 95% of patients leave extremely happy with the results and think it is one of the best investments in their smile available.”