OBJECTIVE: To compare the utility of porcine renal capsule matrix (RCM) with porcine small intestinal mucosa (SIS) in a rat full-thickness skin wound model. METHOD: Groups of rats had surgically-created wounds filled with either SIS or RCM. On each rat a contralateral wound was left unfilled (RCM-U or SIS-U).Wound diameter was measured 3, 7, 12, 17, 26 and 30 days after creation.Wound sites sampled 3, 7, 14, 28, 42 and 56 days after wound creation were numerically graded for degree of histologic change and for collagen content, based on intensity of trichrome staining. RESULTS: Wounds in all groups rapidly contracted to less than 50% of the original diameter within 12 days.There were no differences in wound diameter between RCM- and SIS-treated wounds at any time point, but these wounds had significantly greater (p < 0.001) diameters than their unfilled counterparts on days 7, 12 and 17. There were no differences in histologic scores or trichrome-staining scores between RCM- and SIS-treated wounds and their unfilled counterparts at any time point, except for a greater (p < 0.05) histologic score in SIS-treated wounds compared with unfilled controls on day 14. In both treatment groups an acute inflammatory response at the wound site was soon replaced by an influx of macrophages and fibroblasts. CONCLUSION: The results show that RCM is equivalent to SIS for the treatment of full-thickness wounds and that these materials may enhance wound healing in terms of wound-tissue collagenisation and maturation.These materials therefore merit further study in other wound-care models.