VCAM1 and periodontal disorder: None of the genes of PLCG2, ALOX5, LTAH4, VCAM1, PLA2G2A and PLA2G10 showed statistically significant differential expressions when the study groups were modified into patients with periodontal disease and implant rejection versus patients without periodontal disease and with positive evolutions of their implants (PD+IR+ vs. PD-IR-).