title: An investigation of the heat induced during ultrasonic post removal.
abstract: The purpose of this study was to investigate the potential for temperature increase along the external root surface during ultrasonic post removal in a simulated clinical environment. Thirty-seven extracted teeth were decoronated, instrumented, and then obturated with gutta-percha and sealer. Post spaces were prepared, followed by cementation of stainless steel posts. A simulated clinical environment was created by using a polymethylmethacrylate sheet with holes custom fitted for the extracted teeth and then suspended over a heated water bath. Two thermocouples were attached at 6 and 12 mm from the top of the post along the external root surface. Teeth were divided into 3 test groups, no coolant, air-cooled, and water-cooled. Temperature changes were recorded by using a Vishay 5000 Strain Smart system. Results demonstrated that a significant difference existed in the average heat rates between the upper and lower thermocouples for no coolant and water-cooled groups at the medium setting and the air-cooled group at the high setting. The average heat rates were significantly different between the 2 thermocouples for all 3 groups when comparing the 2 ultrasonic power settings. Results indicated that the average heat rate was less for the water-cooled group when using a medium power setting.
authors: Department of Endodontics, School of Dentistry, University of Washington, Seattle, Washington 93195, USA.
authors: Christopher A
authors: CA
authors: Ettrich
authors: Paul E
authors: PE
authors: Labossière
authors: David L
authors: DL
authors: Pitts
authors: James D
authors: JD
authors: Johnson
mesh_terms: D000388:Air; D001831:Body Temperature / Q000502:physiology*; D002484:Cementation; D017005:Dental Debonding / Q000295:instrumentation / Q000379:methods*; D006171:Gutta-Percha / Q000627:therapeutic use; D006358:Hot Temperature; D006801:Humans; D011176:Post and Core Technique / Q000295:instrumentation*; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D012389:Root Canal Obturation / Q000379:methods; D018915:Root Canal Preparation / Q000379:methods; D013193:Stainless Steel; D013821:Thermometers; D014092:Tooth Root / Q000503:physiopathology*; D014464:Ultrasonic Therapy / Q000295:instrumentation / Q000379:methods*; D014867:Water
chemical_list: D012387:Root Canal Filling Materials; D014867:Water; D013193:Stainless Steel; D006171:Gutta-Percha