title: The effect of two different coatings on the surface integrity and softness of a tissue conditioner.
abstract: BACKGROUND
  When they are used to treat inflamed, irritated, or distorted tissues or in implant therapy, tissue conditioners are required to function over relatively long time periods. Most presently available materials have a short life span (3 to 4 days).
  
  
  OBJECTIVE
  This study evaluated the effects of 2 different coatings on the surface integrity and softness of a tissue conditioner over a 4-week period.
  
  
  METHODS
  Ten subjects with a complete maxillary denture and a functioning mandibular dentition were included in the study. Each maxillary denture had 3 troughs filled with a tissue conditioner (Coe Comfort). One trough was coated with Monopoly and one with Permaseal; the third trough was left uncoated (control). The specimens were tested at insertion and at 1 week, 2 weeks, and 4 weeks post-insertion for softness with a durometer and for surface integrity with a scanning electron microscope. Statistical differences were determined with analysis of variance (P<.05).
  
  
  RESULTS
  At the end of 4 weeks, the mean and standard deviation of softness on the ASTM scale was 85.1 (4.2) for the control, 81.6 (3.9) for Monopoly, and 77.9 (5.0) for Permaseal. The difference between the control and Permaseal was significant (P<.0042). Qualitatively, SEM analysis indicated that the control deteriorated by the end of the first week, whereas both Monopoly and Permaseal coatings remained intact for up to 2 weeks. All groups showed some conditioner deterioration by 4 weeks. The tissues under the denture-bearing areas remained healthy during the study period.
  
  
  CONCLUSIONS
  Within the limitations of this study, the application of Permaseal or Monopoly coatings significantly reduced the loss of tissue conditioner softness. Permaseal-coated conditioner remained the softest over the length of the study.
authors.affiliation: Division of General Dentistry, Advanced Education in General Dentistry Program, Eastman Dental Center, University of Rochester, Rochester, NY 14620-2989, USA. hans_malmstrom@urmc.rochester.edu
authors.forename: Hans S
authors.initials: HS
authors.lastname: Malmström
authors.forename: Nomita
authors.initials: N
authors.lastname: Mehta
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Sanchez
authors.forename: Mark E
authors.initials: ME
authors.lastname: Moss
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D020099:Coated Materials, Biocompatible; D003822:Denture Liners; D003827:Denture, Complete, Upper; D005260:Female; D006244:Hardness; D006801:Humans; D008297:Male; D008875:Middle Aged; D010795:Phthalic Acids / Q000737:chemistry*; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D014016:Tissue Conditioning, Dental / Q000379:methods*; D014783:Viscosity
chemical_list: D000180:Acrylic Resins; D020099:Coated Materials, Biocompatible; D010795:Phthalic Acids; D013501:Surface-Active Agents; C043685:Coe Comfort