title: Effect of cyclic load on vertical misfit of prefabricated and cast implant single abutment.
abstract: OBJECTIVE
  The purpose of this in vitro study was to evaluate misfit alterations at the implant/abutment interface of external and internal connection implant systems when subjected to cyclic loading.
  
  
  METHODS
  Standard metal crowns were fabricated for 5 groups (n=10) of implant/abutment assemblies: Group 1, external hexagon implant and UCLA cast-on premachined abutment; Group 2, internal hexagon implant and premachined abutment; Group 3, internal octagon implant and prefabricated abutment; Group 4, external hexagon implant and UCLA cast-on premachined abutment; and Group 5, external hexagon implant and Ceraone abutment. For groups 1, 2, 3 and 5, the crowns were cemented on the abutments and in group 4 crowns were screwed directly on the implant. The specimens were subjected to 500,000 cycles at 19.1 Hz of frequency and non-axial load of 133 N in a MTS 810 machine. The vertical misfit (μm) at the implant/abutment interface was evaluated before (B) and after (A) application of the cyclic loading. Data were analyzed statistically by using two-away ANOVA and Tukey's post-hoc test (p<0.05).
  
  
  RESULTS
  Before loading values showed no difference among groups 2 (4.33 ± 3.13), 3 (4.79 ± 3.43) and 5 (3.86 ± 4.60); between groups 1 (12.88 ± 6.43) and 4 (9.67 ± 3.08), and among groups 2, 3 and 4. However, groups 1 and 4 were significantly different from groups 2, 3 and 5. After loading values of groups 1 (17.28 ± 8.77) and 4 (17.78 ± 10.99) were significantly different from those of groups 2 (4.83 ± 4.50), 3 (8.07 ± 4.31) and 5 (3.81 ± 4.84). There was a significant increase in misfit values of groups 1, 3 and 4 after cyclic loading, but not for groups 2 and 5.
  
  
  CONCLUSIONS
  The cyclic loading and type of implant/abutment connection may develop a role on the vertical misfit at the implant/abutment interface.
authors: Maranhão University Center (UNICEUMA), São Luis, MA, Brazil.rudysd@uol.com.br
authors: Rudys Rodolfo de
authors: RR
authors: Jesus Tavarez
authors: Wellington Cardoso
authors: WC
authors: Bonachela
authors: Anuar Antônio
authors: AA
authors: Xible
mesh_terms: D000704:Analysis of Variance; D000044:Dental Abutments; D015921:Dental Implants; D017267:Dental Prosthesis Design; D057893:Immediate Dental Implant Loading; D008422:Materials Testing; D017755:Prosthesis Fitting; D013499:Surface Properties; D019415:Torque
chemical_list: D015921:Dental Implants