ENDODONTIC FAILURES DUE TO VERTICAL ROOT FRACTURES: TWO CASE REPORTS John J. Plant, DDS, and Robert A. Uchin, I)DS, Miami
Unexpected and perplexing failures of endodontically treated teeth are frequently caused by vertical root fractures. The following case reports illustrate typical endodontic failures caused by vertical root frac.tures in maxillary and mandibular premolars.
Report of Cases 9 Case 1. The patient had a routine recall examination of the mandibular left first premolar that had been treated endodontically 29 a~onths previously. The tooth exhibited Class II mobility. A buccal periodontal pocket could be probed to the apex of the root. R a d i o g r a p h i c e x a m i n a t i o n showed a radicular radiolucent area that encompassed a substan,tial portion of the root (Fig 1). The tooth originally ,had been endodontically treated because of a carious pulp exposure (Fig 2, 3). An intraradicular post and a cast crown were placed to restore the tooth after completion of the endodontic treatment. Results of a recall examination at 12 months were within normal limits clinically ,and radiographically (Fig 4). Six months after the one-year examination, the patient reported a loss of the post and crown. A new restoration was made similar to the original. The dentist who performed ,the restoration at this point suspected a possible root fracture, but careful clinical examination did not confirm the suspected diagnosis. No radiographic record of this episode was made.
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Fig 1--Mandibular left first premolar 30 months after endodontic treatment; second post and crown restoration was in p l a c e / o r 11 months. Buccal periodontal pocket could be probed to apex.
Fig 2 - - B e / o r e endodontic treatment.
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Fig 4--Twelve months after endodontic treatment, with first post and crown restoration in place.
Fig 3--Completed endodontic filling.
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Fig 5--Clinical appearance of surgically exposed fractured root.
Fig 6--Extracted tooth demonstrates vertical fracture of entire root. 54
JOURNAL OF ENDODONTICS I VOL 2, NO 2, FEBRUARY 1976
Eleven months af.ter the second post and crown were placed, or 29 months after the original endodontic treatment, the patient had a recall examin,ation with the conditions as described previously (Fig 1). Subsequently, a buccogingival flap was reflected to confirm vertical fracture of the buccal surface of the root (Fig 5). The tooth was extracted (Fig 6).
Fig 7--Maxillary le/t second premolar at time o/consultation.
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Fig 8--Clinical appearance of surgically exposed fractured root.
9 Case 2. The patient reported for endodontic consultation with the following history: The maxi.llary leYt second premolar had originally been treated by nonsurgical endodontic procedures that included a filling of gutta-percha 9 Persistent discomfort after this treatment had prompted the dentist to perform an apicoectomy. The tooth remained sore after the surgery and was tender at the time of consultation. Radiographic examination showed uniform widening of the entire periodontal ligament as well as a radiolucent periapical area (Fig 7). Vertical root fracture was suspected and a negative prognosis was conveyed to the patient, who agreed to diagnostic surgical exploration of the root. Reflection of a full mucoperiosteal flap confirmed the root fracture (Fig 8). The tooth was extracted. Discussion
Endodontic access openings weaken teeth by destroying the strong arch configuration of dentin over the pulp chamber. Therefore, we think that the smallest access that permits unobstructed, direct approach to all root canals is indicated. Root canals should be enlarged to the minimum size that permits complete debridement and shaping. This should provide adequate
access for thorough condensation of filling materials. It is undesirable to enlarge any root canal to an arbi'trarily large size, losing strength of tooth structure in the process. Gross heavy pressure is unjustified when filling materials are vertically or laterally condensed into root canals. If extreme vertical pressure is required to force filling materials (silver or gutta-percha) to proper position, then either the canal is inadequately prepared or the master cone is improperly fitted. Extreme lateral pressure is also to be avoided during la,teral condensation procedures. When intraradicular posts are indicated, they should be designed and inserted with the dangers of root fracture in mind. Retention is better gained by post length than by post diameter 9 Posts should be vented to avoid excessive hydraulic pressure during cementation. The cementing medium should be as smooth as possible for the same reason. Summary Vertical fracture of endodontically treated roots is more lhan a rare occurrence. Two typical cases have been reported. Awareness of this potential problem during endodontic treatment and restoration of endodontically treated teeth may help to avoid this disappointing situation. Dr. Plant is a staff endodontist, and Dr. Uchin is director, endodontic residency program, Veterans Administration Hospital, Miami. Requests for reprints should be directed to Dr. J. J. Plant, Veterans Administration Hospital, 1202 NW 16th St, Miami, Fla 33125.
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