INCIDENCE OF INVASIVE CERVICAL RESORPTION IN BLEACHED ROOT-FILLED TEETH

Invasive cervical resorption, a form of external root resorption, has been reported to be associated with intra-coronal bleaching of root-fi lled teeth and this has raised concerns about carrying out such bleach ing procedures. The purpose of the present study was to examine the in cidence of invasive cervical resorption in root-filled teeth which had been bleached using a standardized technique. Three observers examine d records and radiographs from a total of 158 patients, whose bleachin g treatment had been carried out in a specialist endodontic practice. The sample comprised 204 teeth with a review period of between 1 and 1 9 years. One-hundred-and-fifty-one teeth (77.94 per cent) had an assoc iated history of traumatic injury. All teeth had been treated with a c ombination of thermocatalytic and 'walking bleach' procedures using 30 per cent hydrogen peroxide. In 54.41 per cent of teeth, gutta-percha and AH26 root-fillings were kept at the height of the cemento-enamel j unction while 18.63 per cent were below and 26.96 per cent were above the CEJ. Sealing cement was not placed over the gutta-percha and AH26 root-fillings in any of the teeth in the study. It was found that a to tal of four teeth from the sample group (1.96 per cent) had developed invasive cervical resorption during the review period. All of these te eth had a history of traumatic injury and the level of gutta-percha wa s at the CEJ. The incidence of resorption found in this study of root- filled teeth using a combined thermocatalytic and 'walking bleach' tec hnique is lower than previously reported and indicates a relatively lo w risk of invasive cervical resorption using the technique outlined.