Effect of 2 impression techniques on the dimensional accuracy of working implant prosthesis models: an in vitro study

J Craniofac Surg. 2014 May;25(3):822-7. doi: 10.1097/SCS.0000000000000715.

Abstract

Purpose: Implant impressions and working models form integrated precision systems for registration and transmission of clinical data. The components of implant systems have a dimensional tolerance capable of introducing inaccuracies in the impression, thus in the prosthetic framework. This article aimed at comparing 2 repositioning impression techniques: one using impression copings (conventional technique) and the other using the final abutments as impression copings (interceptive technique).

Materials and methods: Two experimental models, one with 4 parallel implants and the other with 4 nonparallel implants, were used to make silicone impressions. Twenty impressions were made with the conventional technique, and a further 20 were made with the interceptive technique. Three-dimensional images acquired with a three-dimensional scanner were measured using a three-dimensional image analysis software, comparing models obtained from the impressions with the experimental models. Data were statistically analyzed by means of confidence intervals calculated with the mean (α = 0.05), descriptive (box plot), and bivariate analyses.

Results: Statistic analysis highlighted significant differences among models obtained using both techniques: the interceptive technique generated working models with less distortion and variability.

Conclusions: For internal-connection implants, the interceptive technique provided significantly more precise working models than did the conventional technique.

Publication types

  • Comparative Study

MeSH terms

  • Dental Abutments
  • Dental Implant-Abutment Design
  • Dental Implants*
  • Dental Impression Materials / chemistry*
  • Dental Impression Technique* / instrumentation
  • Dental Marginal Adaptation
  • Dental Materials / chemistry
  • Dental Prosthesis Design*
  • Humans
  • Image Processing, Computer-Assisted / methods
  • Imaging, Three-Dimensional / methods
  • Materials Testing
  • Models, Dental*
  • Polyvinyls / chemistry
  • Siloxanes / chemistry
  • Surface Properties
  • Titanium / chemistry

Substances

  • Dental Implants
  • Dental Impression Materials
  • Dental Materials
  • Polyvinyls
  • Siloxanes
  • vinyl polysiloxane
  • Titanium