CASP3 and periodontitis: Increased expression, protein, and activity levels of CASP3 and CASP9 have been found in gingival samples from sites of periodontitis as compared to healthy sites [44,45,46,47], which is in accordance with our study, which demonstrated increased CASP3 and CASP9 levels at transcriptional and protein level in gingiva from periodontitis patients.