“…It has been proposed that the association between a specific microbial environment and a modified host response could take place during the development of aggressive periodontitis (Meng et al 2007; Zheng et al , 2007). Researchers have stated that LL‐37 has killing effect on Aggregatibacter actinomycetemcomitans (Pütsep et al , 2002, de Haar et al , 2006, Tanaka et al , 2000) which is an important periodontopathogen for aggressive periodontitis (Gronert et al , 2004; Sosroseno et al , 2008). It has also been stated that functional defects in polymorphonuclear leukocytes and monocytes may increase host susceptibility to tissue destruction in aggressive periodontitis (Liu et al , 2001; Gronert et al , 2004).…”