title: Surface hardness evaluation of different composite resin materials: influence of sports and energy drinks immersion after a short-term period.
abstract: OBJECTIVE
  This study evaluated the effect of sports and energy drinks on the surface hardness of different composite resin restorative materials over a 1-month period.
  
  
  METHODS
  A total of 168 specimens: Compoglass F, Filtek Z250, Filtek Supreme, and Premise were prepared using a customized cylindrical metal mould and they were divided into six groups (N=42; n=7 per group). For the control groups, the specimens were stored in distilled water for 24 hours at 37°C and the water was renewed daily. For the experimental groups, the specimens were immersed in 5 mL of one of the following test solutions: Powerade, Gatorade, X-IR, Burn, and Red Bull, for two minutes daily for up to a 1-month test period and all the solutions were refreshed daily. Surface hardness was measured using a Vickers hardness measuring instrument at baseline, after 1-week and 1-month. Data were statistically analyzed using Multivariate repeated measure ANOVA and Bonferroni's multiple comparison tests (α=0.05).
  
  
  RESULTS
  Multivariate repeated measures ANOVA revealed that there were statistically significant differences in the hardness of the restorative materials in different immersion times (p<0.001) in different solutions (p<0.001). The effect of different solutions on the surface hardness values of the restorative materials was tested using Bonferroni's multiple comparison tests, and it was observed that specimens stored in distilled water demonstrated statistically significant lower mean surface hardness reductions when compared to the specimens immersed in sports and energy drinks after a 1-month evaluation period (p<0.001). The compomer was the most affected by an acidic environment, whereas the composite resin materials were the least affected materials.
  
  
  CONCLUSIONS
  The effect of sports and energy drinks on the surface hardness of a restorative material depends on the duration of exposure time, and the composition of the material.
authors.affiliation: Department of Operative Dentistry, School of Dentistry, Istanbul University, Istanbul, Turkey. uerdemir@hotmail.com
authors.forename: Ugur
authors.initials: U
authors.lastname: Erdemir
authors.forename: Esra
authors.initials: E
authors.lastname: Yildiz
authors.forename: Meltem Mert
authors.initials: MM
authors.lastname: Eren
authors.forename: Sevda
authors.initials: S
authors.lastname: Ozel
mesh_terms: D000704:Analysis of Variance; D003188:Composite Resins / Q000737:chemistry*; D061215:Energy Drinks; D005899:Glass Ionomer Cements / Q000737:chemistry; D006245:Hardness Tests; D006801:Humans; D008422:Materials Testing; D013499:Surface Properties / Q000187:drug effects; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: C105428:Compoglass; D003188:Composite Resins; C474035:Filtek Supreme; C444701:Filtek Z250; D005899:Glass Ionomer Cements; C507210:premise composite resin; D014867:Water