@joh Hello, you should visit a dentist and get tested. Toothache while eating chocolate is also known as sugar sensitivity. Sugar sensitivity due to chocolate or any kind of sweets, and there’s a good chance you have some sort of damage to your teeth or gums. You can experience sensitivity for a number of reasons. It could be because of Loss of Enamel, tooth decay, gum disease. Visit your dentist and You can spot any potential underlying issues before they become major by seeing your dentist regularly. If your teeth hurt after eating sugar or chocolate, your dentist can help determine why and provide a course of treatment to decrease sensitivity. Thank You.