Dr Grant Duncan champions Invisalign

Dr Grant Duncan Invisalign
Dr Grant Duncan is one of the biggest Invisalign users in the world.

A very early adopter of Invisalign, Dr Grant Duncan of The Straight Smile Centre in Adelaide is always on the lookout for cutting-edge technology. By Kerryn Ramsey

In 2000, Dr Grant Duncan became one of the very first—if not the first—orthodontists to use Invisalign in Australia. He had been in San Francisco where he met the founders of Invisalign, Kelsey Wirth and Zia Chishti. At that time the technology was still in its early stages but Dr Duncan was intrigued.

“I came back to Australia and became a remote mail-in type of orthodontist,” he recalls. “I sent my impressions through the post and even though Invisalign didn’t have any international capabilities, we muddled our way through.”

Over the next few years, Dr Duncan came to the realisation that Invisalign didn’t work very well and wasn’t a very good orthodontic appliance. Then at a dental conference in Las Vegas, he met with other Invisalign users and saw that he had been going about things in the wrong way.

 “I realised I was blaming Invisalign because I wasn’t getting good treatment outcomes,” says Dr Duncan. “At the conference I saw that some beautiful work was being done. I was blaming the tool and not myself. My problem was that I was thinking like a braces orthodontist.”

Braces are a three-dimensional appliance that can grab a tooth and move it freely in all directions. With Invisalign, all it can do is push—and it has to have something to push on.

“I had to go back and apply biomechanical principles to this new plastic appliance,” says Dr Duncan of The Straight Smile Centre in Adelaide. “It turns out that while I was doing that, there were people in America and a few other early adopters around the world doing the same sort of thing. We would go to meetings, transfer information and the appliance got better and better.”

Dr Duncan appointed a key staff member in his practice to help him reach a goal of starting 300 Invisalign treatments a year within three years. In the process he became one of the biggest Invisalign users in the world. At the end of the three-year period, they totalled the amount of cases started in the preceeding 12 months and it clocked in at 300—exactly. From this experience, Dr Duncan developed a consultancy program for running a successful Invisalign orthodontic practice, and from this The Invisible Orthodontist community was born. 

Schopenhauer’s Three Stages of Truth

The 19th-century German philosopher, Arthur Schopenhauer, stated that: “All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as self-evident.” Dr Duncan feels he experienced exactly that as he attempted to introduce Invisalign to the wider dental community.

“When I made it known that I was going to treat most of my orthodontic cases with some newfangled plastic, there was an array of reactions from my peers,” recalls Dr Duncan. “But, in general, those reactions were at Schopenhauer’s stage 1 or 2, ridicule or violent opposition. In some ways it was fun to watch, as I understood the process within which I found myself. 

“When I made it known that I was going to treat most of my orthodontic cases with some newfangled plastic, sleepy old Adelaide seemed to explode.”

Dr Grant Duncan, The Straight Smile Centre

“The fun part was also over the years watching orthodontists enter the ‘evident truth’ phase.”

The way forward

Today, Dr Duncan is treating about 80 per cent of his orthodontic cases with Invisalign. He knows of other orthodontists who manage 100 per cent of their case load with Invisalign. “Many dentists believe that Invisalign is great for minor corrections but you need to use braces if you really want to move teeth,” says Dr Duncan. “That is totally wrong. Most orthodontic corrections can be achieved with Invisalign and in some cases, Invisalign is a better appliance. And that’s not accounting for the many health benefits around not using braces.”

While the Australian Society of Orthodontists (ASO) agrees with Dr Duncan to some degree, they still see a place for metal braces in orthodontics. Dr Theresia Sudjalim, the chair of the Australian Society of Orthodontists Communications and Information Committee, says, “There has definitely been great advancements with clear aligners, particularly in the past decade. However, the idea that clear aligners are a panacea that can do everything traditional braces can do is definitely not true. 

Dr Grant Duncan Invisalign
Dr Grant Duncan and son, Nick, run The Invisible Orthodontist, the largest network of specialist orthodontists in Australia.

“Clear aligners are really good at pushing. However, braces are better at holding onto individual teeth. Braces may be required to treat conditions like impacted or severely rotated teeth, but it is fair to say that clear aligners can treat more conditions now than they could 10 years ago.”

The negative impact of metal braces

There are many reasons why a patient would choose Invisalign over traditional metal braces. In fact, Invisalign has opened up a whole new market segment to orthodontic care—people who knew they had crooked teeth and needed braces, but who simply refused to wear them, often for aesthetic reasons. But Dr Duncan sees a number of physiological reasons to reject braces.

“Even if the patient brushes their teeth, braces can still cause decalcification marks,” says Dr Duncan. “This is a permanent loss of enamel tooth structure, leaving unsightly marks. If it gets away from the patient or the orthodontist, it can lead to active decay. Braces can also contribute to conditions such as root resorption or the loss of tooth vitality. So, between hygiene issues, gum infection, decalcification, decay, root resorption and tooth vitality, metal braces have a lot of negatives.”

Hygiene is definitely much easier to maintain with Invisalign as you simply take out the aligners and brush your teeth as normal. Dr Duncan claims that most of the negatives attributed to metal braces don’t happen with Invisalign because the teeth are moving in tiny intervals—as little as 0.1 mm per aligner.

“Anecdotally, many orthodontists believe root resorption and loss of tooth vitality is much less common with Invisalign,” says Dr Duncan.” But we still need the science to support that conclusion.”

Once again, the ASO is slightly at odds with Dr Duncan. “If you have a patient who is prone to root resorption, then any type of tooth movement can cause a problem,” says Dr Sudjalim. “Some people say that alignment therapy is more gentle because there’s less force applied but you need to look at biologic individual variation. This will affect the outcome regardless of the type of treatment.

“The idea that clear aligners are a panacea that can do everything traditional braces can do is definitely not true.” 

Dr Theresia Sudjalim, chair, Australian Society of Orthodontists Communications and Information Committee

“If you’re treating a person with bad oral hygiene, it’s certainly easier to brush with clear aligners as you are able to brush your teeth without appliances in place. But if the patient isn’t brushing their teeth effectively and generally has poor oral hygiene, then food particles and plaque can accumulate with the aligners in place and the patient is also prone to developing holes in their teeth and gum disease.”

Dr Sudjalim believes there will always be a place for metal braces and clear aligners in orthodontics. “The important thing is knowing what each appliance can do and choosing the appropriate appliance to correct the specific problem. Sometimes a hybrid is required. Sometimes you use both.”

The Invisible Orthodontist

In 2010, Dr Duncan and his son, Nick, started The Invisible Orthodontist (TIO). It began as an online consulting organisation but has grown to become the biggest group of Invisalign submitters in the world. The Invisible Orthodontist assists orthodontists in growing their orthodontic practices by helping them to establish themselves as the Invisalign experts within their communities. 

“We started with 10 people signing up,” says Dr Duncan. “Now there are 50 different TIOs in Australia and New Zealand. Five years ago, Align Technology started taking notice and encouraged us to emulate our Australian TIO experience in the UK. When Dr Duncan and his son started TIO UK, there was resistance, with many people claiming that because of the National Health System, people wouldn’t pay for dentistry or orthodontics. 

“We helped many NHS orthodontists, who were paid little by international standards, and who had little clinical control, into private orthodontics,” says Dr Duncan. “The end result is the UK TIO business is now bigger than the Australian version. It’s incredibly successful.”

The future

As an early adopter, Dr Duncan is always on the lookout for cutting-edge technology with potential. He sees great promise in a company called Dental Monitoring (DM). It provides artificial intelligence (AI) via a smartphone application. A patient uses the app by taking a video of their teeth every five days during their Invisalign treatment.

“The AI analyses all the data and tells the patient whether they can go onto the next aligner or not,” says Dr Duncan. “It also tells them if they’re wearing their aligners frequently enough; if they have hygiene problems; if there are any problems with a particular tooth; if they have gum infections or if they have gum recession.” A 2019 addition in the AI space will be SmileMate (SM), a startup headed by Nick Duncan. SM has the potential to revolutionise orthodontics, bringing dentist and orthodontists together in the orthodontic management of their patients, and giving consumers direct access to specialist orthodontic care. 

“DM and SM are very exciting and promising technologies. These are very exciting times.” 

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