MPO and periodontitis: The present study therefore aimed to compare potential mouthrinse periodontitis biomarkers (the aMMP-8 POCT, the aMMP-8 RFU activity assay, and total MMP-8) and related biomarkers (MPO, PMN elastase, calprotectin, and interleukin-6) in periodontal disease diagnosis and in monitoring the effects of nonsurgical anti-infective periodontal therapy.