Tooth Number 2: Upper Right Second Molar

Sealants and brushing tooth 2

Upper second molars come in at about 12–13 years (ADA), so they can be sealed in the early teens. The CDC reports that sealants prevent 80% of cavities over 2 years in the back teeth, where 9 in 10 cavities occur, yet only about half of teens aged 12 to 19 (48%) have them.

Hard to reach. Sitting far back, it is easy to miss when brushing. Angle the brush so the bristles reach its back and cheek sides.

Back teeth stay a problem spot into adulthood: the CDC notes that adults aged 20 to 34 have more untreated cavities in their back teeth than any other age group.

The same tooth on the left side, tooth 15, has its own section on how close it sits to the sinus.

Where is tooth 2?

Tooth 2 is in your upper jaw on your right side. It is the seventh tooth from the middle: start at the gap between the two top front teeth and count 7 teeth toward the back on your right side.

In a mirror, tooth 2 shows on the right side of your reflection. Someone looking into your mouth sees it on their left.

In front of it (toward the middle) is tooth 3, the upper right first molar. Behind it is tooth 1, the upper right wisdom tooth.

Its mirror twin on the left side is tooth 15. The tooth in the same spot in the lower jaw is tooth 31, the lower right second molar.

Dental charts show the patient's right side on the left, so tooth 2 sits on the left half of the top row. Universal numbers start here: upper right teeth run from 1 (the wisdom tooth) to 8 (the front tooth).

When does tooth 2 come in?

The upper second molars usually come in at 12–13 years according to the ADA chart. The AAPD chart gives 12–14 years.

In the ADA chart, they usually come in after the lower second molars (11–13 years) and before the upper wisdom teeth (17–21 years). In the AAPD's 13-step order, from the first molars (step 1) to the wisdom teeth (step 13), they are step 12.

Under the gum, according to the AAPD chart, it starts to harden (calcify) at about 30–36 months, has a finished crown by 7–8 years and has a finished root by about 14–16 years, a few years after it comes into the mouth.

What does the upper second molar do?

Molars do the heavy grinding. Cleveland Clinic notes that about 90% of chewing happens on the molars. The upper second molar is a little smaller than the first molar in front of it, and its three roots are usually closer together.

It is also called the "12-year molar". Second molars are named for the age they usually arrive, about 12 years.

Adult molars don't replace any baby tooth. They come in behind the baby teeth as the jaw grows. Upper second molars usually complete the set of 28 adult teeth before any wisdom teeth arrive.

How many roots does tooth 2 have?

3 roots (two cheek-side, one palate-side), usually less spread out than the first molar's.

Common problems with upper second molars

• Treatment. Small cavities are fixed with a filling. If decay or an injury reaches the nerve, root canal treatment can save the tooth, often followed by a crown.

If tooth 2 hurts, feels loose, or the gum around it swells, the Dental Emergency Checker can help you decide how soon to see a dentist. Swelling that spreads to the eye or neck, or makes it hard to breathe or swallow, is an emergency: call 911. These are typical problems for this kind of tooth, not a diagnosis.

Tooth 2 in FDI and Palmer notation

A lone "2" can only be Universal. FDI codes always have two digits, so 2 on its own is never an FDI number.

On a US chart, "17" is a different tooth. Universal 17 is the lower left wisdom tooth (tooth 17), so "tooth 17" only means this tooth when the chart uses FDI.

Palmer needs the bracket. Every quarter of the mouth has a tooth 7 in Palmer notation; only the ┘ (or the letters UR) makes it this one.

All adult teeth in the upper right quarter

From the front of the mouth to the back:

The Tooth Number Chart & Converter converts any tooth between the three systems.

Tools for tooth 2

• Adult Teeth Predictor: likely dates for your child's adult teeth.
• Dental Emergency Checker: how soon to see a dentist if it hurts or breaks.
• Dental Numbness Calculator: how long numbness lasts after a filling.
• Dental Insurance Calculator: what your plan may pay for a crown or root canal.
• How Long Does Dental Work Last?: how long fillings, crowns, veneers and implants usually last, from long-term studies.
• Dental Treatment Plan Decoder: plain English for treatment-plan shorthand like "#30 MOD comp".

Frequently asked questions

Sources

1. American Dental Association (MouthHealthy). Permanent Tooth Development (eruption chart). 2012. Accessed October 26, 2026.
2. American Academy of Pediatric Dentistry. Dental Growth and Development (chronology after Logan & Kronfeld 1933, adapted 2003). Accessed October 26, 2026.
3. World Health Organization. Oral health surveys: basic methods, 5th edition (tooth notation after ISO 3950). 2013. Accessed October 26, 2026.
4. Nelson SJ. Elsevier. Wheeler's Dental Anatomy, Physiology and Occlusion, 11th edition. 2019.
5. American Dental Association. ADA Dental Claim Form (tooth designation systems). Accessed October 26, 2026.
6. Dentalcare.com (continuing education course CE500). An Overview of Dental Anatomy: Types of Teeth and their Functions. Accessed October 26, 2026.
7. Dentalcare.com (continuing education course CE500). An Overview of Dental Anatomy: Permanent Dentition. Accessed October 26, 2026.
8. Cleveland Clinic. Teeth: Anatomy, Types, Function & Care. last updated January 26, 2023. Accessed October 26, 2026.
9. Centers for Disease Control and Prevention. Dental Sealant Facts. May 15, 2024. Accessed October 26, 2026.

Last reviewed October 26, 2026 by the Dental Health Time editorial team, against the sources above. How we review.