title: Design and manufacture of customized dental implants by using reverse engineering and selective laser melting technology.
abstract: BACKGROUND
  Recently a new therapeutic concept of patient-specific implant dentistry has been advanced based on computer-aided design/computer-aided manufacturing technology. However, a comprehensive study of the design and 3-dimensional (3D) printing of the customized implants, their mechanical properties, and their biomechanical behavior is lacking.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the mechanical and biomechanical performance of a novel custom-made dental implant fabricated by the selective laser melting technique with simulation and in vitro experimental studies.
  
  
  METHODS
  Two types of customized implants were designed by using reverse engineering: a root-analog implant and a root-analog threaded implant. The titanium implants were printed layer by layer with the selective laser melting technique. The relative density, surface roughness, tensile properties, bend strength, and dimensional accuracy of the specimens were evaluated. Nonlinear and linear finite element analysis and experimental studies were used to investigate the stress distribution, micromotion, and primary stability of the implants.
  
  
  RESULTS
  Selective laser melting 3D printing technology was able to reproduce the customized implant designs and produce high density and strength and adequate dimensional accuracy. Better stress distribution and lower maximum micromotions were observed for the root-analog threaded implant model than for the root-analog implant model. In the experimental tests, the implant stability quotient and pull-out strength of the 2 types of implants indicated that better primary stability can be obtained with a root-analog threaded implant design.
  
  
  CONCLUSIONS
  Selective laser melting proved to be an efficient means of printing fully dense customized implants with high strength and sufficient dimensional accuracy. Adding the threaded characteristic to the customized root-analog threaded implant design maintained the approximate geometry of the natural root and exhibited better stress distribution and primary stability.
authors.affiliation: Resident, Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China.
authors.forename: Jianyu
authors.initials: J
authors.lastname: Chen
authors.affiliation: Professor, Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China. Electronic address: 13580393430@163.com.
authors.forename: Zhiguang
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Associate Professor, Guangzhou Institute of Advanced Technology, Chinese Academy of Science, Guangzhou, China.
authors.forename: Xianshuai
authors.initials: X
authors.lastname: Chen
authors.affiliation: Engineer, Guangzhou Institute of Advanced Technology, Chinese Academy of Science, Guangzhou, China.
authors.forename: Chunyu
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Engineer, Guangzhou Institute of Advanced Technology, Chinese Academy of Science, Guangzhou, China.
authors.forename: Gong
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Resident, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.
authors.forename: Zhewu
authors.initials: Z
authors.lastname: Xu
mesh_terms: D057005:Bioengineering / Q000379:methods*; D001696:Biomechanical Phenomena; D001732:Bite Force; D003198:Computer Simulation; D017076:Computer-Aided Design; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D055119:Elastic Modulus; D020342:Finite Element Analysis; D006801:Humans; D007834:Lasers; D008437:Maxilla / Q000502:physiology; D055595:Mechanical Phenomena; D008954:Models, Biological; D017711:Nonlinear Dynamics; D018583:Pliability; D066330:Printing, Three-Dimensional; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength; D014025:Titanium / Q000737:chemistry; D014092:Tooth Root
chemical_list: D015921:Dental Implants; D003764:Dental Materials; D014025:Titanium