Generally, there are two categories of dental events. Dental accidents (broken teeth) and dental illnesses (periodontal disease, feline tooth resorption, or gingivitis/stomatitis). Considering that periodontal disease is the most frequent disease diagnosed by veterinarians in pets (especially dogs), it should be covered. Feline tooth resorption and gingivitis/stomatitis can be very expensive to treat. So try to get insurance that covers both dental accidents and illness.