Tā de zhìchǐ (zuì hòumian de jiùchǐ) xūyào bá diào.
His wisdom tooth (the rearmost molar) needs to be extracted.
Tips
memory
臼 (jiù) means a mortar — the bowl-shaped tool used for grinding. 臼齿 are your 'mortar teeth' — the flat back teeth designed for grinding food, just like a mortar grinds grain.
