Comparison 0f Different Impression Procedures on Tissue Displacement

Background: In bilateral partial edentulous condition modified Mc Lean’s Impression technique is most commonly advised, this over impression procedure may be time consuming clinically and possible errors too can be induced while recording. The purpose of this study was to determine the efficacy ofsingle custom tray using medium body elastomeric impression material overmodified Mc Lean’s impression procedure using Zinc oxide eugenol impression paste. Material and Methods: Six patients were selected with bilateral edentulous span in mandibular arch with at least all the molars missing. Patient was subjected to three different impression procedures and cast were constructed. Standardized acrylic occlusal platform was constructed and at three points of the edentulous span the vertical tissue displacement occurring due to different impression procedure was measured. ANOVA test showed the significance, post-hoc testing TukeyHSD was performed to explore the difference among the groups. Results:The relative difference of edentulous tissue displacebility between irreversible hydrocolloid and custom tray A with medium body elastomeric impression material was -0.38, -0.92, -0.67 at 5mm from last present tooth, midway,retromolar pad respectively. At the same three points the difference of edentulous tissue displacebility between hydrocolloid impression procedure and custom tray B with Zinc oxide eugenol impression paste was -0.17, -0.66, -0.52. Study showed at all three positions of edentulous span the tissue displacebility was better with custom tray A using medium body elastomeric impression material and showed a statistical good agreement. Conclusion: Single custom tray and use of medium body elastomeric impression material obtains better functional impression of distal extension edentulous span. This will help clinicians in reducing the chair side time and eliminates errors induced from two stage functional impression techniques.