Assessing the Accuracy of Dental Impressions Fabricated with Modified Plastic Trays Using Compound Wax and Metal Trays: A Comparative Study

Purpose: This study assessed the accuracy of dental impressions generated from modified plastic trays using impression compound material compared with that of impressions made using stock metal and plastic trays. Methods: In this in vitro study, three types of trays-stock plastic trays, modified plastic trays and stock metal trays (control)-were used, with 30 impressions for each tray type. A Nissan typodont was used as the master cast with standardized prepared teeth. Polyvinyl siloxane impression material with light and regular bodies was used for the impressions. For the modified plastic trays, a disc of compound wax was heated in a water bath until the dough state was reached. Then, the dough was placed in the plastic tray and a preliminary impression was made using the wax. These impressions were scanned using a S600 ARTI SCANNER and statistical analysis employing a multivariate analysis of variance was conducted to evaluate the differences among the tray types. Results: Metal trays demonstrated the highest accuracy in dental impressions; however, they may cause patient discomfort. Modified plastic trays, using compound wax, showed significant improvements in accuracy over standard plastic trays, providing a viable alternative when metal trays are unavailable or unsuitable. Conclusion: The study highlights the potential of modified plastic trays as a comfortable and accurate alternative to metal trays. Further refinement and standardization of the modification process can enhance their performance, making them a durable option for dental impressions.