title: [Effect of sandblasting particle sizes on bonding strength between porcelain and titanium fabricated by rapid laser forming].
abstract: 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 microm, 120 microm, 250 microm) at a pressure of 0.5 MPa. The cast titanium specimens were used as control, and were sandblasted with 50 microm Al2O3 at the same pressure.
  
  
  RESULTS
  The thermal expansion coefficient of cast titanium [(9.84 +/- 0.42) x 10(-6)/ degrees C] and LRF Ti [(9.79 +/- 0.31) x 10(-6)/ degrees C) matched that of Noritake Ti-22 dentin porcelain [(8.93 +/- 0.36) x 10(-6)/ degrees C). 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 microm [(25.91 +/- 1.02) MPa] and cast titanium [(26.42 +/- 1.65) MPa]. Significantly lower bonding strength was found in LRF Ti-120 microm [(21.86 +/- 1.64) MPa] and LRF Ti-250 microm [(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 microm Al2O3 sandblasting in 0.5MPa air pressure.
authors.affiliation: Department of Prosthodontics, The Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Li-jun
authors.initials: LJ
authors.lastname: Zhang
authors.forename: Zhong-yi
authors.initials: ZY
authors.lastname: Wang
authors.forename: Bo
authors.initials: B
authors.lastname: Gao
authors.forename: Yang
authors.initials: Y
authors.lastname: Gao
authors.forename: Chun-bao
authors.initials: CB
authors.lastname: Zhang
mesh_terms: D001840:Dental Bonding; D003776:Dental Porcelain / Q000528:radiation effects; D019232:Dental Restoration Failure; D006801:Humans; D007834:Lasers; D008422:Materials Testing; D010316:Particle Size; D013499:Surface Properties; D014025:Titanium / Q000528:radiation effects
chemical_list: D003776:Dental Porcelain; D014025:Titanium