Tissue Reaction in Response to Augmentation of Soft Tissue Defects According to the Dermis Graft Materials in Rabbits

ABSTRACT

The augmentation of soft tissue defects is one of the critical problems in the oral and maxillofacial surgery. Various types of graft materials, both autologous and non-autologous, have been used for the augmentation of soft tissue in the facial region. However, it is not easy to choose an ideal material for soft tissue augmentation because each has its advantages and disadvantages. An ideal graft material should meet the following criteria it should not leave a scar at the area from which it was taken; should have less likelihood of causing infection; should feel natural after implanted; and should be not absorbed. Among the materials meeting these criteria, human dermis and artificial dermis are commonly used for clinical purposes. The present study was aimed to investigate and compare the resorption rate and the histological change following the use of the autologous dermis, the human homogenous dermis Alloderm(R), and the artificial dermis Terudermis(R) to reconstruct the soft tissue defect. Twenty mature rabbits of either sex, weighing about 2 kg, were used. Each rabbit was transplanted with the autologous dermis, Alloderm(R), and Terudermis(R) size 1 x 1-cm at the space between the external abdominal oblique muscle and the external abdominal oblique fascia. They were then divided into 4 groups (n=5 each) according to the time elapsed after the surgery 1, 2, 4, and 8 weeks. The resorption rate was calculated by measuring the volume change before and after the transplantation, and H-E stain was preformed to observe the histological changes. The resorption rate after 8 weeks was 21.5% for the autologous dermis, 16.0% Alloderm(R), and 36.4% Terudermis(R), suggesting that Alloderm(R) is the most stable while Terudermis(R) is the most unstable. In microscopic examinations, the autologous dermis graft was surrounded by inflammatory cells and showed foreign body reactions. The epidermal inclusion cyst was observed in the autologous dermis graft. Terudermis(R) and Alloderm(R) demonstrated neovascularization and the progressive growth of new fibroblast. The results suggest that Terudermis(R) and Alloderm(R) can be availably for substituting the autologous dermis.