Dogs need to get their teeth cleaned just like people. if there’s an infection around the teeth, it can make your dog’s mouth smell. Periodontal diseases are the most common cause of teeth infection that causes foul odor. It affects about 75% of dogs over the age of two years. Bacteria cause inflammation in the gums around the teeth. When oral hygiene is neglected, these bacteria in combination with food particles, thrive and deposit calculus on the teeth. This runs in a cycle where more bacterial growth causes more inflammation and calculus keeps depositing until this inflammation leads to the development of periodontal disease. This causes permanent changes in the supporting tissues of teeth which gives rise to deeper infections, pain, and eventually tooth loss. If left untreated, the infection can spread to distant organs such as the liver, kidneys, and heart. When treating periodontal disease, the goal is to restore the dental hygiene which is necessary to maintain oral health.