Cell-substratum interactions are of fundamental importance for the reaction of body tissues to surgically implanted foreign materials. In our study we investigated the influence of 2 microm wide microgrooves, with various depths (0.5-6 microm), on capsule formation around subcutaneous silicone implants, in an animal experiment. Silicone sheets with microtexture were glued around silicone tubes. These implants were placed subcutaneously in eight guinea pigs for 10 weeks. The implanted tubes were removed including all surrounding tissues, and processed for light microscopy and subsequent histomorphometrical evaluation. All removed implants were surrounded by a thin fibrous capsule, and it was observed that this capsule was separated from the implants by a thin, single layer of mono- and multinucleated phagocytotic cells. In histomorphometry no significant differences were seen in relation to the reaction towards the various textures. We conclude that microtextures do not have an effect on the morphological characteristics of capsule formation around silicone implants in soft tissue.