35 patients who met the inclusion criteria were divided into surgical groups. Patients with indications for upper jaw surgery were divided into Le Fort I operation, patients with lower jaw surgery were divided into Sagittal Split Ramus operation, and double jaw surgery groups. Localized taste tests and whole-mouth taste tests were applied to the patients.

Gustatory functions were evaluated by administering localized taste tests and whole mouth taste tests preoperatively and at postoperative 1st, 3rd, and 6th months.

Patients who underwent Le Fort I osteotomy, Sagittal Split Ramus Osteotomy, and Bimaxillary Surgeries were asked to identify the quality of 4 basic taste modalities preoperatively and at postoperative 1st, 3rd, and 6th months by administering whole mouth taste tests. In the whole mouth taste test, one ml of the specific solution was drawn into the syringe and sprayed into the mouth of the patient circularly. After each administration, patients spat out the solutions and reported whether they perceived any taste and, if so, which taste it was.

The solutions were administered in increasing concentrations, starting from the lowest concentration up to the highest concentration until the patient perceived any taste. The lowest concentration at which the patient correctly perceived the administered taste was defined as the "taste recognition threshold. Taste recognition threshold is the primer outcome for whole-mouth taste tests.

The patients were instructed to focus on the perceived taste without closing their mouths and asked to identify the taste and rate the intensity of the taste using a scale ranging between 0 'no taste' and 9 'strongest taste', after each administration. Taste intensity rating is the primer outcome for localized taste tests.