title: Laser-induced thermal events in empty and pulp-filled dental pulp chambers.
abstract: OBJECTIVE
  The purpose of this investigation was to evaluate: 1. thermal events during laser irradiation @2.1 microns of the pulp; 2. whether these effects are adequately modeled using an empty pulp chamber/root canal.
  
  
  METHODS
  In extracted human teeth, pulpal access was prepared and thermocouples placed 2, 3 mm apical to the center of the irradiation spot. Pulp-filled or empty pulp chambers were irradiated using a Ho:YAG laser: Spot Size: 1 mm; Power: 1, 2, 3.5, 4.5 W; PRR: 5, 12 Hz;
  
  
  METHODS
  10 sec. Thermal measurements were repeated 3x.
  
  
  RESULTS
  Thermal trends did not differ significantly and correlated positively with power (P < 0.01), PRR (P < 0.01), irradiation duration (P < 0.05). No significant difference was determined between temperatures in empty and pulp-filled chambers at all parameters at 5 Hz and at 1-2 W at 12 Hz (P < 0.05, 2-tailed Student's t-test). At 12 Hz and > 3.5 W, pulp chamber temperatures exceeded those in pulpal tissue (P < 0.05).
  
  
  CONCLUSIONS
  Pulp tissues must be present to ensure clinical relevance of thermal measurements.
authors.affiliation: Beckman Laser Institute and Medical Clinic, University of California, Irvine 92612, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Chang
authors.forename: P
authors.initials: P
authors.lastname: Wilder-Smith
mesh_terms: D000818:Animals; D001831:Body Temperature; D003782:Dental Pulp; D003786:Dental Pulp Cavity / Q000601:surgery*; D004285:Dogs; D006358:Hot Temperature; D006801:Humans; D053685:Laser Therapy; D011670:Pulpectomy; D012390:Root Canal Therapy; D012449:Safety