When a crown is the right answer
A crown is a cap that covers a whole tooth, and its job is to hold a weakened tooth together. A filling replaces missing tooth material. A crown takes over the outside of the tooth so the biting forces squeeze it rather than split it. That distinction is the whole decision.
Typical reasons
- After a root canal on a back tooth. Root-treated teeth are more brittle and need covering.
- A cracked tooth. A crown holds the segments together; a filling would act like a wedge.
- A large old filling that is failing. Once more than about half the tooth is filling, there is not enough tooth left to support another one.
- A badly worn tooth, usually from grinding.
- On top of a dental implant, where the crown is the visible tooth.
What crowns are made of
All-ceramic and zirconia look the most natural and are the usual choice for anything that shows. Zirconia is also extremely strong, which makes it good for molars and for grinders. Porcelain fused to metal is strong and long-proven but can show a dark line at the gum as gums recede. Gold is kind to the opposing teeth and lasts a very long time, and is still the right answer for some back teeth if you do not mind the colour. We will tell you which we would choose for your tooth and why.
The appointments
- Preparation. The tooth is numbed and shaped so the crown has room, any decay is removed, and the tooth is built up underneath if needed. A scan or impression goes to the lab, and you leave in a temporary.
- Fitting. The permanent crown is tried in, checked for fit, shade and contact with the neighbours, then cemented and the bite adjusted. Adjusting the bite properly is what prevents soreness afterwards.
Between the two, avoid sticky foods on that side — temporaries are designed to come off easily. If one does come off, keep it and call us.
Making a crown last
Crowns commonly last 10 to 15 years and often longer. What ends them is almost never the crown material — it is decay at the margin where the crown meets the tooth, which is a flossing problem, or a fracture from grinding, which is a night guard problem. The crowned tooth can still get decay underneath, so it needs the same care as any other tooth.
Crown, or something else?
For a small chip on a front tooth, bonding or a veneer keeps far more tooth. For a moderate cavity, a filling is still the right call. A crown is a bigger intervention, and it is the right one when what is left of the tooth cannot hold itself together.
