title: The Impact of Expasyl® Gingival Retraction Paste on the Bond Strength of Self-etch and Total-etch Systems.
abstract: To evaluate the influence of Expasyl® gingival retraction paste on the shear bond strength of self-etch and total-etch adhesive systems.
  
  
  
  Twenty-four specimens of extracted, caries-free, sound human molars were used in this study. The molars were then cut vertically into halves through the buccal and lingual cusps. Forty-eight specimens were divided into four groups (total-etch, total-etch with Expasyl application, self-etch, self-etch with Expasyl application) and the shear bond strength was tested.
  
  
  
  Expasyl significantly reduced the shear bond strength of the self-etch and total-etch adhesive systems. The self-etch system showed relatively lower performance compared with the total-etch adhesive system. The shear bond strength values of the total-etch adhesive without Expasyl showed the highest bond strength (21.48 ± 2.89), while the self-etching group adhesive treated with Expasyl showed the lowest shear bond strength value (14.89 ± 1.81).
  
  
  
  From the observations of this in vitro study, it can be concluded that the use of Expasyl® gingival retraction system can negatively affect bond strength of adhesives. The total-etch system showed better compatibility to the Expasyl gingival retraction system than the self-etch.
authors.affiliation: Associate Professor, Department of Prosthetic Dental Sciences College of Dentistry, King Saud University, Post Box: 60169 Riyadh-11545, Saudi Arabia, Fax: +9661-467-9017, e-mail: ksucod@gmail.com.
authors.forename: Abdulaziz M A
authors.initials: AM
authors.lastname: Al Baker
authors.affiliation: Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Alaa
authors.initials: A
authors.lastname: El Araby
authors.affiliation: Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Mohammad D
authors.initials: MD
authors.lastname: Al Amri
authors.affiliation: Department of Periodontics and Community Dentistry, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Anil
authors.initials: A
authors.lastname: Sukumaran
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D001252:Astringents / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003764:Dental Materials / Q000737:chemistry; D003804:Dentin / Q000648:ultrastructure; D060745:Gingival Retraction Techniques; D006801:Humans; D008422:Materials Testing; D010756:Phosphoric Acids / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013314:Stress, Mechanical
chemical_list: D001252:Astringents; D003188:Composite Resins; D003764:Dental Materials; D010756:Phosphoric Acids; D011109:Polymethacrylic Acids; C425843:Prime and Bond NT; D019279:Resin Cements; C121818:Tetric ceram; C030242:phosphoric acid
keywords: Self-etch; Total-etch; Bond strength; Gingival retraction; Expasyl®.