IADR Position and Policy Statement on Salivary Biology and Diagnostics
The International Association for Dental, Oral, and Craniofacial Research (IADR) recognizes saliva as an essential biological fluid in both oral and systemic health and its fundamental role in maintaining key physiological functions within the oral cavity. IADR also supports the use of saliva for diagnostics, health and disease status monitoring, and evaluating therapeutic outcomes. Despite extensive evidence of its importance, salivary biology and diagnostics remain underutilized in clinical dentistry, underrepresented in translational research, and insufficiently integrated into public health frameworks1. Moreover, alterations in salivary quantity and/or quality (salivary gland dysfunction) significantly increase the risk of oral diseases, and contribute to compromised nutrition and quality of life2,3,4. Yet, there is no consensus on reliable standardized clinical tests for assessing salivary gland function, neither efficient evidence-based treatments. This policy statement calls for routine evaluation of salivary function in daily clinical practice and for the development and validation of practical tools that enable early detection of salivary alterations and support timely preventive or therapeutic interventions. It is intended primarily as a resource for clinicians and researchers and will also inform industry stakeholders and policymakers - ultimately benefiting patients.
The functions of saliva and the impact of salivary gland dysfunction on oral health
Saliva forms a protective and immunological barrier over the oral mucosa and teeth, shielding tissues from environmental insults, aiding wound healing, providing the first line of defense against pathogens, and preserving tissue integrity5-8. Xerostomia is the subjective sensation of dry mouth, and this symptom is often associated with salivary gland dysfunction however it can also be present in patients with normal salivary flow rates9. Hyposalivation is a term based on objective measures of the salivary flow rates, where the flow rates are significantly lower than the generally accepted normal reference values10,11. Both the quantity (flow) of saliva and its composition (quality) play an important role in preventing dental caries12, oral infections13, and erosive tooth wear14, while also supporting essential functions such as lubrication, protection of hard and soft tissues, clearance, pH buffering, initiation of digestion, and facilitation of swallowing speech, and taste3. Saliva regulates oral microbiome and biofilm formation15-21 as well as promoting enamel remineralization22. Salivary quantity and quality also influence the longevity of dental restorations. Thus, in patients with hyposalivation of different etiologies, the survival time of dental fillings is significantly lower than in patients without xerostomia and normal salivary gland function23.
The prevalence of hyposalivation and xerostomia is increasing24-26 particularly among individuals affected by multiple diseases, polypharmacy and certain medications27,28. Medication-induced salivary gland dysfunction and xerostomia, associated with several drug categories, affects up to 30% of patients taking at least one medication28. Emerging evidence also links impaired salivary function to consumption of conventional cigarettes and e-cigarettes29, recreational drug use30,31, and a broader range of commonly prescribed and over-the-counter medications than previously recognized32. Lifestyle factors further contribute to salivary gland dysfunction across all age groups. Despite its growing prevalence, the condition is often underdiagnosed and undertreated, particularly among older adults and patients with chronic diseases24,33. Left unaddressed, salivary gland dysfunction undermines quality of life and increases the risk of oral diseases and preventable complications.
To recognize and manage salivary gland dysfunction, early detection is essential32. This underscores the need for diagnostic tools that can identify risks at an initial stage and guide preventive care. Validated testing of xerostomia and salivary gland function offers significant potential to pinpoint high-risk patients, support personalized prevention, and enable truly individualized treatment34 Furthermore, incorporating assessment into the first dental appointment for all patients would allow clinicians to establish a personalized baseline before xerostomia and salivary gland dysfunction appear35,36. Such baseline testing enables the early detection of subtle declines in salivary gland function and facilitates more accurate and reliable monitoring of salivary flow rates over time. It also allows for salivary gland dysfunction to be diagnosed against personalized parameters, rather than relying solely on broad and heterogeneous reference values37. Furthermore, there is an urgent need to develop standardized and comparable measurements of salivary and glandular function across populations, communities, and countries. Research initiatives should be promoted to generate harmonized datasets that incorporate age, systemic health conditions, and diverse national and ethnic backgrounds. Such globally comparable data are essential to strengthen epidemiological surveillance, improve diagnostic accuracy, and inform public health policies related to salivary gland dysfunction and oral health.
In clinical practice, care for patients with xerostomia and salivary gland dysfunction is typically limited to those in advanced stages of disease, such as patients with Sjögren’s disease or patients with radiotherapy-associated hyposalivation38,39. However, little is known about the problems that may arise from more subtle reductions in saliva quantity, and quality. Implementing analysis of saliva quantity and quality into clinical practice will support a more integrated, preventive care model - offering significant benefits for patients' oral and overall health and quality of life. This approach is also aligned with public health priorities and the evolving landscape of dental care delivery.
Saliva as a versatile biological fluid
Saliva is often described as the “mirror of the body”, frequently serving as an early warning sign of systemic disease or change in physical condition40. It has emerged as a promising diagnostic tool, offering insights into disease detection, progression, and prognosis and monitoring results of therapeutic interventions41 Thus, saliva provides a window into both oral and systemic health, due to its diverse components, including nucleic acids (DNA, mRNA, microRNA), epigenetics, proteins, metabolites, and a complex microbial community42-48. Beyond its biological complexity, saliva offers practical advantages: collection is simple, non-invasive, and inexpensive49. These characteristics make it an attractive tool for biomedical research, precision medicine, and routine health monitoring, with the capacity to deliver disease-specific biomarkers that support tailored diagnostic and therapeutic approaches.
Beyond its application in dentistry, saliva has proven diagnostic capabilities for diagnosing systemic and infectious diseases, including those caused by SARS-CoV-241,50, HIV51, immunoinflammatory responses8,52, and certain cancers53,54. Its utility during the COVID-19 pandemic demonstrated the scalability of salivary diagnostics55, reinforcing the need for stronger translational research and clinical integration. Despite this, stakeholder engagement and investment in salivary research remain limited, and there is currently no global policy guidance on its application.
Policy Statement
The IADR recognizes that advancing salivary biology and diagnostics should be aligned with global health priorities, particularly in promoting prevention and personalization of care. IADR therefore recommends:
- Recognizing salivary gland dysfunction and xerostomia as a public health concern and priority with implications for quality of life, oral and systemic health;
- Promoting the routine integration of evidence-based diagnosis and management of salivary gland dysfunction and xerostomia into oral care and advocate for their inclusion across public and private health systems through appropriate incentives, reimbursement mechanisms, and policy frameworks that ensure access, implementation, and sustainability.
- Strengthening the education and awareness of oral healthcare professionals and patients in salivary biology, as well as the diagnosis and therapeutic approaches of salivary gland dysfunction and xerostomia;
- Developing and validating clinical trials and evidence-based clinical guidelines to standardize protocols for the assessment of salivary gland function and to define effective, standardized therapeutic approaches for glandular and salivary gland functional disorders;
- Promoting interdisciplinary collaboration among academia, clinicians, patients, policymakers, and industry stakeholders to accelerate translational salivary gland research and implementation of valid salivary tests and treatment for dysfunctions.
IADR calls for coordinated global efforts to advance clinically relevant studies that address the significant impact of salivary gland dysfunction and xerostomia on quality of life and oral health, and efficient treatments for that. In parallel, it emphasizes the need for research that bridges basic scientific discoveries of systemic disease biomarkers toward their translation into clinical practice, ensuring that salivary diagnostics evolve into cost-effective and practical tools that can be widely applied.
Adopted 2026
