Comparison of autogenous cartilage, acellular dermis, and solvent-dehydrated pericardium for the prevention and correction of dorsal nasal irregularities: an experimental study.

Background: Numerous materials have been used for the correction and prevention of dorsal nasal irregularities. Experimental and clinical studies have been useful but have provided insufficient results for several reasons, including the impossibility of obtaining pathologic specimens from aesthetic patients and imprecise experimental models. In this study, an experimental model for rhinoplasty is used for the comparative evaluation of solvent-dehydrated pericardium, acellular dermal matrix, and autogenous ear cartilage as onlay grafts for the prevention and correction of nasal dorsal irregularities. We used an experimental rabbit rhinoplasty model that has a human nose-like osteocartilaginous junction. Thus, our goal is to get a more realistic idea about the features of these three materials.

Methods: Thirty New Zealand rabbits weighing 2,100-2,550 g were used. The noses of the rabbits were evaluated with computerized tomographic measurements, "pinch" tests were performed for skin properties, and all were photographed before the surgical procedures. They were divided into three groups: Autogenous cartilage grafts were applied after the rhinoplasty operation in group 1, acellular dermal matrixes were used after the rhinoplasty in group 2, and pericardium allografts were used after the rhinoplasty in group 3. The rabbits were followed up for 4 months before they were evaluated by photography, computerized tomography, and "pinch" tests for the skin properties of the nose. Then they were killed for histopathologic evaluation. Adhesion and resorption rates of the onlay grafts were observed and subdermal thickness measurements were made to determine the fate of the grafts as well as their effects on the overlying skin.

Results: The major advantages of the allografts used in groups 2 and 3 are the ease of obtaining them without any donor site morbidity, shorter operative procedures, and lower distortion rates due to lack of cartilage memory. The results of this study conform to those of previous reports and demonstrate that the used allografts had no adverse effects such as ulceration or extrusion. The evaluation of the internal nasal valve angles before and after the surgical interventions showed that cartilage grafts created a spreader effect as expected, but acellular dermis and solvent-dehydrated pericardium did not. Despite a moderate graft reaction, pericardium or acellular dermis remained intact. None of the materials caused adhesion to the overlying skin.

Conclusion: The results of this experimental study showed that acellular dermis (AlloDerm®) or solvent-dehydrated pericardium (Tutogen) may be used successfully as an "onlay" graft for dorsal nasal problems compared to autogenous cartilage, which is commonly used for this purpose. There has been more cartilage resorption than thought. This should be considered when overcorrection is performed.

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