Type | Materials (M) Physical properties (P) | Method/Outcomes | Ref |
---|---|---|---|
Groove | M: PLCL-GN P: 20 µm size and 20.96 ± 1.26 MPa tensile strength | Model: In vitro/In vivo, Period: 12 weeks, Damage length: 10 mm, Outcome: Promoted cell migration, adhesion, and elongation, and the directional growth of neurites/axons. Its induce the myelin sheath, faster nerve regeneration and a 20-fold functional recovery | [78] |
M: CS-AS P: 46/18 μm groove/ridge sizes | Model: In vitro, Period: 3 days, Outcome: Increasing axon length by 80% and neurite length by 20%, reducing axon winding and promoting directional growth of neurites/axons, and enhancing cell orientation | [79] | |
M: Silk fibroin P: 10, 30, and 50 µm size | Model: In vitro, Period: 3 days, Outcome: Enhancing cell orientation and directional growth of neurites/axons within a width of 30 µm, regulating cone growth along grooves | [80] | |
M: PCL-PLA P: Sharp and wide ridges with 5 µm depth and groove of 15–20 µm | Model: In vitro/In vivo, Period: 16 weeks, Damage length: 10 mm, Outcome: Enhanced adhesion in wide ridges, increased directional growth of neurites/axons and cell orientation in short ridges, increased axon numbers, and cross-sectional area of axon in wide ridges | [81] | |
M: CS P: Shapes of grating and isosceles triangle with 4 µm ridges, 6 µm groove, ~ 1.6 µm depth | Model: In vitro, Period: 3 days, Outcome: Despite the equal distribution among all platforms, the grating increased the directional growth of neurites/axons and cell orientation. It also reduced actin dispersion and increased cell polarization compared to other groups. However, cells on the scalene triangle platform exhibited the most displacement | [82] | |
M: Gelatin-coated PLCL P: Groove/ridge/depth: 3/3/4 µm or 10/10/4 µm | Model: In vitro, Period: 24 h, Outcome: Grooves 3/3/4 μm had a greater impact than other groups, leading to increased migration, cell orientation, directional growth of neurites/axons, vinculin expression and adhesion by enhancing β1 integrin, Rac1, RhoA, and Cdc42 | [83] | |
M: PLLA-MTMC P: Groove/ridge/depth: 40/20/10 µm or 20/20/10 µm | Model: In vitro, Period: 5 days, Outcome: The 40/20 µm groove enhanced adhesion by cadherin, neurocan, and vinculin, leading to increased directional growth of neurites/axons, improved cell orientation, and well-organized filopodia and lamillopodia | [84] | |
Channel | M: PLATMC P: 4 channels: dimensions from 400 to 1400 nm | Model: In vitro/In vivo, Period: 12 weeks, Damage length: 10 mm, Outcome: Improved directional growth of neurites/axons, axon length, cell orientation, NCV (up to ~ 15%), and DCMAP (up to ~ 40%), coupled with enhanced cell number (~ 61%), myelin thickness (~ 50%) and vessels within the channels (~ 25%) | [85] |
M: Silk fibroin P: 5 channels: dimension ~ 570 µm | Model: In vitro/In vivo, Period: 12 weeks, Damage length: 20 mm, Outcome: By enhancing neurite/axon directional growth and improving cell orientation, the channels facilitated rapid recovery of the damaged tissue by increasing the number of nerve fibers | [86] | |
M: Chitosan/N-succinyl-chitosan P: Conduit with internal fibers and holes of 66 µm | Model: In vitro/In vivo, Period: 12 weeks, Damage length: 10 mm, Outcome: Enhanced cell migration, directional neurites/axons length, myelin membrane, SFI, NCV, and gastrocnemius muscle, as well as improved cell adhesion and nerve cell viability | [87] | |
M: gelatin methacrylate P: 4 channels with internal diameter of 1.2–2 mm | Model: In vitro, Period: 7 days, Outcome: Cell migration increased, especially in larger diameter, enhanced directional growth of neurites/axons, improved cell orientation, increased nerve buds, and enhanced cell junctions with each other | [88] | |
Pillar | M: PMMA P: Cylindrical shape, 6.5 µm pitch, 1 µm height | Model: In vitro, Period: 7 days, Outcome: Improving cell differentiation, increasing the length of axons and directional growth of neurites and axons | [89] |
M: PDMS@PEDOT:PSS P: 2.9–3.1 µm height and distance of 15 or 30 µm | Model: In vitro, Period: 24 h, Outcome: Increased adhesion, increased directional growth of neurites/axons, increased cell differentiation and enhanced cell orientation | [90] | |
M: SU-8 P: 812–853 nm height, 430 nm diameter and distance of 1.2–1.22 µm | Model: In vitro, Period: 3 days, Outcome: Despite cell orientation and improved filopodia, pillars hinder the directional growth of neurites/axons, cell soma, and the differentiation of nerve cells. The combination of pillars with grooves further amplified these effects | [91] | |
M: Silicon P: 5 µm height, 400 nm diameter and 0.8–5 µm distance | Model: In vitro, Period: 24 h, Outcome: Enhancing cell polarization, aligning neurites, and strengthening cell orientation to improve directional growth of neurites/axons and increase filopodia at 2 µm intervals | [92] | |
Pit | M: PCL, PLA, PCL-PLA P: the surface size ranged from 0.5–30 µm2 with 0.8 to 6.2 µm in diameter | Model: In vitro, Period: 6 days, Outcome: Despite the increased proliferation and differentiation of cells in the PCL and PCL + PLA groups, the directional growth of neurites/axons and the length of neurites showed greater increases in the PLA and PCL + PLA groups | [93] |