Use of the modified Schirmer test to measure salivary gland hypofunction/hyposalivation: Systematic review and meta-analysis.

Although dry mouth is a relatively common condition, salivary flow is not routinely measured in dental clinical practice. Moreover, existing data regarding the use of the modified Schirmer test (MST) for the screening of dry mouth has not been summarized. This systematic review and meta-analysis, conducted in accordance with the PRISMA guidelines, aimed to determine whether the modified Schirmer test can be used to identify dry mouth. The databases of PubMed, Scopus, ScienceDirect, and CENTRAL (CRD42023393843) were systematically searched to retrieve articles published until 9th November 2023. Among the 343 original articles retrieved, six met the inclusion criteria. A total of 1150 patients, comprising 710 (61.7%) women and 440 (38.3%) men (mean age, 47.1 ± 7.3 years), were included. The meta-analysis revealed a weak correlation coefficient of r ¯ $\bar{r}$  = 0.42 (95% Cl: 0.29-0.55) between MST and the unstimulated salivary flow rate. Therefore, while the MST might offer a simple and accessible alternative for initial screening in the future, especially in non-specialized settings, its variability in sensitivity and specificity, along with an actual lack of standardization, necessitates cautious interpretation. Further studies are necessary before recommending the test in clinical routine.

Using the modified Schirmer test for dry mouth assessment: A cross-sectional study.

This study aimed to establish whether the modified Schirmer test could serve as a diagnostic tool for dry mouth, that is, whether it could reliably measure salivary film at selected locations within the oral cavity, and to identify levels of sensitivity/specificity and determine reference values. Therefore, a cross-sectional study (N = 120, mean age 63.5 [SD 13.9] years) was performed. The test was used at five locations (hard palate; buccal mucosa in molar region at 4 mm above occlusal plane; anterior tongue; lower lip; mouth floor), and results were recorded after 1, 2 and 3 min. A statistically significant discriminatory ability of the Schirmer test for the unstimulated salivary flow rates could be shown for the palate (at 3 min), buccal mucosa (at 1 min), mouth floor (at 1 min), and tongue (at 2 and 3 min) (areas under the curve 0.64-0.68), with individual sensitivity/specificity values depending on test location/time points. Thus, the modified Schirmer test has potential to become a simple and reproducible instrument for the detection of dry mouth based on low unstimulated salivary flow rates in dentistry and especially outreach care. Care must be taken concerning intraoral test location and measurement time.