Periodontology or periodontics (from Ancient Greek περί, – 'around'; and ὀδούς, – 'tooth', genitive ὀδόντος, ) is the specialty of dentistry that studies supporting structures of teeth, as well as diseases and conditions that affect them. The supporting tissues are known as the periodontium, which includes the gingiva (gums), alveolar bone, cementum, and the periodontal ligament. A periodontist is a dentist that specializes in the prevention, diagnosis and treatment of periodontal disease and in the placement of dental implants.
The term periodontium is used to describe the group of structures that directly surround, support and protect the teeth. The periodontium is composed largely of the gingival tissue and the supporting bone.
Normal gingiva may range in color from light coral pink to heavily pigmented. The soft tissues and connective fibres that cover and protect the underlying cementum, periodontal ligament and alveolar bone are known as the gingivae. The gingivae are categorized into three anatomical groups: the free, attached and the interdental gingiva. Each of the gingival groups are considered biologically different; however, they are all specifically designed to help protect against mechanical and bacterial destruction.
The tissues that sit above the alveolar bone crest are considered the free gingiva. In healthy periodontium, the gingival margin is the fibrous tissue that encompasses the cemento-enamel junction, a line around the circumference of the tooth where the enamel surface of the crown meets the outer cementum layer of the root. A natural space called the gingival sulcus lies apically to the gingival margin, between the tooth and the free gingiva. A non-diseased, healthy gingival sulcus is typically 0.5-3mm in depth, however, this measurement can increase in the presence of periodontal disease. The gingival sulcus is lined by a non-keratinised layer called the oral sulcular epithelium; it begins at the gingival margin and ends at the base of the sulcus where the junctional epithelium and attached gingiva begins.
