title: Penetration of propylene glycol into dentine.
abstract: OBJECTIVE
  This study aimed to evaluate penetration of propylene glycol into root dentine.
  
  
  METHODS
  Safranin O in propylene glycol and in distilled water were introduced into root canals with and without artificial smear layer. Dye diffusion through dentinal tubules was determined spectrophotometrically. The time required for dye to exit through the apical foramen using propylene glycol and distilled water as vehicles was also determined. The extent and areas of dye penetration on the split surfaces of roots were assessed using Adobe Photoshop and NIH Image Software.
  
  
  RESULTS
  Propylene glycol allowed dye to exit faster through the apical foramen. The area and depth of dye penetration with propylene glycol was significantly greater than with distilled water (P < 0.0001). Smear layer significantly delayed the penetration of dye.
  
  
  CONCLUSIONS
  Propylene glycol delivered dye through the root canal system rapidly and more effectively indicating its potential use in delivering intracanal medicaments.
authors.affiliation: Department of Operative Dentistry and Endodontics and Oral Microbiology, Cariology Research Unit, Niigata University School of Dentistry, Niigata, Japan.
authors.forename: E V
authors.initials: EV
authors.lastname: Cruz
authors.forename: K
authors.initials: K
authors.lastname: Kota
authors.forename: J
authors.initials: J
authors.lastname: Huque
authors.forename: M
authors.initials: M
authors.lastname: Iwaku
authors.forename: E
authors.initials: E
authors.lastname: Hoshino
mesh_terms: D004396:Coloring Agents; D003786:Dental Pulp Cavity / Q000378:metabolism; D003804:Dentin / Q000378:metabolism*; D004058:Diffusion; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016555:Matched-Pair Analysis; D014677:Pharmaceutical Vehicles / Q000493:pharmacokinetics; D010619:Phenazines; D019946:Propylene Glycol / Q000493:pharmacokinetics*; D012388:Root Canal Irrigants / Q000627:therapeutic use; D018915:Root Canal Preparation; D016369:Smear Layer; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D013053:Spectrophotometry; D013223:Statistics as Topic; D013997:Time Factors
chemical_list: D004396:Coloring Agents; D014677:Pharmaceutical Vehicles; D010619:Phenazines; D012388:Root Canal Irrigants; D019946:Propylene Glycol; D012973:Sodium Hypochlorite; C009195:safranine T