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David Westgarth caught up with Dr Michael Norton, specialist in oral surgery, Norton Implants, at the DSWorld Conference in Dubai to discuss all things implants

How quickly are implant systems changing and evolving to meet the needs of the patient and practitioner?

MN It's an interesting question. It depends on your perspective. For many implant systems, things are developing very fast indeed, but from my perspective, having used an implant that was the first in the world to have micro-texturing and micro-threading with an internal conical joint, then you could argue that not much has changed in the last 30 years.

When we were developing the technology around the Astra Tech implant in the 1990s we were way ahead of our time - more so than we realised. This implant effectively introduced the world to the micro-threading and micro-texturing technology we use today, and it was a very unfamiliar territory for most. So, while some of the technology has moved on, from my perspective, they haven't actually changed that much.

What has changed in that time?

MN The two most impactful changes I have seen are the introduction of CAD/CAM abutment technology - that had a massive shift in the quality of restoration I could provide on the implants relative to stock abutments, and as a natural progression, more recently the use of intra-oral scanners and allowing us to impress our implants digitally.

Of course, oral scanners have been around for a long time, but not necessarily for implant dentistry, and indeed the technology wasn't always there. With Primescan, the technology is as good as - if not better - than an analogue impression - and can be used for multiple implants. It could be used to capture a full arch impression, if you so wish. The digital side of dentistry is what has helped to revolutionise my practise and the way I practise.

How has the integration with digital dentistry helped to increase the predictability - and resulting success - of implants?

MN Success is a relative term. I've run a solely implant-based practice for 30 years, and you can't do that if you're getting repeat failures - I wouldn't be in business today! I've always had good success at the implant level, but I think where success has been more challenging is at the aesthetic level. If we're talking about providing aesthetic restorations on implants, the whole digital workflow combined with advances in material science has really changed the outcomes for patients from an aesthetic point of view. From a functional and bone maintenance perspective, I work with an implant that prides itself on being a biologically designed implant. Most implant companies think of us like carpenters, but Dentsply Sirona has really driven hard on the need to respect bone. You have to go back to the 90s where Stig Hansson introduced a bio-mechanical concept to implant design, which led to the concepts of micro-texturing and micro-threading. Even if people don't use the Astra Tech implant, be under no illusions: implant systems today of all creeds and colours all have micro-texture and all have some form of micro-thread, and mostly have internal joints. There is a reason for that, and it all started with Dr Hansson's theories.

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© pAndriy Onufriyenko/Getty Images Plus

You mentioned your success with implants. How much emphasis do you put on the need for the right education and training, and the role mentors can play?

MN Education is absolutely fundamental. One of the things I try and point out to practitioners when they embark on implant dentistry is that it is an unusual symbiotic relationship between biology and engineering. Most of us have training in biology and we understand about bone, soft tissue, inflammation and so on and so forth, but no dentist receives training in engineering. They don't understand what a 'bending moment' is, or torque or pre-load - these are terms we borrow from engineering, but they're also central to the success of an implant restoration. As a result, I go out of my way to tell dentists that if they want to be good implant dentists, they have to learn about engineering. I would say to any undergraduate graduating now, go on a post-grad course, get a mentor and get your education, but make sure that incorporates an element of engineering, too.

This links in with the second part of your question about mentoring. I think that's only necessary because there isn't a robust pathway of education in the dental curriculum. Not even in America do they get a robust education in implants at undergrad level. The end result is it has essentially become a post-graduate specialty, which leads us to the question of whether implant dentistry should actually be a recognised speciality. I understand the issues surrounding that question and the difficulties the GDC would face with policing it, but I firmly believe in the idea that you shut the door before the horse has bolted, not after. Making implant dentistry a specialty would help to close that particular door.

Should this change? Should implants be taught on the curriculum?

MN Absolutely, yes, but probably only at a theoretical level. I think every undergraduate needs to graduate with a thorough understanding of the principles and concepts of implant dentistry. As a dental student at Cardiff Dental School, the Dean at the time was an orthodontist and did not believe orthodontics should be part of the undergraduate curriculum, other than in theory. As a result, I never did a single second of clinical orthodontics before graduating. Consequentially, I never did any orthodontics - rightly so, in my opinion - and if I wanted to, I'd have to learn that as a postgraduate.

However, we did learn the principles, and I thoroughly understood those principles. In the same vein, I believe all undergraduates should have thorough theoretical training and the requisite knowledge of implants so that they understand what they are, what their problems are and what the engineering principles are.

Having said that, I don't think it appears viable in today's world where students are struggling to meet their quotas for basic clinical dentistry to be able to expect the dental schools to ensure students complete an implant - that's not realistic, so we have to be pragmatic, which is why I believe they should all be taught the theory.

What do you find most challenging about the discussion surrounding peri-implantitis?

MN The biggest issue I have surrounding the discussion is the determination within some corners of the profession to make people believe this is some kind of epidemic that afflicts every implant ever placed in a human being. It is nothing like that. If you run a practice like mine placing hundreds of implants every year for 30 years, you gather enough data to be able to say yes, there is a small problem, but it probably runs between five and 10%, which meets what some of the literature out there on peri-implantitis expects. The problem with the literature is how you define peri-implantitis will determine the prevalence. If every implant you probe bleeds and this is classed as peri-implantitis, then expect 100% of implants to have it! You need to ask yourself whether that's realistic. There are many different aetiologies that can lead to peri-implantitis, and they don't all respond the same way to treatment. It's not solely about the management of biofilm, and every case has to be judged on an individual basis.

Together with my colleagues at the University of Pennsylvania I was involved in a study which showed there are multi-factorial aetiologies giving rise to peri-implantitis. It is a problem, and a manageable one at that. It is not an epidemic, and certainly not as much of an issue as some would like to have us believe.

Mucositis is different. This does afflict more implants, which begs the question 'doesn't mucositis always lead to peri-implantitis?' I would have to say throughout my career and resulting experience, no it does not. You can have mucositis around one implant but maintain bone at the top of the implant for years. I don't believe we fully understand the transition between one and the other, but mucositis can be managed with careful prophylaxis.

Finally, how do you see the future of implant dentistry in the UK taking shape?

MN It is ostensibly a healthy, positive one. It is being shaped by the profession in the absence of the regulator shaping it for us. The problem with that is it then opens the door to being abused by people who are not robustly educated or capable of performing implant dentistry. Everyone needs to know their limitations. I haven't done a root canal treatment since dental school because frankly I was rubbish at them. If a patient of mine needs one, I refer it and would expect the same professional courtesy with implants. Most of my referring dentists do understand and recognise their limitations and don't want to do the surgery. That's where the problem lies, but if you could set it aside, I bring a message of hope - we're on a good par with the rest of the world. There will always be professionals who spoil the reputation of their profession, but that's true whether you're an accountant or a lawyer - there will always be those who do not choose to educate themselves and who do not recognise their limitations.

You also need to consider that the future of dentistry is entirely digital. for those who have spent their entire careers in an analogue world - like me - that can be a scary prospect. I didn't adopt the whole digital pathway in one go. Companies like Dentsply Sirona are fundamental to that digital development, providing a total paradigm shift in what is truly capable with the right software and the right technologies. I use DS Core - their cloud-based software - which has the potential to provide me with an entire digital workflow at my fingertips, and all it does is confirm to me that the days of analogue dentistry are well and truly over. People who don't seriously start to adopt digital dentistry are going to get left behind - it's an inevitability. â—†