title: [Changes of surface roughness and glossiness of the composite resins during polishing].
abstract: OBJECTIVE
  To investigate the changes of surface roughness and glossiness of the composite resins during polishing.
  
  
  METHODS
  Nine conventional composite resins were evaluated. Composite specimens were polymerized on celluloid strip, so, smooth surfaces were obtained for each specimen, then the smooth surface of the specimens were sequentially polished with diamond polishing papers grits #240, #320, #400, #600, #800 and #1200. The roughness and glossiness of the central surface at 60 degrees reflex angle were measured.
  
  
  RESULTS
  The results showed that the values of roughness decreased steadily when specimens were polished with sequential polishing paper from coarse to fine one. A further polishing with grit #800, the values of roughness resumed to the pre-polishing values in all the composite specimen. The change of values of glossiness is very small within polishing with #240-#600. A further polishing with grit #800 and #1200, the values of glossiness increased jumpily. The values of glossiness of five composite resins reached or surpassed the level of pre-polishing.
  
  
  CONCLUSIONS
  This study indicates that fine surface would not be gained until the composite resins were polished with grit #800 and #1200 polishing paper.
authors.affiliation: School of Stomatology, Beijing Medical University, Beijing 100081.
authors.forename: A
authors.initials: A
authors.lastname: Ji
authors.forename: C
authors.initials: C
authors.lastname: Gao
authors.forename: K
authors.initials: K
authors.lastname: Ikuemon
mesh_terms: D003188:Composite Resins / Q000737:chemistry*; D003775:Dental Polishing / Q000295:instrumentation / Q000379:methods*; D013499:Surface Properties
chemical_list: D003188:Composite Resins