喷砂粒度对激光快速成形纯钛与瓷结合强度的影响

Effect of sandblasting particle sizes on bonding strength between porcelain and titanium fabricated by rapid laser forming

目的探讨不同喷砂粒度对激光快速成形（laser rapid forming，LRF）纯钛与瓷结合强度的影响，以期为LRF纯钛的临床应用提供参考。方法利用LRF技术加工纯钛，测量LRF纯钛、铸钛和牙本质瓷试件的热膨胀系数（n=3）。分别以0．5MPa压力，50、120、250μm的Al2O3对LRF纯钛表面进行喷砂处理（LRF纯钛-50μm组、LRF纯钛-120μm组、LRF纯钛-250μm组），以0．5MPa压力、50μmAl2O3喷砂处理铸钛试件作为对照（铸钛-50μm组），测量4组钛试件的表面粗糙度（n=10）、表面接触角（n=10）并观察试件表面形貌，4组钛试件烤瓷后（n=5）测量钛-瓷结合强度。结果LRF纯钛与铸钛的热膨胀系数[分别为（9．79±0．31）×10^-6和（9．84±0．42）×10^-6／℃]与牙本质瓷[（8．93±0．36）×10^-6／℃]匹配。随着喷砂粒度的增大，LRF纯钛表面粗糙度增加，表面接触角增大。铸钛-50μm组的钛-瓷结合强度[（26．42±1．65）MPa]略大于LRF纯钛-50μm组[（25．91±1．02）MPa]，两组差异无统计学意义（P〉0．05）；LRF纯钛-120μm组钛-瓷结合强度[（21．86±1．64）MPa]与LRF纯钛-250μm组[（19．96±1．03）MPa]的差异无统计学意义（P〉0．05）；其余各组间钛-瓷结合强度的差异均有统计学意义（P〈0．05）。结论经0．5MPa、50μmAl2O3喷砂处理后．LRF纯钛与瓷的结合强度可达到ISO9693所要求的基本值（25MPa）。

Objective To evaluate the effect of sandblasting particle sizes of Al2O3 on the bonding strength between porcelain and titanium fabricated by laser rapid forming （LRF）. Methods The thermal expansion coefficient, roughness （Ra）, contact angle, surface morphology of titanium surface and the bonding strength between titanium and porcelain were evaluated after the titanium surface being sandblasted using different sizes of Al2O3（50 μm, 120 μm, 250 μm） at a pressure of 0.5 MPa. The cast titanium specimens were used as control, and were sandblasted with 50 μm Al2O3 at the same pressure. Results The thermal expansion coefficient of cast titanium [ （ 9.84±0. 42 ） × 10^ -6/℃ ] and LRF Ti [ （ 9. 79 ± 0. 31 ） × 10 ^-6/℃） matched that of Noritake Ti-22 dentin porcelain [ （ 8. 93 ± 0. 36） × 10^ -6/℃）. When larger size of Al2O3 was used, the value of Ra and contact angle increased as well. There was no significant difference in bonding strength between the LRF Ti-50 μm[（25.91 ±1.02） MPa] and cast titanium [ （26.42±1.65） MPa]. Significantly lower bonding strength was found in LRF Ti-120μm[（21.86 ± 1.64） MPa] and LRF Ti-250 μm[ （ 19.96 ± 1.03） MPa]. Conclusions The bond strength between LRF Ti and Noritake Ti-22 dentin porcelain was above the lower limit value in the ISO 9693 （25 MPa） after using 50 μm Al2O3 sandblasting in 0. 5MPa air pressure.