title: A comparison of the apical dye penetration patterns shown by methylene blue and india ink in root-filled teeth.
abstract: This study compared the linear leakage patterns shown by 5% aqueous solution of methylene blue (MB) and India ink (II). One-hundred and twenty-five roots with single canals from extracted human teeth were used. The canals were cleaned and shaped using the step-back technique under copious irrigation. Three groups were arranged to receive root fillings of gutta-percha and one of three proprietary sealers using standard lateral condensation techniques: Sealapex (40 roots), Tubli-Seal (40 roots) and Ketac-Endo (20 roots). The remaining roots were used as controls: positive with gutta-percha and no sealer and negative with the apices sealed with nail varnish. The roots were randomly selected for 7-day immersion in either MB or II, then sectioned longitudinally; dye penetration was assessed using a Wild Leitz stereomicroscope. In all groups MB showed more penetration than II. The results were statistically significant at the P = 0.01 level, with the exception of the positive control groups. Negative controls showed no penetration. It is concluded that MB, which has a low molecular weight penetrated more deeply along root canal fillings than II, which has a large particle size.
authors.affiliation: Department of Conservative Dentistry, The London Medical College Dental Institute, London, United Kingdom.
authors.forename: K M
authors.initials: KM
authors.lastname: Ahlberg
authors.forename: P
authors.initials: P
authors.lastname: Assavanop
authors.forename: W M
authors.initials: WM
authors.lastname: Tay
mesh_terms: D002126:Calcium Hydroxide; D002244:Carbon; D004396:Coloring Agents; D003763:Dental Leakage / Q000175:diagnosis*; D005069:Evaluation Studies as Topic; D005899:Glass Ionomer Cements; D006171:Gutta-Percha; D006801:Humans; D008422:Materials Testing / Q000379:methods; D008751:Methylene Blue; D012387:Root Canal Filling Materials; D012389:Root Canal Obturation; D012459:Salicylates; D018709:Statistics, Nonparametric; D015035:Zinc Oxide-Eugenol Cement
chemical_list: D004396:Coloring Agents; D005899:Glass Ionomer Cements; C074934:Ketac Endo; D012387:Root Canal Filling Materials; D012459:Salicylates; D015035:Zinc Oxide-Eugenol Cement; C028433:chinese ink; C055601:Sealapex; C048769:tubliseal; D002244:Carbon; D006171:Gutta-Percha; D002126:Calcium Hydroxide; D008751:Methylene Blue