 They determined that saliva testing for "H. pylori" antibodies “could be used reliably for screening dyspeptic patients in general practice.” That same year Tiwari, et al., examined the accuracy of testing saliva for "H. pylori" DNA and how well this correlated with presence of "H. pylori" detected via gastric biopsy.Based on their results, researchers concluded that saliva testing could serve as a reliable non-invasive detection method for "H. pylori" infection.A 2009 study conducted by Koss, et al., studied salivary biomarkers of periodontal disease; their findings revealed that three substances (peroxidase, hydroxyproline and calcium) were significantly increased in the saliva of patients with periodontitis.