Like the nuggets in chunky peanut butter, nuts can be pretty hard. Young, strong teeth may be up to the challenge, but teeth with fillings or ones that have undergone root canal treatment are less than 100 percent. Biting down on a nut at the wrong angle could cause a tooth to crack, break, chip or lose a filling. Although it would be nice to say nuts are the only culprits, even pits found in common fruits like peaches and cherries can be hard on teeth when encountered unexpectedly. Before you bite down with gusto, know what you're eating and use extra caution if any of your teeth are compromised. That cashew may look like a delicious morsel, but it could come with a hefty price tag if you have to spend an afternoon in a dentist's chair after indulging.