Hydrophilic Nanofiber Membrane as Resorbable Membranes in The Rabbit Calvarial Defects

Objectives: Synthetic polymer resorbable membranes have the disadvantage including lack of osteoconductivity and local inflammatory response caused by their acidic degradation product. To solve these problems, some researchers made a hydrophilic resorbable nanofiber membranes with excellent biocompatibility and osteoconductivity. The purpose of this study is to evaluate hydrophilic PLGA membrane in guided bone regeneration of the calvarial defects.
Methods: A total of 20 New Zealand rabbits (3.0 – 3.5 kg body weight, 6 months old) were used. Four circular defects (diameter : 8mm) were formed in rabbit calvarium. The membranes were applied to the following four groups. (1) No membrane, (2) Bio-gide® (Geistlich Pharma AG, Wolhusen, Switzerland), (3) hydrophilic PLGA (85:15) membrane, (4) hydrophilic PLGA (85:15)membrane + TCP(Tricalcium phosphate) – containing bone graft (Osteon 3®, Dentium, Seoul, Korea). Membranes were applied on bone defects. Animals were sacrificed at 2 weeks and 6 weeks, and the tissue specimens were analyzed histologically and were evaluated radiologically.
Results: Histologic evaluation showed that the hydrophilic absorbable nanofiber membranes composed of PLGA (85:15) showed better new bone formation than positive control group in 2 weeks.

Radiological evaluation showed that the average amount of new bone formation after 6 weeks was about 10.47 mm³ in the negative control group and 2.5 times more new bone formation was observed in the hydrophilic PLGA(85:15) membrane with TCP-containing bone graft group (26.52 mm^3)..
Conclusions: These results demonstrate that hydrophilic PLGA (85:15) membrane could potentially serve as a barrier for preferential tissue ingrowth and achieve a desirable therapeutic results for bone tissue regeneration.