Comparison of Dimensional Accuracy of Acrylic Resin Denture Base using Conventional and RS Tension Methods of Packing- An In-vitro Study

Abstract

Introduction: Retention and stability are some of the important aspects of a successful denture. Laboratory procedures such as methods of packing have a great influence on the outcome of the denture. Different methods such as methods of closing, impression quality, type of acrylic resin, the processing cycle, cooling procedure, and water sorption have been suggested by the researchers to reduce the discrepancy in the dimensional accuracy of the complete removal dentures. Here, an attempt is made to compare conventional and Rafael Saide (RS) Tension techniques in the present study. Aim: The aim of present study was to evaluate and compare the dimensional accuracy of the heat cured denture base processed by the Conventional and RS (Rafael Saide) tension method of packing. Materials and Methods: The present in-vitro study was conducted at the Department of Prosthodontics, Crown and Bridge and Implantology, Modern Dental College and Research Centre, and at Shri Govindram Seksaria Institute of Technology (SGSITS) Indore Madhya Pradesh, India, from September 2014 to October 2015. A metal die with the base and counter was used to fabricate 60 specimens of heat-cured acrylic resin by conventional and RS tension method of clamping. After finishing these denture bases the samples were decoded. All the samples were assessed for the discrepancy in dimensional accuracy when compared with the metal die at five different specified locations. The student’s t-test was used to compare the measurements of the two methods. Results: The average mean marginal gap between all the points by the conventional method was 275.42 µm (minimum 264.5 µm, maximum 282.7 µm), p-value>0.001 and RS tension method was 171.8 µm (minimum 88.66 µm, maximum 248.82 µm), p-value<0.001. There was significant difference in dimensional accuracy when the mean marginal gaps of the two techniques were compared (p-value <0.001). Conclusion: The RS tension clamping method for the fabrication of dimensionally more accurate and more retentive removable complete dentures should be recommended in the laboratories.

Keywords

• conventional clamping technique
• dimensional stability
• maxillary complete denture
• polymethyl methacrylate
• rafael saide tension