The clinical assessment of oral dryness is a significant predictor of salivary gland hypofunction.

Abstract

To compare subjective complaints of xerostomia and salivary gland dysfunction and a clinical assessment of oral dryness with an objective measurement of salivary gland dysfunction, in a group of UK patients attending a Dry Mouth Clinic. The aim of the study was to identify signs and symptoms that may be of predictive value for salivary gland hypofunction (SGH) in clinical practice. This prospective study investigated 214 patients who attended a Dry Mouth Clinic, held at Liverpool University Dental Hospital. Patients gave a history of xerostomia for a minimum of 6 months and were asked standardised questions to subjectively assess oral dysfunction. The oral mucosa was then clinically assessed for dryness and sialometry was performed. Unstimulated whole saliva flow rates (UFR) of < 0.2 ml min-1 were considered to be indicative of SGH. One or more symptoms of oral dysfunction were reported in 178 (83%) patients, in addition to xerostomia. The clinician diagnosed oral dryness in 105 patients. Objective evidence of SGH was found in 125 (58%) of patients. The clinicians' subjective assessment of oral dryness was indicative of a reduced UFR (P < 0.0001) and a significant predictor of an UFR < 0.2 ml min-1 using logistic regression analysis (odds ratio 9.6; 95% CI 4.8 and 19.3). The mean UFR of patients who reported symptoms of oral dysfunction was significantly lower than the mean UFR of patients who reported no oral dysfunction. Using logistic and multiple regression analyses, symptoms of oral dysfunction were not found to be significant predictors of either an UFR < 0.2 ml min-1 or a reduced UFR. The clinical assessment of oral dryness was a significant predictor of SGH, in this selected group of patients. Patients who complain of xerostomia may have additional symptoms of oral dysfunction indicative of a reduced UFR.