title: [Research of changes in the mechanical properties and curability of composite core materials modified with ultrafine diamond].
abstract: OBJECTIVE
  As a new kind of reinforcing filler, ultrafine diamond (UFD) is added into photocurable composite core materials. The properties of the materials are then measured to see if there is any improvement.
  
  
  METHODS
  Different content of barium glass and UFD were added into resin matrix to fabricate six groups of photocurable composite core materials. For each group of the materials, the flexural strength, Vicker's micro-hardness and depth of cure were measured. Data of the flexural strength and Vicker's micro-hardness was then collected and analyzed by One-Way ANOVA.
  
  
  RESULTS
  For the two kinds of composites with barium glass of 60% and 70%, only a small quantity of modified UFD with 0.2% weight percentage could improve the flexural strength of the composites by 34% and 21% respectively, the microhardness was improved by 23% and 30% respectively. The depth of cure of the composite core materials were more than 2 mm, which had reached the demand of the corresponding ISO criteria. The addition of UFD could make the composite core materials darker and grayer.
  
  
  CONCLUSIONS
  Micro-quantity of UFD can improve the mechanical properties of composite resins notably, and it will not affect the curability of the materials, but the defect in the color need to be reformed.
authors.affiliation: Dept of Prosthodontics, Hospital of Stomatology, Peking University, Beijing 100081, China.
authors.forename: Xiao-Yu
authors.initials: XY
authors.lastname: Gu
authors.forename: Xiao-Gang
authors.initials: XG
authors.lastname: Hu
authors.forename: Dong
authors.initials: D
authors.lastname: Peng
authors.forename: Xin-Zhi
authors.initials: XZ
authors.lastname: Wang
mesh_terms: D017609:Barium Compounds; D003188:Composite Resins; D018130:Diamond; D006244:Hardness; D008422:Materials Testing; D008689:Methacrylates; D018583:Pliability; D012822:Silicon Dioxide
chemical_list: D017609:Barium Compounds; D003188:Composite Resins; D008689:Methacrylates; C102738:barium glass filler; D012822:Silicon Dioxide; D018130:Diamond