title: In vitro sealing ability of two materials at five different implant-abutment surfaces.
abstract: BACKGROUND
  The aim of the present study was to test the sealing ability of two materials at five different implant-abutment surfaces.
  
  
  METHODS
  In the first phase, 2 mul brain-heart infusion (BHI) broth was deposited into the implant wells and glass culture tubes. A varnish or silicon sealant was applied at the cervical implant portion of experimental groups. The control group remained unexposed. The abutments were torque-tightened to 20 Ncm with a manual torque driver. Implants were immersed in 4 ml BHI broth at 37 degrees C for 2 hours to exclude contamination. In the second phase, 100 mul Enterococcus faecalis American Type Culture Collection (ATCC) strain 29212 was deposited into the glass culture tubes. After periods of 7, 14, 21, 35, 49, and 63 days, the sealing capacity was checked. Abutments were removed, and a sterile paper cone collected material inside implant bodies. This material was transferred to new tubes with BHI to verify the presence of cloudy broths within 24 to 48 hours.
  
  
  RESULTS
  There were no statistically significant differences between the two materials for each time period (Fisher exact test; P >0.05). Group E showed the least level of sealing ability (six implants contaminated), whereas group T showed the highest level (only two implants).
  
  
  CONCLUSIONS
  1) Materials tested were not able to prevent contamination over 63 days. 2) Bacterial contamination was verified after 14 and 35 days in the control and experimental groups, respectively. 3) Although materials tested had demonstrated similar sealing capacities, dental implants showed bacterial contamination regardless of their external or internal hexagonal configurations.
authors.affiliation: Oral Rehabilitation Program, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil.
authors.forename: Antonio R C
authors.initials: AR
authors.lastname: Duarte
authors.forename: Paulo H O
authors.initials: PH
authors.lastname: Rossetti
authors.forename: Leylha M N
authors.initials: LM
authors.lastname: Rossetti
authors.forename: Sergio A
authors.initials: SA
authors.lastname: Torres
authors.forename: Wellington C
authors.initials: WC
authors.lastname: Bonachela
mesh_terms: D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D002710:Chlorhexidine / Q000627:therapeutic use*; D015169:Colony Count, Microbial; D000044:Dental Abutments / Q000382:microbiology*; D003738:Dental Cements / Q000627:therapeutic use*; D015921:Dental Implants / Q000382:microbiology*; D003763:Dental Leakage / Q000517:prevention & control*; D017267:Dental Prosthesis Design; D004129:Dimethylpolysiloxanes / Q000627:therapeutic use*; D004338:Drug Combinations; D013293:Enterococcus faecalis; D012828:Silicones / Q000627:therapeutic use*; D013943:Thymol / Q000627:therapeutic use*
chemical_list: D000891:Anti-Infective Agents, Local; D003738:Dental Cements; D015921:Dental Implants; D004129:Dimethylpolysiloxanes; D004338:Drug Combinations; D012828:Silicones; C079161:chlorhexidine, thymol drug combination; D013943:Thymol; C013830:baysilon; D002710:Chlorhexidine