Perforated membrane for guided bone and tissue regeneration

Abstract

This disclosure describes a membrane configured to guide bone and tissue regeneration for a bone defect. The membrane may comprise a first layer, a second layer, one or more perforations, a binder, and/or other components. The first layer of the membrane may be configured to contact bone. The first layer may include pores configured to promote ingrowth of bone regenerating cells into the first layer. In some implementations, the first layer may be a continuous sheet of microporous material without large perforations. The second layer may be configured to substantially prevent fibrous connective tissue from growing into the bone defect. The second layer may comprise a relatively dense structure. The second layer may be fixedly coupled to the first layer. In some implementations, the perforations may comprise co-axial through-holes having common dimensions through the first layer and the second layer. The perforations may be configured to enhance ossification.

1 . A membrane configured to guide bone and tissue regeneration for a bone defect, the membrane comprising:
 a first layer configured to contact bone, the first layer comprising expanded polytetrafluoroethylene (ePTFE) that has pores formed therein in a size range of 30 microns to 500 microns, wherein the pores are formed during manufacture of the ePTFE and are configured to promote ingrowth of bone regenerating cells into the first layer;   a second layer comprising high density, cell occlusive polytetrafluoroethylene (PTFE) configured to substantially prevent fibrous connective tissue from growing into the bone defect, the second layer comprising a dense structure, the second layer fixedly coupled to the first layer; and   one or more perforations made through the second layer of the membrane, the perforations comprising co-axial through-holes having common dimensions through the second layer, the perforations configured to enhance ossification, wherein the perforations have a diameter of about 0.5 mm or larger.   
     
     
         2 . The membrane of  claim 1 , wherein the perforations are substantially circular and are configured to increase flexibility of the PTFE in the second layer. 
     
     
         3 . The membrane of  claim 1 , wherein the perforations are substantially circular and have a diameter of about 0.5 mm to about 1.0 mm. 
     
     
         4 . The membrane of  claim 1 , wherein the membrane comprises one or more of collagen, bioresorbable polymer, animal tissue, or human tissue. 
     
     
         5 . The membrane of  claim 1 , wherein one or more of a size, a density, or a spacing of the perforations is determined based on one or more of a material that forms the membrane, a thickness of the membrane, or a size of the membrane. 
     
     
         6 . The membrane of  claim 1 , further comprising one or more secondary perforations configured to receive fasteners configured to hold the membrane in place at the bone defect. 
     
     
         7 . The membrane of  claim 6 , wherein the fasteners include one or more of pins, tacks, sutures, or screws. 
     
     
         8 . The membrane of  claim 1 , wherein at least one perforation extends through the first layer of the membrane the further comprising:
 a reinforcement binder configured to be placed over the bone defect and further configured to couple with surrounding bone, the reinforcement binder comprising:
 multiple elongated members extending from a junction, the elongated members including a first elongated member having a free end that extends away from the junction; and 
 a predrilled hole formed in the first elongated member, the predrilled hole configured to receive a fastener that passes through the first layer of the membrane and the second layer of the membrane and holds the membrane in place at the bone defect. 
   
     
     
         9 . The membrane of  claim 8 , wherein the reinforcement binder is formed between the first layer and the second layer of the membrane. 
     
     
         10 . The membrane of  claim 8 , wherein the reinforcement binder is a titanium reinforcement binder and is configured to be bent into a desired shape by a user. 
     
     
         11 . The membrane of  claim 8 , wherein the predrilled hole in the reinforcement binder has a diameter greater than a corresponding perforation made through the first layer of the membrane and the second layer of the membrane, wherein the predrilled hole and the corresponding perforation are coaxially aligned. 
     
     
         12 . The membrane of  claim 1 , wherein the first layer is unperforated. 
     
     
         13 . A membrane configured to guide bone and tissue regeneration for a bone defect, the membrane comprising:
 a first layer configured to contact bone, the first layer comprising expanded polytetrafluoroethylene (ePTFE) that includes pores having a maximum cross-sectional size that is less than 500 microns, wherein the pores are configured to promote ingrowth of bone regenerating cells into the first layer;   a second layer comprising high density, cell occlusive polytetrafluoroethylene (PTFE) configured to substantially prevent fibrous connective tissue from growing into the bone defect, the second layer comprising a dense structure, the second layer bonded to the first layer;   a reinforcement binder provided between the first layer and the second layer of the membrane; and   one or more perforations created through the second layer of the membrane, the perforations comprising through-holes made through the second layer, the through-holes being configured to enhance ossification.   
     
     
         14 . The membrane of  claim 13 , wherein the first layer is formed as a substantially continuous sheet. 
     
     
         15 . The membrane of  claim 13 , wherein the reinforcement binder comprises at least one predrilled hole configured to receive a fastener that passes through at least one of the first or second layer of the membrane and attaches the membrane at the bone defect. 
     
     
         16 . The membrane of  claim 13 , wherein the first layer includes one or more of a lightweight porous polymer, a lightweight porous bioresorbable polymer or collagen. 
     
     
         17 . The membrane of  claim 13 , wherein the reinforcement binder comprises a flexible titanium binder. 
     
     
         18 . The membrane of  claim 13 , wherein one or more perforations are configured to increase flexibility of the second layer. 
     
     
         19 . The membrane of  claim 13 , wherein the first layer is unperforated. 
     
     
         20 . The membrane of  claim 13 , wherein the through-holes are made by piercing at least the second layer.