A method of modifying a 3D-printed polymer structure is provided. The method can include providing an initial 3D-printed polymer structure having at least one exposed surface; treating the exposed surface of the initial 3D-printed polymer structure with plasma to obtain a treated 3D-printed polymer structure having a treated surface; administering an adhesive to the treated surface of the treated 3D-printed polymer structure; and contacting a complementary 3D-printed polymer structure with the treated surface of the treated 3D-printed polymer structure to obtain a modified 3D-printed polymer structure.