Hydroxyapatite nanowires modified polylactic acid membrane plays barrier/osteoinduction dual roles and promotes bone regeneration in a rat mandible defect model.

Periodontitis is an inflammatory disease leading to tooth loss, alveolar bone absorption and disorder of masticatory function. Guided tissue regeneration (GTR) is one of the most common strategies for regeneration of lost periodontium. During surgical process, barrier membranes, and osteoinductive/osteoconductive materials should be placed, respectively, which may increase risks of infection, bleeding, and difficulty of operation. Here, we introduced a new kind of hydroxyapatite (HAp) nanowires modified polylactic acid (PLA) membrane to achieve barrier/osteoinduction dual functions. The physicochemical property measurements suggested the two sides of the composite membrane did not change after composition. Then a rat mandibular defect model was established to investigate barrier and osteoinductive effects of this composite membrane. After implantation, effects of functional cells engraftment and osteoinduction were detected by scanning electron microscope (SEM), histomorphometric measurement, immunohistochemical staining, and Micro-CT scanning. SEM images showed HAp side engrafted more cells than PLA side. The result of immunohistochemical staining suggested HAp/PLA promoted the expression of bone-related markers. Moreover, there were more newly formed bones with better quality in HAp/PLA group. Therefore, this composite membrane would be a promising biomaterial in tissue engineering for bone regeneration due to its barrier/osteoinduction dual functions.