Ibraheem Eman Mostafa Ahmed, Hammad Hoda Gaafar Hassan
Removable Prosthodontics, National Research Centre, Cairo, Egypt.
Dental Biomaterials, Batterjee Medical College, Jeddah, Saudi Arabia.
Open Access Maced J Med Sci. 2019 Mar 14;7(5):862-868. doi: 10.3889/oamjms.2019.193. eCollection 2019 Mar 15.
Various clinical cases of thermopress denture base materials necessitate the use of denture adhesives to achieve proper retention and stability of the removable prosthesis. Therefore; the microhardness of these flexible materials as surface property and its' alterations due to the application of various denture adhesives are still crucial issues to be discussed.
This study aimed to investigate the impact of two commercially available denture adhesives (DAs) on microhardness of a flexible denture base material.
A total of 30 duplicate disc specimens (DS) were fabricated from a thermoplastic injection moulded resin (TR). The obtained 30-disc specimens (DS) were stored in distilled water for seven days, and then their microhardness was measured using Knoop Hardness Test (KHN) under a 10 g load for 10 seconds. The denture adhesives were prepared, and 15 DS were immersed in Corega Super Cream, while the other 15 DS were soaked in Fitty Dent Cream. All DS were stored in distilled water at 37°C. After 30 days of immersion in DAs, microhardness of DS was again measured. T-test for paired observation was used to investigate any alterations in microhardness between the baseline and after 30 days of immersion in the DAs. Statistical analysis was performed with SPSS 20®, Graph Pad Prism® and Microsoft Excel 2016 with a significant level set at P ≤ 0.05.
Student`s t-test had revealed a significant difference between both groups after application of denture adhesive as a P value < 0.05. The obtained results showed that DA material type, flexible denture base material and their surface interaction provoke a statistically significant outcome on the mean microhardness.
DAs were found to affect the microhardness of thermoplastic injection moulded resin (TR); which may jeopardise the durability and serviceability of complete denture and patients' acceptance and comfortability.
热压义齿基托材料的各种临床病例需要使用义齿黏附剂来实现可摘义齿的适当固位和稳定性。因此，这些柔性材料的表面性能——显微硬度，以及由于使用各种义齿黏附剂而导致的其变化，仍然是需要讨论的关键问题。
本研究旨在调查两种市售义齿黏附剂对柔性义齿基托材料显微硬度的影响。
用热塑性注塑树脂制作30个重复的圆盘试件。将获得的30个圆盘试件在蒸馏水中储存7天，然后在10克载荷下使用努氏硬度测试法（KHN）测量其显微硬度，持续10秒。制备义齿黏附剂，将15个圆盘试件浸泡在Corega超级乳膏中，另外15个圆盘试件浸泡在Fitty Dent乳膏中。所有圆盘试件均储存在37℃的蒸馏水中。浸泡在义齿黏附剂中30天后，再次测量圆盘试件的显微硬度。采用配对观察的t检验来研究在浸泡义齿黏附剂30天前后的显微硬度变化。使用SPSS 20®、Graph Pad Prism®和Microsoft Excel 2016进行统计分析，显著性水平设定为P≤0.05。
学生t检验显示，在使用义齿黏附剂后，两组之间存在显著差异，P值<0.05。所得结果表明，义齿黏附剂材料类型、柔性义齿基托材料及其表面相互作用对平均显微硬度产生了统计学上的显著影响。
发现义齿黏附剂会影响热塑性注塑树脂（TR）的显微硬度；这可能会损害全口义齿的耐久性和适用性以及患者的接受度和舒适度。
