title: Accuracy of surgical guides made from conventional and a combination of digital scanning and rapid prototyping techniques.
abstract: BACKGROUND
  Surgical guides aid in accurately placing dental implants to achieve a predictable restorative outcome. Which surgical guide fabrication technique results in the most accurately fitting surgical guide is unknown.
  
  
  OBJECTIVE
  The purpose of this investigation was to determine the internal fit of dental implant surgical guides on dentate and edentulous ridges by using implant surgical guides fabricated from conventional and computer-aided design/computer-aided manufacturing (CAD/CAM) techniques.
  
  
  METHODS
  Eighty surgical guides were fabricated from conventional and CAD/CAM techniques; half were designed from Kennedy Class 2 (K2) casts, and half were designed from Kennedy Class 3 (K3) casts. Conventional surgical guides were fabricated from acrylic resin. The CAD/CAM surgical guides were scanned by using cone beam computed tomography (CBCT) or an optical scan (OS). The guides were printed with stereolithography (SL) or 3-dimensional digital printing (3DP). All surgical guides were cemented to their respective design casts, sectioned, and measured at standardized locations. A 2-way ANOVA and the post hoc Fisher least square difference t test was performed (α=.05).
  
  
  RESULTS
  The 2-way ANOVA indicated that the difference between surgical guide groups and Kennedy class was statistically significant (P<.05) and the interaction between groups and Kennedy class was statistically significant (P<.05). The OS/3DP CAD/CAM guide was the best-fitting cast for the K2 cast group, and the conventional guide was the best-fitting guide for the K3 group.
  
  
  CONCLUSIONS
  Conventionally fabricated and OS surgical guides have greater accuracy of fit than CBCT scanned surgical guides.
authors: Resident, Graduate Prosthodontics, Department of Prosthodontics, Lackland Air Force Base San Antonio, Texas.
authors: Ashley
authors: A
authors: Reyes
authors: Assistant Professor, Department of Comprehensive Dentistry, The University of Texas Health Science Center at San Antonio, Texas. Electronic address: ilserturkyilmaz@yahoo.com.
authors: Ilser
authors: I
authors: Turkyilmaz
authors: Professor, Department of Pathology, The University of Texas Health Science Center at San Antonio, Texas.
authors: Thomas J
authors: TJ
authors: Prihoda
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D002484:Cementation / Q000379:methods; D017076:Computer-Aided Design; D054893:Cone-Beam Computed Tomography / Q000379:methods; D003758:Dental Implantation, Endosseous / Q000295:instrumentation*; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry; D004867:Equipment Design; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000145:classification / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D003765:Models, Dental; D061848:Optical Imaging / Q000379:methods; D066330:Printing, Three-Dimensional; D013499:Surface Properties; D014584:User-Computer Interface; D015035:Zinc Oxide-Eugenol Cement / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D003764:Dental Materials; D015035:Zinc Oxide-Eugenol Cement