Inflammations of the paranasal sinuses can be restricted to a single sinus or affect multiple sinuses. Acute and chronic infections can be either suppurative (pus-forming) or non-suppurative. Maxillary sinusitis is commonly caused by nasal infection or dental issues and presents with pain in the cheek or teeth. Chronic sinusitis is defined as long-standing infection where the mucosal changes may be irreversible. Management involves identifying and treating predisposing factors, providing drainage, and surgery in resistant cases.