为什么乳牙会自己掉下来？
Why do baby teeth fall out on their own?
当恒牙在牙龈下面慢慢长大，它会轻轻顶着乳牙，让乳牙的根变短直到松脱。这是身体在给更大的牙齿腾地方，一点也不疼。
As the adult tooth grows beneath the gum, it gently pushes the baby tooth until its root shrinks and the tooth loosens. The body is simply making space for bigger teeth, and it does not hurt.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
Gray's Anatomy(格氏解剖学)Elsevier 多版
Susan Standring ed., Gray's Anatomy, Elsevier, various editions
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-7020-5230-9 (Elsevier)
#换牙 #成长
为什么我们有乳牙？
Why do we have baby teeth?
小宝宝刚出生时嘴巴太小，装不下大牙齿，所以先长出小小的乳牙来帮忙吃奶和吃东西。等小朋友长大，乳牙会一颗颗掉下来，让更大的恒牙长出来。
Babies' mouths are too small for big teeth, so they grow tiny baby teeth first to help them eat and drink. As a child grows, these baby teeth fall out one by one to make room for bigger adult teeth.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
Catherine D. Hughes,《First Big Book of the Body》,National Geographic Kids,2012
Catherine D. Hughes, National Geographic Kids First Big Book of the Body, National Geographic Kids, 2012
独立核验依据 · Independent verification: 核验依据 1 DOI 10.1353/bcc.2011.0890
#乳牙 #成长
为什么我们每天要刷牙？
Why do we brush our teeth every day?
吃完东西后，小细菌会在牙齿上留下黏黏的糖，刷牙能把它们赶走，保护牙齿不疼不坏。每天刷两次牙，牙齿就能白白净净、健健康康。
After eating, tiny germs leave sticky sugar on teeth, and brushing sweeps them away so teeth stay strong and pain-free. Brushing twice a day keeps teeth clean and healthy.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
《默克家庭医学手册》Merck Manual Home Health Handbook 中译版,人民卫生出版社
The Merck Manual Home Health Handbook, Chinese ed., PMPH
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9787117181631（按标识回读: 默克家庭医学手册）
#刷牙 #牙齿
为什么牙齿有不一样的形状？
Why do teeth have different shapes?
前面的门牙扁扁的，像剪刀一样切断食物；尖牙能撕开肉类；后面宽宽的磨牙像石磨，把食物磨碎方便消化。不同的形状让牙齿分工合作，吃东西更高效。
Flat front teeth cut food like scissors, pointy canines tear meat, and broad back molars grind it like stones so it is easy to digest. Different shapes let teeth divide the work and eat more efficiently.
难度 入门 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
《格氏解剖学》（Gray's Anatomy, Standring 主编）
Gray's Anatomy (Standring, ed.).
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-7020-5230-9 (Elsevier)
#牙齿 #咀嚼