Assessment of the morphology and dimensional accuracy of 3D printed PLA and PLA/HAp scaffolds

Main 3D Manufacturing Techniques for Customized Bone Substitutes. A Systematic Review

“…Finally, the use of bioceramics combined with polymers (biocomposites)—since the properties of both types of materials are added together—has been shown to provide greater advantages for bone regeneration, from impression accuracy [ 18 ] to compressive strength [ 19 , 22 ] and new bone formation [ 19 , 20 , 21 , 22 , 31 , 32 , 44 ]. To date, the biocompatibility of these composite materials has been demonstrated in in vitro [ 18 , 19 , 20 , 44 ] and in vivo studies with experimental animals only [ 21 , 22 , 31 , 32 , 40 ]. Biocomposites can result from the polymer-ceramic bonding of calcium phosphate (HA or TCP) or bioactive polymer-glass, facilitating cell adhesion and proliferation [ 20 , 32 ] and, as a result, bone regeneration/reparation [ 15 ].…”

“…In this regard, it has recently been reported that the incorporation of hydroxyapatite (HAP) into a biodegradable polymer (i.e., poly l-lactic acid) (PLLA) matrix exhibit bioactivity and osteoconductivity showing excellent bone defect repair capacity with the formation of abundant new bone tissue and blood vessel tissue [ 53 ]. Moreover, authors such as Gendviliene I [ 18 ] proved that biocomposites achieved higher printing accuracy than pure polymers. However, biocomposites reduce the mechanical resistance of pure polymers to some extent [ 21 ].…”

“…With regard to the scaffold fabrication techniques, as we can see in Table 1 and Table 2 , except for two studies that used solvent casting [ 31 ] and thermally induced phase separation (TICS) [ 32 ] and three others that applied the combined lost-wax technique [ 17 , 25 , 29 ], the rest of studies used additive manufacturing techniques. The techniques with the highest number of publications are firstly DIW, and specifically robocasting [ 19 , 23 , 26 , 27 , 42 , 43 , 44 , 46 , 47 , 48 , 49 ], followed by FFF [ 16 , 18 , 20 , 21 , 28 , 39 , 40 , 41 ] and 3D printing [ 22 , 24 , 30 , 36 , 37 , 38 ].…”

“…With the FFF technique (fused filament fabrication) the macropore size usually ranges between 200 and 350 μm [ 16 , 18 , 20 , 21 , 28 , 40 ]. Nevertheless, a great variability of pore size was observed with DIW (from 75 μm [ 23 ] to 1200 μm [ 42 ]) and 3D printing (from 10 μm [ 36 ] to 1000 μm [ 30 ]).…”

Acrylate–gelatin–carbonated hydroxyapatite (cHAP) composites for dental bone-tissue applications

“…[5][6][7][29][30][31] For this reason, a variety of techniques have been used to create three-dimensional (3D) composite scaffolds with different porosities and surface characteristics, of which gas-foaming, 32,33 porogen leaching, 34 microsphere sintering 35 and phase separation/freezecasting, [36][37][38] electrospinning 39 can be mentioned. 3D printing technology makes it possible to produce scaffolds with a high degree of complexity and precision at a micron level, [40][41][42] and a selective laser sintering (SLS) method has also been used to produce 3D structures with well-defined interconnected pores. 43 Most synthetic polymers are highly hydrophobic and the incorporation of a biological polymer, such as collagen, gelatin or hyaluronic acid is a popular method to alter the physicochemical properties of the matrix and promote biological response.…”