Comparable Effectiveness of Novel and Commercial Saliva Substitute Gels in Dental Patients Experiencing Xerostomia: A Randomized, Double-Blind Crossover Trial

Saliva substitutes are the standard treatment for dry mouth. This study aimed to evaluate the clinical effectiveness of a novel artificial saliva gel (RSU gel) compared with a commercial product (GC Dry Mouth Gel^®). A randomized, double-blind, two-phase crossover clinical trial was conducted with 37 participants with xerostomia. In the short-term phase, oral wetness, xerostomia scores, and clinical score of oral dryness (CSOD) were assessed up to 60 min after a single gel application. In the short-term repeated-use phase, each gel was applied 4 times daily for 14 days, separated by a 14-day washout period. The same parameters, including patient satisfaction and adverse events, were re-evaluated. Data were analyzed using generalized linear mixed models and generalized estimating equations. Both the RSU and GC Dry Mouth Gel^® significantly improved oral wetness immediately after a single application. No significant difference was observed for the RSU gel relative to the GC Dry Mouth Gel^® for oral wetness (OR = 1.01, 95% CI 0.98, 1.04, <i>p</i> = 0.248), xerostomia score (OR = 1.10, 95% CI 0.42, 2.88, <i>p</i> = 0.661), or CSOD (OR = 0.95, 95% CI 0.58, 1.55, <i>p</i> = 0.765) at 60 min. After 14 days of use, oral wetness increased significantly in both groups (2.94%, 95% CI 0.30%, 5.76%, <i>p</i> = 0.030) and did not differ significantly between the two products (<i>p</i> = 0.110). The xerostomia scores and CSOD also significantly improved, independent of product type (OR = 7.21, 95% CI 2.56, 20.34, <i>p</i> < 0.001, and OR = 2.82, 95% CI 1.50, 5.32, <i>p</i> = 0.001, respectively). The participants reported high satisfaction and acceptable taste, and no adverse effects were detected in those using the RSU gel throughout the study. Its lower cost and local availability make it a practical option for xerostomia management, particularly in populations with limited access to commercial saliva substitutes.