Babies drool, old men dribble, and some individuals spit when they talk; the rest of us would rather not be reminded that saliva exists; practicing dentists consider it a nuisance that must be sponged, evacuated, or dammed. Saliva has shown remarkable potential as a diagnostic fluid over the years, as numerous illness biomarkers may also be identified in entire saliva, in addition to blood and other bodily fluids. Saliva has been examined intensively as a potential diagnostic tool over the last decade due to its easy and non-invasive accessibility, as well as its richness of indicators such as genetic material and proteins. In this review, we'll look at some of the new ways saliva can be used as a diagnostic tool in paediatric dentistry, spanning the "omic" spectrum.