Effects of 5 Nanosilica Concentrations and Humid Environments at 6 Different pH Levels on Fracture Toughness and Moisture Absorption of Dental Polymethyl Methacrylate Resin‎ Reinforced With Silica Nanoparticles: An Explorative Experimental Scanning Electron Microscopy Study

IF 1.7 Q3 DENTISTRY, ORAL SURGERY & MEDICINE

Clinical and Experimental Dental Research Pub Date : 2024-12-03 DOI:10.1002/cre2.70006

Mohammad Ali Golshokouh, Nima Refahati, Pouyan Roodgar Saffari

{"title":"Effects of 5 Nanosilica Concentrations and Humid Environments at 6 Different pH Levels on Fracture Toughness and Moisture Absorption of Dental Polymethyl Methacrylate Resin‎ Reinforced With Silica Nanoparticles: An Explorative Experimental Scanning Electron Microscopy Study","authors":"Mohammad Ali Golshokouh, Nima Refahati, Pouyan Roodgar Saffari","doi":"10.1002/cre2.70006","DOIUrl":null,"url":null,"abstract":"<div>\n \n \n <section>\n \n <h3> Introduction</h3>\n \n <p>No study has assessed the effects of nanosilica within polymethyl methacrylate (PMMA) resin and environmental pH on resin's fracture resistance and moisture absorption.</p>\n </section>\n \n <section>\n \n <h3> Methods</h3>\n \n <p>A total of 90 specimens were divided into 30 subgroups of three, as per the ASTM D5045 standard: five groups of nanosilica percentages (0%/2%/5%/7%/10%), each ‎divided into six subgroups of pH levels (pH = 5/6/7/8/9, + “dry” control). The specimens were prepared by mixing silica nanoparticles with PMMA powder in a vacuum mixer. Then, the specimens were mixed with a diluent liquid (TEGDMA) according to the manufacturer's instructions. For each of the five weight percentages, 36 samples were produced. The 18 specimens in each group were randomly divided into six subgroups of pH levels. The specimens were kept in containers of liquid at different pH levels at room temperature for 1 week. Their before- and after-storage weights were recorded to calculate moisture absorption. The fracture resistance test was performed (ASTM D5045 standard) using the three-point bending method. Scanning electron microscopy was performed. Data were analyzed.</p>\n </section>\n \n <section>\n \n <h3> Results</h3>\n \n <p>Both nanosilica extents and pH levels significantly affected the fracture toughness with a significant interaction (<i>p</i> < ‎‎0.00001). All post hoc comparisons of different pH levels (except pH= 5 vs. 6) were significant (<i>p</i> < ‎‎0.0001). All post hoc comparisons of different nanosilica concentrations were significant (<i>p</i> < ‎‎0.0001). Both nanosilica extents and pH levels significantly influenced the fracture toughness with a significant interaction (<i>p</i> < ‎‎0.00001). All post hoc comparisons of different pH levels and also between different nanosilica concentrations were significant (<i>p</i> < ‎‎0.0001). The correlation between moisture absorption and fracture toughness was significant (<i>R</i> = −0.382, <i>p</i> = 0.0009).</p>\n </section>\n \n <section>\n \n <h3> Conclusions</h3>\n \n <p>Fracture toughness decreases when placed in humid and acidic environments. Also, the samples that were placed in a humid environment suffered a brittle fracture. Increasing silica nanoparticles improved fracture toughness (becoming optimal at 5 wt% nanosilica).</p>\n </section>\n \n <section>\n \n <h3> Objective and Materials</h3>\n \n <p>The objective of this study was to investigate the fracture toughness of dental samples made of PMMA reinforced with various percentages of nanosilica at various pH levels. For this purpose, dental resins with various amounts of nanosilica were placed in moist media at different pH values ranging from 5 to 9 (mimicking the normal pH range of the human mouth).</p>\n </section>\n </div>","PeriodicalId":10203,"journal":{"name":"Clinical and Experimental Dental Research","volume":"10 6","pages":""},"PeriodicalIF":1.7000,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cre2.70006","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Clinical and Experimental Dental Research","FirstCategoryId":"1085","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/cre2.70006","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"DENTISTRY, ORAL SURGERY & MEDICINE","Score":null,"Total":0}

引用次数: 0

Abstract

Introduction

No study has assessed the effects of nanosilica within polymethyl methacrylate (PMMA) resin and environmental pH on resin's fracture resistance and moisture absorption.

Methods

A total of 90 specimens were divided into 30 subgroups of three, as per the ASTM D5045 standard: five groups of nanosilica percentages (0%/2%/5%/7%/10%), each ‎divided into six subgroups of pH levels (pH = 5/6/7/8/9, + “dry” control). The specimens were prepared by mixing silica nanoparticles with PMMA powder in a vacuum mixer. Then, the specimens were mixed with a diluent liquid (TEGDMA) according to the manufacturer's instructions. For each of the five weight percentages, 36 samples were produced. The 18 specimens in each group were randomly divided into six subgroups of pH levels. The specimens were kept in containers of liquid at different pH levels at room temperature for 1 week. Their before- and after-storage weights were recorded to calculate moisture absorption. The fracture resistance test was performed (ASTM D5045 standard) using the three-point bending method. Scanning electron microscopy was performed. Data were analyzed.

Results

Both nanosilica extents and pH levels significantly affected the fracture toughness with a significant interaction (p < ‎‎0.00001). All post hoc comparisons of different pH levels (except pH= 5 vs. 6) were significant (p < ‎‎0.0001). All post hoc comparisons of different nanosilica concentrations were significant (p < ‎‎0.0001). Both nanosilica extents and pH levels significantly influenced the fracture toughness with a significant interaction (p < ‎‎0.00001). All post hoc comparisons of different pH levels and also between different nanosilica concentrations were significant (p < ‎‎0.0001). The correlation between moisture absorption and fracture toughness was significant (R = −0.382, p = 0.0009).

Conclusions

Fracture toughness decreases when placed in humid and acidic environments. Also, the samples that were placed in a humid environment suffered a brittle fracture. Increasing silica nanoparticles improved fracture toughness (becoming optimal at 5 wt% nanosilica).

Objective and Materials

The objective of this study was to investigate the fracture toughness of dental samples made of PMMA reinforced with various percentages of nanosilica at various pH levels. For this purpose, dental resins with various amounts of nanosilica were placed in moist media at different pH values ranging from 5 to 9 (mimicking the normal pH range of the human mouth).

Abstract Image

查看原文本刊更多论文

5种纳米二氧化硅浓度和6种不同pH值的潮湿环境对纳米二氧化硅增强牙科聚甲基丙烯酸甲酯树脂断裂韧性和吸湿性的影响：探索性实验扫描电镜研究

目前还没有研究评估聚甲基丙烯酸甲酯（PMMA）树脂中纳米二氧化硅和环境pH对树脂抗断裂性和吸湿性的影响。方法90份样品按ASTM D5045标准分为30个亚组，每组3个：5组纳米二氧化硅含量（0%/2%/5%/7%/10%），每组pH值分为6个亚组（pH = 5/6/7/8/9 +“干”对照）。将二氧化硅纳米颗粒与PMMA粉末在真空混合器中混合制备样品。然后，根据制造商的说明，将标本与稀释液（TEGDMA）混合。对于五个权重百分比中的每一个，产生36个样本。每组18个标本按pH值随机分为6个亚组。将标本置于不同pH值的液体容器中，室温保存1周。记录其储存前和储存后的重量以计算吸湿率。采用三点弯曲法进行抗断裂试验（ASTM D5045标准）。扫描电镜观察。对数据进行分析。结果纳米二氧化硅含量和pH值对断裂韧性均有显著影响，并存在显著的交互作用（p < > > 0.00001）。所有不同pH水平的事后比较（pH= 5 vs. 6除外）均具有显著性（p < 0.0001）。所有事后比较不同纳米二氧化硅浓度都是显著的（p < 0.0001）。纳米二氧化硅含量和pH值都显著影响断裂韧性，并存在显著的相互作用（p < > > 0.00001）。不同pH值和不同纳米二氧化硅浓度之间的事后比较都是显著的（p < 0.0001）。吸湿率与断裂韧性的相关性显著（R = - 0.382, p = 0.0009）。结论在潮湿、酸性环境下，断裂韧性降低。此外，放置在潮湿环境中的样品会发生脆性断裂。增加二氧化硅纳米颗粒可提高断裂韧性（在5 wt%纳米二氧化硅时达到最佳）。目的与材料本研究的目的是研究不同浓度纳米二氧化硅增强PMMA材料在不同pH值下的断裂韧性。为此，将含有不同数量纳米二氧化硅的牙科树脂放置在pH值为5到9的潮湿介质中（模仿人类口腔的正常pH值范围）。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Clinical and Experimental Dental Research DENTISTRY, ORAL SURGERY & MEDICINE-

CiteScore

3.30

自引率

5.60%

发文量

165

审稿时长

26 weeks

期刊介绍： Clinical and Experimental Dental Research aims to provide open access peer-reviewed publications of high scientific quality representing original clinical, diagnostic or experimental work within all disciplines and fields of oral medicine and dentistry. The scope of Clinical and Experimental Dental Research comprises original research material on the anatomy, physiology and pathology of oro-facial, oro-pharyngeal and maxillofacial tissues, and functions and dysfunctions within the stomatognathic system, and the epidemiology, aetiology, prevention, diagnosis, prognosis and therapy of diseases and conditions that have an effect on the homeostasis of the mouth, jaws, and closely associated structures, as well as the healing and regeneration and the clinical aspects of replacement of hard and soft tissues with biomaterials, and the rehabilitation of stomatognathic functions. Studies that bring new knowledge on how to advance health on the individual or public health levels, including interactions between oral and general health and ill-health are welcome.