HSPD1 and periodontitis: After taking into account age, sex, smoking, and number of teeth, A. actinomycetemcomitans and P. gingivalis IgG, Hsp65-IgA, oxLDL-IgG, and -IgM antibody levels were directly associated, whereas Hsp60-IgG2 antibody levels were inversely associated with periodontitis.