Surface treatment and modification of dental prostheses using glow discharge treatment

利用自行研制的实验装置，研究了辉光放电处理(GDT)对复合树脂与钛结合的影响。研制的GDT装置具有高压(最大6.5kv)、高频(20 KHz)的电源。在0.2Torr的气氛中抽真空后，在0.4Torr的氩气环境中分几次进行GDT。钛(CpTi)板材经高温恒温处理后，温度升高至20ﾟC，处理时间越长，钛表面越氧化。未处理的蒸馏水与cpTi的接触角为510，但与GDT接触4~5 mm时，接触角显著降低。细菌发光试验表明，GDT显著降低了细菌的菌落数。扫描电子显微镜观察表明，GDT3种复合树脂均能有效去除表面有机物，但不能达到完全杀菌的目的，4种产品中3种复合树脂的粘接强度随GDT值的增加而提高，但不同产品间差异无统计学意义。这是因为牙科粘接剂单体的粘接机理受粘接表面的吸附和键合结构的影响，而不是润湿性本身。用FT-IR-RAS光谱测定了吸附在cpTi表面的单体。经GDT处理后的单体吸收光谱峰高与未处理的无明显差异。这些结果提示，GDT疗法的掌握、治疗条件等尚需进一步研究，才能将其应用于临床。

We -examined the effect of glow discharge treatment (GDT) on the bonding of composite resin to titanium using the experimentally developed device. The developed device for GDT has a power source with high voltage (6.5kv max) and high frequency (20kHz). After the chamber was vacuumed at O.2Torr, GDT was performed with several treatment time at argon gas environment of O.4Torr. Temperature of titanium (cpTi) plate rose by GDT until 20ﾟC.The surface of titanium was oxidized with longer time treatment. Contact angle of distilled water on cpTi with non treatment was 510, but that with GDT for 4-5 mm decreased significantly. Therefore, wettability was enhanced by GDT.Bacterium glowing test indicated GDT decreased the number of bacteria colony significantly. SEM image of the surface of cpTi demonstrated organic matter on the surface was removed by GDT.However, complete sterilization was not performed by GDT.Bonding strengths of cpTi to 3 composite resins among tested 4 products increased with GDT.However, significant difference was not appeared among the products. This was because the bonding mechanism of dental adhesive monomer was influenced by the adsorbed and bonding structures on the bonding surface rather than wettability itself. Adsorbed monomer was measured on the surface of cpTi by FT-IR-RAS spectrum. The peak height of the spectrum from adsorbed monomer was not different between that with GDT and that with non-treatment. These findings suggested that we need more investigation such as holding and treatment conditions of GDT treatment to apply this treatment to clinical situation.