title: Evaluation for cracks associated with ultrasonic root-end preparation of gutta-percha filled canals.
abstract: Many clinicians use ultrasonics for root-end preparations. The purpose of this study was to evaluate resected root-end surfaces of bilaterally matched human teeth for cracks before and after ultrasonic root-end preparation. Twenty matched pairs of extracted single rooted teeth were divided into two experimental groups. In group 1, root-end resection was performed on uninstrumented teeth. In group 2, root-end resection was performed after the canals were instrumented and filled with gutta-percha. All teeth in both groups received root-end preparations using ultrasonic instrumentation at low power. Two examiners evaluated the root-ends after root-end resection and again after root-end preparation using zoom magnification of 20x to 63x. The number, types, and location of cracks were mapped. There were no significant differences when gutta-percha filled roots were compared to uninstrumented roots with regard to the number or type of cracks after root-end resection or root-end preparation. In addition, there were no significant differences in the number or type of cracks following root resection and ultrasonic root-end preparation when compared to teeth with root resection alone.
authors.affiliation: Oregon Health Sciences University, Portland, USA.
authors.forename: K L
authors.initials: KL
authors.lastname: Beling
authors.forename: J G
authors.initials: JG
authors.lastname: Marshall
authors.forename: L A
authors.initials: LA
authors.lastname: Morgan
authors.forename: J C
authors.initials: JC
authors.lastname: Baumgartner
mesh_terms: D000704:Analysis of Variance; D003786:Dental Pulp Cavity / Q000293:injuries*; D003804:Dentin / Q000293:injuries; D005069:Evaluation Studies as Topic; D006171:Gutta-Percha; D006801:Humans; D012184:Retrograde Obturation; D018915:Root Canal Preparation / Q000009:adverse effects / Q000379:methods*; D019227:Tooth Apex / Q000293:injuries / Q000601:surgery; D014082:Tooth Fractures / Q000209:etiology; D014092:Tooth Root / Q000293:injuries*; D014464:Ultrasonic Therapy / Q000009:adverse effects*
chemical_list: D006171:Gutta-Percha