Biological properties of a biomimetic membrane for guided tissue regeneration: a study in rat calvarial defects

The biological properties of nano-hydroxyapatite/polyamide (nHA/PA66) membrane as a guided tissue regeneration barrier were investigated based on a critical-size calvarial defect model.

Thirty-six Sprague-Dawley rats were divided into four groups: nHA/PA66 membranes, control treated with expanded polytetrafluoroethylene (e-PTFE) membranes, control treated with PA membranes and blank. Bone regeneration in each group was evaluated using morphological, serological, radiographic and histological techniques at 1, 4 and 8 weeks, respectively, post-operation.

Slight degradation of nHA/PA66 membranes was observed by a scanning electron microscope (SEM) at 4 and 8 weeks. The serum alkaline phosphatase level and the integral optical density of neo-bone were significantly higher in the nHA/PA66 group than those in the PA group and blank (P<0.05). Radiographic and histological analysis showed a fully closed cranial defect for both the nHA/PA66 group and the e-PTFE group at 8 weeks. No remarkable difference was found between the nHA/PA66 group and the e-PTFE group at each time interval.

nHA/PA66 membrane promoted bone regeneration as effectively as conventional e-PTFE membrane. Based on a rat study, nHA/PA66 membrane provides a promising alternative to e-PTFE membrane due to the absence of requirement for a second surgery.