title: Two-body wear of dental restorative materials.
abstract: OBJECTIVE
  The aim of this in vitro study was to determine the two-body wear resistance of modern direct dental restorative materials.
  
  
  METHODS
  Eight standardized specimens were prepared from 14 dental restorative materials (nano-, micro-, hybrid-, macrofilled composites; compomer, silorane, ormocer); a veneering composite (Sinfony) and enamel were used for reference. Vickers hardness (HV) and inorganic filler weight were determined. Specimens were subjected to mastication simulation using a mastication simulator (50 N, 1.2×10(5) cycles, 1.2 Hz) in a pin-on-block design and simultaneous thermal cycling (600 cycles, 5/55 °C, 2 min/cycle). Steatite balls were used as antagonists. Vertical substance and volume loss were determined using cast replicas and a 3D laser scanning device. Means and standard deviations were calculated, and statistical analysis was performed using one-way ANOVA and the Games-Howell test for post hoc analysis (α=.05).
  
  
  RESULTS
  HV ranged between 19 and 76; inorganic filler weight ranged between 44% and 88%. Significantly lowest vertical substance and volume loss were detected for the microfilled composite Heliomolar; enamel yielded similar vertical substance and volume loss. Intermediate wear was found for the other microfilled and hybrid composites as well as the silorane and the ormocers. Significantly highest wear was found for the macrofilled composite Quixfil and the compomer Compoglass F.
  
  
  CONCLUSIONS
  Within the limitations of an in vitro study, the findings indicate similar wear behaviour for silorane- and ormocer-based dental restorative materials. However, correlations between HV, filler content, and wear resistance were poor.
authors.affiliation: Department of Prosthetic Dentistry, University Medical Center Regensburg, 93042 Regensburg, Germany. Sebastian.Hahnel@klinik.uni-regensburg.de
authors.forename: Sebastian
authors.initials: S
authors.lastname: Hahnel
authors.forename: Sabine
authors.initials: S
authors.lastname: Schultz
authors.forename: Christina
authors.initials: C
authors.lastname: Trempler
authors.forename: Bastian
authors.initials: B
authors.lastname: Ach
authors.forename: Gerhard
authors.initials: G
authors.lastname: Handel
authors.forename: Martin
authors.initials: M
authors.lastname: Rosentritt
mesh_terms: D000180:Acrylic Resins; D001732:Bite Force; D003188:Composite Resins; D019232:Dental Restoration Failure; D019554:Dental Restoration Wear; D006244:Hardness; D006801:Humans; D008027:Light; D008422:Materials Testing / Q000379:methods*; D011140:Polyurethanes; D012044:Regression Analysis
chemical_list: D000180:Acrylic Resins; C029012:Composite Dental Resin; D003188:Composite Resins; D011140:Polyurethanes