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tooth decay; decayed tooth; dental cavity; dental caries
甘いものを食べすぎると虫歯になりやすい。
If you eat too many sweets, you're likely to get cavities.
定期的に歯医者に行って虫歯をチェックする。
I go to the dentist regularly to check for cavities.
虫歯の治療はできるだけ早い方がいい。
It's better to treat cavities as soon as possible.