Reading the tooth numbers on a crown plan
A crown plan is mostly a list of numbers. Once you know the code, you can see exactly which teeth are being treated, with what, and whether that matches what you asked for.
Medically reviewed by Dt. Hüseyin Yavuz Özbek, implant surgeon · Updated October 2026Most clinics outside the USA use the FDI two-digit system. The first digit is the quarter of your mouth (1 upper right, 2 upper left, 3 lower left, 4 lower right, always from your point of view), and the second digit counts back from the middle, from 1 for the front tooth to 8 for the wisdom tooth. So 11 and 21 are your two upper front teeth, and 16 is your upper right first molar. Check every line: the tooth, the material and any work needed underneath, such as a root filling.
When a crown plan arrives, the first thing most people look at is the total. The second thing is a row of numbers like 13, 12, 11, 21, 22, 23, and that is where many people stop reading. That row is the most important part of the plan. It tells you which of your teeth will be filed down and covered, and it is the only way to be sure the plan matches what you thought you were agreeing to.
The code takes about five minutes to learn. After that, you can sit in front of a mirror with your plan and point to every tooth on it.
The FDI two-digit system
There are three tooth numbering systems in wide use: the Zsigmondy or Palmer grid, the American "universal" system that numbers teeth 1 to 32, and the FDI two-digit system. A review in the Journal of Dental Education described the FDI system as used throughout the world except the USA, and the FDI World Dental Federation has long pushed for more countries to adopt it. Clinics in Turkey and most of Europe write plans this way, so it is the one to learn.
Every tooth gets two digits. Read them separately, not as a single number. Tooth 21 is "two-one", not "twenty-one".
The first digit: which quarter of your mouth
- 1 is your upper right
- 2 is your upper left
- 3 is your lower left
- 4 is your lower right
The quarters go round in a circle: start at your upper right, move across to the upper left, drop to the lower left, and come back across to the lower right. Right and left are always yours, not the dentist's. That catches people out, because a chart drawn as if you are facing the dentist puts your right side on the left of the page.
Baby teeth use 5 to 8 for the four quarters instead. You will only see those on an adult plan if a baby tooth never fell out, which does happen.
The second digit: which tooth in that quarter
Count back from the middle of your mouth:
| Second digit | Tooth | Where it is |
|---|---|---|
| 1 | Central incisor | Front tooth, next to the midline |
| 2 | Lateral incisor | The smaller tooth beside it |
| 3 | Canine | The pointed "eye tooth" at the corner of the smile |
| 4 | First premolar | First of the two smaller back teeth |
| 5 | Second premolar | Second of the two |
| 6 | First molar | The first big chewing tooth |
| 7 | Second molar | Behind it |
| 8 | Third molar | The wisdom tooth, if you have one |
Put the two digits together and you can name any tooth. 11 is your upper right front tooth. 23 is your upper left canine. 36 is your lower left first molar. 47 is the second molar on your lower right.
What common smile plans look like in numbers
Cosmetic crown plans usually cover the teeth that show when you smile, counted outwards from the middle. Once you know the pattern you can tell the size of a plan at a glance:
- Six upper teeth: 13 12 11 21 22 23. Canine to canine.
- Eight upper teeth: 14 to 24, which adds the first premolars.
- Ten upper teeth: 15 to 25, which adds the second premolars.
- The lower arch: the same pattern with 4 and 3, for example 43 42 41 31 32 33.
A plan written as "14–24" or "15–25" means every tooth in between. If you see "10 upper, 10 lower", that is twenty teeth, and twenty teeth that will each need a crown for the rest of your life. Our page on full-mouth crowns goes into what that commitment looks like.
How wide your smile is decides how many teeth show. Some people show only six upper teeth when they smile; others show ten or more. This is one reason two plans for "a new smile" can look very different, and a fair reason to ask why a plan stops or starts where it does.
Reading the rest of each line
A good plan gives every tooth its own line, or groups teeth that get identical treatment. Beside the number you should see what is being done and what it is made of. The common shorthand:
- Zr, zirconia, monolithic zirconia: a zirconia crown. See our zirconia crowns page.
- E-max, e.max, LiSi2 or lithium disilicate: a glass-ceramic crown, often chosen for front teeth. See E-max crowns.
- PFM or MC: porcelain fused to metal.
- RCT or endo: root canal treatment before the crown.
- Post and core: a post placed in a root-filled tooth to hold the crown.
- Ext or X: extraction.
- Pontic: a false tooth in a bridge, sitting over a gap rather than on a tooth.
- Bridge 14–16: a single piece joined across those teeth, usually with the middle one (15) as the false tooth.
Our guide to crown types explains how the materials differ. On the plan itself, what you want is a clear answer for every number: this tooth, this treatment, this material.
Five checks to do with a mirror and the plan
Lay the plan out, stand in front of a mirror, and work through it tooth by tooth.
1. Does the count match what you asked for?
If you asked to fix two chipped front teeth and the plan says 15 to 25, that is ten teeth. Sometimes there is a good reason, such as matching colour across the smile. Sometimes there is not. Either way you should hear the reason before you agree.
2. Is it really crowns?
Check the word next to each number. In a 2022 BBC report, a woman who travelled for what she understood to be 26 veneers later learned the work was crowns. Veneers and crowns are very different treatments, and our page on crowns vs veneers explains how. The plan should use one word or the other, not something vague like "smile design".
3. Which of these teeth are healthy?
Point to each tooth on the list and ask yourself whether anything is actually wrong with it. A heavily filled, cracked or root-filled tooth is a different case from a sound tooth that is just a little darker or slightly out of line. We would rather protect a healthy tooth than crown it, and a good plan should explain the reason for every sound tooth it includes. Our article on whether you really need a crown covers the alternatives.
4. What happens before the crown?
Look for lines about decay, gum treatment, root canal work or extractions. If your X-ray shows a problem, the plan should deal with it before any crown goes on. With us, any decay or infection is treated first. If a tooth has had a root filling, our piece on root-filled teeth and posts explains when extra support is needed.
5. Is there anything you cannot translate?
Circle it and ask. The General Dental Council's standards say UK dentists must give a written treatment plan before treatment starts, including the proposed treatment and a realistic cost. Clinics abroad work under their own rules, but you can still expect the same clarity and walk away if you do not get it. The GDC's advice for people going abroad is blunt: ask plenty of questions, and do not feel you have to commit on the day.
When your UK notes use a different system
If you have older notes from a UK dentist, you may see teeth written as a single number with a little corner bracket, such as a 1 with the bracket opening to one side. That is the Palmer or Zsigmondy grid: each quarter is drawn as a corner and the teeth are numbered 1 to 8 from the middle. The same tooth can therefore appear as "1" in a bracket on a UK note and "11" on a plan from abroad.
The American system is different again. It numbers all 32 adult teeth in one sequence, starting at the upper right wisdom tooth. A plan using it is uncommon in the UK or Turkey, but it can turn up in apps and online forms. If a number above 48 or a plain "8" appears with no quarter, ask which system is being used before you assume anything.
When you want two dentists to compare notes, it helps to have your own records. In the UK you can ask any dental practice for a copy of the personal information it holds about you, which includes notes and X-rays. The Information Commissioner's Office calls this a subject access request and says organisations usually have one month to respond. Our guide to getting a second opinion on a crown plan covers what to send and what to ask.
A worked example
Imagine a plan with these lines:
- 11, 21: E-max crowns
- 12, 22, 13, 23: E-max crowns
- 14, 24: zirconia crowns
- 26: RCT, post and core, zirconia crown
- 36: filling
In plain English, that is eight crowns across the upper smile from first premolar to first premolar, with the six front teeth in E-max and the two premolars in zirconia. Your upper left first molar needs a root canal, a post and a zirconia crown. Your lower left first molar needs a filling. Now you can ask useful questions. Why are 14 and 24 included? What is wrong with 26? Could 12 and 22 be left alone if they are healthy? If you want prices for each item, our crown prices page lists them per tooth.
Getting a plan you can read
If you would like a plan that lists each tooth by number, says what we would do with it and explains why, send us your X-rays and a few photos. Our free written plan comes before you book anything, so you can check it line by line, show it to your own dentist, and take your time.
Common questions
Why does my plan say 11 and 21 instead of my front teeth?
That is the FDI two-digit system. The first digit is the quarter of the mouth (1 is upper right, 2 is upper left) and the second digit is the position counting back from the middle. So 11 and 21 are your two upper front teeth.
My UK dentist wrote numbers in a little grid instead. Is that different?
Probably. That is the Palmer or Zsigmondy style, where a tooth is written as a number from 1 to 8 inside a corner bracket showing the quarter of the mouth. The teeth are the same; only the notation changes. Ask either dentist to translate if anything is unclear.
Is right and left on the plan my right and left?
Yes. Tooth numbers are always given from the patient's side. On a chart drawn as if you are facing the dentist, your right side appears on the left of the page, which is why it can look back to front.
What if the plan has more teeth on it than I expected?
Ask why, tooth by tooth. Some plans add teeth to make a smile look even, and some add teeth that need repair anyway. You should get a reason for each one. Our guide to whether a tooth needs a crown lists the questions to ask.
Can I get my plan written out in plain English as well?
You can ask for that from any clinic. A good plan explains the treatment, the material and the cost for each tooth. Our free written plan lists every tooth by number and says what we suggest for it and why. Ask for one here.
Sources
- Peck S, Peck L (1993). A time for change of tooth numbering systems. Journal of Dental Education
- Journal of the Irish Dental Association (1988). FDI Director calls on more countries to adopt the FDI two-digit tooth-numbering system
- General Dental Council. Standards for the Dental Team, Principle 2: Communicate effectively with patients
- General Dental Council. Going abroad for dental treatment
- BBC News (2022). Turkey teeth: Are cut-price reality TV teeth worth it?
- Information Commissioner's Office. Getting copies of your information (SAR)
Checked October 2026. Where we give our own view as a clinic, we say so.
Send a selfie smile. Get a written crown plan.
A few photos of your teeth or a recent X-ray is enough to start. A dentist looks at them and you get a written plan: which teeth, which material, why, and the price in pounds. If you don't need crowns, we'll tell you.