title: Evaluation of the Shear Bond Strength of Composite Resin to Wet and Dry Enamel Using Dentin Bonding Agents Containing Various Solvents.
abstract: BACKGROUND
  Bonding of composite resin to dentin mandates a wet substrate whereas, enamel should be dry. This may not be easily achievable in intracoronal preparations where enamel and dentin are closely placed to each other. Therefore, Dentin Bonding Agents (DBA) are recommended for enamel and dentinal bonding, where enamel is also left moist. A research question was raised if the "enamel-only" preparations will also benefit from wet enamel bonding and contemporary DBA.
  
  
  OBJECTIVE
  The aim of this study was to compare the shear bond strengths of composite resin, bonded to dry and wet enamel using fifth generation DBA (etch and rinse system) containing various solvents such as ethanol/water, acetone and ethanol.
  
  
  METHODS
  The crowns of 120 maxillary premolars were split into buccal and lingual halves. They were randomly allocated into four groups of DBA: Group 1-water/ethanol based, Group 2-acetone based, Group 3-ethanol based, Group 4-universal bonding agent (control group). The buccal halves and lingual halves were bonded using the wet bonding and dry bonding technique respectively. After application of the DBAs and composite resin build up, shear bond strength testing was done.
  
  
  RESULTS
  Group 1 (ethanol/water based ESPE 3M, Adper Single Bond) showed highest bond strength of (23.15 MPa) in dry enamel. Group 2 (acetone based Denstply, Prime and Bond NT, showed equal bond strength in wet and dry enamel condition (18.87 MPa and 18.02 MPa respectively).
  
  
  CONCLUSIONS
  Dry enamel bonding and ethanol/water based etch and rinse DBA can be recommended for "enamel-only" tooth preparations.
authors.affiliation: Professor, Department of Conservative Dentistry and Endodontics, Indira Gandhi Institute of Dental Sciences , Puducherry, India .
authors.forename: Carounanidy
authors.initials: C
authors.lastname: Usha
authors.affiliation: Professor and Head, Department of Conservative Dentistry and Endodontics, Indira Gandhi Institute of Dental Sciences , Puducherry, India .
authors.forename: Sathyanarayanan
authors.initials: S
authors.lastname: Ramarao
authors.affiliation: Reader, Department of Conservative Dentistry and Endodontics, Indira Gandhi Institute of Dental Sciences , Puducherry, India .
authors.forename: Bindu Meera
authors.initials: BM
authors.lastname: John
authors.affiliation: Senior Lecturer, Department of Conservative Dentistry and Endodontics, Indira Gandhi Institute of Dental Sciences , Puducherry, India .
authors.forename: Praveen
authors.initials: P
authors.lastname: Rajesh
authors.affiliation: Postgraduate Student, Department of Conservative Dentistry and Endodontics, Indira Gandhi Institute of Dental Sciences , Puducherry, India .
authors.forename: S
authors.initials: S
authors.lastname: Swatha
keywords: Dry enamel bonding; Enamel-only; Wet bonding