Pressure analysis during impression‐making procedure with various tray designs using a digital occlusion analyzer: An in vitro study

Abstract Purpose The purpose of this study was to evaluate the pressures generated under various relief conditions during impression‐making using the digital occlusal analyzer. Materials and Methods A customized device and impression trays were designed to measure pressure during impression‐making. The left half of the tray consistently had a 0.5 mm relief without vent holes as the control group, while the right half featured varying relief and vent hole designs, resulting in six different trays. Two impression materials (Materials A and B) were loaded onto each tray, and relative pressure was measured using the digital occlusal analyzer (T‐Scan Novus, Tekscan, Inc.). The pressure‐reduction ratio of each experimental side was calculated. Two‐way analysis of variance (ANOVA) was used to evaluate the effect of relief conditions and impression materials on the pressure‐reduction ratio, followed by post hoc multiple comparisons with Bonferroni adjustment ( α = 0.05). Results The pressure‐reduction ratio was significantly influenced by both impression material and relief amount ( p < 0.001), with a significant interaction between the two factors ( p < 0.001). In Material A, pressure reduction was significantly greater at 3 mm compared to 1 and 2 mm, whereas in Material B, pressure reduction increased progressively with greater relief amount. Regarding vent hole design, both impression material and vent hole configuration significantly affected pressure reduction ( p < 0.001), with no significant interaction ( p = 0.767). Designs with smaller but more widely spread vent holes demonstrated significantly greater pressure reductions, with significant differences observed only between the single‐hole design and the two‐ or five‐hole designs. Conclusions Pressure reduction during impression making was influenced by both the viscosity of the material and the pressure‐relief tray design. Forming vent holes yielded more consistent and effective results than adjusting the tray relief amount, highlighting the importance of a comprehensive approach that integrates both impression material selection and the application of various pressure‐relief tray designs.