Arora Saryu, Khindaria S K, Garg Sushant, Mittal Sanjay
Department of Prosthodontics, Swami Devi DyalHospital and Dental College 40, Barwala Panchkula, India.
Contemp Clin Dent. 2011 Jul;2(3):182-7. doi: 10.4103/0976-237X.86452.
Heat cured acrylic resins undergo dimensional changes during polymerization. Dimensional changes which occur in the heat cure acrylic resins are shrinkage and expansion which affects the fit of the denture and occlusal relationship.
The purpose of this study was to access the linear dimensional changes of four heat cure acrylic resins before and after curing and compare the changes among four different acrylic brands.
Twenty four patients irrespective of age and sex were taken and four commercially available brands were procured. After the teeth arrangement on the mandibular trial denture, two pins were fixed in central fossae of first molar on both sides and one pin in the cingulum of left central incisor. Meliodent heat cure acrylic resin was used in Group A; Trevalon heat cure acrylic resin was used in Group B; Triplex heat cure acrylic resin was used in Group C and Vertex heat cure acrylic resin was used in Group D. Linear measurements of the trial wax up before and after curing and before and after finishing and polishing were measured and compared. Collected data was analyzed with analysis of variance and 't' test at 95% level of confidence (P=0.05).
The maximum percentage changes were seen in cases of Group A (Meliodent) followed by Group B, Group C and Group D (Trevalon, Triplex and Vertex). Meliodent showed the highest percentage change i.e. 1.18% and Vertex showed least percentage change of 0.37 %.
Shrinkage occurred after curing and after finishing and polishing, which varies significantly with the four commercially available heat cure acrylic resins. Among the four different brands of heat cure acrylic resin Group D (Vertex) had the least linear dimensional changes after curing and after finishing and polishing, so that D (Vertex) could be the material of choice for fabrication of complete denture among the four brands.
热固化丙烯酸树脂在聚合过程中会发生尺寸变化。热固化丙烯酸树脂中发生的尺寸变化包括收缩和膨胀，这会影响义齿的贴合度和咬合关系。
本研究的目的是评估四种热固化丙烯酸树脂固化前后的线性尺寸变化，并比较四种不同丙烯酸树脂品牌之间的变化。
选取24名患者，不分年龄和性别，并采购了四个市售品牌的产品。在下颌试验义齿上排牙后，在两侧第一磨牙的中央窝固定两根销钉，在左中切牙的舌隆突固定一根销钉。A组使用Meliodent热固化丙烯酸树脂；B组使用Trevalon热固化丙烯酸树脂；C组使用Triplex热固化丙烯酸树脂；D组使用Vertex热固化丙烯酸树脂。测量并比较试验蜡型在固化前后以及修整和抛光前后的线性尺寸。收集的数据采用方差分析和95%置信水平的“t”检验进行分析（P = 0.05）。
A组（Meliodent）的变化百分比最高，其次是B组、C组和D组（Trevalon、Triplex和Vertex）。Meliodent的变化百分比最高，为1.18%，Vertex的变化百分比最低，为0.37%。
固化后以及修整和抛光后会发生收缩，这在四种市售热固化丙烯酸树脂之间有显著差异。在四种不同品牌的热固化丙烯酸树脂中，D组（Vertex）在固化后以及修整和抛光后的线性尺寸变化最小，因此在这四个品牌中，D组（Vertex）可能是制作全口义齿的首选材料。
