Material and Methods
Patients were randomized in a 1:1 ratio into two groups: the ibuprofen–placebo (IP) group and the placebo–ibuprofen (PI) group. On postoperative Day (POD) 1, the IP group initiated ibuprofen administration, while the PI group started taking placebo. On POD 2, the IP group switched to using placebo, whereas the PI group switched to ibuprofen. From PODs 3–5, both groups were prescribed ibuprofen gargle. The primary endpoint was within‐subject visual analog scale (VAS) score before and 5 min after the first use of the ibuprofen or placebo gargle on PODs 1 and 2 (ΔVAS