: Salivary duct stenoses account for approximately 15–25% of salivary gland obstructions. A well-recognized classification criterion for these stenoses has yet to be established. The present study aims to classify and characterize salivary duct stenoses based on sialography and sialendoscopy.

: The sialograms and endoscopic findings in 307 patients presenting with primary salivary duct stenosis were respectively reviewed. The location, grade of luminal narrowing, length, and number of the stenoses were assessed, and stenosis severity of each gland was categorized.

: Among 518 parotid glands (PGs) and 71 submandibular glands (SMGs) affected, stenosis severity was graded as mild in 11(1.9%), moderate in 283 (48.0%), severe I in 32 (5.4%), severe II in 98 (16.6%), and severe III in 165 (28.0%) of the glands. 89.6% of cases exhibited stenosis in bilateral homonymic glands. Of the 694 stenoses totally found, 22.0% were located in the distal, 23.1% in the distal-middle, 14.1% in the middle, 1.0% in the mid-proximal, 9.8% in the proximal, and 30.0% in the distal-middle-proximal segment. Stenosis severity was significantly higher in females than in males. A linear positive correlation was observed between age and stenosis severity. Significant differences were found in the luminal narrowing grade and location among stenoses of different lengths, as well as in the location, length, and luminal narrowing grade between stenoses of PGs and SMGs.

: A five-grade classification of salivary duct stenosis was proposed based on sialography and sialendoscopy, with a hope to provide a reference for treatment plan and prognosis evaluation.