Pilo R, Brosh T, Chweidan H
Department of Oral Rehabilitation, Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Israel.
J Dent. 1998 Jul-Aug;26(5-6):467-72. doi: 10.1016/s0300-5712(98)00023-2.
The purpose of the present study was to assess the effectivenes of several adhesives in bonding amalgam in order to recover tooth stiffness. A non-destructive experimental methodology was adopted, using strain gauges bonded to the midbuccal surfaces of 40 teeth, with sequential evaluation of loaded intact, prepared and restored stages of the same tooth. Continuous strain measurement as a function of the applied load was acquired by A/D equipment and a data acquisition programme. The strain-force behaviour of the sound teeth under non-axial force up to 97.5 N served as the baseline. The five experimental groups (8 x 5) consisted of control (no adhesive) and four different adhesives. One-way analysis of variance with repeated measures was calculated for the deformation ratio, relative stiffness and recovery values. Reductions in tooth structure by cutting a mesio-occlusal-distal preparation, width one-third intercuspal distance, resulted in 39-52% loss of buccal cusp stiffness. Non-bonded amalgam produced negligible increase (5%) in the stiffness recovery values of the buccal cusps. The adhesives splinted the cusps together, thereby decreasing cuspal flexure and increasing relative stiffness values. Recovery values obtained ranged from 39% to 61%. Assuming that cusp fracture occurs as a result of brittle tooth structure fatigue, amalgam adhesives may contribute to the strengthening of weakened cusps.
本研究的目的是评估几种粘结剂粘结汞合金以恢复牙齿硬度的有效性。采用了一种非破坏性实验方法，将应变片粘贴在40颗牙齿的颊面中部，对同一颗牙齿的加载完整、预备和修复阶段进行连续评估。通过A/D设备和数据采集程序获取作为施加负荷函数的连续应变测量值。将健全牙齿在高达97.5 N的非轴向力作用下的应变-力行为作为基线。五个实验组（8×5）包括对照组（不使用粘结剂）和四种不同的粘结剂。对变形率、相对硬度和恢复值进行了重复测量的单向方差分析。通过制备近中-咬合-远中洞形（宽度为牙尖间距的三分之一）来减少牙齿结构，导致颊尖硬度损失39%-52%。未粘结的汞合金使颊尖硬度恢复值增加可忽略不计（5%）。粘结剂将牙尖固定在一起，从而减少牙尖弯曲并增加相对硬度值。获得的恢复值范围为39%至61%。假设牙尖骨折是由于脆性牙齿结构疲劳所致，汞合金粘结剂可能有助于增强薄弱牙尖。
