A crown covers a tooth completely. Most people call it a cap, and it’s the same thing. Cap is the everyday word, and crown is the one on the treatment plan. It’s what we use when there isn’t enough solid tooth left to hold a filling, or when a tooth has cracked and needs to be held together, not just patched.
It’s also the point where a tooth stops being repaired and starts being rebuilt, so we’ll say this up front: a crown can’t be undone. Preparing a tooth for one removes structure that doesn’t grow back. That’s not an argument against crowns, which are one of the most reliable things in dentistry. It’s a reason to be sure you need one.
When a crown is the answer, and when it isn’t
The first thing we ask is whether something smaller will do.
A crown makes sense when:
- An old filling is failing and there’s now more filling than tooth.
- The tooth has cracked, or has a crack line that will keep spreading every time you bite.
- The tooth has had a root canal, especially a back tooth that does heavy chewing.
- Wear has taken off enough height that the tooth no longer meets the tooth opposite it properly.
It’s the wrong answer when a filling or a more conservative restoration would rebuild what’s missing and leave the rest of the tooth standing. We look at those first, and if one will work, we’ll tell you.
We lean toward keeping tooth structure. Your body can’t make more enamel, and every crown trades some of it for strength and protection. That trade is worth making on a cracked molar. It isn’t worth making on a tooth that just needs a good filling.
Why we stopped making crowns in the office
In 2000 we bought the first CEREC machine in Las Vegas. For years after that, we designed and milled crowns right here and put them in the same day. We know the technology well, because we were using it before most dentists had seen one.
We don’t do it anymore, and the reason is the bite.
A crown isn’t just a cap on a tooth. It’s a brand-new chewing surface. Where that surface meets the opposing tooth, and how it behaves when your jaw slides sideways, really matters. If it’s a little high or in the wrong spot, the problem doesn’t stay with that tooth. It shows up in the muscles and the jaw joint, which is a big part of what this practice treats.
Two things convinced us to go back to having a lab make our crowns.
- A technician can match the material to the situation. A skilled lab makes the crown from whatever suits that tooth, in that bite, and making crowns well is their whole job.
- The temporary does real work. It isn’t just something to keep you comfortable until the real crown arrives. It’s a trial run. You chew on it, and if something is high or feels wrong, we find out before anything is permanently cemented. For us, that has meant far fewer bite and jaw problems than we had to deal with in our same-day years.
This is our preference, not a judgment on anyone else. Same-day crowns are good technology, and plenty of dentists do excellent work with them. This is just what we’ve found works better for our patients and the kinds of bites we see most.
What about an onlay?
Saving tooth structure was the whole reason we bought that machine. An onlay rebuilds the part of the tooth that’s missing and leaves the walls standing, instead of shaping down the whole tooth, and we placed a lot of them. Plenty are still going strong more than twenty years later.
Since then we’ve moved toward full crowns for most of our patients, and it’s not because onlays fail.
There isn’t much research comparing the two. A 2022 systematic review and meta-analysis found no statistically significant difference in survival between onlays and full crowns on back teeth at one year or at three, and the longest study it included actually favored onlays. But it combined five observational studies with a single randomized trial, all with short follow-up, so it isn’t strong evidence either way.
Wang B, Fan J, Wang L, Xu B. Onlays/partial crowns versus full crowns in restoring posterior teeth: a systematic review and meta-analysis. Head Face Med. 2022;18(1):36. The authors conclude that onlays performed as well as full crowns in the posterior region over the short term, and call for randomized trials with long-term follow-up.
The real reason is the kind of mouths we usually see. By the time most people come to us, their teeth have often been wearing down for years. On a worn tooth, there often isn’t enough solid structure left for an onlay to be the conservative choice it was designed to be.
So it depends on your stage of life and on the tooth itself. A younger tooth with a failing filling and good structure around it is exactly what an onlay is for, and we still place them. A worn set of teeth being rebuilt to a new bite is a different problem, and full crowns handle it better. We decide this tooth by tooth. It isn’t a blanket policy.
We choose the material for the tooth
Three materials cover almost everything we do, and we keep the list short on purpose.
- Zirconia. The strongest of the three. It’s what we usually want on back teeth, for heavy grinders, and anywhere the forces are high enough that a weaker material would be asking for trouble.
- e.max, pressed lithium disilicate. The best-looking, and strong enough for most situations. It’s usually the choice toward the front of the mouth, where a crown has to blend in with the teeth around it and not just hold up.
- Gold. Still the longest-serving material in dentistry. It needs the least tooth removed because it can be made thin, it seals beautifully at the edge, and it wears at about the same rate as enamel, so it’s gentle on the tooth it bites against. The only problem with gold is that it looks like gold, which is why it goes in the back of the mouth or not at all.
Which one suits your tooth is something we talk through with you, and it’s best to have that conversation before the tooth is prepared, not after.
What getting a crown is like
Two appointments, a couple of weeks apart.
- The first visit. We numb the tooth and prepare it, record the prepared tooth and how your bite closes, and send you home in a well-made temporary. This visit usually takes longer than people expect, because the preparation and those records decide whether the final crown fits.
- In between. Chew on it. People tend to think of this as waiting time, but it isn’t. If the temporary feels high, catches when you slide your jaw sideways, or the tooth aches afterward, call us. That’s much more useful to know now than after the final crown is cemented.
- The second visit. We take off the temporary, try in the crown, and check the fit, the contacts on each side, and the bite in every direction before anything is cemented. Then it goes on.
Scan or impression? Usually a digital scan, with the same scanner we use at your exam, so there’s no tray and nothing to gag on. We’ve kept traditional impression material for cases where a scan has trouble, and for cases where it’s simply the easier way to get an accurate record. What matters is how accurate the record is, not which tool made it.
After a root canal
A back tooth that’s had a root canal usually needs a crown afterward, and it’s the part people are least ready for. A root canal hollows out the inside of the tooth, and the tooth has often already lost a lot of structure to the decay or crack that made the treatment necessary. What’s left is more brittle and splits more easily when you chew.
The crown is what prevents that. We plan it as part of the same treatment, not as a surprise later, and we’ll tell you at the start that it’s coming. A root canal and a crown on one tooth is a real sequence with a real cost, and you should hear about it up front. Our article on dental insurance explains why that combination often uses up an annual maximum on its own.
If you’re still wondering whether the tooth needs treatment at all, our article on the signs you may need a root canal covers what actually points to a problem inside the tooth.
How long a crown lasts
A well-made crown on a well-cared-for tooth lasts a long time, often more than ten years and frequently much longer. It helps to know what usually ends one, because it’s rarely the crown itself.
- Decay at the edge. The crown can’t decay, but the tooth right where the crown meets it can, and that’s the most common reason a crown gets replaced. If it’s caught early, it can sometimes be fixed with a small composite repair instead of a new crown.
- The bite. A crown that takes more force than it should, or hits wrong when your jaw moves sideways, will chip or come loose. This is the problem we work hardest to design out.
- The tooth underneath. Sometimes the crown is fine and the root or the gum around it isn’t.
None of that is a reason to hold off. It’s why we look at your crowns at your cleanings and take X-rays once a year, so every edge gets checked on a regular schedule. An edge that’s starting to leak is a small repair when it’s found early, and a much bigger one when it’s found because the tooth started to hurt.
If you’ve been told you need a crown
Bring the treatment plan and we’ll go through it with you: whether the tooth really needs a full crown, what it would take to save more of it, which material fits, and what the steps and the cost look like before anything starts. Call us at 702-734-0776.