A comparative analysis of the accuracy of different direct impression techniques for multiple implants

Abstract

Background: The aim of this study was to compare the accuracy of different direct implant impression techniques for edentulous arches with multiple implants. Methods: Five experimental groups (n = 5) were assembled. Experimental models were created by a direct splinted technique (EG2 to EG5) and a non-splinted technique (EG1). In EG2 and EG3 synOcta impression copings were splinted with an acrylic resin bar, and in EG4 and EG5 with a light-curing composite resin bar. In EG3 and EG5 the resin bars were sectioned, while the other experimental groups were not. Three-dimensional discrepancies were measured by a computerized coordinate measuring machine. Distortion values among the groups were analysed using one-way repeated measures ANOVA. The post hoc Tukey's test was then performed for multiple comparisons. Results: The highest accuracy was obtained in EG2 (mean deviation: 12.70 lm). The acrylic bars demonstrated less deviation (12.70 lm and 22.71 lm) from the master model than the light-curing composite resin groups and the nonsplinted group (41.09 lm). The post hoc Tukey's test showed no significant difference among the groups when the effect of splint design on accuracy was investigated. Conclusions: For situations where impressions of multiple implants are to be made, splinting impression copings with acrylic resin demonstrate superior results than the non-splinted technique and splinting with light-curing composite.

Accuracy of 3 different impression techniques for internal connection angulated implants

“…[11][12][13][14][15][16][17] Moreover, regarding implant angulation, 3 in vitro investigations showed that the splinted technique was more accurate than the nonsplinted technique for making an impression of angulated implants. 5,7,16 Some authors, however, have found no significant differences in the accuracy of internal connection implant impressions with the splinted and nonsplinted techniques. [18][19][20][21] The conflicting findings in the literature concerning the most accurate impression technique might be explained by the different study designs and implant systems used, the different impression and splinting materials, the inaccurate repositioning of the impression copings, the various angulations of the implants, and the variable dental stone expansion.…”

“…1,2 Several studies have investigated the clinical factors affecting the accuracy of implant impressions, such as direct (open tray) or indirect (closed tray) impression techniques, 3 different impression materials, 4 necessity and method of splinting the impression copings, 5,6 implant angulation, and prosthetic connection features. [7][8][9][10] Different implant angulations may create an undesirable path of placement and subsequently an inaccurate impression, especially when multiple implants are used.…”

Accuracy Comparison of Implant Impression Techniques: A Systematic Review

“…Within the splinted techniques, the sectioned resin bar and rejoined with AR is the most commonly used. Overall, 8 out of 10 studies evaluating this specific technique reported it as the most accurate, mainly because of the positive effects of rejoining the AR bar with a minimal amount of the same material to minimize the effects of polymerization shrinkage …”

Application of Intra-Oral Dental Scanners in the Digital Workflow of Implantology

“…A finite element analysis (FEA) study has also shown that passive fit will distribute masticatory forces more evenly over the implants [8]. The aforementioned factors have resulted in the paradigm that passive fit of the framework is one of the key factors for long-term success in implant dentistry [9], [10] stressing the importance of a reliable and precise impression procedure. Several strategies have been developed to ascertain passive fit [3], [11].…”