title: Influence of different crosshead speeds on diametral tensile strength of a methacrylate based resin composite: An in-vitro study.
abstract: OBJECTIVE
  The aim was to evaluate the influence of different crosshead speeds on diametral tensile strength (DTS) of a resin composite material (Tetric N-Ceram).
  
  
  METHODS
  The DTS of Tetric N-Ceram was evaluated using four different crosshead speeds 0.5 mm/min (DTS 1), 1 mm/min (DTS 2), 5 mm/min (DTS 3), 10 mm/min (DTS 4). A total of 48 specimens were prepared and divided into four subgroups with 12 specimens in each group. Specimens were made using stainless steel split custom molds of dimensions 6 mm diameter and 3 mm height. The specimens were stored in distilled water at room temperature for 24 h. Universal testing machine was used and DTS values were calculated in MPa.
  
  
  RESULTS
  Analysis of variance was used to compare the four groups. Higher mean DTS value was recorded in DTS 2 followed by DTS 4, DTS 1, and DTS 3, respectively. However, the difference in mean tensile strength between the groups was not statistically significant (P > 0.05).
  
  
  CONCLUSIONS
  The crosshead speed variation between 0.5 and 10 mm/min does not seem to influence the DTS of a resin composite.
authors.affiliation: Department of Conservative Dentistry and Endodontics, Bapuji Dental College and Hospital, Rajeev Gandhi University of Health Sciences, Davangere, Karnataka, India.
authors.forename: Anubhav
authors.initials: A
authors.lastname: Sood
authors.affiliation: Department of Conservative Dentistry and Endodontics, Indira Gandhi Institute of Dental Sciences, Sri Balaji Vidyapeeth University, Pondicherry, India.
authors.forename: Sathyanarayanan
authors.initials: S
authors.lastname: Ramarao
authors.affiliation: Department of Conservative Dentistry and Endodontics, Indira Gandhi Institute of Dental Sciences, Sri Balaji Vidyapeeth University, Pondicherry, India.
authors.forename: Usha
authors.initials: U
authors.lastname: Carounanidy
keywords: Composite resins; crosshead speed; tensile strength