Fig. 1. Schematic of elastic modulus test positions of tissues around bone hole drilled by laser

Fig. 2. Comparison of elastic modulus distributions of bone tissues around bone holes drilled by lasers with different power densities and by mechanical drill bit

Fig. 3. AFM morphologies and DMT modulus diagrams of bone tissues around bone holes drilled by laser and by mechanical drill bit. (a1)(a2) Intrinsic bone tissue; (b1)(b2) region Ⅰ near bone hole drilled by laser; (c1)(c2) region Ⅱ near bone hole drilled by laser; (d1)(d2) region Ⅰ near bone hole drilled by mechanical drill bit; (e1)(e2) region Ⅱ near bone hole drilled by mechanical drill bit

Fig. 4. Analysis of fractal characteristics of bone tissues based on AFM images. (a) Region Ⅰ near bone hole drilled by laser; (b) region Ⅱ near bone hole drilled by laser; (c) region Ⅰ near bone hole drilled by mechanical drill bit; (d) region Ⅱ near bone hole drilled by mechanical drill bit

Fig. 5. SEM images of inner-wall of bone hole. (a) Bone hole drilled by laser; (b) bone hole drilled by mechanical drill bit

Fig. 6. Finite element simulation of bone hole wall anti-instability under axial force. (a) Finite element model with cortical bone screw inserted in heterogeneous four-phase composite bone tissue; (b) stress distribution in hone hole drilled by laser; (c) stress distribution in bone hole drilled by mechanical drill bit