Final answer:
NSAIDs like aspirin, ibuprofen, and naproxen reduce pain through anti-inflammatory actions by inhibiting COX enzymes, but they do not have an anesthetic effect in periodontal therapy since they do not block nerve impulse transmission like local anesthetics.
Step-by-step explanation:
Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, ibuprofen, and naproxen, have mechanisms that involve the inhibition of prostaglandin synthesis, thus reducing inflammation and pain. These drugs work by blocking the action of cyclooxygenase (COX) enzymes, which are essential in the conversion of arachidonic acid into prostaglandins. Although NSAIDs are effective in reducing pain associated with inflammation, they do not have an anesthetic effect in the traditional sense, as they do not block nerve impulse transmission as local anesthetics do. Local anesthetics work by altering ion movement across the cell membrane, thus preventing sensation of pain. Therefore, while NSAIDs can reduce discomfort during periodontal therapy due to their anti-inflammatory action, they cannot replace local anesthetics that cause numbing by blocking nerve impulses.