Comparison and characterization of multiple biomaterial conduits for peripheral nerve repair

Four biomaterial tubes, poly(lactic-co-glycolic acid) (PLGA), poly(caprolactone fumarate) (PCLF), a neutral oligo[(polyethylene glycol) fumarate] (OPF) hydrogel or a positively charged oligo[(polyethylene glycol) fumarate] (OPF(+)) hydrogel with a PCLF sleeve, have previously been shown to have benefits for nerve repair. However, no direct comparison to identify the optimal material have been made. Herein, these nerve tubes were implanted in a rat sciatic nerve model and nerve regeneration was quantified and compared by using accepted nerve assessment techniques. Using standard statistical methods, no significant differences of individual parameters were apparent between groups despite PCLF showing a tendency to perform better than the others. Using a mean-variance based ranking system of multiple independent parameters, statistical differences became apparent. It was clear that the PLCF tube supported significantly improved nerve regeneration and recovery compared to the other three biomaterial conduits. The ability to simultaneously compare a number of regenerative parameters and elucidate the best material from the combination of these individual parameters is of importance to the nerve regeneration area and has implications for the tissue engineering field. By using this method of comparison, a number of biomaterial constructs may be compared under similar conditions and the optimal construct elucidated using the minimal number of animals and materials.