Background: Gastric and mucosal changes were studied when different synthetic materials were used for gastric banding. Methods: 60 Wistar-Albino rats (weight 200-250 g, age 12 weeks) were classified into 5 groups. Gastric banding was carried out with different materials: group 1 - polytetrafluoroethylene (PTFE), group 2 - polythylene (PE), group 3 - polypropylene (PP), group 4 - silicone; and group 5 - controls. Histopathological examination of proximal and distal gastric mucosa and esophagus were evaluated for foreign body reaction, lymphocytic infiltration, neutrophil infiltration, gastric wall invasion, and gastroesophageal reflux, Results: PE and PP caused a much more severe foreign body reaction that PTFE and silicone. Lymphocytic infiltration (chronic inflammation) was not significantly different between PP, PE, and PTFE, and was present in 80% of rats with these materials (P>0.05); in the silicone group, lymphocytic reaction was minimal. There was no neutrophilic infiltration in the silicone group (P=0.001), but this sign of acute inflammation was present in the other groups. However, the neutrophilic infiltration showed no difference between PE, PTFE and PR PP, PE and PTFE migrated into the gastric wall at similar rates (no significant difference, P>0.05); in the silicone group, however, intragastric migration was not observed. With regard to gastroesophageal reflux, no significant difference was found between all the groups (P>0.05). In all groups, no histopathologic change was observed in the gastric mucosa proximal and distal to the bands. Conclusion: Silicone was the ideal material for banding, because it had good tissue adaptation and caused no inflammatory response.