This chapter discusses antral wash and intranasal antrostomy, where antral wash is a surgical procedure in which a cannula is inserted into the maxillary antrum through inferior meatus. In proof puncture Lichtwitz antral trocar is entered into maxillary sinus through inferior meatus or canine fossa puncture. Intranasal antrostomy is a procedure in which maxillary antrum is opened through its medial wall for purpose of drainage and subsequent washes. In oroantral fistula proof puncture is done to confirm or treat the infection of maxillary sinus. Presence of malignant cells in the returning fluid confirms the malignancy, but its absence does not rule out the malignancy. It is not done in fracture maxilla as fluid may pass through fracture lines causing other complications. Direction of trocar should be backwards and laterally towards the outer canthus of same eye. Proof puncture through middle meatus is not done due to the fear of injury to orbit and reactionary oedema blocking the natural ostium.