In vivo evaluation of a regenerative approach to nasal dorsum augmentation with a polycaprolactone-based implant.

[BACKGROUND] Alternative techniques for nasal dorsum augmentation are of paramount importance in reconstructive and plastic surgery. In contrast to autologous cartilage grafts, tissue-engineered grafts can be created de novo and yield low-none donor site morbidity as compared to autologous grafts like rib or ear cartilage. To address this demand, this study investigated the in vivo regenerative potential of polycaprolactone-based implants as an alternative to autologous cartilage grafting during rhinoplasty.

[METHODS] Implants were placed at the nasal dorsum in two groups of minipigs and kept in situ for 2 and 6 months, respectively. Subsequently, the implants were harvested and examined by histology (hematoxylin-eosin, alcian blue, and safranin O) and immunostaining (collagen I and collagen II). Further analysis was performed to measure diameter and distance of polycaprolactone struts.

[RESULTS] Histological examination revealed a persistent formation of connective tissue with some spots resembling a cartilaginous-like matrix after 6 months. In such areas, cells of chondrocyte appearance could be identified. There was a significant decrease in strut diameter but a non-significant difference in strut distance.

[CONCLUSION] Our results indicated that the investigated polycaprolactone-based implants have shown a regenerative and stable nasal dorsum augmentation after 6 months in vivo. Thus, we believe that customized polycaprolactone-based implants could become an alternative technique for nasal dorsum augmentation without the need for autologous cartilage grafts.