Color Stability of Re-Injection Acetal Resin with Different Percentages or Several Times

Abstract

Studies in a variety of scientific disciplines have experimented with various techniques for recycling and reusing the materials they utilize on a regular basis, in this study suggest to re cycling waste of acetal resin.Purpose: The purpose of this study was to assess and compare the color change of re-injection acetal resin with different percentages or several times.Material and Methods: Specimens were prepared with dimensions (20±1 mm in diameter x 0.5 mm in thickness) for color stability test and injection according to the manufacture’s instruction for acetal resin as denture base materials and aesthetic clasp. The first group represent control group with (100% New) and other five groups as experimental groups (group II, group III, and group III) with different percentages between new acetal materials and old acetal materials, while two last groups with several times (group IV and group V) only used old acetal materials. Preparation the ratio between the new material with the old material according to pilot study and the best ratio in this study is 25% new acetal material and 75% old acetal material (group II). The old material is preparation by acetal sprue is collected and cutting by cutter and re-injection with new acetal resin.Results: Statistically non-significant difference in color change in re-injection acetal resin, when comparing the control group with mean (1.046±0.094) and re-injection groups with means respectively (1.040 ±0.076,0.942±0.115,0.993±0.137, 0.978±0.060, and 0.970±0.098).Conclusion: Color change was statistically non-significant differences between all studied groups.