Table of Contents
Journal of Dental Surgery
Volume 2014, Article ID 273079, 6 pages
http://dx.doi.org/10.1155/2014/273079
Research Article

Variables Affecting the Accuracy of Implant Master Casts: An In Vitro Pilot Study

1Department of Prosthodontics, University of Erlangen-Nuremberg, Glueckstraße 11, 91054 Erlangen, Germany
2Department of Oral and Maxillofacial Surgery, Orthopedic Stomatology and Oral Implantology, University of Medicine and Pharmacy “N. Testemitanu,” 158 V. Lupu Street, Orhei, 3500 Chisinau, Moldova

Received 3 April 2014; Accepted 25 April 2014; Published 14 May 2014

Academic Editor: Constantin Landes

Copyright © 2014 Matthias Karl and Victor Palarie. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Impression and master cast accuracy have been identified as being the major determinants of superstructure fit in implant-supported restorations. The goal of this in vitro investigation was to determine the effects of different transfer components, impression materials, disinfection, storage time, and stone type on master cast accuracy. Following impression making from a reference model with two internal-hex bone-level implants and master cast fabrication (eight experimental groups; n = 5), a bar-type measurement device equipped with a strain gauge was fixed on all master casts while strain development was recorded. Statistical analysis was performed applying ANOVA and paired t-tests with the level of significance set at α = 0.05. The transfer components with plastic sleeves caused maximum misfit strain which was significantly greater as compared to click (P = 0.02) and open tray transfer components (P = 0.00). No significant effect on master cast accuracy was recorded for the parameters impression material, impression disinfection, and storage of impressions or casts. Lower strain development was observed in casts poured in type 3 stone as compared to casts poured in type 4 stone (P = 0.01). For the bone-level implant system considered here, the great levels of accuracy could be achieved using pick-up impressions with either click or open tray impression components.