A: Dental disease is a common feline illness. Common signs of dental disease are lethargy and depression, usually because your cat is experiencing pain and discomfort in the mouth. Other signs may include red and swollen gums, bad breath, weight loss, declining appetite and difficulty eating. Your cat’s diet plays a role in disease prevention, as does daily tooth brushing. Twice-a-year examinations are important for your veterinarian to evaluate the teeth. For more information, visit www.catwellness.org.