Which of the following statements correctly lists the components of the periodontium?

• A. All of the above
• B. PDL
• C. Ccementum
• D. Alveolar bone

Answer: (A)

The periodontium consists of the tissues that attach and support a tooth: cementum, the periodontal ligament (PDL), and the alveolar bone. Cementum provides a surface for the PDL to attach to the tooth root; the PDL anchors the tooth to the bone and cushions lateral and vertical forces; and the alveolar bone forms the socket that houses the tooth. Because each of these elements is a fundamental part of the periodontium, a statement that lists all of them together accurately reflects its components. Therefore, the option that includes all of the above is the best choice. (Gingiva is sometimes discussed as part of surrounding tissues, but the three core components shown are the primary periodontium elements.)