title: Cleaning potential of glycine air-flow application in an in vitro peri-implantitis model.
abstract: OBJECTIVE
  The study aimed to assess the accessibility of a glycine powder blasting device to implant surfaces in models imitating different peri-implantitis defects. The null hypothesis was that the device allows for complete surface decontamination in all defect types.
  
  
  METHODS
  Eighteen implants were dip-coated and placed in resin blocks with different defect morphologies. Vertical bone angulations of 90°, 60°, 30° and 15° were chosen and the implants were treated for 10 s using an air-flow device employing glycine powder. Once removed, photographs from the implants were taken in three directions: perpendicularly (90°) to the implant axis and with an angulation of 60° and 120°, the latter ones to assess the coronal and apical thread areas. The area with residual color represented areas, which were not accessible to the powder. This area was planimetrically assessed. Medians and inter-quartile ranges (IQR) of the percentage of uncleaned surfaces were calculated and nonparametric paired and unpaired statistical analyses were performed.
  
  
  RESULTS
  The median percentages (IQR in brackets) of uncleaned areas in the 90°, 60°, 30° and 15° defects were of 3%(A) (6), 8%(A) (4), 24%(B) (8), and 51%(C) (13), respectively (different superscript capital letters represent statistically significant differences; P < 0.0001). The upper aspects of the threads (coronal faces) were significantly better cleaned than the lower ones (P < 0.001). This finding was more pronounced in narrower defects.
  
  
  CONCLUSIONS
  Although a complete surface decontamination could not be performed in any of the defects, the biggest part of the surface could be cleaned in the larger defects. Especially in narrow defects and under the threads, residually stained areas remain on the implant surfaces.
authors.affiliation: Clinic of Preventive Dentistry, Periodontology and Cariology, Center of Dental and Oral Medicine and Maxillofacial Surgery, University of Zurich, Zürich, Switzerland. philipp.sahrmann@zzm.uzh.ch
authors.forename: Philipp
authors.initials: P
authors.lastname: Sahrmann
authors.forename: Valerie
authors.initials: V
authors.lastname: Ronay
authors.forename: Beatrice
authors.initials: B
authors.lastname: Sener
authors.forename: Ronald E
authors.initials: RE
authors.lastname: Jung
authors.forename: Thomas
authors.initials: T
authors.lastname: Attin
authors.forename: Patrick R
authors.initials: PR
authors.lastname: Schmidlin
mesh_terms: D020906:Air Abrasion, Dental / Q000379:methods*; D003666:Decontamination / Q000379:methods*; D015921:Dental Implants; D004866:Equipment Contamination / Q000517:prevention & control*; D005998:Glycine / Q000494:pharmacology*; D066298:In Vitro Techniques; D057873:Peri-Implantitis / Q000517:prevention & control*; D010781:Photography; D011208:Powders; D013499:Surface Properties
chemical_list: D015921:Dental Implants; D011208:Powders; D005998:Glycine