What is the primary role of the cementum on teeth?

The primary role of cementum is to anchor the tooth to the alveolar bone. Cementum is a mineralized tissue that covers the roots of teeth and helps secure them firmly within their sockets, thereby playing a crucial role in maintaining tooth stability and alignment during functional activities such as chewing. It provides an attachment point for the periodontal ligament, which connects the tooth to the surrounding bone and allows for slight movement of the tooth under pressure, ensuring that occlusion and bite force are balanced.

The other options do represent important functions in dental anatomy but do not accurately describe the role of cementum. For example, while enamel protects the tooth structure, cementum does not serve that purpose. Instead, the enamel's role is to shield the softer dentin and pulp from mechanical and thermal injury. Similarly, cementum does not directly facilitate tooth eruption; that process is primarily influenced by the growth of the alveolar bone and the developing tooth itself. Lastly, cementum does not support the oral mucosa, as that role is primarily fulfilled by the underlying connective tissues and structures of the oral cavity.