title: A spectrophotometric analysis of dentinal leakage in the resected root.
abstract: The purpose of this study was to compare dye leakage in the dentin of resected and nonresected roots. Fifty-four single rooted extracted teeth were used. The two groups were subdivided into young, middle age, and old age samples. Each sample was biomechanically prepared in a standard fashion and obturated using lateral condensation with sealer and gutta-percha. All root surfaces were sealed with nail polish, leaving the apical portion exposed. The apical portion of the roots were placed in 2% methylene blue dye for 72 h, rinsed, and placed in 15 ml of 35% HNO3 for 72 h. The supernatant was analyzed at 640 nm using a visible light spectrophotometer. The amount of leakage was extrapolated from a standard linear regression curve constructed from the stock 2% methylene blue dye solution. The percentage of concentration leakage in all samples ranged from less than 0.0600 to 0.1658. It was concluded that there is a greater amount of leakage in resected versus nonresected extracted teeth. The data also suggest that older teeth exhibit less leakage than younger teeth.
authors.affiliation: Department of Endodontics, University of Michigan School of Dentistry, Ann Arbor.
authors.forename: W R
authors.initials: WR
authors.lastname: Ichesco
authors.forename: R L
authors.initials: RL
authors.lastname: Ellison
authors.forename: J F
authors.initials: JF
authors.lastname: Corcoran
authors.forename: D C
authors.initials: DC
authors.lastname: Krause
mesh_terms: D000328:Adult; D000367:Age Factors; D000704:Analysis of Variance; D003763:Dental Leakage / Q000175:diagnosis* / Q000503:physiopathology; D006171:Gutta-Percha; D006801:Humans; D008751:Methylene Blue; D008875:Middle Aged; D012044:Regression Analysis; D012389:Root Canal Obturation; D012390:Root Canal Therapy; D013053:Spectrophotometry; D014092:Tooth Root / Q000601:surgery*
chemical_list: D006171:Gutta-Percha; D008751:Methylene Blue