title: Nanohybrid composite vs. fine hybrid composite in extended class II cavities: clinical and microscopic results after 2 years.
abstract: OBJECTIVE
  To evaluate the clinical behavior of two different resin composites in Class II cavities over a period of 2 years in a controlled prospective split-mouth study.
  
  
  METHODS
  30 subjects received 68 direct resin composite restorations (Grandio bonded with Solobond M: n=36, Tetric Ceram bonded with Syntac: n=32) by one dentist in a private practice. All restorations were replacement restorations, 24 cavities (35%) revealed no enamel at the bottom of the proximal box, in 33 cavities (48%) the proximal enamel width was < 0.5 mm. The restorations were examined according to modified USPHS criteria at baseline, and after 0.5, 1, and 2 years. At each recall, impressions were taken to prepare replicas. Replicas of 44 selected subjects were assessed for marginal quality under a stereo light microscope (SLM) at x130, and 22 replicas were assessed under a SEM at x200.
  
  
  RESULTS
  Both recall rate and survival rate were 100% after 2 years of clinical service. No significant difference was found between the restorative materials (P > 0.05; Mann-Whitney U-test). A significant deterioration was found over time for marginal integrity, tooth integrity, restoration integrity and proximal contact (P < 0.05; Friedman test). SLM and SEM analysis of restoration margins only revealed differences in the amount of detectable perfect margins, in favor of Tetric Ceram (P < 0.05). Both materials performed satisfactorily over the 2-year observation period.
authors.affiliation: Department of Pediatric Dentistry, University Medical Center Carl Gustav Carus, Technical University Dresden, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Krämer
authors.forename: Christian
authors.initials: C
authors.lastname: Reinelt
authors.forename: Franklin
authors.initials: F
authors.lastname: García-Godoy
authors.forename: Michael
authors.initials: M
authors.lastname: Taschner
authors.forename: Anselm
authors.initials: A
authors.lastname: Petschelt
authors.forename: Roland
authors.initials: R
authors.lastname: Frankenberger
mesh_terms: D000328:Adult; D003116:Color; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003737:Dental Cavity Preparation / Q000145:classification*; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry*; D019554:Dental Restoration Wear; D003793:Dental Restoration, Permanent / Q000145:classification*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D053761:Nanocomposites / Q000737:chemistry*; D011446:Prospective Studies; D016628:Replica Techniques; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C509998:Grandio; D019279:Resin Cements; C425825:Solobond M; C078484:Syntac dentine adhesive; C121818:Tetric ceram