The periodontium is the specialized tissues that both surround and support the teeth, maintaining them in the maxillary and mandibular bones.

Periodontics is the dental specialty that relates specifically to the care and maintenance of these tissues. It provides the support necessary to maintain teeth in function. It consists of four principal components, namely: Gingiva, periodontal ligament (PDL), cementum, alveolar bone proper.

Each of these components is distinct in location, architecture, and biochemical properties, which adapt during the life of the structure. For example, as teeth respond to forces or migrate medially, bone resorbs on the pressure side and is added on the tension side. Cementum similarly adapts to wear on the occlusal surfaces of the teeth by apical deposition.

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