Comparison between textured silicone implants and those bonded with expanded polytetrafluoroethylene in rats

PURPOSE: Comparison of the inflammatory reaction promoted by textured silicone implants and that caused by the implant bonded with e-ptfe. METHODS: One-hundred and fifty rats were divided into three equal groups (control, silicone, and bonded e-ptfe). These groups were subdivided into five groups, according to the second operation, i.e., 7,30,60,90 and 180 days. Histology of the peri-implant tissue was analyzed by morphometry with blood count (neutrophils, lymphocytes, macrophages, fibroblasts and capillaries). RESULTS: Comparison of subgroups 7,30,60,90, 180 days: - neutrophils: silicone: > in subgroup 7 days; bonded e-ptfe: > in subgroups 7 and 30 days; - lymphocytes: silicone: > in subgroup 7 and 180 days; bonded e-ptfe: > in subgroup 180 days; - macrophages: silicone: > in subgroup 7 and 60 days; bonded e-ptfe: > in subgroup 7,30 and 60 days; - fibroblasts: silicone: > in subgroup 30 and 60 days;- vascular volume: silicone: in subgroup 7, 60 and 90 days; bonded e-ptfe: > in subgroup 7 days. Comparison of groups: neutrophils : 7 days: > in silicone and bonded e-ptfe; 30 days: > in bonded e-ptfe; - lymphocytes: - 7,30,90 and 180 days: in the control; macrophages: - 7,30 and 60 days: > in silicone & bonded e-ptfe; 180 days > in silicone; fibroblasts: - 7,30 and 90 days: > in silicone and bonded e-ptfe; 180 days: > in bonded e-ptfe; vascular volume 7,60,90 and 180 days: > in silicone and bonded e-ptfe; 30 days: > in bonded e-ptfe. CONCLUSIONS: The acute stage of the inflammatory response was more severe and irregular in the silicone implant; both the silicone implant and the silicone bonded with e-ptfe promoted chronic inflammatory reaction and weak foreign body inflammatory response. These reactions were greater in the silicone implant group.