Ahmad Akhoundi Mohammad Sadegh, Aghajani Farzaneh, Chalipa Javad, Sadrhaghighi Amir Hooman
Professor, Dental Research Center Dentistry Research Institute & Department of Orthodontics, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
PhD Student, Dental Research Center & Department of Dental Biomaterials, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
J Dent (Tehran). 2014 Mar;11(2):216-24. Epub 2014 Mar 31.
Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin.
Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting, hydrofluoric acid and silane. Maxillary incisor metal brackets were bonded to half of the disks in each group by conventional orthodontic bonding resin and the other half bonded with a nano-filled composite. The samples then were thermocycled for 2000 cycle between 5-55° C. Shear bond strength was measured and the mode of failure was examined. Randomly selected samples were also evaluated by SEM.
The lowest bond strength value was found infeldespathic ceramic bonded by nano-filled composite (p<0.05). There was not any statistically significant difference between other groups regarding bond strength. The mode of failure in the all groups except group 1 was cohesive and porcelain damages were detected.
Since less damages to feldspathic porcelain was observed when the nano-filled composite was used to bond brackets, the use of nano-filled composite resins can be suggested for bonding brackets to feldspathic porcelain restorations.
要求正畸治疗的成年患者数量增加，导致正畸托槽与陶瓷修复体的粘结比以往更多。本研究的目的是评估和比较用传统正畸粘结树脂和一种新型纳米复合树脂将正畸托槽粘结到两种类型陶瓷基底上的剪切粘结强度。
制作了24个长石质瓷盘和24个二硅酸锂陶瓷盘。所有样本均经过喷砂、氢氟酸和硅烷处理。通过传统正畸粘结树脂将上颌切牙金属托槽粘结到每组一半的瓷盘上，另一半用纳米复合树脂粘结。然后将样本在5 - 55°C之间进行2000次热循环。测量剪切粘结强度并检查失效模式。还通过扫描电子显微镜对随机选择的样本进行评估。
用纳米复合树脂粘结的长石质陶瓷的粘结强度值最低（p<0.05）。其他组之间在粘结强度方面没有统计学上的显著差异。除第1组外，所有组的失效模式均为内聚性，且检测到瓷体损伤。
由于使用纳米复合树脂粘结托槽时观察到长石质瓷的损伤较少，因此可以建议使用纳米复合树脂将托槽粘结到长石质瓷修复体上。
