0099-2399/91/1709-0469/$03.00/0 JOURNAL OF ENDODONTICS Copyright 9 1991 by The American Association of Endodontists
Printed in U.S.A.
VOL. 17, NO. 9, SEPTEMBER1991
Two Root Canals in a Maxillary Central Incisor with Enamel Hypoplasia Saad AI-Nazhan, BDS, MSD
The central incisor was tender to percussion and palpation. Electric pulp tester and thermal tests elicited no response from the tooth. Radiographical examination showed one root and two clear root canals with no periapical changes (Fig. 1). A necrotic pulp with acute apical periodontitis was diagnosed. After rubber dam isolation, the tooth and operating field were disinfected with 30% hydrogen peroxide, followed by 5% tincture of iodine. The tooth and operating field were redisinfected after the access opening was established. Two
Presented is a case of enamel hypoplasia of a maxillary central incisor which was referred for endodontic therapy. Radiographical examination revealed a tooth having one root and two canals. Endodontic therapy was performed under aseptic conditions.
The morphology of the teeth is discussed widely in the literature. The presence of an additional canal in the maxillary central incisor is extremely rare, as is indicated in several published anatomical studies (1-5). The presence of an additional canal in the maxillary central incisor has been mentioned in the literature in case reports (6-10). This anatomical variation is thought to be limited to teeth with developmental anomalies such as gemination and fusion. The presence of such an anomaly will result in obscure morphological configurations of the root canal. Enamel hypoplasia is considered to be one of the developmental anomalies affecting only the enamel structure, It refers to hypomaturation of the enamel. This case report discusses endodontic therapy of a maxillary central incisor with enamel hypoplasia and two canals in one root.
CASE R E P O R T A 15-yr-old female was referred to the Endodontic Department at King Saud University, College of Dentistry, from the emergency clinic for further examination of the maxillary right central incisor. Clinical examination revealed a noncarious clinical crown with a well-defined horizontal line separating the tooth crown into two halves. The cervical half of the crown was covered by enamel, whereas the incisal half was discolored and covered by dentin. Maxillary and mandibular centrals, canines, and first molars were affected, and the condition was diagnosed as enamel hypoplasia. Medical history was noncontributory. However, the mother gave a history of rubella and scarlet fever during pregnancy. The mother also claimed that she was severely sick during that period. She mentioned that the patient was always sick during the first 2 yr of life.
FIG 1. Preoperative radiograph showing two canals.
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Journal of Endodontics
FIG 2, Working length determination of the two canals,
FIG 3. Obturation of the canals.
separate access openings were made, and two canals were located. The working length of both canals was checked radiographically (Fig. 2). The canals were instrumented, irrigated with 1% sodium hypochlorite, and dried with sterile paper points. A 2% iodine-potassium iodide was placed into the pulp space between the visits. At the obturation visit, the tooth was asymptomatic. The canals were irrigated with sodium hypochlorite and dried with sterile paper points. Obturation was done by using lateral condensation of gutta-percha and AH26 sealer cement. Access opening was sealed with composite restoration, rubber dam was removed, and postoperative radiograph was taken (Fig. 3).
Enamel hypoplasia is a defect that occurs as a result of any disturbance in the formation of the enamel matrix. The cause is usually of local, systemic, or hereditary origin ( 13, 14). The dentin, cementum, and pulp are normal, and the incidence of caries is low (15). Exanthematous diseases such as scarlet fever may cause enamel hypoplasia, affecting teeth that form within the first year after birth or those that form somewhat later (16). As mentioned earlier concerning the case presented here, the mother had been sick during pregnancy and the child was ill during childhood. This might explain the enamel hypoplasia in this case (13, 14, 16). Slowey (17) pointed out the importance of radiographical examination in detecting an extracanal. Although the maxillary central incisor usually has one canal, the clinician must prepare himself for unexpected root canal morphology when performing root canal therapy.
DISCUSSION Many reports of anatomical studies stated that maxillary central incisors have a single root and one canal 100% of the time (1-5). The only variation is the presence of lateral canals (2, 11, 12). None of the anatomical studies mentions the presence of developmental anomalies. When anomalies are present in a tooth, they may affect the form, size, and structure of the tooth. Case reports of the maxillary central incisor with developmental anomaly are reported in the literature as gemination (9, lO).
Dr. AI-Nazhan is affiliated with the Department of Resotrative Dentistry, Division of Endodontics, University of King Saud, College of Dentistry, Riyadh, Saudia Arabia. Address requests for reprints to Dr. Saad AI-Nazhan, RDS Department, Division of Endodontics, College of Dentistry, University of King Saud, P.O. Box 60169, Liyadh, Saudi Arabia 11545. References 1. Green D. A stereomicroscopic study of the root apices of 400 maxillary and mandibular teeth. Oral Surg 1956;9:1224-32. 2. Pineda F, Kutter Y. Mesiodistal and buccolingual roentgenographic investigation of 7,275 root canals. Oral Surg 1972;33:101-10. 3. Ingle J, Beveridge E. Endodontics. 2nd ed. Philadelphia: Lea & Febiger, 1976:117.
Vol. 17, No. 9, September 1991 4. Vertucci F. Root canal anatomy of the human permanent teeth. Oral Surg 1984;58:589-99. 5. Weine F. Endodontic therapy. 4th ed. St. Louis: CV Mosby, 1989:220. 6. Todd H. Maxillary right central incisor with two root canals. J Endodon 1976;2:227. 7. Mader C, Konzelman J. Double-rooted maxillary central incisor. Oral Surg 1980;50:99. 8. Sinai I, Lustbader S. A dual-rooted maxillary central incisor. J Endodon 1984;10:105-6. 9. Libfeld H, Stabholz A, Friedman S. Endodontic therapy of bilaterally geminated permanent maxillary central incisors. J Endodon 1986;12:214-6. 10. Hosomi T, Masataka Y, Yaoi M, Sakiyama Y. A maxillary central incisor having two root canals geminated with a supernumerary tooth. J Endodon 1989;15:161-3.
Maxillary Central Incisor with Two Canals
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11. Altman M, Guttuso J, Seidberg B, Langeland K. Apical root canal anatomy of human maxillary central incisors. Oral Surg 1970;30:694-8. 12. Kasahara E, Yasuda E, Yamamoto A, Anzai M Root canal system of the maxillary central incisor. J Endodon 1990;16:158-61. 13. Shklar G, McCarthy P. The oral manifestations of systemic disease. 1st ed. Woburn, MA: Butterworth Inc., 1976:17-22. 14. Pindborg J. Aetiology of developmental enamel defects not related to fluorosis. Int Dent J 1982;32:123-34. 15. Toiler P. A clinical report on sex cases of amelogenesis imperfecta. Oral Surg 1967;12:325-33. 16. Shafer W, Hine M, Levy B. A textbook of oral pathology. 3rd ed. Philadelphia: WB Saunders, 1974:48-54. 17. Slowey R. Radiographic aids in the detection of extra root canals. Oral Surg 1974;37:762-72.
T h e W a y It W a s Further notes on the changing prevalence of diseases. In 1930 there were nine times as many deaths from stomach cancer as from lung cancer. That ratio is now reversed. Why does this remind me of another piece of data that shows cigarettes to have the highest profit margin of all widely distributed consumer products? Zachariah Yeomans
Printed in U.S.A.
VOL. 17, NO. 9, SEPTEMBER1991
Two Root Canals in a Maxillary Central Incisor with Enamel Hypoplasia Saad AI-Nazhan, BDS, MSD
The central incisor was tender to percussion and palpation. Electric pulp tester and thermal tests elicited no response from the tooth. Radiographical examination showed one root and two clear root canals with no periapical changes (Fig. 1). A necrotic pulp with acute apical periodontitis was diagnosed. After rubber dam isolation, the tooth and operating field were disinfected with 30% hydrogen peroxide, followed by 5% tincture of iodine. The tooth and operating field were redisinfected after the access opening was established. Two
Presented is a case of enamel hypoplasia of a maxillary central incisor which was referred for endodontic therapy. Radiographical examination revealed a tooth having one root and two canals. Endodontic therapy was performed under aseptic conditions.
The morphology of the teeth is discussed widely in the literature. The presence of an additional canal in the maxillary central incisor is extremely rare, as is indicated in several published anatomical studies (1-5). The presence of an additional canal in the maxillary central incisor has been mentioned in the literature in case reports (6-10). This anatomical variation is thought to be limited to teeth with developmental anomalies such as gemination and fusion. The presence of such an anomaly will result in obscure morphological configurations of the root canal. Enamel hypoplasia is considered to be one of the developmental anomalies affecting only the enamel structure, It refers to hypomaturation of the enamel. This case report discusses endodontic therapy of a maxillary central incisor with enamel hypoplasia and two canals in one root.
CASE R E P O R T A 15-yr-old female was referred to the Endodontic Department at King Saud University, College of Dentistry, from the emergency clinic for further examination of the maxillary right central incisor. Clinical examination revealed a noncarious clinical crown with a well-defined horizontal line separating the tooth crown into two halves. The cervical half of the crown was covered by enamel, whereas the incisal half was discolored and covered by dentin. Maxillary and mandibular centrals, canines, and first molars were affected, and the condition was diagnosed as enamel hypoplasia. Medical history was noncontributory. However, the mother gave a history of rubella and scarlet fever during pregnancy. The mother also claimed that she was severely sick during that period. She mentioned that the patient was always sick during the first 2 yr of life.
FIG 1. Preoperative radiograph showing two canals.
469
470
AI-Nazhan
Journal of Endodontics
FIG 2, Working length determination of the two canals,
FIG 3. Obturation of the canals.
separate access openings were made, and two canals were located. The working length of both canals was checked radiographically (Fig. 2). The canals were instrumented, irrigated with 1% sodium hypochlorite, and dried with sterile paper points. A 2% iodine-potassium iodide was placed into the pulp space between the visits. At the obturation visit, the tooth was asymptomatic. The canals were irrigated with sodium hypochlorite and dried with sterile paper points. Obturation was done by using lateral condensation of gutta-percha and AH26 sealer cement. Access opening was sealed with composite restoration, rubber dam was removed, and postoperative radiograph was taken (Fig. 3).
Enamel hypoplasia is a defect that occurs as a result of any disturbance in the formation of the enamel matrix. The cause is usually of local, systemic, or hereditary origin ( 13, 14). The dentin, cementum, and pulp are normal, and the incidence of caries is low (15). Exanthematous diseases such as scarlet fever may cause enamel hypoplasia, affecting teeth that form within the first year after birth or those that form somewhat later (16). As mentioned earlier concerning the case presented here, the mother had been sick during pregnancy and the child was ill during childhood. This might explain the enamel hypoplasia in this case (13, 14, 16). Slowey (17) pointed out the importance of radiographical examination in detecting an extracanal. Although the maxillary central incisor usually has one canal, the clinician must prepare himself for unexpected root canal morphology when performing root canal therapy.
DISCUSSION Many reports of anatomical studies stated that maxillary central incisors have a single root and one canal 100% of the time (1-5). The only variation is the presence of lateral canals (2, 11, 12). None of the anatomical studies mentions the presence of developmental anomalies. When anomalies are present in a tooth, they may affect the form, size, and structure of the tooth. Case reports of the maxillary central incisor with developmental anomaly are reported in the literature as gemination (9, lO).
Dr. AI-Nazhan is affiliated with the Department of Resotrative Dentistry, Division of Endodontics, University of King Saud, College of Dentistry, Riyadh, Saudia Arabia. Address requests for reprints to Dr. Saad AI-Nazhan, RDS Department, Division of Endodontics, College of Dentistry, University of King Saud, P.O. Box 60169, Liyadh, Saudi Arabia 11545. References 1. Green D. A stereomicroscopic study of the root apices of 400 maxillary and mandibular teeth. Oral Surg 1956;9:1224-32. 2. Pineda F, Kutter Y. Mesiodistal and buccolingual roentgenographic investigation of 7,275 root canals. Oral Surg 1972;33:101-10. 3. Ingle J, Beveridge E. Endodontics. 2nd ed. Philadelphia: Lea & Febiger, 1976:117.
Vol. 17, No. 9, September 1991 4. Vertucci F. Root canal anatomy of the human permanent teeth. Oral Surg 1984;58:589-99. 5. Weine F. Endodontic therapy. 4th ed. St. Louis: CV Mosby, 1989:220. 6. Todd H. Maxillary right central incisor with two root canals. J Endodon 1976;2:227. 7. Mader C, Konzelman J. Double-rooted maxillary central incisor. Oral Surg 1980;50:99. 8. Sinai I, Lustbader S. A dual-rooted maxillary central incisor. J Endodon 1984;10:105-6. 9. Libfeld H, Stabholz A, Friedman S. Endodontic therapy of bilaterally geminated permanent maxillary central incisors. J Endodon 1986;12:214-6. 10. Hosomi T, Masataka Y, Yaoi M, Sakiyama Y. A maxillary central incisor having two root canals geminated with a supernumerary tooth. J Endodon 1989;15:161-3.
Maxillary Central Incisor with Two Canals
471
11. Altman M, Guttuso J, Seidberg B, Langeland K. Apical root canal anatomy of human maxillary central incisors. Oral Surg 1970;30:694-8. 12. Kasahara E, Yasuda E, Yamamoto A, Anzai M Root canal system of the maxillary central incisor. J Endodon 1990;16:158-61. 13. Shklar G, McCarthy P. The oral manifestations of systemic disease. 1st ed. Woburn, MA: Butterworth Inc., 1976:17-22. 14. Pindborg J. Aetiology of developmental enamel defects not related to fluorosis. Int Dent J 1982;32:123-34. 15. Toiler P. A clinical report on sex cases of amelogenesis imperfecta. Oral Surg 1967;12:325-33. 16. Shafer W, Hine M, Levy B. A textbook of oral pathology. 3rd ed. Philadelphia: WB Saunders, 1974:48-54. 17. Slowey R. Radiographic aids in the detection of extra root canals. Oral Surg 1974;37:762-72.
T h e W a y It W a s Further notes on the changing prevalence of diseases. In 1930 there were nine times as many deaths from stomach cancer as from lung cancer. That ratio is now reversed. Why does this remind me of another piece of data that shows cigarettes to have the highest profit margin of all widely distributed consumer products? Zachariah Yeomans
