What type of injection is administered near the apex of a tooth?

The correct choice refers to an infiltration injection, which is specifically administered near the apex of a tooth. This method involves depositing anesthetic into the tissues around the roots of individual teeth, allowing for localized anesthesia. It provides numbness to the particular tooth and adjacent soft tissues, making it especially useful for procedures like fillings or crown preparations where only a small area needs to be anesthetized.

Infiltration injections are typically performed in the maxillary arch because the bone is less dense, allowing the anesthetic to diffuse effectively. It's a common technique for single-tooth anesthesia, facilitating dental procedures by ensuring patient comfort without affecting the entire quadrant or arch.

In contrast, other types of injections, such as nerve blocks, are used to anesthetize larger areas or multiple teeth, as they target major nerves supplying that region. Periodontal ligament injections involve placing the anesthetic directly into the periodontal ligament space of the tooth but are less commonly used than infiltration for routine dental work.