title: Influence of dentin and enamel pretreatment with acidic sulfur compounds on adhesive performance.
abstract: OBJECTIVE
  This study tested the potential hampering effects of acidic sulfur compounds (ASC) containing hydroxybenzene sulfonic acid, hydroxymethoxybenzene sulfonic acid, and sulfuric acid, prior to self-etch and etch-and-rinse bonding procedures on enamel and dentin. According to the manufacturer, ASC should be applied after cavity preparation and prior to application of a primer in order to reduce the remaining biofilm in the preparation cavity. Despite promoted marketing, data on the investigated liquid are almost completely lacking.
  
  
  METHODS
  One hundred and fifty-two extracted mandibular bovine incisors were embedded and polished to expose either enamel (E) or dentin (D). Then, specimens were randomly divided and conditioned as follows (n = 12/group): ASC and consecutive phosphoric acid application (E1/D1), ASC (E2/D2; E5/D5), phosphoric acid (E3/D3), and no conditioning (E4/D4; E6/D6). Groups were then treated with either Optibond FL(®) (etch-and-rinse; 1-4) or Clearfil SE Bond(®) (self-etch; 5-6). Hollow acrylic cylinders were bonded with a hybrid composite resin (Filtek Supreme XTE®) to the specimens, and the shear bond strength was measured (1 mm/min). In addition, failure types were assessed. Descriptive statistics and statistical analyses were performed with one-way ANOVA followed by the Scheffé post hoc test.
  
  
  RESULTS
  For enamel, the highest shear bond strength values were obtained applying routine bonding procedures (23.5 ± 5.6 MPa for etch-and-rinse and 26.0 ± 6.0 MPa for self-etch, respectively). In contrast, dentin pretreatment with a combination of ASC and phosphoric acid led to the highest shear bond values (22.8 ± 4.1 MPa).
  
  
  CONCLUSIONS
  This study shows that ASC prior to dental restoration placement cannot be recommended for etch-and-rinse procedures on enamel but is appropriate for dentin without interfering with routine bonding procedures.
  
  
  CONCLUSIONS
  The application of acidic sulfur compounds prior to adhesive restoration placement should be restricted to dentin only as it may negatively influence shear bond strength on sound enamel.
authors.affiliation: Clinic for Preventive Dentistry, Periodontology and Cariology, Center of Dental Medicine, University of Zurich, Plattenstrasse 11, 8032, Zurich, Switzerland.
authors.forename: Alexis
authors.initials: A
authors.lastname: Ioannidis
authors.forename: Bogna
authors.initials: B
authors.lastname: Stawarczyk
authors.forename: Beatrice
authors.initials: B
authors.lastname: Sener
authors.forename: Thomas
authors.initials: T
authors.lastname: Attin
authors.forename: Patrick R
authors.initials: PR
authors.lastname: Schmidlin
mesh_terms: D000143:Acids; D003738:Dental Cements / Q000737:chemistry*; D003743:Dental Enamel; D003804:Dentin / Q000737:chemistry*; D013455:Sulfur / Q000008:administration & dosage*
chemical_list: D000143:Acids; D003738:Dental Cements; D013455:Sulfur