Salivomics: An Upcoming noninvasive diagnostics – A narrative review

Saliva is increasingly being recognized as a bodily fluid that can be used for quick diagnosis and to assess prognosis in a few systemic conditions. The major advantage of using saliva as a point-of-care bodily fluid is its noninvasive collection. Salivaomics, an emerging branch of diagnostic pathology, is gaining increasing importance in both the dental and medical fields. This narrative review examines the intricacies of using saliva as a diagnostic marker and the importance of salivaomics across different fields. The objectives of the study are (a) to identify salivary biomarkers in disease conditions, (b) to summarize the tools available for saliva collection, storage, and transportation, and (c) to identify techniques used for salivary biomarker processing for the assessment of clinical outcomes. The present review was conducted as per the “Preferred Reporting Items for the Systematic Reviews and Meta-Analysis” or PRISMA guidelines. A) Study eligibility criteria: The research questions were based on salivaomics, saliva collection, sample preparation and transportation, storage, and different techniques used for the saliva analysis. Various articles on the challenges and future of salivary diagnostics for oral cancer were also reviewed, along with those on other systemic conditions. B) Synthesis method: Different online search engines and databases such as Scopus, PubMed, Google Scholar, Cochrane Library, and Web of Science. Medical Subject Headings (MeSH) search terminologies used were “saliva,” “head and neck lesions,” “oral cancer,” “oral neoplasms,” “premalignancies,” “potentially malignant disorders” “biomarkers,” “diagnosis,” “saliva collection methods,” “saliva sample preparation,” “salivary transportation,” “method of saliva storage,” “techniques for analysis of saliva,” “current challenges in saliva diagnostics” and “future challenges.” Boolean operators used were “AND” or “OR” for the article search. The data extraction involved collecting information on objectives, methodology, results, and conclusions from the articles selected for the review. A total of 100 journal publications were identified following a literature search, oof which 26 articles were finalized for review. The published articles demonstrate the usefulness of saliva for diagnosis and follow-up in patients undergoing long-term follow-up or treatment protocols. Limitations of this paper include a lack of sufficient publications based on real-time quantitative data suggestive of salivaomics in patient management. In conclusion, this narrative review paper covers various techniques for collecting saliva samples, their methods of transportation and storage, and the analytical tools and biomarkers currently being studied for identifying different diseases and conditions affecting the body. Hence, one can utilize salivary biomarkers to assess patients for different clinical conditions and to customize treatment plans.