In conclusion, saliva is a promising diagnostic fluid for early diagnosis, prognosis, and posttherapy monitoring of various diseases due to its non-invasive nature, cost-effectiveness, and greater sensitivity and correlation with blood levels. Saliva contains a complex mixture of biomolecules that can provide a wealth of information for diagnostic purposes, making it an increasingly valuable tool for the diagnosis and monitoring of various medical conditions, including oral diseases. Salivary biomarkers can be used for early detection, diagnosis, and monitoring of disease progression, as well as predicting treatment response. Biosensing technologies have been developed to detect these biomarkers with enhanced sensitivity, selectivity, accuracy, and practicality, which can lead to better treatment outcomes and prevent further complications. Therefore, salivary diagnostics should be considered as an important clinical tool in regular screening and monitoring of patients.