title: Pulp vitality in patients with intraoral and oropharyngeal malignant tumors undergoing radiation therapy assessed by pulse oximetry.
abstract: BACKGROUND
  The aim of this study was to evaluate pulp oxygenation levels (%SpO(2)) in patients with malignant intraoral and oropharyngeal tumors treated by radiotherapy (RT).
  
  
  METHODS
  Pulp oxygenation levels were measured by pulse oximetry. Twenty patients were selected, and two teeth of each participant (n = 40) were analyzed, regardless of the quadrant and the area irradiated, at four different time points: TP1, before RT; TP2, at the beginning of RT with radiation doses between 30 and 35 Gy; TP3, at the end of RT with radiation doses between 60 and 70 Gy; and TP4, 4 to 5 months after the beginning of cancer treatment.
  
  
  RESULTS
  Mean %SpO(2) at the different time points were 93% (TP1), 83% (TP2), 77% (TP3), and 85% (TP4). The Student's t test showed statistically significant differences between TP1 and TP2 (P < .01), TP3 (P < .01), and TP4 (P < .01). TP3 was also statistically significantly different when compared with TP2 (P < .01) and TP4 (P < .01). No statistically significant difference could be observed between TP2 and TP4.
  
  
  CONCLUSIONS
  Because the mean %SpO(2) before RT was greater than during and after therapy and values obtained 4 to 5 months after the beginning of RT were close to the initiation of RT, pulp tissue may be able to regain normal blood flow after RT. If the changes in the microcirculation of the dental pulp were indeed transitory, preventive endodontic treatment or extraction in patients who are currently undergoing or recently received RT and who show negative signs of pulp sensitivity may not be necessary for pulpal reasons.
authors.affiliation: Discipline of Endodontics, Department of Esthetic Dentistry, School of Dentistry, Universidade de São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Simony Hidee Hamoy
authors.initials: SH
authors.lastname: Kataoka
authors.forename: Frank C
authors.initials: FC
authors.lastname: Setzer
authors.forename: Eudes
authors.initials: E
authors.lastname: Gondim-Junior
authors.forename: Oscar Faciola
authors.initials: OF
authors.lastname: Pessoa
authors.forename: Giulio
authors.initials: G
authors.lastname: Gavini
authors.forename: Celso Luiz
authors.initials: CL
authors.lastname: Caldeira
mesh_terms: D000328:Adult; D017742:Dental Care for Chronically Ill / Q000706:statistics & numerical data*; D003782:Dental Pulp / Q000098:blood supply*; D003791:Dental Pulp Test; D005260:Female; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000528:radiation effects; D008875:Middle Aged; D009959:Oropharyngeal Neoplasms / Q000532:radiotherapy*; D010092:Oximetry; D010100:Oxygen / Q000097:blood; D019553:Tooth, Nonvital / Q000517:prevention & control; D019564:Unnecessary Procedures
chemical_list: D010100:Oxygen