Elekdag-Turk Selma, Sarac Y Sinasi, Turk Tamer, Sarac Duygu
Department of Orthodontics, Faculty of Dentistry, University of Ondokuz Mayis, Samsun, Turkey.
Eur J Orthod. 2007 Jun;29(3):299-303. doi: 10.1093/ejo/cjm017. Epub 2007 May 19.
The aim of this study was to evaluate different curing times of a light-emitting diode (LED) unit on shear bond strength (SBS) of ceramic brackets bonded to feldspathic porcelain. Ceramic brackets were bonded with a light-cured adhesive to 96 feldspathic porcelain facets. Air-borne particle abrasion was performed using 25 mum aluminium trioxide (Al(2)O(3)) with an air abrasion device from a distance of approximately 10 mm at a pressure of 2.5 bars for 4 seconds, then the porcelain surfaces were etched with 9.6 per cent hydrofluoric acid for 2 minutes. After surface preparation of the porcelain specimens, silane was applied. In groups 1 and 2, the adhesive was cured with a quartz-tungsten-halogen (QTH) unit for 10 and 20 seconds, respectively. The LED was used in the standard mode for 3, 5, and 10 seconds for groups 3, 4, and 5, respectively. For the other three groups, the LED was used in the fast mode for 3, 5, and 10 seconds, respectively. The SBS of the brackets was measured on a universal testing machine. The adhesive remnant index (ARI) scores, damage to the porcelain, and fracture of the ceramic bracket bases were determined. No significant differences were observed for SBS between the eight groups (P=0.087). There was no significant difference between the groups' ARI scores, porcelain damage, and bracket base fracture (P=0.340, P=0.985, and P=0.340, respectively). There was a greater frequency of ARI scores of 0 for all groups. Fifty per cent of the porcelain facets displayed damage. Nineteen ceramic bracket base fractures were observed. No significant difference was found for the SBS of the groups with QTH and LED units and curing times. It is reliable to use LED with a 3-second curing time since it provided adequate bond strength for ceramic brackets bonded to porcelain surfaces.
本研究的目的是评估发光二极管（LED）装置不同固化时间对粘结在长石质瓷上的陶瓷托槽剪切粘结强度（SBS）的影响。将陶瓷托槽用光固化胶粘剂粘结到96个长石质瓷小平面上。使用空气磨蚀装置，以25μm的三氧化二铝（Al₂O₃）在距离约10mm、压力2.5巴的条件下进行空气颗粒磨蚀4秒，然后用9.6%的氢氟酸蚀刻瓷表面2分钟。在对瓷标本进行表面处理后，施加硅烷。在第1组和第2组中，胶粘剂分别用石英 - 钨 - 卤素（QTH）装置固化10秒和20秒。第3组、第4组和第5组中，LED分别以标准模式使用3秒、5秒和10秒。对于其他三组，LED分别以快速模式使用3秒、5秒和10秒。在万能试验机上测量托槽的SBS。确定胶粘剂残留指数（ARI）评分、瓷损伤情况以及陶瓷托槽底座的断裂情况。八组之间的SBS未观察到显著差异（P = 0.087）。各组的ARI评分、瓷损伤和托槽底座断裂之间无显著差异（分别为P = 0.340、P = 0.985和P = 0.340）。所有组的ARI评分为0的频率更高。50%的瓷小平面出现损伤。观察到19例陶瓷托槽底座断裂。使用QTH和LED装置及不同固化时间的组在SBS方面未发现显著差异。使用固化时间为3秒的LED是可靠的，因为它为粘结在瓷表面的陶瓷托槽提供了足够的粘结强度。
