Theodoro Guilherme Teixeira, Fiorin Lívia, Moris Izabela Cristina Maurício, Rodrigues Renata Cristina Silveira, Ribeiro Ricardo Faria, Faria Adriana Cláudia Lapria
Department of Dental Materials and Prosthodontics, Dental School of Ribeirão Preto, University of São Paulo, Av. do Café, s/n, 14040-904, Ribeirão Preto, São Paulo, SP, Brazil.
Department of Dental Materials and Prosthodontics, Dental School of Ribeirão Preto, University of São Paulo, Av. do Café, s/n, 14040-904, Ribeirão Preto, São Paulo, SP, Brazil.
J Mech Behav Biomed Mater. 2017 Jan;65:609-615. doi: 10.1016/j.jmbbm.2016.09.039. Epub 2016 Sep 28.
Dental ceramics have been widely used because of aesthetic, but wear is still questioned. There are relates that ceramic surface is prone to degradation by acidulated fluoride, that can increase wear rates. The aim of this study was to evaluate the effect of neutral and acidulated fluoride gel, used as preventive agents for professional use, at wear and compression strength of dental ceramics IPS e.max ZirPress (ZIR), IPS Empress Esthetic (EMP) e IPS Inline POM (POM). For this, 30 crowns and 30 disks were obtained by heat-pressing. Crowns and disks were submitted to two-body wear test at machine of mechanical loading, simulating occlusion, lateral movement and disocclusion. It was performed 300,000 cycles at 1Hz frequency under 20N load, to simulate 1 year of mastication. Samples were totally immersed during the test and were divided into three groups according to the gel used for immersion (n=10): control, neutral (sodium fluoride 2%) and acidulated (acidulated phosphate fluoride 1.23%). Samples (crowns and disks) were analyzed for vertical height loss after the test using, respectively, profile projector and stereomicroscope. Roughness of worn surface of crowns and disks was evaluated by laser confocal microscopy. Data of height loss and roughness were evaluated by two-way ANOVA and Bonferroni's test. A crown/disk of each group was analyzed by scanning electronic microscopy. After wear resistance tests, crowns were cemented to their abutments and submitted to compressive load at 30° angulation and 1mm/min speed. Type of failures was compared by qui-square test. Ceramic EMP worn less while ZIR worn more. Control gel worn more at crowns while acidulated gel worn more at disks. Surface roughness of samples tested at acidulated gel was significantly lower. Type of failures found at compression resistance tests was affected by ceramic type, but not by gel used. The results suggest that ceramic and fluoride gel affect wear and roughness of worn surface while type of failure is only affected by ceramic.
牙科陶瓷因其美观性而被广泛使用，但磨损问题仍受到质疑。有相关报道称，陶瓷表面容易被酸化氟化物降解，这会增加磨损率。本研究的目的是评估用作专业预防剂的中性和酸化氟化物凝胶对牙科陶瓷IPS e.max ZirPress（ZIR）、IPS Empress Esthetic（EMP）和IPS Inline POM（POM）的磨损和抗压强度的影响。为此，通过热压获得了30个牙冠和30个圆盘。牙冠和圆盘在机械加载机器上进行两体磨损试验，模拟咬合、侧向运动和脱咬合。在20N载荷下以1Hz频率进行300,000次循环，以模拟1年的咀嚼。测试期间样品完全浸没，并根据用于浸泡的凝胶分为三组（n = 10）：对照组、中性（2%氟化钠）和酸化（1.23%酸化磷酸氟）。试验后分别使用轮廓投影仪和立体显微镜分析样品（牙冠和圆盘）的垂直高度损失。通过激光共聚焦显微镜评估牙冠和圆盘磨损表面的粗糙度。高度损失和粗糙度数据通过双向方差分析和Bonferroni检验进行评估。每组的一个牙冠/圆盘通过扫描电子显微镜进行分析。在耐磨性测试后，将牙冠粘结到基牙上，并以与牙长轴呈30°角、1mm/min的速度施加压缩载荷。通过卡方检验比较失效类型。陶瓷EMP磨损较少，而ZIR磨损较多。对照组凝胶在牙冠上磨损较多，而酸化凝胶在圆盘上磨损较多。在酸化凝胶中测试的样品表面粗糙度明显较低。抗压试验中发现的失效类型受陶瓷类型影响，但不受所用凝胶影响。结果表明，陶瓷和氟化物凝胶会影响磨损和磨损表面的粗糙度，而失效类型仅受陶瓷影响。
