However, when comparing periodontitis vs health groups, the values of the aforementioned biomarker relations were significantly higher than the single biomarkers, with a magnitude up to 33.69-fold for MMP-8/TIMP-1; 27.90-fold for MMP-9/TIMP-1; 31.39-fold for (MMP-8 + MMP-9)/TIMP-1; and 8.72-fold for MMP-8 + MMP-9 (Fig. 1, Table 3). This evidence concerns the gene MMP9 and periodontitis.