RISK ASSESSMENT OF THE TOXICITY OF SOLVENTS OF GUTTA-PERCHA USED IN ENDODONTIC RETREATMENT

Three randomly assigned groups of single-canaled extracted teeth obtur ated with gutta-percha were retreated using controlled application of one of three organic solvents: chloroform, xylene, or halothane, Two a dditional groups of teeth served as positive and negative controls, Re sidual volume of solvent expressed through the apical foramen during r etreatment was determined by the difference of pretreatment and posttr eatment weights of hermetically sealed receptacles attached to the roo t surface of the teeth, Results indicate that the amount of solvent th at has been determined to have leached out through the apical foramen is several orders of magnitude below the permissible toxic dose, Thus, it is proposed that the use of any of the aforementioned solvents use d in the retreatment of root canals would pose negligible risk to the patient.