title: Nitric oxide in human gingival crevicular fluid after orthodontic force application.
abstract: Nitric oxide (NO) is involved in bone remodelling and has been shown to play a role in regulating the rate of orthodontic tooth movement (OTM) in rat models. In humans, however, the role of NO in OTM remains less clear. In this study, NO concentration in gingival crevicular fluid (GCF) was measured in patients undergoing orthodontic treatment. Thirteen male participants (ages 11-18 years) planned for non-extraction fixed orthodontic therapy were recruited. Samples of GCF were collected from each maxillary central incisor and first and second molar immediately before (T0), 1h after (T1), and 3-4 days after (T2) application of light orthodontic forces. The maxillary second molars were not included in the appliance and served as controls. Measureable NO levels were consistently obtained from all sampled sites. Total NO levels showed significantly higher NO levels (p<0.05) at T1 at the buccal surfaces of the central incisors when compared to the first and second molars. The results indicate a possible role for NO in OTM at the pressure sites of incisors at early time points. Further studies are required to determine whether NO levels in the periodontal ligament tissues of human teeth during OTM are affected by a force gradient and the magnitude of the applied force.
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.
authors.forename: H
authors.initials: H
authors.lastname: Ford
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Suri
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Nilforoushan
authors.affiliation: Dental Research Institute, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Manolson
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada; Dental Research Institute, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada. Electronic address: sg.gong@dentistry.utoronto.ca.
authors.forename: S G
authors.initials: SG
authors.lastname: Gong
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000378:metabolism; D002648:Child; D005883:Gingival Crevicular Fluid / Q000737:chemistry*; D006801:Humans; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism*; D014087:Tooth Movement Techniques / Q000379:methods*
chemical_list: D015415:Biomarkers; D009569:Nitric Oxide
keywords: Biomarkers; Griess reaction; Orthodontic tooth movement; Periodontal ligament; Tissue remodelling/inflammation