Meaning: Teeth that are healthy are not likely to break or get cavities.
Choice of Words: Healthy: in good condition; Teeth: hard white parts in your mouth; Strong: able to resist breaking or bending
Alternative Expressions
Teeth that are healthy are strong.
Meaning: This sentence has the same meaning as the first sentence, but it is more specific about the teeth that are being talked about.
Choice of Words: This sentence uses the phrase "teeth that are healthy" to describe the teeth that are being talked about. This is a more specific way to say "healthy teeth" and makes it clear that the sentence is about teeth that are in good condition.
If your teeth are healthy, they are strong.
Meaning: This sentence has the same meaning as the first two sentences, but it emphasizes that the health of the teeth is the cause of their strength.
Choice of Words: This sentence uses the word "if" to show that the condition of the teeth (being healthy) is the reason for the result (being strong).