Root Canal Through a Crown in 2026
Yes — a dentist can usually drill a small access hole through an existing crown to do the root canal, keeping the crown. That costs about $1,300-$2,300 all-in versus $2,000-$4,100 to replace the crown, saving roughly $1,000-$1,500. The catch: drilling can fracture brittle ceramic, and that replacement is on you.
Save the crown vs replace it: the cost gap
Whether you can drill through the crown decides how much the whole treatment costs. The chart below puts both paths — saving the crown through an access hole versus replacing it — on one shared scale, by tooth type, so the savings are clear at a glance.
All-in totals: root canal plus either a composite access patch (save) or a new crown (replace), by tooth type. Source: Real Dental Costs — compiled from published payer and provider fee data (2024-2026).
How the access-hole technique works
The goal is to reach the nerve chamber without destroying the crown:
- Access — the dentist drills a small hole (about 3-4mm) through the chewing surface of the crown.
- Treatment — files go through that hole to clean, shape and seal the root canals exactly as in a normal root canal.
- Patch — once the canals are sealed, the access hole is filled with tooth-coloured composite.
You keep your crown; it now carries a small filling on top. This is a routine procedure called an endodontic access preparation.
What it costs, and what you save
The math is simple once you separate the two paths:
| Path | Procedure | Restoration | Typical all-in |
|---|---|---|---|
| Save the crown | Root canal ($600 – $1,600) | Composite patch ($150 – $300) | $1,300 – $2,300 |
| Remove and replace | Root canal ($600 – $1,600) | New crown ($800 – $2,500) | $2,000 – $4,100 |
Drilling through the crown commonly saves around $1,000-$1,500 — but only if the crown survives. If it cracks, you pay for the replacement anyway, which is why the choice is partly a bet on the crown's durability.
The fracture risk
Drilling vibration against ceramic behaves like drilling glass — micro-cracks can form, so there is roughly a 10-20% chance the crown chips or fractures during or shortly after the procedure. Because this is a disclosed, known risk, the replacement cost falls on you, not the dentist, unless there was negligence. Most dentists have you sign a consent form before drilling.
Crown material matters
| Crown material | Drillability | Fracture risk |
|---|---|---|
| Gold / metal & PFM | Easy — metal cuts smoothly | Low |
| Zirconia | Hard — very tough to drill | Low |
| E-max / older all-porcelain | Brittle | Higher |
Ask your dentist what your crown is made of. If it is a vintage porcelain-fused-to-metal crown, the porcelain coating can chip during drilling and expose the metal underneath, which looks worse even if the core survives.
When the crown must come off
Drilling through the top is not always possible:
- Recurrent decay at the margins — if X-rays show decay creeping under the crown at the gumline, the crown must be removed so the dentist can clean out the rot. Drilling only through the top would seal the decay inside.
- A leaking or ill-fitting crown — if the existing crown no longer seals well, saving it just delays a replacement.
- A very old crown (10+ years) — saving it often means redoing the work in a couple of years, so replacing now is frequently better value.
Get the right specialist
If your general dentist says the crown has to be replaced, get a second opinion from an endodontist before agreeing. Specialists work under a microscope with fine instruments and are more practised at cutting a clean access hole without shattering the ceramic — which can be the difference between keeping your crown and buying a new one.
Related crown and root canal guides
Dental Crown Cost
By material, with and without insurance.
Root Canal Cost
Front, premolar and molar prices.
Crowns on Front Teeth
E-max vs zirconia vs PFM for the smile zone.
Recementing a Loose Crown
What it costs and the superglue warning.
Root Canal vs Extraction
Cost, pain and the price of pulling a tooth.
Broken Tooth: Bond vs Crown
Repair cost for bonding, crown and root canal.
Frequently asked questions
Can you do a root canal through an existing crown?
How much does a root canal through a crown cost?
Will drilling through the crown damage it?
Who pays if the crown breaks during the root canal?
Does the crown material affect whether you can drill through it?
When can't you save the existing crown?
Is it better to save an old crown or replace it?
Should I see a general dentist or an endodontist for this?
Independent dental pricing research — every series carries a named source, and corrections are logged publicly. Not medical advice.