I sit back nervously in the dentist’s chair. “My teeth are pretty sensitive,” I mutter. The cold gel hits my enamel and I gasp. Suddenly, I regret letting my narcissism get the better of me. Again.

The cliché about Brits is that we have terrible teeth. But the Hollywood smile once reserved for celebrities, now sparkles from every screen. The desire for a blinding smile has spawned a dazzling industry in teeth whitening, from at-home kits, trays, pens, serums and stick-on strips to celebrity Harley Street dentists charging thousands. The market research company Mintel values the UK cosmetic dentistry industry at £2bn, and another recent report found that, on average, British men and women spend 11% more a month on their teeth than their skincare.