title: Fatigue resistance of 2 different CAD/CAM glass-ceramic materials used for single-tooth implant crowns.
abstract: OBJECTIVE
  To evaluate the fatigue resistance of 2 different CAD/CAM in-office monoceramic materials with single-tooth implant-supported crowns in functional area.
  
  
  METHODS
  A metal experimental model with a dental implant was designed to receive in-office CAD/CAM-generated monoceramic crowns. Laterally positioned axial dynamic loading of 300 N at 2 Hz was applied to implant-supported crowns machined from 2 different glass materials for 100,000 cycle. Failures in terms of fracture, crack formation, and chipping were macroscopically recorded and microscopically evaluated.
  
  
  RESULTS
  Four of 10 aluminasilicate glass-ceramic crowns fractured at early loading cycles, the rest completed loading with a visible crack formation. Crack formation was recorded for 2 of 10 leucite glass-ceramic crowns. Others completed test without visible damage but fractured upon removal.
  
  
  CONCLUSIONS
  Lack in chemical adhesion between titanium abutment and dental cement likely reduces the fatigue resistance of machinable glass-ceramic materials. However, relatively better fractural strength of leucite glass-ceramics could be taken into consideration. Accordingly, progress on developmental changes in filler composition of glass-ceramics may be promising.
  
  
  CONCLUSIONS
  Machinable glass-ceramics do not possess sufficient fatigue resistance for single-tooth implant crowns in functional area.
authors: Faculty of Dentistry, Hacettepe University, Ankara, Turkey.
authors: Yeliz
authors: Y
authors: Çavuşoğlu
authors: Erdal
authors: E
authors: Sahin
authors: Riza
authors: R
authors: Gürbüz
authors: Kivanç
authors: K
authors: Akça
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry*; D017076:Computer-Aided Design; D003442:Crowns; D001840:Dental Bonding; D019250:Dental Implants, Single-Tooth; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis / Q000295:instrumentation; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D003765:Models, Dental; D019279:Resin Cements / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D000538:Aluminum Silicates; D003764:Dental Materials; C075815:IPS-Empress ceramic; D019279:Resin Cements; D003776:Dental Porcelain; C078519:leucite; C074543:Cerec; C103502:Variolink; C023506:Glass ceramics; D014025:Titanium