Klinghofer, Anne2023-03-242023-03-2419901990https://hdl.handle.net/2144/45803Thesis (M.Sc.D.)--Boston University, Henry M. Goldman School of Graduate Dentistry. Dept. of Endodontics, 1990.Includes bibliography: leaves 115-125.The objectives of this study were to compare in vivo the ability of the irrigation during the cleaning and shaping (B.U. Technique) of teeth with necrotic pulps that radiographically exhibit the presence or absence of lesions of endodontic origin. The evaluation of the irrigant's penetration was evaluated as a function of the initial and final shape of the canals, size and type and motion of the instruments used (K Files, Reamer s), type of irrigation delivered (Static or Dynamic). Hypaque was used as the irrigating solution because of its similar physical properties to Sodium Hypochlorite and its radiopaque properties. Radiographs were taken at each step of the treatment to visualize the efficiency of the irrigant's penetration. A comparison of the irrigation's efficiency during the cleaning and shaping procedure of necrotic pulp teeth with or without lesions of endodontic origin was also studied. The results showed that there were no major differences between the two groups. The use of small files (#10 Files, #15 Files) in narrow canals brings the irrigant very effectively to the apical third at the beginning of the procedure: this is called "the dynamics of irrigation". The use of reamers in Schilder's envelope of motion to shape the body of the canal greatly improves the efficiency of the irrigant's depth penetration in the apical third. In more than 90% of the cases, the solution reaches the radiographic terminus even after the use of a #20 File, and to 100% after the use of a #25 File. The in vivo use of a radiopaque irrigant during this technique clearly showed the presence of bifidities, lateral and accessory canals within the root canal system. No Hypaque was detected beyond the radiographic terminus even when a file #120 was used as last instrument. The results demonstrated the ability of the hand instrumentation technique to be in complete harmony with the irrigation of the entire root canal system.en-USThis work is being made available in OpenBU by permission of its author, and is available for research purposes only. All rights are reserved to the author.Root Canal PreparationThesis/Dissertation