Partly thanks to technologies developed by Renishaw, a Gloucestershire based company, cosmetic dentistry is no longer the preserve of the rich and famous.

Contrary to the popularly held belief, it’s reasonably certain that US president George Washington did not have false teeth made of wood. It is true, however, that by the time of his inauguration (at the great age of 57) he had just one of his own teeth left in his head. The several pairs of dentures he owned – each for use on different occasions – were in fact made of ivory, lead, steel and other various metals and included the odd cow and hippopotamus tooth for, one assumes, the sake of colour realism – rather than size match.

Washington couldn’t have known at the time how the nation he was instrumental in founding would come to lead the world in cosmetic dentistry. In parts of the US (mostly the part called California) preternaturally uniform teeth are a prerequisite for success. British actors arriving in Hollywood soon learn that teeth with more ‘character’ than their owners won’t help film careers. Reputedly, Ricky Gervais was rendered speechless when a tactless US film journalist complimented him on his willingness to wear false teeth for comic effect. To get on in the movie business you either have good teeth or comedic talent that renders your looks unimportant.

Mind you, the difference between teeth that live in North America and those that originate from the British Isles may soon be a thing of the past. Cosmetic dentistry has jumped the species barrier – and the Atlantic – and is no longer a mutation of the creatures that inhabit the hills north of Los Angeles. The cost of ‘intervention’ has dropped and technology has improved considerably which means that even Britain, previously considered by most Americans as the land that orthodontics forgot, has an emerging species with straighter smiles and improved self-esteem.

RenishawRenishawOrdinary people are prepared to overcome lifelong fears of the dentist’s chair and pay what most would consider large sums of cash to feel more comfortable when they open their mouths; and, why not? Aesthetic dentistry has benefited from the acceptance of cosmetic surgery in general (Bupa estimates more than 75,000 cosmetic procedures a year in Britain) meaning the public is more inclined to have treatment and is also more aware of what’s possible.

“People see cosmetic dentistry on the TV,” says Dr. Ewa Rozwadowska, owner of Confident Dental Care, a private practice based in Gloucestershire, “and it prompts them to do something about their own teeth. Maybe they’ve been living with a problem for years, or even decades. They don’t always realise how long a procedure can take and how much work it can sometimes involve, but the results can be amazing.”

Dr. Rozwadowska is an example of a new breed of dentist specialising in reconstructing people’s smiles. Rather un-typically, she and her team are also helping to push the boundaries of what’s possible, working to develop new technologies and procedures with the design engineers at the Dental Products Division of Renishaw, and technicians at the Implant and Ceramic Centre, in Miserden, a few miles down the road.

“It’s our aim to make the mouth as good as it can be,” she says, “and as good as the customer wants it to be. We work with award winning dental technician TJ Nicolas, owner of the Ceramic Centre. In fact, technician is a misnomer. He’s more of an artist. He makes every crown and bridge by hand, creating teeth that look extremely realistic. Most of our customers don’t want the white picket fence look.”

Nicolas and his small team work from what appears to be a cross between an atelier and a laboratory. On a bench at one end of the open-plan space sits a Renishaw inciseTM scanning machine, a technology that is changing the face of cosmetic dentistry and, quite literally, the faces of its proselytes.

The restoration process starts when the patient visits the dentist, firstly for a consultation then for initial work to create a temporary bridge or crown. At this early stage the dentist modifies each of the teeth ready to accept the prostheses, removing decayed areas of tooth and creating what are referred to as preparations. Once these preparations are finished, the dentist makes an impression of the patient’s upper and the lower jaws and sends them to the technician’s lab where they’re used to create a stone model. The technician segments the model and the individual preparations are scanned using the Renishaw incise machine. The rendered 3D computer models of the preparations are sent to Renishaw’s milling centre at Stonehouse, Gloucestershire, where the copings (the seats for the crowns) are machined from zirconia ceramic. The copings are sent back to the lab, where technicians build the outer tooth using fired porcelain.

“Most crowns being made and fitted these days are still modelled on a metal base,” says Dr. Rozwadowska. “But the problem with these crowns is that the metal isn’t bio-compatible, which means that the gums may recede rather than overgrow the tooth. People with metal crowns usually have an unsightly dark area on the gum above or below the tooth.” Zirconia is biocompatible; the same material used in hip joints, which means the patient’s gums grow close to and over the lower part of the implants, making them appear natural.

Dr. Rozwadowska and her team worked closely with Renishaw to develop the new process and the incise machine.

“Bryan Austin (Director General Manager, Renishaw Dental Products Division) came to see me and showed me the copings the company had developed. I offered to work with him to refine the process and he was very receptive to my ideas and observations. In fact, he arranged for the Renishaw board of directors, including Sir David McMurtry, Chairman and Chief Executive, to visit us here. They were very interested and asked a lot of questions.”

Refining the accuracy of the machined copings was one of the areas where Dr. Rozwadowska’s feedback was particularly valuable. It’s vital that if a crown is to be comfortable – and if it’s to last as long as possible – gaps between the tooth and the coping have to be eliminated, to prevent debris and saliva attacking the tooth and the gum. Renishaw has developed a process to machine zirconia in its soft state, before it’s fired and hardened. The machining is fast, easy and accurate, allowing cost-effective manufacture of multi-unit bridges.

“When we put a crown in the patient’s mouth it will fit perfectly. The precision is phenomenal!”

Dr. Rozwadowska’s readiness to work with Renishaw has already had considerable benefits for her business.

“The experience definitely made me up my game,” she says. “I had to think very carefully about what we were trying to do. I also had to learn to articulate the process so I could communicate with the design engineers. Not many dentists have the opportunity to work on breakthrough technology and techniques. I consider myself very fortunate.”

Some of Dr. Rozwadowska’s patients were also closely involved; none more so than Mrs. Pat Ind.

“Pat’s case was particularly complicated, both technically and also aesthetically. She had a bridge fitted 15 years ago. By the time she came to see us the metal under the crown was visible and when she smiled, her inner lip would catch on the bridge.”

Mrs Ind had a 5-unit bridge machined in zirconia by Renishaw.

“I felt very honoured,” she says. “Renishaw told me that it was one of the first units they produced using the new process and it still looks beautiful two years on.”

Renishaw has since fine-tuned its process, bringing the cost down from £Hollywood to £Stroud. Even so, a full mouth rebuild can still amount to more than £15,000.

“It wasn’t cheap but it was worth every penny,” says Mrs. Ind. “As we made progress I kept thinking to myself, this is brilliant. I couldn’t believe the transformation and I was amazed it only took six months!”

To paraphrase another US president, Benjamin Franklin, if ever you meet Pat Ind you’ll notice how she laughs readily at all of your jokes. And why shouldn’t she? She has very fine teeth indeed.

Source: Renishaw plc
New Mills
GL12 8JR