title: Effect of disinfection on irreversible hydrocolloid and alternative impression materials and the resultant gypsum casts.
abstract: BACKGROUND
  Many new products have been introduced and marketed as alternatives to traditional irreversible hydrocolloid materials. These alternative materials have the same structural formula as addition reaction silicone, also known as vinyl polysiloxane (VPS), impression materials. Currently, there is limited in vitro and in vivo research on these products, including on the effects of chemical disinfectants on the materials.
  
  
  OBJECTIVE
  The purpose of this study was to compare the effects of a spray disinfecting technique on a traditional irreversible hydrocolloid and 3 new alternative impression materials in vitro.
  
  
  METHODS
  The tests were performed in accordance with the American National Standards Institute/American Dental Association (ANSI/ADA) Specification Nos. 18 and 19. Under standardized conditions, 100 impressions were made of a ruled test block with an irreversible hydrocolloid and 3 alternative impression materials. Nondisinfected irreversible hydrocolloid was used as the control. The impressions were examined for surface detail reproduction before and after disinfection with a chloramine-T product. Type III and Type V dental stone casts were evaluated for linear dimensional change and gypsum compatibility. Comparisons of linear dimensional change were analyzed with 2-way ANOVA of mean ranks with the Scheffé post hoc comparisons (α=.05). Data for surface detail reproduction were analyzed with the Wilcoxon Signed-Rank procedure and gypsum compatibility with the Kruskal-Wallis Rank procedure (α=.05).
  
  
  RESULTS
  The alternative impression materials demonstrated significantly better outcomes with all 3 parameters tested. Disinfection with chloroamine-T did not have any effect on the 3 alternative impression materials. The irreversible hydrocolloid groups produced the most variability in the measurements of linear dimensional change. All of the tested materials were within the ADA's acceptable limit of 1.0% for linear dimensional change, except for the disinfected irreversible hydrocolloid impression material.
  
  
  CONCLUSIONS
  The alternative impression materials performed best for the parameters tested. Spray disinfection had no effect on the alternative impression materials.
authors.affiliation: Department of Restorative Dentistry, LLU School of Dentistry, Loma Linda University, Loma Linda, Calif, USA. msuprono07d@llu.edu
authors.forename: Montry S
authors.initials: MS
authors.lastname: Suprono
authors.forename: Mathew T
authors.initials: MT
authors.lastname: Kattadiyil
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Goodacre
authors.forename: Myron S
authors.initials: MS
authors.lastname: Winer
mesh_terms: D000336:Aerosols; D002133:Calcium Sulfate / Q000737:chemistry*; D002700:Chloramines / Q000737:chemistry; D003102:Colloids / Q000737:chemistry*; D019551:Dental Disinfectants / Q000737:chemistry*; D003760:Dental Impression Materials / Q000737:chemistry*; D004203:Disinfection / Q000379:methods*; D006801:Humans; D008422:Materials Testing; D008853:Microscopy; D003765:Models, Dental / Q000592:standards; D009930:Organic Chemicals / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry; D012833:Siloxanes / Q000737:chemistry; D013499:Surface Properties; D014105:Tosyl Compounds / Q000737:chemistry
chemical_list: D000336:Aerosols; D002700:Chloramines; D003102:Colloids; D019551:Dental Disinfectants; D003760:Dental Impression Materials; D009930:Organic Chemicals; D011145:Polyvinyls; D012833:Siloxanes; D014105:Tosyl Compounds; C016300:chloramine-T; C034183:vinyl polysiloxane; C043594:Jeltrate; D002133:Calcium Sulfate