Title Chewing discs demonstrate significant diagnostic potential for xerostomia.
Clinical Question For healthy and patients with systemic conditions associated with dry mouth, is chewing time of specifically designed discs a viable screening modality for diagnosing xerostomia compared to sialometry?
Clinical Bottom Line In healthy and indisposed adult patients, chewing or dissolution time of specifically designed discs demonstrate significant diagnostic potential in primitive studies. The cross-sectional studies reviewed find positive correlations between disc dissolution times and salivary flow rates (sialometry gold standard). Both studies observed sensitivity and specificity values approaching 90%.
Best Evidence  
PubMed ID Author / Year Patient Group Study type
(level of evidence)
11961167Sanchez-Guerrero/2002Healthy, n=153 pts Sjogren’s Syn, n=30 Conn Tiss Dis, n=60 Comparison with Gold Standard
Key resultsThis cross-sectional study measured passive dissolution time for wheat-based wafers compared to the non-stimulated whole salivary flow gold standard. Success was indicated with a diagnostic ability to identify xerostomia. Wafers were placed on subject’s tongues; the time for saliva to dissolve the wafer was recorded. A Wafer dissolution time of 2.8 +/- 2.1 mins was found in the healthy cohort (n=152); 3.3 +/- 1.5 mins in the connective tissue disease cohort (n=60); and 9.2 +/- 3.9 mins in the Sjogren’s syndrome cohort (n=30). A correlation coefficient between the Wafer test and non-stimulated whole salivary flow was found to be -0.60 (95% CI -0.47, -0.71). The ROC curve-derived time providing optimal sensitivity and specificity was 4 minutes with a 92.9% sensitivity, 71.7% specificity, 31.7% positive predictive value, 98.6% negative predictive value and a likelihood ratio of 3.3 (95% CI 2.3, 4.6) to predict xerostomia. After “controlling for age, gender, temperature and relative humidity,” Sanchez-Guerrero et al determined a 4-minute dissolution time cutoff as the diagnostic threshold for patients experiencing salivary flow rates indicative of xerostomia.
19392963Madinier/2009Trial I: n=30 adults Trial II: n=30 elderly Comparison with Gold Standard
Key resultsThis cross sectional study compared time required to chew flour-based discs with stimulated salivary flow rate (SSFR, mL/min) in the diagnostic ability to identify hyposalivation (SSFR <1 mL/min). By utilizing a receiver operating characteristic (ROC) curve, a 40-second chewing time threshold enabled diagnosis of hyposalivation with a specificity of 1.00 and a specificity of 0.72. Accuracy of the tool was found to diagnose hyposalivation and mild hyposalivation (SSFR <1.5mL/min) with a sensitivity (95% CI) of 0.93 (0.77-0.99), a specificity (95% CI) of 0.88 (0.70-0.98), a positive predictive value (95% CI) of 0.90 (0.73-0.98), and a negative predictive value (95% CI) of 0.92 (0.74-0.99). A negative correlation was found between chewing times and sialometry with a Spearman coefficient of R=0.77 (P<.001).
Evidence Search 1.("xerostomia"[MeSH Terms] OR "xerostomia"[All Fields]) AND disc[All Fields] AND ("research design"[MeSH Terms] OR ("research"[All Fields] AND "design"[All Fields]) OR "research design"[All Fields] OR "test"[All Fields]) 2.wafer[All Fields] AND ("research design"[MeSH Terms] OR ("research"[All Fields] AND "design"[All Fields]) OR "research design"[All Fields] OR "test"[All Fields]) AND ("xerostomia"[MeSH Terms] OR "xerostomia"[All Fields] OR "hyposalivation"[All Fields])
Comments on
The Evidence
Validity: Results of the Wafer test confirm a significantly low positive predictive value of 31.7%; however, the test’s strength is noted in its strong negative predictive value (98.6%), enabling a provider to confidently discount xerostomia when chewing time exceeds 40 seconds. Perspective: Subjectivity is introduced into the methodology in both studies. Subjects were instructed to self-report chewing times before an observer evaluated physical confirmation. Further studies are suggested before a definite protocol is proposed, to include integration of a subjective component required to diagnose xerostomia. A diagnosis for xerostomia includes both quantatitive and qualitative factors.
Applicability The studies include a wide spectrum of diseases and demographics in design. Diagnostic discs are significantly affordable and easily implemented without compromise of time and complication. Natural ingredients offer minimal harm while serving as a pragmatic screening modality where a positive result would warrant subsequent gold standard investigation.
Specialty (Oral Medicine/Pathology/Radiology) (General Dentistry) (Periodontics) (Restorative Dentistry) (Dental Hygiene)
Keywords Xerostomia, diagnosis, hyposalivation, wafer, disc, specificity, sensitivity
ID# 2518
Date of submission 08/06/2013
E-mail passb@livemail.uthscsa.edu
Author Benjamin Pass
Co-author(s) Andrew Nguyen
Co-author(s) e-mail NguyenA9@livemail.uthscsa.edu
Faculty mentor James Piper, DDS
Faculty mentor e-mail james.piper@us.af.mil
Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)
None available
Comments and Evidence-Based Updates on the CAT
None available