title: Diametral tensile strength and film thickness of an experimental dental luting agent derived from castor oil.
abstract: The need to develop new dental luting agents in order to improve the success of treatments has greatly motivated research.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the diametral tensile strength (DTS) and film thickness (FT) of an experimental dental luting agent derived from castor oil (COP) with or without addition of different quantities of filler (calcium carbonate - CaCO3).
  
  
  METHODS
  Eighty specimens were manufactured (DTS N=40; FT N=40) and divided into 4 groups: Pure COP; COP 10%; COP 50% and zinc phosphate (control). The cements were mixed according to the manufacturers' recommendations and submitted to the tests. The DTS test was performed in the MTS 810 testing machine (10 KN, 0.5 mm/min). For FT test, the cements were sandwiched between two glass plates (2 cm²) and a load of 15 kg was applied vertically on the top of the specimen for 10 min. The data were analyzed by means of one-way ANOVA and Tukey's test (α=0.05).
  
  
  RESULTS
  The values of DTS (MPa) were: Pure COP- 10.94 ± 1.30; COP 10%- 30.06 ± 0.64; COP 50%- 29.87 ± 0.27; zinc phosphate- 4.88 ± 0.96. The values of FT (µm) were: Pure COP- 31.09 ± 3.16; COP 10%- 17.05 ± 4.83; COP 50%- 13.03 ± 4.83; Zinc Phosphate- 20.00 ± 0.12. One-way ANOVA showed statistically significant differences among the groups (DTS - p=1.01E-40; FT - p=2.4E-10).
  
  
  CONCLUSIONS
  The experimental dental luting agent with 50% of filler showed the best diametral tensile strength and film thickness.
authors.affiliation: Department of Dental Materials and Prosthodontics, Araraquara Dental School, Univ. Estadual Paulista, Araraquara, SP, Brazil.
authors.forename: Juliana Cabrini
authors.initials: JC
authors.lastname: Carmello
authors.forename: Laiza Maria Grassi
authors.initials: LM
authors.lastname: Fais
authors.forename: Lígia Nunes de Moraes
authors.initials: LN
authors.lastname: Ribeiro
authors.forename: Salvador
authors.initials: S
authors.lastname: Claro Neto
authors.forename: Dalton Geraldo
authors.initials: DG
authors.lastname: Guaglianoni
authors.forename: Lígia Antunes Pereira
authors.initials: LA
authors.lastname: Pinelli
mesh_terms: D000704:Analysis of Variance; D002119:Calcium Carbonate / Q000737:chemistry; D002368:Castor Oil / Q000737:chemistry*; D003738:Dental Cements / Q000737:chemistry*; D003764:Dental Materials; D003799:Dental Stress Analysis; D006801:Humans; D008422:Materials Testing; D013718:Tensile Strength
chemical_list: D003738:Dental Cements; D003764:Dental Materials; D002368:Castor Oil; D002119:Calcium Carbonate