Types of membranes | Â | Â | |
---|---|---|---|
Bioresorbable membranes | Advantages | Disadvantages | |
Natural membranes | Collagen (different subtypes, predominantly type-I collagen, derived from different animals, (bovine or porcine) and from different sites (tendon or dermis) [40] | - highly biocompatible (no adverse effect to surrounding tissues during degradation) - it promotes wound healing [41] - it allows good integration with connective tissue (fibrous encapsulation with differentiation of a periosteum-like tissue upon the external bony surface) [42, 43] - osteoblasts and fibroblasts can attach to collagen membranes irrespective of its origin [44] - differently cross-linked collagen membranes can promote cell attachment and proliferation [45] | - degradation in vivo is too rapid to maintain the structural integrity necessary for bone regeneration [44] - different cross-linking techniques used to prolong degradation time (it varies from four weeks up to six months) [40, 41, 46] - differently cross-linked collagen membranes can also inhibit cell attachment and proliferation [45] - chemicals used for cross-linking have cytotoxic effects on the surrounding tissues leading to gap formation between the membrane and the connective tissue and facilitate microbial accumulation [43] (to address this, a non-chemical cross-linking nanofibrous collagen membrane has been developed) [47] - variable mechanical properties among the different available membranes - risk of peri-operative rupture - moistening of the membrane (unavoidable in vivo) alters considerably the mechanical properties [48] - possible disease transmission from animals to humans [21, 31] |
 | Chitosan or chitosan-collagen hybrid | - non-toxic natural polymer (polysaccharide) - it enhances wound healing and bone formation [49] - it has hemostatic properties [50] - excellent biocompatibility [51], osteogenic cells can proliferate and express osteogenic markers [51] - chitosan-hybrid membranes have superior mechanical properties [52, 53] | - limited evidence from in vivo studies |
Synthetic membranes | Aliphatic polyesters: PLLA, PLGA, polydioxanone and their co-polymers [52–54] | - the most commonly used and studied bioabsorbable polymer - commercially available and approved for clinical use - by changing the composition and the manufacturing procedure, resorption time, handling properties and mechanical durability can be adjusted to suit the clinical situation [54] - different chemical compositions did not affect on bone regeneration in vivo [55] - slow-degrading membranes induce greater amounts of neovascularization and a thinner fibrous capsule versus fast degrading membranes [56] | - they can induce host-tissue response and foreign body reactions during degradation (by non-enzymatic hydrolysis) [13, 38, 42, 57–59] - the moderate cytotoxic reactions may reduce cellular adhesion [43] |
Non-resorbable membranes | Â | Â | |
Expanded polytetrafuoroethylene (e-PTFE) And others: titanium reinforced ePTFE, high-density-PTFE, or titanium mesh [23] | - extensively studied [26] - biocompatible - they maintain their structural integrity during implantation and have superior space-maintaining properties and capacity for cell occlusion than degradable membranes - semipermeable ePTFE is more effective than the high-density ePTFE [28] - for large segmental bone defects, cylindrical titanium mesh cage used as a scaffold [29] | - a second surgical procedure is required for removal (additional potential risk to the newly regenerated tissues [30]) - membrane exposure is frequent, increasing the risk of secondary infection [31, 32] - e-PTFE can induce slight to moderate cytotoxic reactions and reduce cellular adhesion | |
Novel membranes | Â | Â | |
Alginate membrane | - close assimilation to bone surface - no inflammatory response [60] - easy handling with an alginate base self-setting barrier membrane versus a ready-made membrane [61] -more efficacious versus collagen membranes for mandibular and tibial defects [62, 63] | - limited evidence from in vivo studies | |
- degradable biopolymer poly (lactide-co-ε-caprolactone)(PLCL), - a nano-hydroxyapatite/polyamide(nHA/PA66) composite - an in situ-formed polyethylene-glycol-hydrogel membrane - amniotic membranes - a bacterially-derived polymer - a hybrid membrane consisting of layers of collagen containing hydroxyapatite (HA) and chitosan [69] - polyethersulfone (PES) electrospun nanofibrous membranes [70] - a biomimetic tubular calcium phosphate (CaP)-coated nanofiber mesh combined with platelet rich plasma-mediated delivery of BMP-7 [71] - Latex [72] - membranes with additional anti-bacterial properties or antimicrobial coating [73–75] | - optimized properties for GBR - improved three-dimensional structure and osteogenic bioactivity - they can be loaded with cells to mimic natural bone - no foreign body inflammatory reaction or rejection and satisfactory bone formation - membranes with additional anti-bacterial properties or antimicrobial coating may reduce membrane-associated infections |  |