Tooth Number 25: Lower Right Central Incisor

When tooth 25 comes in behind a baby tooth

Lower adult front teeth sometimes come in behind the baby teeth instead of pushing them out from below. In one study of children aged 5 to 7½ with this pattern, about 7 in 10 lost the baby teeth on their own without treatment, and about 15% needed a baby tooth removed.

Early crowding often eases. A review cited by the AAPD found that crowding of the lower front teeth in the mixed-teeth years tended to decrease over time, and the more crowding there was, the more it improved on its own. Some children's crowding got worse, though.

The same tooth on the left side, tooth 24, has its own section on tartar and crowding that comes back.

Where is tooth 25?

Tooth 25 is one of the two bottom front teeth right in the middle of your mouth: the one on your right side.

In a mirror, tooth 25 shows on the right side of your reflection. Someone looking into your mouth sees it on their left.

Right next to it, across the middle, is tooth 24, the other lower central incisor. Behind it is tooth 26, the lower right lateral incisor.

Its mirror twin on the left side is tooth 24. The tooth in the same spot in the upper jaw is tooth 8, the upper right central incisor.

Dental charts show the patient's right side on the left, so tooth 25 sits just left of the center line of the bottom row. Lower right teeth finish the circle, from 25 (the front tooth) to 32 (the wisdom tooth).

What does the lower central incisor do?

Incisors have a thin, straight biting edge for cutting into food. They are the most visible teeth in the mouth. The lower central incisors are the smallest teeth in the adult mouth and the smallest of all the incisors.

Common problems with lower central incisors

• Cavities and chips. 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 25 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.

When does tooth 25 come in?

Both the ADA and AAPD charts give 6–7 years for the lower central incisors.

Tooth 25 replaces the lower right baby central incisor (tooth P), which usually falls out at 6–7 years (ADA).

In the ADA chart, they are among the first to come in, along with the upper first molars and the lower first molars. In the AAPD's 13-step order, from the first molars (step 1) to the wisdom teeth (step 13), they are step 2.

Under the gum, according to the AAPD chart, it starts to harden (calcify) at about 3–4 months, has a finished crown by 4–5 years and has a finished root by about 9–10 years, a few years after it comes into the mouth.

How many roots does tooth 25 have?

One narrow root, flattened from side to side.

Tooth 25 in FDI and Palmer notation

"25" in FDI is a different tooth. Read as an FDI code, 25 means the upper left second premolar (tooth 13 in Universal). Charts and X-ray reports from outside the US often use FDI, so check which system is in use.

"41" can only be FDI. Universal numbers stop at 32, so a tooth 41 on any chart is this tooth.

Palmer needs the bracket. Every quarter of the mouth has a tooth 1 in Palmer notation; only the ┐ (or the letters LR) makes it this one.

All adult teeth in the lower 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 25

• 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.
• Knocked-Out Tooth Rescue: first aid for a knocked-out adult tooth.
• 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 Dental Association (MouthHealthy). Primary Tooth Development (eruption chart). 2012. Accessed October 26, 2026.
3. American Academy of Pediatric Dentistry. Dental Growth and Development (chronology after Logan & Kronfeld 1933, adapted 2003). Accessed October 26, 2026.
4. American Academy of Pediatric Dentistry. Management of the Developing Dentition and Occlusion in Pediatric Dentistry (Reference Manual of Pediatric Dentistry). latest revision 2024. Accessed October 26, 2026.
5. World Health Organization. Oral health surveys: basic methods, 5th edition (tooth notation after ISO 3950). 2013. Accessed October 26, 2026.
6. Nelson SJ. Elsevier. Wheeler's Dental Anatomy, Physiology and Occlusion, 11th edition. 2019.
7. American Dental Association. ADA Dental Claim Form (tooth designation systems). Accessed October 26, 2026.
8. Dentalcare.com (continuing education course CE500). An Overview of Dental Anatomy: Types of Teeth and their Functions. Accessed October 26, 2026.
9. Cleveland Clinic. Teeth: Anatomy, Types, Function & Care. last updated January 26, 2023. Accessed October 26, 2026.
10. Aminabadi NA, Farahani RM, Sohrabi A, Pouralibaba F. Journal of Contemporary Dental Practice 10(1):25–32. Lingual eruption of mandibular permanent incisors: a space correlated phenomenon?. 2009. Accessed October 26, 2026.

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