Evaluation of Paste-Type Micronized Acellular Dermal Matrix for Soft Tissue Augmentation: Volumetric and Histological Assessment in a Mouse Model

Background A biological injectable material, paste-type micronized acellular dermal matrix (ADM), has been proven effective in wound healing by filling defects through tissue replacement. This study aimed to compare the efficacy of paste-type micronized ADM on soft tissue augmentation with that of the conventional fillers in animal experiments. Methods Two distinct paste-type micronized ADMs, which were mixed with distilled water (mADM) and gelatin (mADM?GEL), respectively, were compared with conventional fillers, hyaluronic acid (HA) and polymethyl methacrylate (COL+PMMA). Thus, four different types of fillers were each injected into the dorsum of nude mice to compare the volume retention and biocompatibility. During the 8-week experimental period, ultrasound and computed tomography (CT) images were obtained for volumetric analysis. Histological evaluation was performed using hematoxylin and eosin and CD 31 staining. Results According to the CT images at week 8, the mADM and mADM?GEL showed a higher volume persistence rate of 113.54% and 51.12%, compared with 85.09% and 17.65% for HA and COL+PMMA, respectively. The 2-week interval ultrasound images revealed that the mADM showed a volume increase in width rather than in height, and an increase in height for HA did not vary much. Histological analysis showed marked fibrous invasion and neovascularization with the mADM and mADM+GEL compared to that of the conventional fillers. Conclusions Paste-type micronized ADM showed soft tissue augmentation with similar effectiveness to that of conventional fillers. Therefore, paste-type micronized ADM has potential as an alternative material for a soft tissue filler in tissue replacement.