The number of studies discussed each topic include 14 studies about infection with biofilm-producing bacteria and SSIs; six studies about radiation therapy and previous fibrosis; nine studies about antibiotics and irrigations; six studies about implant surface, size, and placement; three studies about acellular dermal matrix (ADM); three studies about leukotriene antagonists (LTE); one study about toll-like receptor 4; and one study about Thy1(CD90) expression. The suggested risk factors and preventions for CC are summarized in Table 2. The gene discussed is THY1; the disease is infection.