title: Chairside vs. labside ceramic inlays: effect of temporary restoration and adhesive luting on enamel cracks and marginal integrity.
abstract: OBJECTIVE
  To assess the influence of different temporary restorations and luting techniques of labside and chairside ceramic inlays on enamel defects and marginal integrity.
  
  
  METHODS
  120 extracted human third molars received MOD preparations with one proximal box each limited in either enamel or dentin. 64 Cerec 2 inlays and 56 IPS Empress I inlays were randomly assigned to the following groups (fabrication mode: chairside (CS)=no temporary restoration (TR), labside (LS)=TR with Luxatemp (L) inserted with TempBond NE, or Systemp.inlay (SI) without temporary cement), luting technique: SV=Syntac/Variolink II, RX=RelyX Unicem: A: Cerec inlays were luted with (1) CS/SV. (2) CS/SV/Heliobond separately light-cured. (3) CS/RX. (4) LS/L/SV. (5) LS/L/RX. (6) LS/SI/SV. (7) LS/SI/RX. (8) LS/SI/RX with selective enamel etching. B: Empress. (9) L/SV. (10) L/SV/Heliobond separately light-cured. (11) L/RX. (12) SI/SV. (13) SI/SV, Heliobond separately lightcured. (14) SI/RX. (15) SI/RX after selective enamel etching. Before and after thermomechanical loading (TML: loading time of TR 1000×50N+25 thermocycles (TC) between +5°C and +55°C; clinical simulation: 100,000×50N+2500 TC) luting gaps, enamel cracks, and marginal adaptation to enamel and dentin were determined under an SEM microscope (200×) using replicas.
  
  
  RESULTS
  Loading time of temporary restorations negatively affected enamel integrity and enamel chipping (p<0.05). Luxatemp resulted in less enamel cracks than Systemp.inlay (p<0.05). Syntac/Variolink achieved better marginal enamel quality than RelyX Unicem in all groups (p<0.05). Marginal quality in dentin revealed no differences when no temporary cement was used (p>0.05). Temporary cement negatively affected dentin margins when RelyX Unicem was used (p<0.05).
  
  
  CONCLUSIONS
  Chairside-fabricated Cerec inlays reduce the risk of enamel cracks and marginal enamel chipping due to omitted temporary restorations. Syntac/Variolink revealed a significantly better performance than RelyX Unicem.
authors.affiliation: Department of Operative Dentistry and Endodontics, Medical Center for Dentistry, University Medical Center Giessen and Marburg, Georg-Voigt-Str. 3, D-35039 Marburg, Germany. frankbg@med.uni-marburg.de
authors.forename: Roland
authors.initials: R
authors.lastname: Frankenberger
authors.forename: Norbert
authors.initials: N
authors.lastname: Krämer
authors.forename: Andreas
authors.initials: A
authors.lastname: Appelt
authors.forename: Ulrich
authors.initials: U
authors.lastname: Lohbauer
authors.forename: Michael
authors.initials: M
authors.lastname: Naumann
authors.forename: Matthias J
authors.initials: MJ
authors.lastname: Roggendorf
mesh_terms: D001840:Dental Bonding / Q000379:methods*; D003743:Dental Enamel / Q000293:injuries* / Q000648:ultrastructure; D018772:Dental Marginal Adaptation; D003776:Dental Porcelain; D003794:Dental Restoration, Temporary / Q000009:adverse effects / Q000379:methods*; D003799:Dental Stress Analysis; D006801:Humans; D007284:Inlays / Q000379:methods*; D019279:Resin Cements; D018709:Statistics, Nonparametric
chemical_list: D019279:Resin Cements; D003776:Dental Porcelain