Injectable tissue-engineered cartilage using commercially available fibrin glue.

OBJECTIVES/HYPOTHESIS: To achieve injectable tissue-engineered cartilage using a commercially available fibrin sealant, and to determine the most suitable fibrin glue concentration, cartilage source, and cultured chondrocyte concentration. STUDY DESIGN: Animal research. METHODS: A total of 28 immunocompetent New Zealand white rabbits were divided into four groups. The cultured chondrocytes from different anatomical sources carried in fibrin glue with and without aprotinin in different concentrations of fibrinogen and thrombin (Tisseell), were injected into forehead and interocular regions of the rabbits. The new tissue formation was harvested at 8 weeks and analyzed through gross and histological analysis. RESULTS: The new tissue formations were found in round, elliptical, and flat forms. The mean value of Tisseell and cell suspension was 0.8 cc in all of the rabbits' injection regions, but the mean volume of the samples in which immature cartilage matrix and mature cartilage was 0.1 cc. In the 20 of the 55 injection regions of rabbits (36, 36%), mature and/or immature cartilage formation were observed. We observed inflammatory reactions, abscess formation, and foreign body reactions around the new cartilage tissue of tissue-engineered cartilage. The comparison of results using different cartilage sources, chondrocyte concentrations, or different fibrin glue concentrations did not show any significant difference. CONCLUSIONS: We observed that changing the concentrations of ingredients of commercially available fibrin glue, the source of the cartilage, or the cultured chondrocyte concentration did not have significant effect on neocartilage formation.

Temporal branch of the facial nerve and its relationship to fascial layers.

OBJECTIVES: To eliminate the inconsistency in the nomenclature, to anatomically and definitively describe the topographic relationship of the temporal branch of the facial nerve to the fascial layers and the fat pads, and to create an effective algorithm to define the safest approaches and planes for surgical procedures in this area. METHODS: The study was performed using 18 hemifacial cadaveric specimens. In 12 hemifacial specimens, the facial halves were coronally sectioned and dissected. In 6 hemifacial specimens, planar dissection was performed layer by layer. RESULTS: The temporal branch of the facial nerve that traversed inside the deep layers of the temporoparietal fascia and the superficial musculoaponeurotic system coursed along the zygomatic arch as 1 (14.3%), 2 (57.1%), 3 (14.3%), and 4 (14.3%) twigs in the specimens. The temporoparietal fascia had no attachment to the zygomatic arch and continued caudally as the superficial musculoaponeurotic system. Adhesions were between the temporoparietal fascia and the superficial layer of the deep temporal fascia around the zygomatic arch. In most specimens, the superficial layer of the deep temporal fascia continued as the parotideomasseterica fascia, and a deep layer abutted the posterosuperior edge of the zygomatic arch. CONCLUSION: An easy and safe surgical approach in this area is to elevate the superficial layer deep to the intermediate fat pad directly on the deep layer of the deep temporal fascia descending to the periosteum along the zygomatic arch.