Catherine thought she was being smart when she chose a clinic near Harley Street, the London address long synonymous with high-end private healthcare. She was in her early 30s and wanted to improve her smile. At least, looking back now – after all the pain, the nightmares and the legal fees – she thought she did.

“With hindsight, my teeth weren’t actually that bad,” Catherine (not her real name) says. “But they were quite gappy. I didn’t have the confidence to smile in photographs and used to talk with my hand over my mouth. And then I saw this voucher deal. That’s when I took the plunge.”

The offer was for veneers, a cosmetic treatment that is in soaring demand as part of a wider boom in cosmetic dentistry. They have become a shortcut to what used to be known as a Hollywood smile but could now be called the Love Island smile, such is the unnatural perfection of even non-celebrity teeth on reality TV and social media.

Veneers can be sculpted from resin or applied like false nails. For a cost that can be more than £1,000 a tooth, you can choose your shade of white, while increasing the surface area of the tooth to close gaps or create neatly aligned edges that would be the envy of an ancient Greek stonemason.

Veneers were indeed born in Hollywood, where dentists were recruited to, for example, fill the gap in Judy Garland’s front teeth or help with continuity when Shirley Temple’s baby teeth fell out. They used acrylic or denture powder to make these temporary fixes. By the 1980s solid veneers had been developed and the movie stars of the 90s redefined the perfect smile.

There are no statistics on the demand for veneers today, but dentists who dabble in cosmetic work say veneers have become as routine as Botox or lip filler for people with cash to burn who would once have tolerated or ignored crooked gnashers. For so long the butt of jokes for their charming disorder, British teeth are not what they used to be.

“There is a huge demand for veneers that is largely driven by social media and this desire for anatomically symmetrical white smiles,” says Anshu Sood, a co-owner of Helix House Orthodontics, a clinic in Nottingham.

Sood specialises in moving teeth, but has expanded what Helix House offers to meet rising demand for veneers as a follow-up to braces. She says patients want to transform more than just “the social six” – the upper front teeth most visible in a smile. “Now they want everything straightened, they want a wider smile,” she says.

Sam Jethwa, the founder of Bespoke Smile, a clinic and training academy in central London and Marlow, Buckinghamshire, has fitted more than 10,000 veneers in his time. “We now do around 80 new consultations a month, and place around 1,500 veneers a year,” he says.

Jethwa, who is also president-elect of the British Academy of Cosmetic Dentistry, says veneer consultations have quadrupled in the past four years. “We’re noticing increasing numbers of male patients,” he adds.

Costs vary according to the material used. Most in demand are porcelain veneers, which are half a millimetre thick and made in a lab. Fitting them generally requires what should be minimal preparation of the teeth, using a drill, before they are chemically bonded with a specialist glue. A cheaper alternative uses a composite resin, which can be applied as 3D-printed veneers or sculpted directly on the teeth.

Robbie Hughes, a dentist and the principal director of Dental Excellence UK, a clinic in Liverpool that has become popular with Premier League footballers (he’s responsible for ex-Liverpool manager Jürgen Klopp’s dazzling smile), says veneers for 20 teeth cost from about £7,000 using composites to £20,000 for porcelain veneers. His patients tend to be aged 20 to 40, and 40% are men.

Demand has increased for ever-whiter veneers as patients want to show off teeth that are obviously the result of expensive work. Sood says this has further skewed perception of what “perfect” teeth should look like. Hughes, who has noticed a recent trend for more natural shades, also did Roberto Firmino’s teeth. He says the Brazilian former Liverpool player pointed to a space beyond the whitest end of a porcelain colour chart and asked for “maximo”.

All the dentists I speak to say coronavirus boosted demand as home working induced a bout of self-scrutiny in mirrors and video calls. In a pattern that has applied to a whole range of cosmetic treatments, less talented or scrupulous practitioners have raced to meet the demand by competing on price and investing in social media marketing.

Catherine’s deal for several front teeth meant they were half the price she might otherwise have paid. She was impressed by the clinic’s equipment and decor. “And the dentist appeared to know what they were talking about,” she says. She went in for a consultation so that the veneers could be made, and returned to have them fitted over several hours.

The dentist set to work with a drill, but ground away far too much of Catherine’s teeth. “They showed me them in a mirror before the veneers went on and I looked like a witch,” she says. The dentist had left small pegs where Catherine’s healthy teeth had been. When the veeners were applied, her mouth wouldn’t close properly, so the dentist started to shave down her bottom teeth to make room.

“I was hysterical. I couldn’t stop crying,” recalls Catherine, who owns a small business in the south of England. “The treatment was so rough and I was so upset because I knew I’d made the biggest mistake of my life.”

When the painkillers wore off, Catherine says she couldn’t eat properly. Her veneers started to fall off, revealing the “witchy” pegs. Fearing that repairs elsewhere would cost her thousands more, she reluctantly returned to Harley Street to have the veneers refitted. Later, when one tooth split while Catherine was eating, she made an emergency visit to a local dentist.

“That’s when everything started unravelling. He was so shocked,” she says. The new dentist told her the wrong kind of glue had been used for the wrong veneers, and that her existing teeth had been horribly overprepared. “He said they were an absolute mess.”

He took pity on her and charged Catherine the same reduced price to have her veneers done properly. When the original dentist ignored Catherine’s demands for a refund, she contacted Russell Sutton, a solicitor who is in growing demand among the victims of botched cosmetic dentistry.

“It can be tempting for these dentists to take a few thousand pounds off young people and do a half-arsed job and leave them in the lurch, because it’s good quick money for them,” says Sutton, who set up TJL Solicitors in Manchester in 2000.

Christopher Dean, a dentist turned solicitor at the Dental Law Partnership, says the firm receives about five inquiries a week about badly fitted porcelain veneers, 30% more than last year. He describes a case in which a patient’s front teeth had been so overdrilled that the dentist had exposed the internal pulp chambers containing blood vessels and nerves.

Meanwhile, inquiries from unhappy customers to the General Dental Council (GDC), which regulates UK dentists and dental health professionals, doubled from just over 2,000 in 2018 to more than 4,000 in 2022.

Sutton took Catherine’s case but warns that legal routes to compensation are out of reach for many people. He and Dean operate on a no-win, no-fee basis, meaning they will only take cases they are confident they can win, and where the payout is likely to be significantly more than their fees, which can amount to £20,000. This also requires the dentist to have the proper insurance to cover a payout.

Lawyers in the UK won’t touch a patient who has suffered from bad treatment abroad, which is a growing problem for a whole range of cosmetic work. “Choose your jurisdiction carefully,” says Dean, whose firm routinely turns away regretful dental tourists.

Turkey in particular has emerged as a centre for cosmetic work. The briefest online search shows numerous deals for veneers costing as little as €100 (£83) a tooth, or packages including up to 20 teeth, as well as flights and hotels, for a few thousand pounds.

Some of the social media and reality TV stars who have fuelled the trend for “Turkey teeth” have talked about their regrets. Jack Fincham’s smile helped him to victory on Love Island in 2018. He had gone to Turkey six months earlier and was soon inundated on Instagram by fans asking him about his teeth.

Yet Fincham later admitted he had not done his research. The term “veneers” is often used to describe far more invasive crowns, which is what he had. To fit crowns – caps designed to fit over an entire tooth, typically when it is badly decayed or damaged – dentists must first reduce the teeth to pegs to make space. And, Dean says, even when a crown is done perfectly, there’s a risk that it will kill the tooth.

For every veneer horror story, there are no doubt several more patients who are delighted. “They look fantastic!” says Neil Fowler, who had his “social six” done at a Brighton clinic several years ago when he became conscious of his wonky teeth in business meetings. “I’m confident anyway but it definitely made me feel better to suddenly go from crooked, slightly yellow teeth to a Hollywood smile.”

Patients with problems typically visit their local NHS dentist. Dean says the NHS is obliged to carry out any emergency treatment to rescue dying teeth, for example (but not, say, to fit replacement porcelain veneers). The NHS says its dentists are feeling the effects of botched work in other countries. “This puts unplanned pressure on dental teams who are working hard to deliver essential care for patients within the NHS,” says Jason Wong, the chief dental officer for England.

Even perfect treatment locks patients into a lifelong cycle of costly replacements. At best, Hughes says, a good, well-maintained porcelain veneer (perfect hygiene, no chomping on toffees) can last 15 to 20 years. It can often be less, and as little as a few years before cheaper composites start to leak, crack or fall off. “I once accidentally swallowed one in a New York bakery,” Fowler says. “I don’t need to go into the details but let’s just say it’s back in my mouth now.”

Regardless of the material or lifespan, the damage that bonding does to enamel means there’s no going back to natural teeth once veneers have been fitted – something dentists tell me impressionable young patients don’t always consider. Returning to a less skilled dentist for replacements can compound the problem. “To get a good bond the second time round, they remove more tooth, and perhaps all of the enamel,” Dean says. “So then you’re into dentine, which is the inner core of the crown of the tooth, and you can’t glue to that as effectively.”

Dean says crowns are then often the only solution, with the risk of tooth failure and ultimately the need for implants (typically £2,000-3,000 each). “And these were healthy teeth to start off with,” he says, telling me he advises anyone wanting to improve their smile to consider bleaching and braces instead.

It took Catherine more than a year to get a payout from her first dentist’s insurer. She isn’t rich, but has the confidence to know she will be able to afford replacements when the time comes. She was also relieved to learn that, in an unrelated case, the dentist was struck off by the GDC.

But money and a sense of justice have done nothing to banish her memories of a botched treatment, or the knowledge that her teeth have been ruined. “I think I’ve got PTSD from it all,” she says. “Even now I won’t bite into food and have nightmares that my teeth are falling out. I feel really angry about the whole thing.” She says she enjoys her smile now, but tells friends and colleagues who are considering veneers to think twice. “I just say, leave them alone, because once they’re gone, they’re gone.”