Role and Relevance of Warm Saline Mouth Rinses in Contemporary Dental Practice: A Narrative Review

Warm saline mouth rinsing is one of the oldest and most widely practiced adjuncts in dentistry; however, its evidence base has been substantiated only recently, both mechanistically and clinically. In vitro studies have shown that short-term rinsing with hypertonic sodium chloride promotes gingival fibroblast migration and extracellular matrix protein expression via a chloride-dependent pathway, offering a cellular explanation for its long-observed wound-healing benefits. Clinically, saline rinsing has consistently been shown to be effective in reducing alveolar osteitis following tooth extraction, with benefits comparable to those of several antimicrobial rinses, and randomized evidence supports its use as a practical, postoperative default. In oncology, saline is part of standard basic oral care during radiotherapy and chemotherapy, although systematic reviews have found evidence for its independent efficacy against oral mucositis to be inadequate or conflicting, with several herbal and iodine-based comparators showing comparable or superior symptomatic benefits. In critical care, saline-based oral hygiene protocols show a favorable mortality and microbial diversity profile relative to chlorhexidine in mechanically ventilated patients, despite chlorhexidine's superior effect on ventilator-associated pneumonia incidence. Comparative trials across periodontal and antimicrobial contexts generally position saline below chlorhexidine and several herbal formulations for plaque and gingival index outcomes, although its safety profile makes it a suitable substitute for patients intolerant to chlorhexidine. Limitations include a thin mechanistic evidence base, potential effects on enamel surface hardness with prolonged use, and reliance on small and heterogeneous studies. For dental practitioners, warm saline mouth rinsing remains a safe, low-cost, and evidence-based adjunct across surgical, periodontal, oncological, and critical care contexts and is best positioned as a first-line or complementary rinse rather than a substitute for targeted antimicrobial therapy, where high-potency plaque or pathogen control is required.