Year 4 Science: Types of teeth
Part of the Year 4 Science teeth and the digestive system chapter. Chapter overview · whole chapter on one page
Types of teeth
Humans have four types of teeth, and each one has a different shape and job. The incisors at the front cut food. The canines are pointed, and tear food. The premolars and molars at the back crush and grind food.
An adult has 32 teeth. The table gives the number of each type.
| Type of tooth | Number in an adult | Job |
|---|---|---|
| Incisors | 8 | cut food; they are sharp and at the front |
| Canines | 4 | tear food; they are pointed |
| Premolars | 8 | crush and chew food; they are at the back |
| Molars | 12 | grind food; they are the big, flat teeth at the back |
| Total | 32 |
Key ideas
- Incisors cut food, and are at the front.
- Canines are pointed, and tear food.
- Premolars and molars are at the back, and crush and grind food.
- An adult has 32 teeth altogether.
Method. Read the table.
- Find the row. The incisors row shows the number of incisors in an adult.incisors
- Read the number. An adult has 8 incisors.8
- Write the answer. 8
Check. Incisors are the front teeth that cut food. ✓
Method. Add the four types of tooth.
- Add them. 8 incisors, plus 4 canines, plus 8 premolars, plus 12 molars.8 + 4 + 8 + 12
- Find the total. The total is 32 teeth.32
- Write the answer. 32
Check. The table total is 32 too. ✓
Method. Find the pointed teeth.
- Read the table. Canines are pointed, and they tear food.pointed
- Name them. So the pointed teeth are the canines.Canines
- Write the answer. Canines
Check. Canines sit beside the incisors. ✓
Watch out
Watch out: a canine is not a molar. A canine is pointed and tears food, while a molar is a large, flat tooth at the back that grinds.
Try it at home or school (with a grown-up). Look in a mirror with a grown-up. Count the teeth at the front of your mouth, and find a pointed tooth. Do not touch your teeth with sharp objects.
Exam tip
Grown-up tip. Ask: “Which teeth do you use to bite an apple? Which teeth do you use to chew bread?” Let your child name the type of tooth they use for each food.
Exercise 5C Types of teeth
Method. Read the table in section 5.3.
- Read the row. The incisors row says 8.8
- Write the answer. 8
Check. Incisors are at the front of the mouth. ✓
Method. Read the table in section 5.3.
- Read the row. The canines row says 4.4
- Write the answer. 4
Check. Canines are next to the incisors. ✓
Method. Read the table in section 5.3.
- Read the row. The premolars row says 8.8
- Write the answer. 8
Check. Premolars are at the back of the mouth. ✓
Method. Read the table in section 5.3.
- Read the row. The molars row says 12.12
- Write the answer. 12
Check. Molars are the largest teeth at the back. ✓
Method. Add the four types of tooth.
- Add them. 8 plus 4 plus 8 plus 12 makes 32.8 + 4 + 8 + 12 = 32
- Write the answer. 32
Check. The total in the table is 32. ✓
Method. Read the table in section 5.3.
- Read the job column. The incisors cut food.cut food
- Write the answer. Incisors
Check. Incisors are the sharp front teeth. ✓
Method. Read the table in section 5.3.
- Read the job column. The molars grind food.grind food
- Write the answer. Molars
Check. Molars are large and flat. ✓
Method. Read the key idea in section 5.3.
- Read the key idea. Canines are pointed and tear food.canines
- Write the answer. canines
Check. Canines tear food. ✓
Method. Think about the outside of a tooth.
- Think about enamel. Enamel is the hard outer layer that protects the tooth.hard outer layer
- Decide. So the answer is yes.yes
- Write the answer. yes
Check. Enamel protects the inside of the tooth. ✓
Method. Add the incisors and the canines.
- Read the rows. There are 8 incisors and 4 canines at the front.8 and 4
- Add them. 8 plus 4 makes 12.12
- Write the answer. 12
Check. The 8 premolars and 12 molars are at the back. ✓
Method. Subtract the child total from the adult total.
- Read the totals. An adult has 32 teeth, and a child has 20.32 and 20
- Subtract. 32 minus 20 is 12.32 - 20 = 12
- Write the answer. 12
Check. Check: 20 plus 12 makes 32. ✓
Method. Think about a fair survey.
- Think about the survey. Each person should be asked the same question, in the same way.same question
- Write one thing. Keeping the question the same makes the results fair to compare.fair
- Write the answer. Accept any one thing, such as: ask every person the same question, and count in the same way.
Check. A fair survey keeps the method the same for everyone. ✓
Method. Think about how teeth change.
- Think about milk teeth. A child has milk teeth, which fall out.milk teeth
- Think about the adult teeth. The adult teeth grow in, and include the premolars and molars at the back.premolars
- Write the answer. Accept any sentence that says a child has milk teeth, which fall out and are replaced, and the adult teeth include more premolars and molars.
Check. Adults have more teeth than children. ✓