What are the disadvantages of a dental crown?
The main dental crown disadvantages are that the tooth must be filed down permanently, the nerve can become inflamed and occasionally need a root canal, decay can still start at the crown's edge, and a poorly fitting edge can irritate the gum. Crowns can also chip, loosen or need replacing after some years. At Creative Arts in Dubai, crowns are recommended only when a filling or smaller option cannot protect the tooth.
Who treats you here Dr. Marina Antoniuk Dentist · Dr. Julia General Dentist · Dr. Khalid Saeed Co-founder & Dentist
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Does a crown damage the tooth underneath?
A crown covers the whole visible part of a tooth, so the tooth has to be reduced on every side to make room for it, typically by around one to two millimetres depending on the material. That reduction is permanent: once enamel is removed it does not come back, and the tooth will need a crown or similar cover for the rest of its life. Compared with a filling, which removes only decay, or a veneer, which mainly covers the front, a crown is the most invasive way to restore a tooth that still has its own structure.
That is why the honest question is not "is a crown better?" but "how much healthy tooth is left?" When a large filling, a crack or a root canal has already weakened a tooth, the crown's protection usually outweighs the loss. When the tooth is mostly sound, a filling or bonding is often the better choice. Our guide to crown vs filling explains where the line usually falls.
Dental crown disadvantages and how each is reduced
The common problems with crowns, why they happen, and what good planning and care do about them. Most are not inevitable, but none can be ruled out entirely.
| Disadvantage | Why it happens | How the risk is reduced |
|---|---|---|
| Permanent tooth reduction | Room is needed for the crown material on all sides | Choosing a crown only when needed; materials that allow thinner preparation where suitable |
| Nerve inflammation or a later root canal | Preparation, heat and deep old fillings stress the pulp | Water cooling, a well-fitting temporary, and checking the nerve before starting |
| Decay at the crown's edge | Plaque collects where crown meets tooth | Accurate margins, daily cleaning between teeth, regular checks and X-rays |
| Gum inflammation or recession | A margin that sits too deep or is rough or overhanging | Margin placed in healthy tissue; crown lengthening first where needed |
| Chipping or fracture | Layered porcelain can chip; any ceramic can break under heavy grinding | Material chosen for the bite; a night guard for grinders |
| Sensitivity or a high bite | Freshly prepared dentine; a crown that hits first | Desensitising measures; bite checked and adjusted at fitting |
| Coming loose | Short or tapered tooth, cement washout or decay underneath | Enough tooth for retention; a post and core when needed |
| Colour or shape mismatch | Shade judged under poor light or from a photo | Shade taken in person under controlled light, with a try-in when needed |
Your plan should name the material, the reason a crown is recommended and the alternatives considered.
Can a crowned tooth still decay or need a root canal?
Yes to both. The crown itself cannot decay, but the tooth underneath can, starting at the margin where crown and tooth meet. That edge is a natural plaque trap, especially near the gum and between teeth. Decay there is often invisible until it is advanced, because the crown hides it, which is why X-rays at check-ups matter. Our page on decay under a crown explains the signs and options.
Root canal treatment can also be needed after a crown. The nerve of a tooth that has had deep decay, large fillings or a crack is already under stress, and preparing it for a crown adds to that. Most crowned teeth stay healthy, but a minority develop lingering pain or infection months or years later. Dentists reduce the chance by checking the nerve before preparing, keeping the tooth cool during preparation and protecting it with a well-fitting temporary. When a root canal is needed through an existing crown, it can often be done through a small opening that is then sealed. If decay has reached close to the nerve before the crown, our guide on alternatives to root canal explains when the nerve may still be protected.
The reverse also matters: for back teeth that have had a root canal, a crown is often what keeps the tooth. In one retrospective study, root-canal-treated teeth that were not crowned were lost at about six times the rate of those that were crowned.
What are the disadvantages of zirconia crowns?
Zirconia is very strong and is widely used for back teeth and bridges, but it has its own trade-offs:
- Translucency. Solid (monolithic) zirconia can look more opaque than natural enamel, which matters most on front teeth. Layered zirconia or lithium disilicate (E.max) is often chosen where appearance is critical.
- Chipping of the porcelain layer. In layered zirconia, the outer porcelain can chip off the zirconia core. A systematic review of single crowns (Sailer and colleagues, 2015) reported five-year survival of about 92.1% for zirconia crowns compared with 96.6% for leucite or lithium-disilicate crowns, and more technical problems such as chipping with veneered zirconia.
- Hard to adjust or remove. Its strength means a zirconia crown is slow to cut through if it ever needs replacing or a root canal access.
- Wear on opposing teeth if rough. Well-polished zirconia is generally kind to opposing teeth, but rough or poorly finished surfaces of any ceramic can wear them.
Our comparison of E.max vs zirconia covers where each material fits, and the zirconia crowns page explains how they are made.
Why do some crowns cause bad breath or a black line at the gum?
Bad breath around a crown usually means something is trapping plaque or food: a margin that does not fit closely, an overhanging edge, a gap where food packs between the crown and the next tooth, or decay starting underneath. Gum inflammation around the crown adds to it. Cleaning with floss or interdental brushes often improves things, but a persistent smell or taste from one crown is worth having checked.
A dark line at the gum is most often seen with older porcelain-fused-to-metal crowns, where the metal edge shows as the gum recedes, or where the root underneath has darkened. All-ceramic crowns avoid the metal line but cannot stop gum recession itself. Our page on the dark line around a crown explains the causes and whether replacing the crown helps.
A new crown should not feel high or painful for long
Mild tenderness for a few days after fitting is common. A crown that hits before the other teeth, pain on biting that does not settle, or sensitivity that gets worse rather than better should be checked, because a bite adjustment is often all that is needed.
What are the practical downsides: visits, temporaries and lifespan?
A lab-made crown usually takes at least two visits: one to prepare and scan the tooth, and one to fit the crown, with a temporary crown in between that can feel bulky and occasionally comes off. At Creative Arts, crowns are made by Creative Art Dental Lab in the same building, typically within 3 to 5 working days depending on complexity, and the ceramist can see the tooth in person for shade matching. Same-visit adjustments are possible, but the crown itself is not made on the day.
Crowns are also not permanent. They can last many years with good care, but chipping, decay at the margin, gum changes and wear eventually mean many are replaced. Our guide to how long crowns last covers what shortens or extends their life. And in the first weeks, a new crown that changes the shape of a tooth can make you catch your cheek or tongue, explained in our guide to cheek biting after new crowns.
Not sure a crown is the right choice for your tooth? At Creative Arts in Dubai, dentists explain why a crown is or is not recommended, which material suits it and what the alternatives are, in a written plan.
Restorative dentistryWhen is a crown worth its disadvantages, and when are there better options?
A crown is usually the right choice for a back tooth after a root canal, a tooth with a large filling and little remaining wall, a cracked tooth that needs holding together, or a tooth worn down by grinding. In those cases its drawbacks are smaller than the risk of the tooth splitting.
Smaller options are worth discussing when the tooth is mostly sound: a filling or composite bonding for moderate damage, a veneer for front teeth where the concern is mainly appearance, and partial-coverage restorations, which our guide to inlays and onlays describes. If a tooth is broken below the gum, crown lengthening or a post and core may be needed first, and sometimes replacing the tooth is more predictable; our guide to crowns, veneers, implants and bridges compares them. Dr. Marina Antoniuk, Dr. Julia and Dr. Khalid Saeed set out these options before any tooth is prepared.