title: Minimal alterations on the enamel surface by micro-abrasion: in vitro roughness and wear assessments.
abstract: OBJECTIVE
  To evaluate the in vitro changes on the enamel surface after a micro-abrasion treatment promoted by different products.
  
  
  METHODS
  Fifty (50) fragments of bovine enamel (15 mm × 5 mm) were randomly assigned to five groups (n=10) according to the product utilized: G1 (control)= silicone polisher (TDV), G2= 37% phosphoric acid (3M/ESPE) + pumice stone (SS White), G3= Micropol (DMC Equipment), G4= Opalustre (Ultradent) and G5= Whiteness RM (FGM Dental Products). Roughness and wear were the responsible variables used to analyze these surfaces in four stages: baseline, 60 s and 120 s after the micro-abrasion and after polishing, using a Hommel Tester T1000 device. After the tests, a normal distribution of data was verified, with repeated ANOVA analyses (p≤0.05) which were used to compare each product in different stages. One-way ANOVA and Tukey tests were applied for individual comparisons between the products in each stage (p≤0.05).
  
  
  RESULTS
  Means and standard deviations of roughness and wear (µm) after all the promoted stages were: G1=7.26(1.81)/13.16(2.67), G2=2.02(0.62)/37.44(3.33), G3=1.81(0.91)/34.93(6.92), G4=1.92(0.29)/38.42(0.65) and G5=1.98(0.53)/33.45(2.66). At 60 seconds, all products tended to produce less surface roughness with a variable gradual decrease over time. After polishing, there were no statistically significant differences between the groups, except for G1. Independent of the product utilized, the enamel wear occurred after the micro-abrasion.
  
  
  CONCLUSIONS
  In this in vitro study, enamel micro-abrasion presented itself as a conservative approach, regardless of the type of the paste compound utilized. These products promoted minor roughness alterations and minimal wear. The use of phosphoric acid and pumice stone showed similar results to commercial products for the micro-abrasion with regard to the surface roughness and wear.
authors.affiliation: Department of Operative Dentistry, Dental Materials and Endodontics, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Marcela Charantola
authors.initials: MC
authors.lastname: Rodrigues
authors.forename: Rafael Francisco Lia
authors.initials: RF
authors.lastname: Mondelli
authors.forename: Gabriela Ulian
authors.initials: GU
authors.lastname: Oliveira
authors.forename: Eduardo Batista
authors.initials: EB
authors.lastname: Franco
authors.forename: Wagner
authors.initials: W
authors.lastname: Baseggio
authors.forename: Linda
authors.initials: L
authors.lastname: Wang
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002417:Cattle; D003743:Dental Enamel / Q000187:drug effects; D003764:Dental Materials; D019243:Enamel Microabrasion / Q000379:methods*; D008422:Materials Testing; D015203:Reproducibility of Results; D013499:Surface Properties; D013997:Time Factors; D057085:Tooth Wear / Q000139:chemically induced
chemical_list: D003764:Dental Materials