Sfondrini Maria Francesca, Cacciafesta Vittorio, Scribante Andrea, Boehme Andreas, Jost-Brinkmann Paul-Georg
Department of Orthodontics, University of Pavia, Pavia, Italy.
Am J Orthod Dentofacial Orthop. 2006 Apr;129(4):541-6. doi: 10.1016/j.ajodo.2005.12.025.
The purpose of this study was to assess the effect of light-tip distance on the shear bond strength and the failure site of brackets cured with 3 light-curing units (high-intensity halogen, light-emitting diode, and plasma arc).
One hundred thirty-five bovine mandibular permanent incisors were randomly allocated to 9 groups of 15 specimens each. Stainless steel brackets (Victory Series, Unitek/3M, Monrovia, Calif) were bonded with a resin-modified glass-ionomer (Fuji Ortho LC, GC Europe, Leuven, Belgium) to the teeth, and each curing light was tested at 3 distances from the bracket: 0, 3, and 6 mm. After bonding, all samples were stored in distilled water at room temperature for 24 hours and subsequently tested for shear bond strength.
When the 3 light-curing units were compared at a light-tip distance of 0mm, they showed no significantly different shear bond strengths. At a light-tip distance of 3 mm, no significant differences were found between the halogen and plasma arc lights, but both lights showed significantly higher shear bond strengths than the light-emitting diode light. At a light-tip distance of 6 mm, no significant differences were found between the halogen and light-emitting diode lights, but both showed significantly lower bond strengths than the plasma arc light. When the effect of the light-tip distance on each light-curing unit was evaluated, the halogen and light-emitting diode lights showed no significant differences among the 3 distances. However, the plasma arc light produced significantly higher shear bond strengths at a greater light-tip distance. No significant differences were found among the adhesive remnant index scores of the various groups, except with the LED light at a distance of 3 mm.
In hard-to-reach areas, the plasma arc curing light is suggested for optimal curing efficiency.
本研究的目的是评估光尖端距离对使用三种光固化设备（高强度卤素灯、发光二极管和等离子弧灯）固化的托槽剪切粘结强度和失效部位的影响。
135颗牛下颌恒切牙随机分为9组，每组15个样本。使用树脂改性玻璃离子水门汀（Fuji Ortho LC，GC Europe，鲁汶，比利时）将不锈钢托槽（Victory Series，Unitek/3M，蒙罗维亚，加利福尼亚）粘结到牙齿上，并在距托槽3个距离处测试每种固化灯：0、3和6毫米。粘结后，所有样本在室温下的蒸馏水中储存24小时，随后测试剪切粘结强度。
当在光尖端距离为0毫米时比较这三种光固化设备，它们的剪切粘结强度没有显著差异。在光尖端距离为3毫米时，卤素灯和等离子弧灯之间没有发现显著差异，但这两种灯的剪切粘结强度均显著高于发光二极管灯。在光尖端距离为6毫米时，卤素灯和发光二极管灯之间没有发现显著差异，但两者的粘结强度均显著低于等离子弧灯。当评估光尖端距离对每种光固化设备的影响时，卤素灯和发光二极管灯在这3个距离之间没有显著差异。然而，等离子弧灯在更大的光尖端距离下产生了显著更高的剪切粘结强度。除了距离为3毫米的发光二极管灯组外，各实验组的粘结剂残留指数评分之间没有显著差异。
在难以触及的区域，建议使用等离子弧固化灯以实现最佳固化效率。
