Kaimal Aswathy, Ramdev Poojya, Shruthi C S
Postgraduate Student, Department of Prosthodontics, M R Ambedkar Dental College, Bengaluru, Karnataka, India.
Reader, Department of Prosthodontics, M R Ambedkar Dental College, Bengaluru, Karnataka, India.
J Clin Diagn Res. 2017 Aug;11(8):ZC39-ZC43. doi: 10.7860/JCDR/2017/27426.10372. Epub 2017 Aug 1.
Yttria stabilised tetragonal zirconia opens new vistas for all ceramic restoration by the mechanism of transformation toughening, making it much stronger compared to all other ceramic materials. Currently, it is the most recent core material for all ceramic fixed partial dentures due to its ability to withstand high simulated masticatory loads. Problems which have been reported with zirconia restorations involve the core cement interface leading to loss of retention of the prosthesis. Different reasons which have been reported for the same include the lack of adhesion between zirconia and commonly used cements due to absence of silica phase which makes zirconia not etchable. In addition, the hydrophobic nature of zirconia causes low wettability of zirconia surface by the adhesive cements which are commonly used.
The purpose of this in vitro study was to compare and evaluate the effect of two pre-treatments of zirconia, using plasma of argon and silane, on the shear bond strength values of two composite resin cements to zirconia and to evaluate the failure pattern of the debonded areas using stereomicroscopic analysis.
Sixty zirconia discs (10 mm×2 mm) were randomly divided into three groups (n=20), following surface treatment, with airborne particle abrasion, using 110 µm Al2O3: Group I (control), Group II (plasma of argon cleaning), and Group III (application of silane primer). Each group had two subgroups based on the type of resin cement used for bonding: subgroup A; Rely X Ultimate (3M ESPE) and subgroup B; Panavia F (Kuraray). In subgroup A, Rely X universal silane primer and in subgroup B Clearfil ceramic primer was used. Shear bond strengths were determined after water storage for one day and thermocycling for 5000 cycles. Data (megapascal) were analyzed using ANOVA and Bonferroni test. Specimens were subjected to stereomicroscopic analysis, for evaluation of failure pattern.
Group III produced the highest shear bond strength followed by Group II and Group I. Subgroup A showed higher shear bond strength than Subgroup B. Stereomicroscopic analysis showed cohesive failure in Group III, while in Group I adhesive failure was seen.
Silane primer application caused maximum increase in shear bond strength due to increased wettability. Argon plasma treatment was less effective in comparison to silane treatment. Air abrasion when used alone resulted in lower bond strength values, thereby making it necessary to use a combination of surface treatments. Rely X Ultimate cement was superior to Panavia F in terms of adhesive bonding to zirconia.
钇稳定四方氧化锆通过相变增韧机制为全瓷修复开辟了新视野，使其比所有其他陶瓷材料都坚固得多。目前，由于其能够承受高模拟咀嚼负荷，它是全瓷固定局部义齿最新的核心材料。氧化锆修复体报告的问题涉及核心与粘结剂界面，导致修复体固位丧失。对此报告的不同原因包括氧化锆与常用粘结剂之间缺乏附着力，这是由于缺乏二氧化硅相，使得氧化锆不可蚀刻。此外，氧化锆的疏水性导致常用的粘结剂对氧化锆表面的润湿性低。
本体外研究的目的是比较和评估使用氩气等离子体和硅烷对氧化锆进行两种预处理对两种复合树脂粘结剂与氧化锆的剪切粘结强度值的影响，并使用体视显微镜分析评估脱粘区域的失效模式。
六十个氧化锆圆盘（10毫米×2毫米）在表面处理后，使用110微米的Al2O3进行空气颗粒喷砂处理，随机分为三组（n = 20）：第一组（对照组）、第二组（氩气等离子体清洁）和第三组（硅烷底漆应用）。根据用于粘结的树脂粘结剂类型，每组有两个亚组：亚组A；Rely X Ultimate（3M ESPE）和亚组B；Panavia F（可乐丽）。在亚组A中，使用Rely X通用硅烷底漆，在亚组B中，使用Clearfil陶瓷底漆。在储存一天和进行5000次热循环后测定剪切粘结强度。数据（兆帕）使用方差分析和Bonferroni检验进行分析。对标本进行体视显微镜分析，以评估失效模式。
第三组产生的剪切粘结强度最高，其次是第二组和第一组。亚组A显示出比亚组B更高的剪切粘结强度。体视显微镜分析显示第三组为内聚破坏，而第一组为粘结破坏。
由于润湿性增加，硅烷底漆的应用导致剪切粘结强度最大增加。与硅烷处理相比氩气等离子体处理效果较差。单独使用空气喷砂会导致较低的粘结强度值，因此有必要结合使用表面处理。就与氧化锆的粘结而言，Rely X Ultimate粘结剂优于Panavia F。
