Evaluating the Efficacy of Plasma Treated Non-resorbable High-density PTFE Membranes on Bone and Tissue Regeneration

Objectives: The application of barrier membranes such as polytetrafluoroethylene (PTFE) membranes for the regeneration of bone and tissue has been studied extensively.¹ Typically, PTFE membranes require primary closure to potentially minimize tissue ingrowth, bacterial infection, membrane movement, and graft exposure.² PTFE with a hydrophobic surface limits the material’s adherence to other surfaces. ³ The purpose of this study was to address limitations by evaluating the effects of plasma pre-treated non-resorbable high density PTFE membranes on bone regeneration.
Methods: Surface energy parameters were assessed for both the untreated and plasma treated membranes utilizing, Water, Ethylene Glycol, and Diiodomethane, in combination with a contact angle machine. (OCA 25) The PTFE membranes were then subjected to an in vivo model, utilizing rats, weighing ~250g, (n=24). Each rat received a circular (5 mm) unilateral calvarial defect that was covered by either a non-treated or plasma treated membrane. After 2-weeks in vivo, the calvaria were harvest, subjected to micro-computed tomography (µ-CT) and 3D reconstructive analysis to evaluate bone regeneration. Histological slices were prepared for qualitative analysis.
Results: Evaluation of contact angles resulted with significant differences (p=0.002) between the control PTFE membranes and plasma PTFE membranes (~105.33°±13.1 vs. 60.1°±13.2). Furthermore, plasma treated membranes had significantly greater overall surface energy (SE), (~36mN/m vs. 14 mN/m, p<0.001), as well as a significant increase in both dispersive and polar SE components. Three-dimensional reconstruction for bone within defect, did not result with significant differences (p=0.75) between nontreated and plasma treated membranes (8.2%±4.7 and 8.8%±3.8, respectively).
Conclusions: Optical contact angle measurement analysis indicates that plasma pre-treated high density PTFE membranes have a higher surface energy leading to better hydrophilicity and adhesive properties. Shorter in vivo time frames are warranted to determine early effects of surface treatment on early bone healing.