0099-2399/85/1107-0301/$02.00/0 JOURNALOF ENDODONTICS Copyright 9 1985 by The American Association of Endodontists
Printed in U.S.A. VOL. 11, NO. 7, JULY1985
CASE REPORTS Foreign Object Removal Utilizing the Cavi-Endo Ultrasonic Instrument Remocion de Objetos Extranos Utilizando el Instrumento Ultrasonico Cavi-Endo Dennis L. Meidinger, DDS, and Barbara J. Kabes, DDS
Removal of foreign objects from root canals is often a very difficult procedure. Two cases are presented in which the Cavi-Endo ultrasonic instrument was utilized to remove a fractured dental bur tip and amalgam particles.
scaler may aid in removal of solid objects from the radicular pulp space. These objects include silver points, preformed metal posts, customized cast post/ core restorations, and separated or intentionally cemented hand instruments. Cohen and Burns (7) have stated that the ultrasonic wave can be used to break
La remocion de objetos extra~os del conducto radicular es a menudo muy dificultosa. Se presentan dos casos en los que se utiliz6 el instrumento ultrasonico Cavi-Endo para remover el extremo de una fresa dental fracturada y particulas de amalgama.
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Ultrasonic instruments are a welcomed addition to the armamentarium to aid in the removal of foreign objects from root canals. The literature is sparse on the subject of foreign object removal. Fors and Berg (1) described a technique that required removal of internal root structure. RoigGreene (2) demonstrated a simple divice using a disposable 25-gauge dental needle, a segment of thin steel wire, and a small mosquito hemostat to remove objects such as silver cones from root canals. Williams and Bjorndal (3) used the Masserann technique to remove fractured posts. Taintor et al. (4) described seven methods of silver cone removal but ultrasonic methods were absent. Ultrasonic instruments have been used in dentistry the past three decades. The primary application in dentistry has been for external cleaning of teeth. Recently, Cunningham and Martin (5) have advocated the use of ultrasonics in canal debridement and instrumentation. Ultrasonic instruments may also be useful for removing foreign objects from root canals. Gaffney et al. (6) stated that the use of the ultrasonic
FIG 1. Radiographic evidence of the separated bur tip in the apical portion of tooth # 8 . 301
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and loosen cementing bonds of preformed dowels, cast posts, or silver cones from canals without damaging root structure. Krell et al. (8) demonstrated techniques to remove silver cones that are separated at the pulpal floor or farther apically in the canal. Their initial method employed a Hedstrom file to engage the silver cone. An ultrasonic scaler was brought in contact with the file and activated. The silver cones could be removed when the Hedstrom file was withdrawn after ultrasonic scaler activation. A second method involved the Masserann technique to reach silver cones which are separated farther apically in the canal. The authors demonstrated that after the silver cone has been engaged, the ultrasonic scaler was again successful in removing the object. CASE REPORTS Case 1
A 26-yr-old oriental male presented at the University of Nebraska College of Dentistry for treatment of tooth #8. Diagnostic tests indicated endodontic therapy was necessary for treatment of this tooth. During access preparation, the head of a #170-L bur
separated in the canal. The broken bur was pushed apically when the student attempted to determine the working length. When a working length film was taken, the foreign object was discovered and identified. The separated portion of the bur blocked the apical portion of the canal (Fig. 1). A # 1 0 K file was negotiated past the broken bur tip and the canal instrumented until a # 1 5 file would pass the bur. A # 1 5 file was placed in a Cavi-Endo (Dentsply/ Cavitron Dental Unit, Dentsply International Inc., York, PA) ultrasonic unit and worked past the object. The instrument was activated, and the canal enlarged using 2.5% NaOCI as an irrigant. The procedure was repeated until a # 2 5 file went to place. Attempts to engage the bur tip with a Hedstrom file failed. A #25 file in the Cavi-Endo instrument was reintroduced into the canal with 2.5% NaOCI as an irrigant. This time the object was immediately dislodged and came floating out with the irrigant (figs. 2 and 3). Conventional endodontic therapy was then completed (Fig. 4). Case 2
A 30-yr-old white female presented to the University of Nebraska Medical Center, College of Dentistry, for
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FIG 2: Radiographic evidence of the bur tip removed.
F~G3. Photograph of the bur tip removed by the Cavi-Endo ultrasonic unit.
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FiG 6. Radiographic evidence of amalgam particles in the distal root.
FiG 4. Postoperative radiograph demonstrating gutta-percha obturation. Note the slight overextension.
FIG 7. Removal of amalgam particles has been achieved with the Cavi-Endo ultrasonic unit.
FIG 5. Preoperative radiograph of tooth #19 prior to retreatment.
retreatment of the endodontic therapy on her mandibular left first molar (Fig. 5). After the initial visit and before her obturation appointment, the patient noted a strong medicinal taste. Upon examination it was noted that the temporary restoration was intact and that the distal amalgam restoration was loose. The remaining amalgam restoration was removed, following cleansing of the canals, a cotton pellet with camphorated monochlorophenol was sealed into the pulp chamber and gutta-percha temporary stopping was placed over the chamber. A new mesial-occlusal-distal amalgam restoration was then placed and the access again prepared. On the following appointment it was noted that amal-
gam particles were present in the apical third of the distal canal (Fig. 6). After a #15 K file was utilized to reestablish the working length, a #15 file was placed into a Cavi-Endo ultrasonic unit, and with a 2.5% NaOCI irrigant the amalgam particles were removed from the canal (Fig. 7). DISCUSSION The Cavi-Endo instrument was successful in both of these cases in the removal of a broken bur tip and amalgam particles from the intracanal space. Ultrasonic instruments are a welcome addition to the endodontic armamentarium for foreign object removal. These instruments often prove successful and do not require the gross removal of root structure as in other techniques advocated for removing objects and material from the root canal systems.
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We wish to express our thanks and appreciation to Dr. William T. Johnson and Andrea Schwartz for their assistance in preparation of the manuscript. Dr. Meidinger is a senior endodontic resident, Dental College, University of Nebraska, Lincoln, NE. Dr. Kabes is a first-year endodontic resident, Dental College, University of Nebraska.
References 1. Fors UGH, Berg JO. A method for the removal of broken endodontic instruments from root canals. J Endodon 1983;9:156-9. 2. Roig-Greene JL. The retrieval of foreign objects from root canals: a
Journal of Endodontics simple aid. J Endodon 1983;9:394-3. 3. Williams VD, Bjorndal AM. The Masserann technique for the removal of fractured posts in endodontically treated teeth. J Prosthet Dent 1983;49:46-8. 4. Taintor JF, Ingle JI, Fahid A. Retreatment versus further treatment. Clin Prevent Dent 1983;5:8-14. 5. Cunningham WT, Martin H. A scanning electron microscope evaluation of root canal debridement with the endosonic ultrasonic synergistic system. Oral Surg 1982;53:527-31. 6. Gaffney JL, Lehman JW, Miles MJ. Expanded use of the ultrasonic scaler. J Endodon 1981 ;7:228-9. 7. Cohen S, Burns RC (eds). Pathways of the pulp. 3rd ed. St. Louis: CV Mosby Co., 1984:294. 8. Krell KV, Fuller MW, Scott GL. The conservative retrieval of silver cones in difficult cases. J Endodon 1984;10:269-73.