Oliveira J P, Cochran M A, Moore B K
Indiana University School of Dentistry, Department of Restorative Dentistry, Indianapolis 46202-5186, USA.
Oper Dent. 1996 May-Jun;21(3):110-5.
This study evaluated the effect of bonded amalgam on the fracture strength of teeth using five adhesive systems: Panavia 21, Amalgambond Plus, Imperva Dual Bond, All-Bond 2 Primer/Bonding Resin, and All-Bond 2 Primer/Liner F. Intact teeth and amalgam lined with Copalite were used as control groups. Large MOD preparations were made in 20 extracted maxillary premolars for each group. The teeth were restored with Tytin. All groups were stored in water at 37 degrees C for 15 days and thermocycled 2500 times, over 8-48 degrees C. The specimens were preloaded five times in compression to 10 kg using a 5 mm-in-diameter, cylindrical steel indenter that contacted the teeth only on the cuspal inclines. Then the teeth were loaded to failure at 5.0 mm/min. The failure mode was recorded (amalgam failure, cusp fracture, or failure at the tooth/amalgam interface). The mean fracture strengths were analyzed using ANOVA and Newman-Keuls multiple comparisons. The Imperva Dual Bond group showed the highest mean forces followed by All-Bond 2 Primer/Bonding Resin. The All-Bond 2 Primer/Liner F and Amalgambond Plus groups demonstrated lower means and were not significantly different from the Copalite group. The Panavia 21 group was in between these two groups and was not statistically different from either group. The mean strength of intact teeth was the highest, but its very large coefficient of variation (60%) prevented effective use of these data for statistical comparison. Analysis of the mode of fracture showed that Panavia 21, All-Bond 2 Primer/Bonding Resin, and Amalgambond Plus failed cohesively in the amalgam in 35%, 25%, and 15% of the specimens respectively. This fracture type is a good indication of effective bonding between tooth and amalgam. The most common type of fracture for all the restored groups was the one that occurred at the tooth/restoration interface. This would suggest that current bonding procedures could be improved.
帕纳维亚21、银汞粘结增强剂、因佩尔瓦双粘结剂、全粘结2底胶/粘结树脂以及全粘结2底胶/衬层F。完整牙齿和用科帕利特垫底的汞合金用作对照组。为每组20颗拔除的上颌前磨牙制备大型近中邻面洞形。用泰廷合金修复牙齿。所有组均在37摄氏度的水中储存15天，并在8至48摄氏度之间进行2500次热循环。使用直径5毫米的圆柱形钢压头对标本进行五次预加载，压缩至10千克，该压头仅在牙尖斜面上与牙齿接触。然后以5.0毫米/分钟的速度加载牙齿直至破坏。记录破坏模式（汞合金破坏、牙尖骨折或牙齿/汞合金界面处的破坏）。使用方差分析和纽曼-基尔斯多重比较分析平均断裂强度。因佩尔瓦双粘结剂组显示出最高的平均力，其次是全粘结2底胶/粘结树脂组。全粘结2底胶/衬层F组和银汞粘结增强剂组的平均值较低，且与科帕利特组无显著差异。帕纳维亚21组介于这两组之间，与两组均无统计学差异。完整牙齿的平均强度最高，但其变异系数非常大（60%），导致这些数据无法有效用于统计比较。对断裂模式的分析表明，帕纳维亚21、全粘结2底胶/粘结树脂和银汞粘结增强剂分别在35%、25%和15%的标本中在汞合金内发生内聚破坏。这种断裂类型是牙齿与汞合金之间有效粘结的良好指标。所有修复组最常见的断裂类型是在牙齿/修复体界面处发生的断裂。这表明当前的粘结程序有待改进。
