Effect of storage solution on surface roughness of provisional crown and fixed partial denture materials.
OBJECTIVE
This study evaluated the surface roughness of polished provisional materials at baseline and after storage in artificial saliva and artificial saliva-coffee solutions.


METHODS
Ten specimens (25 mm x 25 mm x 2 mm) of 12 commercially available provisional crown materials (5 methacrylate and 7 bis-acryl resins) were fabricated and polished. Baseline surface roughness measurements (Ra) were made using a surface roughness tester. Specimens were divided into 2 groups and stored in artificial saliva or artificial saliva-coffee solution at 37 degrees C for 2 weeks. Baseline surface roughness data were analyzed using the analysis of variance; multiple comparisons adjustment was made using the Tukey method. Multiple linear regression methods were used to analyze change in roughness relative to baseline and to assess the impact of storage medium, material, and baseline roughness on this change, including potential interactions among these 3 factors; descriptors of poststorage surface roughness were obtained.


RESULTS
Alike demonstrated the greatest surface roughness, both at baseline and after storage (p <0.05 after adjustment for all Pairwise comparison by Tukey method). Temphase, Temporary Bridge Resin, Instatemp, Unifast, Jet, and Zeta had the lowest baseline surface roughness measurements. The lowest poststorage roughness scores were associated with Protemp Garant, Jet, and Integrity. Five materials (Protemp Garant, Instatemp, Unifast, Jet, and Zeta), formed the group having the lowest rough poststorage outcomes. The data provided strong evidence of a material effect (p <0.0001) at baseline. Evaluation of change in Ra following storage indicated that surface roughness increased for the majority of materials after storage in a moist environment, and that provisional crown materials that exhibit less initial surface roughness tend to undergo greater surface roughness change in a moist environment. Strong indications were found that the effect of the type of storage solution used differed among the materials.


CONCLUSIONS
There were significant differences in surface roughness of provisional crown materials when polished under the same conditions. Methacrylate resins in general exhibited smoother surfaces after initial polishing. Surface roughness increased for nearly all materials after storage in either moist environment.
Haselton
Debra R
DR
Department of General Practice, VCU School of Dentistry, Richmond, VA 23298, USA. drhaselton@vcu.edu
Diaz-Arnold
Ana M
AM
Dawson
Deborah V
DV
D003069:Coffee / Q000009:adverse effects*; D003794:Dental Restoration, Temporary; D016014:Linear Models; D012464:Saliva, Artificial / Q000009:adverse effects*; D013499:Surface Properties
D003069:Coffee; D012464:Saliva, Artificial