Free tool
Gum recession stage checker
Seven questions you answer with a mirror and good light. You get a GumScout stage from 0 to 4 with an honest range, what a dentist might call it in plain words, and the one next step.
How to look before you start
Stand at a mirror in daylight or a bright bathroom light. Pull your lower lip down with one finger and look at the four lower front teeth first, then the canines (the pointed ones at the corners), then the side teeth with your cheek pulled back. You are looking for one thing: where the shiny enamel crown ends and the gum begins. On a healthy tooth the gum covers that line. Where the gum has moved away, a band of root shows. Root is slightly yellower and less glossy than enamel, and it often feels a little rougher under a fingernail.
The five GumScout stages
| Stage | What you see |
|---|---|
| 0, no recession seen | The gum meets the enamel edge on every tooth, and the gum between teeth fills the space. |
| 1, slight | A thin band of root on one or two teeth, often a lower front tooth or a canine. |
| 2, mild | Root clearly showing on a few teeth, small triangles starting between teeth. |
| 3, moderate | Root on several teeth, notches at the gum line, clear triangles. |
| 4, advanced | Long roots on many teeth, the gum between teeth lost, often on both arches. |
The stage counts how much root you can see. It is the same scale the GumScout app uses, so a result here and a result in the app mean the same thing.
What a dentist might call it
Dentists chart recession in millimeters with a thin probe, and many also use a class. Two are common:
- Miller classes I to IV (1985) look at how far the recession runs and whether gum and bone between the teeth are lost. Class I and II have nothing lost between the teeth; class III and IV do.
- Cairo types RT1 to RT3 (2011) compare the loss between the teeth with the loss on the front of the tooth. RT1 is none between the teeth; RT2 is some, but no more than on the front; RT3 is more.
Both need a probe, and often an X-ray, so the checker gives the class a dentist might use as a likely range, not a reading. Use it to understand what you hear in the chair.
Try it
Not sure the tooth is receding at all, or is it just long? The receding gums or normal check sorts recession from a tall tooth or normal gum shape.
When to see a dentist
- Soon: gums that bleed on their own, pus, a pimple or a bump on the gum, a swollen gum, a loose tooth, pain, or a tooth that looks longer within weeks. Swelling of the face or jaw with a fever needs care the same day.
- In the next few weeks: root on several teeth (stage 3 or 4), frequent bleeding when you brush, recession you noticed in the last year, or no checkup in over a year.
- At your next checkup: stage 1 or 2 that has not changed. Ask how many millimeters and on which teeth, so you have a number to compare.
Gums do not grow back on their own. What a dentist or periodontist does about recession depends on the cause and how much is showing, and that is their call. The dentist visit prep page has the questions worth asking.
New guides on each stage are on the way. Until then, start here for the basics or see every guide.
Sources
The stage descriptions follow the GumScout app's own scale. The Miller classes follow Miller PD, "A classification of marginal tissue recession", International Journal of Periodontics and Restorative Dentistry (1985). The Cairo types follow Cairo F, Nieri M, Cincinelli S and others, "The interproximal clinical attachment level to classify gingival recessions", Journal of Clinical Periodontology (2011). Causes and warning signs follow the American Academy of Periodontology and the American Dental Association.
Questions
What are the stages of gum recession?
The GumScout stage runs from 0 (no root showing) to 4 (long roots on many teeth, the gum between teeth gone), judged by how much root you can see. Dentists also use the Miller classes (I to IV) and the Cairo types (RT1 to RT3), which look at the gum and bone between the teeth and need a probe to measure.
Is stage 1 gum recession serious?
Usually not on its own. A thin band of root on one or two teeth is common in adults. What matters is whether it moves: take the same photo every month or two, and mention it at your next checkup so your dentist can measure it in millimeters.
Can a dentist fix receding gums?
A dentist can treat what is causing it, such as gum inflammation or hard deposits, and can cover sensitive root or fill a notch. Where a lot of root shows, a periodontist may talk about a gum graft. Gums do not grow back on their own, and which option fits is the dentist's call.
How do I know my stage is right?
You cannot be sure from a mirror. The checker gives a range for that reason. A dentist measures recession with a probe in a few minutes, and photos taken the same way every month show whether the stage is moving, which matters more than the exact number.
Is this a diagnosis?
No. GumScout gives an AI estimate from photos. It is not a dental exam and cannot diagnose gum disease. This checker is a set of questions you answer by eye; a dentist can confirm what is going on.