title: Shear bond strength of brackets on restorative materials: Comparison on various dental restorative materials using the universal primer Monobond® Plus.
abstract: OBJECTIVE
  The purpose of this work was to analyze surfaces consisting of different restorative materials for shear bond strength (SBS) and failure patterns of metal and ceramic brackets. Bonding involved the use of a universal primer (Monobond® Plus, Ivoclar Vivadent).
  
  
  METHODS
  Six restorative materials were tested, including one composite resin (Clearfil Majesty™ Posterior, Kuraray Noritake Dental), one glass-ceramic material (IPS Empress® Esthetic, Ivoclar Vivadent), one oxide-ceramic material (CORiTEC Zr transpa Disc, imes-icore), two base-metal alloys (remanium® star, Dentaurum; Colado® CC, Ivoclar Vivadent), and one palladium-based alloy (Callisto® 75 Pd, Ivoclar Vivadent). Bovine incisors served as controls. Both metal and ceramic brackets (discovery®/discovery® pearl; Dentaurum) were bonded to the restorative surfaces after sandblasting and pretreatment with Monobond® Plus. A setup modified from DIN 13990-2 was used for SBS testing and adhesive remnant index (ARI)-based analysis of failure patterns.
  
  
  RESULTS
  The metal brackets showed the highest mean SBS values on the glass-ceramic material (68.61 N/mm(2)) and the composite resin (67.58 N/mm(2)) and the lowest mean SBS on one of the base-metal alloys (Colado® CC; 14.01 N/mm(2)). The ceramic brackets showed the highest mean SBS on the glass-ceramic material (63.36 N/mm(2)) and the lowest mean SBS on the palladium-based alloy (38.48 N/mm(2)). Significant differences between the metal and ceramic brackets were observed in terms of both SBS values and ARI scores (p < 0.05). Under both bracket types, fractures of the composite-resin and the glass-ceramic samples were observed upon debonding. Opaque restorative materials under metal brackets were found to involve undercuring of the adhesive.
  
  
  CONCLUSIONS
  Monobond® Plus succeeded in generating high bond strengths of both bracket types on all restorative surfaces. Given our observations of cohesive fracture (including cases of surface avulsion) of the composite-resin and the glass-ceramic samples, we recommend against using these material combinations in clinical practice.
authors.affiliation: Department of Orthodontics, University of Erlangen Medical School, Erlangen, Germany. thomasebert@yahoo.com.|Department of Orthodontics and Orofacial Orthopedics, Zahnklinik 3-Kieferorthopädie, Universitätsklinikum Erlangen, Glückstrasse 11, 91054, Erlangen, Germany. thomasebert@yahoo.com.
authors.forename: Thomas
authors.initials: T
authors.lastname: Ebert
authors.affiliation: Department of Orthodontics, University of Erlangen Medical School, Erlangen, Germany.
authors.forename: Laura
authors.initials: L
authors.lastname: Elsner
authors.affiliation: Department of Orthodontics, University of Erlangen Medical School, Erlangen, Germany.
authors.forename: Ursula
authors.initials: U
authors.lastname: Hirschfelder
authors.affiliation: Department of Orthodontics, University of Erlangen Medical School, Erlangen, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Hanke
mesh_terms: D000268:Adhesiveness; D000818:Animals; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry*; D003738:Dental Cements / Q000737:chemistry*; D017267:Dental Prosthesis Design; D019544:Equipment Failure Analysis; D066298:In Vitro Techniques; D007180:Incisor / Q000737:chemistry*; D008422:Materials Testing; D016876:Metal Ceramic Alloys / Q000737:chemistry*; D016910:Orthodontic Brackets; D033081:Shear Strength; D013314:Stress, Mechanical
chemical_list: D003188:Composite Resins; D003738:Dental Cements; D016876:Metal Ceramic Alloys; C076808:Monobond S
keywords: DIN 13990-2; Orthodontic brackets; Orthodontics; Shear bond strength; Universal primer