title: Implant positioning errors in freehand and computer-aided placement methods: a single-blind clinical comparative study.
abstract: OBJECTIVE
  Simultaneous insertion of multiple implants may exhibit suboptimal positions, especially in edentulous jaws considered for a fixed restoration. The aim of this study was to compare the incidence of and confounding factors in implant positioning errors related to the use of freehand and computer-aided treatment methods.
  
  
  METHODS
  A total of 353 implants were placed in 54 patients with at least one edentulous jaw using freehand and computer-aided methods involving 16 mucosa- and 12 bone-supported single- and multiple-type stereolithographic surgical guides. At the stage of prosthesis delivery, a blinded examiner evaluated seven positioning error criteria. Results were analyzed by chi-square test and logistic regression.
  
  
  RESULTS
  Interproximal emergence (OR = 2.82, P < .0001), insufficient interimplant distance (OR = 1.42, P < .0001), and improper parallelism (OR = 1.24, P = .001) errors were significantly higher in implants placed by the freehand method. The highest probability of positioning error (88%) was associated with the use of the freehand method, whereas the lowest (6%) was associated with single-type, mucosa-supported guides with other significant confounding factors.
  
  
  CONCLUSIONS
  Utilizing computer-aided methods may alleviate the occurrence of implant positioning errors that are frequently associated with the freehand method. The use of software planning with enhanced viewing capabilities and single-type, mucosa-supported stereolithographic surgical guides in suitable patients minimizes errors.
authors: Department of Oral Implantology, Faculty of Dentistry, Istanbul University, Çapa, Istanbul, Turkey. varisan@istanbul.edu.tr
authors: Volkan
authors: V
authors: Arisan
authors: Cüneyt Z
authors: CZ
authors: Karabuda
authors: Emre
authors: E
authors: Mumcu
authors: Tayfun
authors: T
authors: Özdemir
mesh_terms: D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D017076:Computer-Aided Design; D015986:Confounding Factors, Epidemiologic; D003758:Dental Implantation, Endosseous / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D015921:Dental Implants; D003761:Dental Impression Technique; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007575:Jaw, Edentulous / Q000534:rehabilitation*; D008297:Male; D019300:Medical Errors / Q000517:prevention & control / Q000706:statistics & numerical data*; D008875:Middle Aged; D016037:Single-Blind Method; D012984:Software; D025321:Surgery, Computer-Assisted / Q000379:methods*
chemical_list: D015921:Dental Implants