Which tooth erupts last in the permanent dentition in both males and females?

Explanation

## Permanent Dentition Eruption Sequence **Key Point:** The **third molar (wisdom tooth)** is the last tooth to erupt in the permanent dentition, typically between 17–25 years of age, though considerable individual and population variation exists. ### Eruption Timeline of Permanent Teeth | Tooth Type | Eruption Age (Years) | Sex Difference | |-----------|----------------------|----------------| | Central incisor | 6–7 | Minimal | | Lateral incisor | 7–8 | Minimal | | Canine | 9–10 | Females earlier by ~6 months | | First premolar | 10–11 | Females earlier by ~6 months | | Second premolar | 11–12 | Females earlier by ~6 months | | First molar | 6 | Minimal | | Second molar | 12–13 | Females earlier by ~6 months | | **Third molar** | **17–25** | **Highly variable; females slightly earlier** | **High-Yield:** The **third molar** is the **last erupting tooth** and shows the **greatest individual and ethnic variation**. Its presence or absence, along with its stage of eruption or impaction, is a key forensic marker for age estimation in the 17–25 year age group. **Clinical Pearl:** Third molars may never erupt (agenesis) in 15–35% of the population, or may remain impacted. This variability makes them less reliable than earlier-erupting teeth for precise age determination but still useful as an upper-limit indicator. **Mnemonic:** **"Wisdom comes last"** — The third molar (wisdom tooth) erupts last, reflecting the saying that wisdom comes with age and maturity. ### Forensic Significance 1. **Presence of erupted third molars** → individual is likely **≥17 years old** 2. **Absence or impaction of third molars** → does NOT rule out age ≥17 (due to agenesis/impaction) 3. **Root development stage of third molars** → can narrow age estimate within 17–25 range using Demirjian or similar staging systems