The Reality of Broken Bites: Why Composite Beats Crowns for Worn Teeth

Dr. Melissa Seibert: Welcome to Dental Digest. This is a podcast with the mission of enabling you to stay on the cutting edge of evidence-based dentistry. I'm your host, Dr. Melissa Seibert. Dr. Didier Dietschi is back, and this is part two of a two-part series. As a reminder, if you missed the first part episode, Dr. Dietschi is one of the most respected researchers and clinicians in adhesive and aesthetic dentistry. He holds both a dental degree and a PhD, along with a private docent degree from the University of Geneva, where he serves as a senior lecturer. He's also an adjunct professor at Case Western Reserve University and has authored over 115 scientific publications and textbook chapters.

In this episode, we're going to move from philosophy into clinical execution and decision-making. Dr. Dietschi breaks down how to stratify wear cases based on severity, risk factors, and patient compliance, and how to build a truly individualized treatment plan. We get into the biomechanics of composite versus ceramics, why composite can often be the most biologically favorable material, and how to sequence treatment in a way that preserves tooth structure while still delivering functional and aesthetic outcomes. We also discuss real-world challenges like night guard compliance, failure patterns in restorative materials, and how to communicate responsibly with patients.

Dr. Seibert: So let me ask you this — and by the way, I have to thank you, because so many of us dentists, our dentistry will begin to age and it'll begin to fail, and we feel responsible for it. So we do these extensive restorations, the patient's not wearing a hard night guard, the patient refuses a hard night guard, and then the restoration chips, and it eats away at us. Just the other day I did a really nice composite restoration on a wear patient. She declined a hard night guard, and she's already back because the restoration slightly chipped, and it can really lead you to feel like a failure. You mentioned repairing the restorations, especially for patients that don't wear hard night guards. Do you require the patient to pay for the repairs? Who's paying for this?

Dr. Dietschi: The big problem — because I thought initially, even though I knew the reason for the chipping, I just thought, okay, for the first year or the second year, I have a kind gesture, I'm going to do it for free. It's usually not a very long procedure. And I realized it is completely wrong. Because in fact, we made a deal with the patient. Now when the patient refuses the night guard, I talk very openly about this. It became very natural to express this issue — to say: "Look, the night guard, you wear it every night, it's 100% protection against parafunctional activities, which we know are those that create the highest stresses on your restorations. During the day, even awake parafunction or clenching can still generate quite some strong forces, but proprioceptive feedback is active, so there is a certain sensation. The highest forces are recorded during sleep parafunction."

I'm telling them: the amount of stress that you might exert on the restorations — the same stress that created that damage to your natural teeth — might exceed the mechanical strength of your restorations. So I can do a full occlusal buildup to protect your teeth from further degradation for a relatively reasonable amount. If I do it with ceramics, I need to cut a little bit of your tooth structure, because if we want to be silica, I've seen lithium disilicate restorations — if you go with super-thin restorations in a heavy clencher, I can tell you it will break them if they don't wear the night guard. Not 100%. We are never in a binary — it's true that we tend to think as a binary situation, failure or success, but very often we are somewhere in between. But if you go with thin overlays in heavy clenchers, I can tell you that we can very easily fail if they don't wear the night guard.

And then it's getting a lot more difficult to negotiate, because you told them that this is a super strong material, and that is basically explaining why it's more expensive — it's done in the lab — and patients expect those restorations never to fail. I am really, really very clear to say: mechanical failures will be the result of non-compliance. Yes, I can do a crown of two and a half millimeters in classical zirconia, white like the tiles of my bathroom, and eventually you might not break it. But it will generate some wear on the antagonist, which is one of my issues with glass ceramics: at the moment the patient doesn't wear a night guard, e.max against natural teeth wears off the natural teeth quite a bit. e.max against e.max — you see the surface really suffering. If we have composite, that's probably a nicer couple, because it's less competitive, less prone to damage the glaze surface of our e.max restorations. The best couple is, let's say, glass-ceramic against glass-ceramic. That's probably the best couple.

But I'm telling them that there is no miracle solution without control of those factors, and especially mechanical fractures come from lack of compliance. I cannot damage your teeth to a certain excess, because if I prep thick enough, we take biological risks — it's very invasive. When you have a problem with your foot, I'm not going to cut your foot or your hand if you have an infection on one finger. It's unethical. I cannot do this. So to say: if you want to be treated by me, you need to assume. I say it nearly as I'm speaking to you right now. You need to understand that mechanical failures with non-compliance with the night guard — or if you don't want the night guard — that's on you. Because even if I use the best technique that the profession knows, evidence-based, the best protocol, it still has potential to fail unless I nearly destroy your teeth. We as healthcare professionals — this is not what we are supposed to do.

I personally prefer to face the patient with his own decisions that he needs to assume. And at the end, he's not happy. But I have many patients' cases where they think the night guard is not needed — they are not convinced. We don't find the first time a way to convince them. And now I have quite a number of patients who went through that situation. When they continue to break their restorations, one day it clicks somewhere. I'm always saying that it's also something with hygiene that you might observe. You do a treatment of a certain importance — you see sometimes a real increase in the motivation of the patient for oral hygiene. I think this is the invoice effect, but it's not lasting forever. When they start to forget about what they paid for their treatment, all of a sudden the motivation goes down. And when we get chipping or fractures or failures, if they need to pay again for the retreatment, that will bring them to realize that at certain moment they are forced to understand — either the financial impact is so little for them that they don't care, or they might care about having to come back to your practice.

But I'm telling them also very clearly that I will not accept to go with extremely invasive restoration. Because I've seen already some failures. You might go — depending on the amount of wear, if you prep a lot — then you might again be in conflict with the biology of the tooth. I don't want to undergo loss of vitality; then you need to do an endodontic procedure. And a non-vital tooth is always at higher risk for mechanical failures down the road. So it's not really the path I want to bring the patients on.

Dr. Seibert: I'm curious as well — you're Didier Dietschi. You are really one of the premier authorities in the world on composite, and doing these composite restorations requires a great deal of artisanship. So why do you charge a fraction of what you would charge with ceramic for your composite restorations?

Dr. Dietschi: Yeah, if you touch the business side, you have reached the wrong person. I'm from probably a different age. I have really looked at my profession as a hobby. I'm passionate about what I'm doing. I never looked so much at the rentability or income. Having said that — you know Newton Fahl. Did you have Newton Fahl for one of your interviews?

Dr. Seibert: I would love to have him on. We've had a hard time finding our schedules to connect. I should actually reach back out to him.

Dr. Dietschi: I hope you will. He's incredible. He's an amazing person, an amazing clinician, an amazing teacher, and also an amazing human being. He always told me that I was wrong, that I should charge nearly the same as an indirect restoration. But especially in the wear domain, I know the limits of the material. Sometimes I'm pushing a little bit the patient toward that direction because I believe this is the first thing to do.

If I just refer to a classical wear case — if I have some class one, class two decays or restorations to replace, that would be the normal first treatment. Okay, I'm going to restore all those or replace all those restorations, treat those decays in the first session, maintaining the VDO. To do everything occasionally I do it, but it creates very, very long sessions. If I redo all the class one and two in the same sessions, integrating the increased VDO — because normally we like to do one arch at a time in one day, left and right in the same day — so I prefer to do, at the rhythm the patient can accept and tolerate, replace the class one and two, everything direct.

If I have indirect, I will prep only the teeth which require an indirect restoration. That will set up the new VDO. It's done together with the wax-up according to a functional analysis and the new VDO that we have decided. And then I go with the direct restorations. But when it comes to the change, I will work 10 to 15 minutes per premolar, and most of the time I need to rebuild the cusps of the premolars. There isn't so much to do. Even if I need to build up the entire anatomy, 15 minutes is enough because it's going to be most of the time a single layer, and maybe 20 minutes for the molars.

Even if I charge, on average, around $400 per restoration, I do everything in an hour and a half, even a little more. I feel that it's a very decent income for doing something that I love to do. Because I must also say that when I have a case and I do a freehand buildup, it's not always complete freehand. I was just treatment planning one case before we started our meeting, and I have a couple of indirect restorations, and wherever I can I go direct. It's such a lovely work to do. And of course, this we need to learn.

Swiss are not having the genes of Italians. I thought that my name, Dietschi, would sound like Italian, but in fact it's northern German. It's coming from my family — comes from northern Germany, many generations before. Not having a famous ancestor painter or sculptor, I had to learn — but just repeating the same movements, and we improve by practice. I didn't feel, if I'm very objective, that I needed special talent. I think it was more conceptual — I was able to visualize and observe anatomy. It is true that I've done a lot of wax work, classical wax work, when I was a dentist because I love to do it. Since I spent really the first 20 years of my life mostly in the academic environment, I didn't have access necessarily to a big lab for doing this preparation work, so it was good for me to learn anatomy and do some wax-ups.

But we have also molding techniques — that you might have already seen in the book — that with a nice, good wax-up (and now with digital dentistry, we can fabricate easily beautiful wax-ups), we just need to make the surface smooth, either to seal the surface or polish the surface to avoid the print lines showing on the molded restorations. We have a lot of alternatives that will provide the same result, even maybe a little quicker. So for those who like freehand, they can do freehand. It doesn't need to be super sophisticated. But it is true that the freehand approach requires good control of the thickness. With the molding approach, you control the respective thickness from the back teeth to the front teeth. It's easier, and if you follow the protocol precisely, it's a great tool.

Dr. Seibert: Another question coming from your book. In your book, you emphasize multifactorial diagnosis for tooth wear — erosion, mechanical, and functional pathways, which we've talked a little bit about already. How do you structure your diagnostic decision tree in cases where patients present with overlapping etiologies, and what do you consider the tipping point that determines whether active restorative intervention is necessary? Because I think many dentists in North America — it's always difficult to decide when do we actually intervene and treat?

Dr. Dietschi: You mean increasing the VDO?

Dr. Seibert: Correct. And really even embarking on the quote-unquote full-mouth rehabilitation. We've already talked about how it's far more nuanced than that — it's far more customized to the patient. But when do you make that decision that it's actually time to do the restorative dentistry and intervene?

Dr. Dietschi: Oftentimes in North America, dentists will do the same copy-paste full-mouth rehabilitation. They will have a patient that comes in with some wear, determine that wear is caused by a deficit of ceramic, and then the patient gets a full-mouth rehabilitation. The better question to ask is: at what point do the symptoms and the presentation become bad enough that it's time to intervene? The smile damage that is created by tooth wear is clearly the element that brings the majority of patients to consult. So they have an aesthetic concern. The reality is that we can't address that problem in the majority of cases without doing something else. We need to create most of the time the space to restore the worn teeth.

So that is probably a critical element that brings us to tell the patient, "Look, we understand your request and your expectations, but in order to answer your needs and expectations, we will need to do a little bit more than just restoring the worn teeth." But sometimes it can be done. If we consider one example — take a deep-bite case, a class 2 division 2 case in a bruxer versus a clencher. The clencher — it is mainly clenching. It's true that it's very rarely only clenching, but you might have damage on the back teeth, very little on the front teeth. If it's really mainly a bruxer, as soon as the patient is moving — this is what John Kois calls "constrictive chewing pattern" — as soon as the patient is moving, you will disclude the posterior dentition and there is nearly no wear back there. So you might have severe wear in the front, nearly nothing in the back. But still sometimes, since you also have buccal wear on the lower and palatal wear on the upper, this needs to be taken care of.

The only way to take care of this is to increase the VDO, but it might be just a little cusp buildup on the lower. We can never augment so much because otherwise we not only open the vertical dimension, but as we all know, we also create sagittal discrepancy. So there are anatomical limits — but if we just open up a little bit, it's very easy to generate a little space and start building up the front teeth. So occasionally we might have very simple answers to this kind of problem.

Aesthetics is definitely the number one element that might bring the patient to engage in treatment. Less frequent is dentin hypersensitivity to cold and to acids — so patients are disturbed regularly or when brushing, and it might become sensitive. They look in their mouth and see something's going on. This is the second reason. Functional problems happen mainly in TMD cases — but otherwise, if we exclude TMD or TMJ pathology, true functional problems come when we lose posterior support, when patients start to lose posterior teeth. Then we might have a true collapse of the VDO, but those are relatively rare cases, especially in today's world. So I will make pictures, show the patient, try to evaluate the biomechanical impact of wear on the teeth, trying to somehow figure out what will be the situation of those teeth if we don't arrest the progression of tooth wear.

And of course that comes together with the age of the patient, the known risk factors, compliance of the patient. So this is really those three factors: risk factor identification through observation of the type of lesions, severity of wear area by area, age of the patient, and compliance. And of course we have different degrees. We compute a sort of — it's done through HI analysis, human intelligence analysis — to say, okay, if I balance now, if I try to bring those elements together, that will help me to define if we need to take action or if we just observe. There is always this interception of tooth wear that can happen through only preventive means — trying to provide diet advice or refer the patient to relevant medical specialists. Occasionally — and not so rarely — we start by checking if we can help the patient to control the risk factors. Together with the patient, we can see if we are on a good path or not.

I've seen a few patients — limit patients — who didn't do treatment, because the only option for them was full-mouth rehab. We could have done something simpler. They do nothing for 10 years, and when they come back, it's an absolute disaster. We have one of those cases in chapter two or chapter three of the book. The lack of action can be an absolute disaster. So severe wear normally requires at least interception early enough. But unfortunately, most of the time patients have an incredible adaptation capacity. You see some patients — you can't understand how they could functionally and aesthetically adapt to their dental situation. The oral cavity has a very wide capacity of adapting to pathology. It's mainly us professionals who can open the eyes of the patient with documentation — classical radiography, 3D radiography, intraoral scanning, pictures. What I do also very often is show them some cases of a healthy dentition, so that when they look at their own x-rays and pictures, they can compare. They might not remember what the mouth was looking like years back. So showing this is a healthy dentition, a healthy arch — and this is your situation — all of a sudden, they say, "Oh, wow, it's very different." Aesthetics, to come back to the central question, is one of the key incentives for patients to engage into treatment.

Dr. Seibert: Well, this has been phenomenal. I have so many more questions that I didn't even get a chance to ask you, but tomorrow is a holiday in North America, so we're actually going to begin our holiday travel. Do you have any closing remarks? Because this has been incredible.

Dr. Dietschi: Well, I would say — maybe it's more a philosophical conclusion, if I may say — I believe we need to remain open. We need to remain open to the evolution of the profession. I'm making comparisons, which I believe are not irrelevant to the topic of tooth wear: how long did it take for the profession in general to admit that adhesion is successful? Not only on enamel, which everybody admitted quite early, but also on dentin? It's not such a long time ago that I heard in Congresses, even by big mentors — big names, recognized mentors — that dentin adhesion doesn't work. I think no one will ever say this again in 2025. So it took a couple of decades to admit that adhesion is the key principle that we use to retain our restorations in the mouth.

It means no need for crown lengthening — or very limited need for crown lengthening — limited need for endodontic treatments just to create the conditions to retain mechanically a restoration. Understanding the negative impact of root canal filling on the biomechanics of a tooth and its long-term impact on the tooth's lifespan. All the successes which we have achieved in the field of restorative and prosthetic dentistry go through adhesion.

And we need to understand today that we have different biomaterials, which have different mechanical properties, and each of them is having some indications. I think probably the biggest myth and misconception that we need to find today in the treatment of tooth wear, and in restorative prosthetic dentistry in general, is to believe that only ceramics can work for the patient on a medium-long term. It is a false conception. It's against any modern evidence-based approach and concepts which we have. But indications are not the same. There is no point to fight people who are supportive of composites or those supportive of ceramics. They both have their own indications. Pushing outside its real indication one material or the other is not correct. Each material has its advantages and disadvantages. If the profession can really accept this fact — it's not a concept, it's a fact — I believe we can really do much better for our patients.

Age is a factor. The general biomechanical status of teeth, biofunctional environment — understand also biomechanics, biomechanical environment, functional environment — integrate this with the choice of material. And the last point, very important: there is no scientific rationale to support the fact that all the teeth need to be treated with the same material. I think being more specific — combination of materials — makes a lot of sense, thinking about the resilience of materials which seem at first to be weaker than ceramics, and different kinds of ceramics as well. So again: remain open to a more detailed, specific, and individualized restorative-prosthetic answer to a patient's need. I think this is the biggest aspect on which we need to progress. Remain open. Don't stay back. We don't stay with experience — for the majority of us, it's a very negative factor to evolve, because we are afraid to get out of our comfort zone. I started to realize, maybe 20 years ago, "Okay, I need to find this. Don't continue to do the same because you are used to doing it and you master this protocol and the use of this biomaterial, and you believe it will be the best for the patient and yourself." No. There are new products, there are new protocols, and we need to remain open without jumping too early on something new. But as soon as we have evidence, open our eyes and remain open to improve and do better for our patients.