Evaluation of Heat Transfer during Root Canal Obturation with Thermoplasticized Gutta-percha. Part II. In Vivo Response to Heat Levels Generated

By Gutmann J, Rakusin H, Powe R, Bowles W

Date: 08/1987
Journal: JOE


Purpose: to evaluate the immediate and short-term response of the periodontium to the elevated temperatures of the gutta-percha used in injected thermo-plasticized technique

N= 12 intact posterior dog teeth.

Materials and Methods:

•Pre-operative radiograph take, rubber-dam isolation, teeth accessed and instrument up to #70.

•Incision and placement of Thermistor attached to thermometer over the bone opposing mid root (area of expected injection of GP)

•Obturation with or without sealer. Control teeth were untreated teeth, unfilled teeth, teeth treated with cold lateral.

•As a baseline, heat measurement of the hub and tip plus extruded gutta-percha was recorded every 10 sec for 60 sec.

Most highlighted Results:

•Mean temperature of the gutta-percha extruded from the tip was 63.7ºC. •Maximum temperature elevation recorded within 60 s was 1.1ºC

•Control specimens demonstrated normal cellular integrity and fiber arrangement in the periodontal ligament

•An inflammatory response was not noted in any of the immediate, 24-h, or 72-h control specimens.

•Experimental immediate, 24-h, and 72-h specimens showed a consistent pattern of viable cells throughout the sections examined

•No evidence of inflammatory response.

Clinical significance:

the use of this technique appears to be clinically safe. However, studies which employ a long-term evaluation of the periodontium or which measure true temperature elevations of the periodontal ligament, in vivo, are war- ranted.