title: A new portable vibrator for plaster pouring: effect on the marginal fit at cylinder-abutment.
abstract: OBJECTIVE
  The aim of this study was to test a new portable vibrator for plaster pouring (developed for this purpose), comparing the effect of its use on the accuracy of working cast of implant-supported restorations to the conventional vibrator.
  
  
  METHODS
  From a master cast with 2 implants, 30 transfer moldings were made randomly and divided into three groups: group I (GI): pouring performed in an outsourced dental laboratory with conventional plaster vibrator (10 casts), group II (GII): pouring performed in the laboratory of the Federal University of Santa Catarina (UFSC) with conventional plaster vibrator (10 casts) and group III (GIII): pouring performed with the portable vibrator fabricated for this study (10 casts). The position of the analogue and marginal adaptation of the infrastructure were verified by testing the single screw on the master model and on the working model. The measurement of misfit was blindly performed with a precision microscope and analyzing unit, Quadra-Check 200. The data were statistically analyzed by analysis of variance (ANOVA) and the Holm-Sidak test (α=0.05).
  
  
  RESULTS
  Means±standard deviations were as follows: GI: 19.19±4.73 µm; GII: 21.72±5.41 µm; GIII: 13.5±2.39 µm (P<0.05), with GIII significantly lower as compared to the other groups.
  
  
  CONCLUSIONS
  Within the limitations of this study, it was concluded that a greater accuracy of working cast was achieved when a portable vibrator was used for casting molds.
authors.affiliation: Department of Implant Dentistry, Federal University of Santa Catarina, Florianópolis, SC, Brazil. pam_ribas@yahoo.com.br
authors.forename: Pâmela Cândida Aires Ribas de
authors.initials: PC
authors.lastname: Andrade
authors.forename: Leonardo Flores
authors.initials: LF
authors.lastname: Luthi
authors.forename: Kyle
authors.initials: K
authors.lastname: Stanley
authors.forename: Antônio Carlos
authors.initials: AC
authors.lastname: Cardoso
mesh_terms: D002133:Calcium Sulfate; D000044:Dental Abutments; D003735:Dental Casting Technique / Q000295:instrumentation*; D003760:Dental Impression Materials; D003761:Dental Impression Technique; D018772:Dental Marginal Adaptation; D019094:Dental Prosthesis, Implant-Supported / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D008422:Materials Testing; D003765:Models, Dental; D011897:Random Allocation; D015203:Reproducibility of Results; D014099:Toothbrushing / Q000295:instrumentation; D014732:Vibration
chemical_list: D003760:Dental Impression Materials; D002133:Calcium Sulfate