Experimental study of autologous cartilage, acellular cadaveric dermis, lyophilized bovine pericardium, and irradiated bovine tendon: applicability to nasal tip plasty.

The purpose of this study was to compare the volumetric and histologic changes of the acellular cadaveric dermis, lyophilized bovine pericardium, irradiated bovine tendon, and autologous cartilage transplanted subcutaneously in the rats. Four different kinds of implants were placed in subcutaneous pockets of the dorsum of 40 Wister rats. The implants with the subcutaneous pockets were retrieved in the first, fourth, eighth, and 12th weeks after implantation. The size and histologic change of each implant were observed. The xiphoid cartilage showed the peak survival (71.0%, P = 0.247) on the 12th week, but part of the cartilage was absorbed irregularly and its shape changed unpredictably. The lyophilized bovine pericardium had a high survival rate as well (64.4%, P = 0.016). However, the size decreased significantly in the first through 12th weeks. A survival of acellular cadaveric dermis was lower (38.8%, P = 0.036) than the cartilage and pericardium, but it sustained the structure for 12 weeks and changed peripherally into the neocollagen. Irradiated bovine tendon disclosed the lowest survival rate (31.4%, P = 0.008). The structure was gradually distorted and replaced entirely by neocollagen in the 12th week after implantation. Autologous cartilage is the best choice for soft tissue and nasal tip augmentation. Although other implants than the cartilage showed significant diminution of its volume in 12 weeks, lyophilized bovine pericardium could be the next substitute to the cartilage in soft tissue augmentation.