Purpose: The purpose of this study was to evaluate the dimensional accuracy of implant
impressions obtained using different tray types and techniques. Materials and Methods: A
partially dentate maxillary Kennedy Class II model was created as a reference model through
three-dimensional (3D) printing. Then, 4.3-mm diameter implant analogs were placed at the
first premolar, first molar, and second molar regions. Five types of trays–metal and plastic
stock trays and custom trays fabricated using liquid crystal display (LCD), fused deposition
modeling (FDM), and urethane dimethacrylate (UDMA) resin–were used to create
impressions. Open- and closed-tray techniques were also compared. In total, 150 impressions
were obtained. The reference model and impressions were scanned using a laboratory scanner.
The positional and angular deviations of implants with different tray types and techniques
were evaluated using the superimposition method. Results: There was no statistically
significant difference (P>0.05) between the impression accuracy with the different tray types
and impression techniques. The angular deviations with plastic and UDMA trays were greater
than those with metal, FDM, and LCD trays. Angular deviation at the second molar by using
closed trays was greater than that using open plastic trays. The highest and lowest positional
deviation were observed at the first molar implant with an open plastic tray impression (mean:
62.46 ± standard deviation: 28.54 μm) and a closed LCD tray impression (36.59 ± 29.93 μm).
The greatest angular deviation was observed with an open FDM tray impression at the first
premolar implant (0.067 ± 0.024°), and the lowest angular deviation was observed with a
closed metal stock tray impression at the second molar implant (0.039 ± 0.025°). Statistical
differences were detected using Mann–Whitney U tests for pair groups and the Kruskal–
Wallis test for groups with more than three comparisons (P>0.05). Conclusion: Plastic and
metal stock trays or conventional and 3D-printed custom trays can be used to obtain implant
impressions for maxillary partially edentulous arches with similar dimensional accuracy. The
five tray types and two techniques may be safely used to obtain impressions of partially
edentulous maxillary arches with three implants.
Schlagwörter: Keywords: implant, deviation, accuracy, 3D, impression