Salivary duct strictures: nature and incidence in benign salivary obstruction

The aim of this study was to establish the incidence and character of salivary duct strictures by carrying out a 10 year retrospective review. Salivary gland obstruction is most commonly caused either by salivary calculi or duct strictures. These strictures or stenoses develop secondarily to inflammation in the duct wall and may be single or multiple.

All reports of sialographic examinations performed on patients referred to the Dental Radiology Department in a London Dental Hospital between 1995 and 2004 were reviewed and those patients with symptoms of salivary obstruction identified. In total, 1362 sialograms using the conventional hand injection technique with water-soluble contrast media were performed on 1349 patients with obstructive symptoms during the 10-year period.

Of the 1362 sialograms performed, the reports revealed that 877 (64.4%) showed evidence of benign intraductal obstruction. The remaining 485 (35.6%) were normal. 642 of the cases (73.2%) revealing obstruction were reported to be due to salivary calculi, 198 due to duct strictures (22.6%) and the remaining 37 (4.2%) were considered to be due to mucous plugs. Detailed analysis of the patients with strictures showed they were more common in women with a mean age of 52 years. Single strictures were evident in 66.7% of cases while 33.3% showed multiple stenoses. Strictures were more common in the parotid duct (75.3%). 7% of patients presented with bilateral stenoses.

This is the largest review of duct strictures to be reported. It has shown that ductal stricture formation accounts for almost 25% of cases of benign salivary obstruction and appears to have been an under-recognized condition. Strictures more commonly affect parotid ducts and are typically found in the fourth, fifth or sixth decades, particularly in women.