Evaluation of accuracy of novel approach for the use of silicone impression materials. A comparative in-vitro study

Introduction: Accurate impression is one of the most critical factors affecting the success of the dental prosthesis. With shortage of many dental materials in Egypt lately, Impression making with intermixing of addition and condensation silicone impression materials was suggested and needed to be tested for validation. Aim: Evaluation of the intermix technique of silicone impression materials in terms of trueness and precision. Materials and methods: Fifteen impressions of two step putty/wash impression technique were made for Acrylic dentulous model with #14 had full crown and divided into in 3 groups; group A, condensation silicone, group B, intermix of light body addition silicone over putty condensation and group C, addition silicone. 3D superimposition of STL files of scanned models were made in order to evaluate trueness and precision. Results: Addition silicone had the best trueness followed by condensation silicone and intermix group. Significant difference was found between addition silicone and intermix group but no significant difference was found between intermix group and condensation silicone as well as between addition and condensation silicones. In matter of precision, condensation silicone had best mean deviation value then addition silicone and intermix group. No significant difference was found between the three groups. Conclusion: Intermix technique proved to be a valid option in impression making within limitations of this study. Further studies should be made with bigger sample size and other testing environment.