title: Assessment of the safety of two ozone delivery devices.
abstract: OBJECTIVE
  To evaluate the safety of an ozone gas device designed for use in dentistry.
  
  
  METHODS
  Two commercially available ozone applicators, Ozi-cure and HealOzone were used in a clinical simulation using a phantom head while recordings of ozone levels were made in pharyngeal and nasal regions of the patient and near the mouth of the operator. Clinical simulations included ozone application for caries management and endodontic treatment. Recordings were made five times with different levels of suction to assess the effect on ozone levels.
  
  
  RESULTS
  The results with Ozi-cure on caries mode resulted in a peak ozone level in the pharynx of 1.33+/-0.52 ppm when no suction was used. The use of suction nearby reduced the ozone level to zero while suction on the opposite side of the mouth reduced the level to 0.22+/-0.04 ppm. Used on endodontic mode the peak ozone level in the pharynx was 5.51+/-1.63 ppm when no suction was used. The use of suction nearby reduced the ozone level to zero while suction on the opposite side of the mouth reduced the level to 0.84+/-0.54 ppm. Recordings in the patient's nasal region gave a peak of 0.22 ppm when using the Ozi-cure on endodontic mode with no suction. At the operator's mouth the ozone level did not exceed 0.01 ppm although the characteristic smell of ozone was detectable. All recordings with HealOzone were zero. Concentrations of 15 ppm were recorded in a simulated tooth cavity with Ozi-cure and >20 ppm with HealOzone.
  
  
  CONCLUSIONS
  The Ozi-cure device when used without adequate suction allows ozone to be reach a concentration above permitted levels and therefore should not be used. The HealOzone was safe to use.
authors.affiliation: Primary Care Dentistry, King's College London Dental Institute at Guy's, King's College & St. Thomas' Hospitals, Caldecot Road, London SE5 9RW, UK. brian.millar@kcl.ac.uk
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Millar
authors.forename: Nicholas
authors.initials: N
authors.lastname: Hodson
mesh_terms: D000393:Air Pollutants / Q000032:analysis; D000395:Air Pollutants, Occupational / Q000032:analysis; D016902:Air Pollution, Indoor / Q000032:analysis; D000891:Anti-Infective Agents, Local / Q000008:administration & dosage* / Q000032:analysis; D003731:Dental Caries / Q000628:therapy; D003748:Dental Equipment; D004867:Equipment Design; D004869:Equipment Safety; D006801:Humans; D008348:Manikins; D009055:Mouth; D009666:Nose; D010126:Ozone / Q000008:administration & dosage* / Q000032:analysis; D010614:Pharynx; D012390:Root Canal Therapy; D013396:Suction
chemical_list: D000393:Air Pollutants; D000395:Air Pollutants, Occupational; D000891:Anti-Infective Agents, Local; D010126:Ozone