Vertical root fracture: A case report Elaine Vianna Freitas Fachin*

A case report involving vertical root fracture in an endodontically treated mandibular left first molar is presented. Pain and extensive tissue damage occurred in the area 2 years after root canal therapy. The periapical radiograph .-iuggested endodontic failure, and re-treatment was initially considered. However, the problem was related to a com- plete vertical root fracture in the distal root, which was only visible after removal of the gold crown. The tooth was extracted because severe periodontal destruction had been caused by the root fracture. (Quintessence Int 1993:24:497-500.)

Introduction Food Stains and baeterial breakdown products may stain the eraek. suggesting possible fracture lines. Diagnosis of vertical root fractures in endodontically However, this is not a reliable diagnostic guide and treated teeth presents many problems. These are fur- is only significant in the presence of tissue reeession, ther complicated by the appearance of late signs and when the root can be visualized. Diagnostic tests that symptoms that imitate endodontic failure or peri- can be used as adjuncts in evaluation include use of odontal lesions.'"* The fracture is usually not visible méthylène blue dye for root and coronal fractures,' radio graphie ally, espeeially early in its development, biting and pressure techniques for separating frac- atitl can be further obscured by other dental and an- tured segments,"^ and transillumination. Nonetheless, atomic structures or the obturated canal itself. it is hard to detect a fracture on molars, because pos- Clinically, the patient exhibits pain on percussion terior teeth are often restored with metal erowns that and discomfort associated with a marked destruction obscure possible fracture hnes." of supporting structures.^'' Some patients have pain The purpose of this paper is to report a case of on mastication, and they often are not able to identify vertical root fracture and address its possible causes. whether it conies from the maxillary or mandibular arch. Early attempts at diagnosis with periodontal probes is of questionable value, because they do not Case report clearly demonstrate the crack. A 70-year-old black man, presented to the Postgrad- Ingle and Taintor' reported that fractured roots uate Endodontic Clinic of the university of Illinois at have bizarre symptoms and thai diagnosis is direetly Chicago with pain on percussion in the mandibular related to the extent of the fraeture. Stanley* described left first molar. Two years earlier, root canal therapy the symptoms as progressively developing to the point had been completed and the looth was restored with of excruciating pain. a full-gold crown. The radiograph revealed that ex- tensive bone loss was associated with the distal root (Fig 1), compared to that shown on a radiograph taken 2 years earlier, at the end of the endodontic therapy (Fig 2). Periodontal probing on the distolin- gual surface revealed a deep pocket (8 to 9 mm), and, clinically, the mandibular left first molar was mobile. The patient's past dental history did not indicate any Professor of Endodontics, Federal University of Rio Grande do previous periodontal involvement in this or any other Sul, College of , Caixa Postal 1118,90 210 Porto Alegre, region of the mouth. Rio Grande do Sul, Brazil.

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Fig 1 Severe periodonlal breakdown of the mandibular Fig 2 Radiograph taken at the completion of endodontic left first molar. treatment of tfie mandibular left first molar, 2 years previ- ously.

Fig 3 (arrows) Buccoiingual fracture iine crossing the dis- tal root.

Fig 4 Extracted mandibuiar first moiar with a complete Fig 5 Dislal root with vertical fracture involving the rool verticai fracture in the distai root. canai.

498 Quintessence Iniernationai Voiume 24, Numtitir 7/1993 Endodoníics

The first treattnent alternative in this case was to the IVaclure is usually cotnplete. extends from one open the tooth through the gold crown and attempt surface to the other, and includes Ihe root canal. re-trcatment, because the pain was thought to be The vertical fracture in this patient may have re- cattsed by endodontie failure. To attain access, the sulted from one or more of the following factors: gold crown was removed, revealing the fracture 1. ¡atrogenic trauma during lateral condensation of through the tloor of the pulp chamber (Fig 3). the gutta-percha during obturation of the ciinal.''-^-'- Ac- Tbe tooth was extracted because of the extensive cording to Meister et al.' 27 of 32 vertical root frac- tissue damage. The fractured fragments exhibited a tures studied were caused by excessive force applied complete crack {Fig 4), extending frotn one surface to during lateral condensation. It has been shown that the other including the root canal (Fig 5). these fractures can occur at spreader loads as small as 7,2 kg," Therefore, the clinician should be careful not to force ftnger spreaders or root canal pluggers beyond that pressure. Occasionally, a clicking sound Discussion can be heard when the endodontie spreader is pushed Vertical root fractures are usually symptom free in into the root canal, producing heavy compression of the early stages and are often tatrogenic. This clinical gutta-percha. The popptng or cracking sound heard problem ts difficult to diagnose because pain and dis- at the lime of obturation is a clinical indication of comfort are either mild or nonexistent, and severe early fracture, in which case the patient must be in- pain is very seldom present. There can be -A persistent formed of the uncertain prognosis, dull pain on mastication as a result of the separation 2, Extensive instrumentation of the root canal of the fractured fragtnents. Later symptoms include space.^" Modern concepts of canal preparation en- periodontal breakdown, soft tissue inflammation, per- courage ñare filmg techniques,'"' aniicurvature filing,'^ iapical radiolucent areas, parietal swellings, suppur- and incremental instrurnentation,"' with the purpose ation, ftstulas. or sinus tracts. Moreover, radiographie of enlarging the canal orifice as weil as cleaning and changes in vertical bone loss are dramatic in the iater shaping the root canal system lo obtain a continu- stages. In addition, a deep periodontal defect is usu- ously tapering funnel from the apical to the coronal ally revealed by probing. area. However, the clinician must be aware tbat large- Most often radiographs fail to disclose the vertical sized Hedström files and extensive use of rotatory fracture because certain angulations produce a diffuse instruments such as Batt burs and Gates-Glidden image, obscuring the fracture hne. Other clinical tests, drills, placed in the cervical area of the root canal, such as transilluniination, the bite test, and the dye weaken the rool structure and may lead to vertical test, are helpful. However, a conclusive diagnosis can fracture. only be made when the affected tooth is explored by 3. Excessive pressure during cementation of the full- surgical means or accessed through the restoration or gold crown as a result of seating or tapping forces. The crown. wedging action of inlays, pins, posts, and crowns are Vertical fractures may occur in vital, nonvital and mentioned in the literature as possible causes of root endodontically treated teeth, in whieh case the poten- fractures,"^ tial irritants found'' in the fracture space and adjacent 4, Accidental biting on a hard object before the com- root canal arc bacteria, nccrotic tissue, food debris, pletion of the complete-crown coverage. Tbis occurs es- and unidentifiable amorpbous substances. However, pecially in endodontically treated teeth, in whieh de- the preeise etioiogic agent that causes the periodontal hydration represents an extra risk for cracks, if" the inflammation has not been determined. It is possible teeth are not restored as soon as the root canal ther- that metabolites from bacterial breakdown, percolat- apy is completed. Endodontically treated teeth are mg fiuids, and disintegration of sealer play important thought to exhibit dehydration of the hard structure roles in tbe etiology. and dentinal tubules, with a rnoisture loss of 9%." The vertical fracture may be complete or incom- Factors such as occlusal trauma caused by a steep plete, including or not including the root canal, ex- cusp and fossa anatomy, attrition, or eccentric contact tending from buccal to lingual or from mesial to dis- on cusp tips, as well as placement of endodontie dow- tal. The characteristics of the case presented were in els, also contribute to fractures.'* accordance with those found by Walton and col- Prognosis of a tooth with a vertical fracture is usu- leagues* in a study of morphologic fracture patterns: ally unfavorable. In single-rooted teeth, extraction is

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5. Linaburg RG, Marshall t-J. The diagnosis and treatmen! of indicated, while in multirooted teeth hemisection and verlical rool fractures, J Am Dent Assoc t973;86:679-683, radiectomy are alternative treatments.'" Often, com- 6 Wallon RE, Michelich RJ, Smilh GN, The histopalhogenesis plete tooth extraction is necessary because of the ex- of verlita! fractures. J Endod 1984;10:48-56. tensive bone loss and the uncertain prognosis for the 7. Ingle Jl, Taintor JF, Endodontics, ed 3. Philadelphia: Lea & remaining tooth structure if hemisection is attempted. Febiger, 1975:779-781, A treatment option other than extraction has been 8. Slanley HR. The . J Am Acad Gold Eoil Oper 19ú8;n:36. suggested by Stewart' in the hopes of saving the frac- 9. Viener AE. Fractured teeth: A cause of odontalgia. Oral Surg tured tooth. In this technique calcium hydroxide plus 1965:20:594, barium sulfate is used to restore the root canal, while 10. Studervant CM, Barton HE, Brauer JC, The An and Science the tooth is rebuilt with a reinforced glass-ionomer of Operative Dentistry, New York: McGraw-Hill, 1968:57. cement, Ketac Silver (ESPE-Premier). The case re- 11. Cameron CE. The cracked tooth syndrome: Additional find- ported in the present paper would not permit any ings. J Am Dent Assoc 1976;93:97l-975. 12. Vertucci FJ. Managenienl of vertical root fracture, J Endod treatment but extraction, because it was a complete 1985,11:126-131, vertical fracture extending from the buccal to the lin- 13. Bender IB, Freedland JB. Adult root fracture. J Am Denl Assoc gual area, producing tooth mobility and extensive de- 1983:107:413^19. struction of the supporting structures. 14. Walton RE. Histologie evaluation of different methods of en- larging the pulp canal spate. J. Endod 1976:2:3t)4-311. 15. Abou Rass M, Frank A, Glick DH. The anticurvature llhng method to prepare the curved root canal, J Am Dent Assoc 1980;101:792-794. References ¡6, Weine FS. Heaiey HJ, Gerstein H, Evanson L, Precurved files and incremental instrumentation for root canal enlargement, 1. Stewart GG. The detection and ttealtnent of vertical root frac- J Can Dent Assoc I97O;36:]55-157. lures. J Endod l98S;l4:47-53. 17. Heifer AR, Meinick S, Schilder H. Determination of the mois- 2. Tamse A, Iatrogenit verticul root fractures in endodonticiilly ture content of vital and pulpless teeth. Oral Surg 1972;34: treated teeth. Endod Dent Traumalül 1988:4:190-195. 661-670, 3. Meisier F, Lommel TG, Gerstein H, Diagnosis and possible IB. Maxwell EH, Braly BV, Eakle S. Incompletely fractured teeth causes of" vertical root fractures. Oral Surg Oral Med Oral Pa- A survey of endodontists. Oral Surg Oral Med Oral Pathol ihol l9!i{);49:243-253. 1986:61:113-117. 4. Pilts DL, Nalkin E, Diagnosis and treatment of vertical root 19. Barkhordar RA. Keniplcr D, Knapp J. Mesiodistal root frac- fractures. J Endod 1983;9;338-34(S. ture. Oral Surg Oral Med Oral Pathol 1988:65:343-348, •

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