This is the dental discipline concerned with the prevention and treatment of diseases and injuries to the supporting structures of the tooth. These supporting structures are the gums (gingivae), the jaw bones (alveolar bone) and the ligaments (periodontal ligaments) which ensure the attachment of the tooth to the bone. A dental professional who specifically carries out periodontal treatment is called a periodontist and the most commonly treated condition is gum disease (periodontal disease).