title: Assessment of tissue oxygenation of periodontal inflammation in patients with coronary artery diseases using optical spectroscopy.
abstract: BACKGROUND
  We have recently developed a non-invasive periodontal diagnostic tool that was validated in periodontitis patients without systemic disorders like coronary artery disease (CAD). The purpose of present study is to verify whether this optical instrument can also be used in periodontitis patients with CAD.
  
  
  METHODS
  A total of 62 periodontitis patients with CAD were recruited along with a control group consisting of 59 age and gender matched periodontitis volunteers without systemic disorders. Using a portable optical near-infrared spectrometer, optical spectra were obtained, processed and evaluated from the two groups. A modified Beer-Lambert unmixing model that incorporates a nonparametric scattering loss function was used to determine the relative contribution of deoxygenated hemoglobin (Hb) and oxygenated hemoglobin (HbO2) to the overall spectrum. The balance between tissue oxygen delivery and utilization in periodontal tissues was then assessed.
  
  
  RESULTS
  Tissue oxygen saturation was significantly decreased in the periodontitis sites (p < 0.01), compared to the healthy sites in those individuals with CAD. There was a trend towards increased concentration of Hb and decreased concentration of HbO2 from healthy to diseased sites, without statistical significance (p > 0.05). No statistical differences were found in tissue oxygen saturation between the CAD and control groups either in periodontal healthy or inflammatory sites.
  
  
  CONCLUSIONS
  This study supports the hypothesis that optical spectroscopy can determine the periodontal inflammation in patients with certain systemic disorders like CAD. And the overall periodontal oxygenation profiles in CAD patients resemble those in non-CAD individuals either in healthy or inflammatory sites.
authors.forename: Chunyang
authors.initials: C
authors.lastname: Zhang
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Xiang
authors.forename: Minqi
authors.initials: M
authors.lastname: Xu
authors.forename: Chun
authors.initials: C
authors.lastname: Fan
authors.forename: Michael G
authors.initials: MG
authors.lastname: Sowa
authors.affiliation: Medical Devices Portfolio, National Research Council of Canada, 435 Ellice Ave,, Winnipeg, MB R3B 1Y6, Canada. kan-zhi.liu@nrc-cnrc.gc.ca.
authors.forename: Kan-Zhi
authors.initials: KZ
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D055113:Chronic Periodontitis / Q000175:diagnosis / Q000378:metabolism*; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000378:metabolism*; D005260:Female; D005891:Gingivitis / Q000378:metabolism; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D055100:Optical Fibers; D061848:Optical Imaging / Q000295:instrumentation; D010101:Oxygen Consumption / Q000502:physiology*; D010108:Oxyhemoglobins / Q000378:metabolism; D017622:Periodontal Attachment Loss / Q000378:metabolism; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000378:metabolism; D010518:Periodontitis / Q000378:metabolism; D010519:Periodontium / Q000378:metabolism; D015203:Reproducibility of Results; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation / Q000379:methods
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; C100003:deoxyhemoglobin