Your teeth were never supposed to rot
Pretty much every person today by the age of 25 year has several teeth with fillings. I actually knew few people who already lost a tooth by that time (i.e. depulped tooth, refused to put a crown, tooth cracked).
It’s astonishing that galley slaves and other malnutritioned people actually had no problem with teeth. Yeah, they did not live long, but what I want to emphasize is that there is nothing forcing you to have cavities in teeth. It is also well known that dental caries epidemic started approximately the same time as sedentary agriculture.