title: The influence of implant abutment surface roughness and the type of cement on retention of implant supported crowns.
abstract: OBJECTIVE
  To provide relative data on the retentive characters of the commonly used cements on different implant abutment surfaces.
  
  
  METHODS
  A total of 20 implant abutments were divided into 2 groups. Ten implants were unaltered and ten were air borne particle abraded with 50μ aluminium oxide. Three luting agents (Tempbond, IRM and ImProv) were used to secure the crowns to abutments. All the crowns were removed from the abutment with an Instron machine at 0.5mm per minute and tensile bond strengths were recorded. Statistical analysis was performed using Anova, Paired t-test and Post-Hoc tests.
  
  
  RESULTS
  IRM showed the highest mean tensile strength among the three cements when used with treated and untreated implant abutment surfaces. Change in the abutment surface roughness had no effect on the mean tensile bond strength of TempBond and IRM cements, whereas ImProv cement showed reduced tensile strength with sandblasted surface.
  
  
  CONCLUSIONS
  When increased retention is required IRM cement with either sandblasted or milled surface could be used and when retrievability is required cements of choice could be either TempBond or ImProv.
authors.affiliation: Professor & HOD, Department of Prosthodontics, MNR Dental College & Hospital , Sangareddy, Telangana, India .
authors.forename: S Varalakshmi
authors.initials: SV
authors.lastname: Reddy
authors.affiliation: Senior Lecturer, Department of Prosthodontics, SVS Institute of Dental Sciences , Mahabubnagar, Telangana, India .
authors.forename: M Sushender
authors.initials: MS
authors.lastname: Reddy
authors.affiliation: Reader, Department of Oral Surgery, KLR Lenora College of Dental Sciences , Rajanagaram, Rajamundry, Andhra Pradesh, India .
authors.forename: C Rajaneesh
authors.initials: CR
authors.lastname: Reddy
authors.affiliation: Reader, Department of Prosthodontics, Sri Balaji Dental College , Moinabad,R.R Dist, Telangana, India .
authors.forename: Padmaja
authors.initials: P
authors.lastname: Pithani
authors.affiliation: Reader, Department of Prosthodontics, AME'S Dental College , Raichur, Karnataka, India .
authors.forename: Santosh Kumar
authors.initials: SK
authors.lastname: R
authors.affiliation: Senior Lecturer, Department of Oral Pathology, Malla Reddy Institute of Dental Sciences , Suraram, Hyderabad, Telangana, India .
authors.forename: Ganesh
authors.initials: G
authors.lastname: Kulkarni
keywords: Aluminum oxide; Dental Cements; Eugenol; Methymethacrylates; Tensile strength