The degradation profile of novel, bioresorbable PCL–TCP scaffolds: An in vitro and in vivo study

Abstract
Degradation studies of scaffolds are important in bone tissue engineering. Previously, novel poly(ε-caprolactone)–20% tricalcium phosphate (PCL–TCP) based scaffolds were developed and proven useful for bone regeneration. In this study in vitro degradation analyses were carried out with the PCL–TCP scaffolds immersed in standard culture medium for 24 weeks. In vivo degradation was performed with the scaffolds implanted in the abdomen of rats for the same period of time. Results demonstrated greater degradation of PCL–TCP scaffolds in vivo than in vitro. At 24 weeks, the increase of average porosity of the scaffolds in vivo was 29.2% compared to 2.65% in vitro. Gel permeation chromatography (GPC) analysis revealed a decrease of 29% and 20% respectively in the Mn and Mw values after 24 weeks in vitro. However, a significant decrease in Mn and Mw values (79.6% and 88.7% respectively) were recorded in vivo. The mechanical properties however, were relatively similar and closely match those of cancellous bone even at 24 weeks. The results showed that the scaffold can be used for dentoalveolar reconstruction and PCL–TCP scaffolds have shown to possess the potential to degrade within the desired time period of 5–6 months and favorable mechanical properties. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008