The patient had an abnormally shaped maxillary right lateral incisor, termed a double tooth, that was successfully treated by splitting. The classification of the double tooth by origin, to determine correct terminology, is discussed. Treatm ent, however, should be based on the identification of the specific m orphologic abnormality rather than on the classification of its origin.
Comprehensive management of the double tooth: report of case
Allen B. Itkin, DDS
The malformed tooth often is a challenge to the dentist. It is frequently difficult to diagnose the specific developmental disturbance before the formation of a treatment plan to restore function and appearance. The anomalies that may have to be considered are those of the size of the crown, shape of the crown, root form, enamel and dentin formation, pulp and pulp canal morphology, and malposition of the tooth in the arch. The specific developmental defect must be evaluated objec tively to achieve an acceptable result from treat ment. A critical appraisal of the specific anom alies, rather than their classification into termin ology, will dictate the correct management.
Review of the literature The terms gemination, twinning, and fusion have been defined.1'3 Although some confusion still exists, these definitions are generally accepted. —Gemination: the attempt of a single tooth
bud to form two distinct morphologic entities. This may be represented clinically by two iden tical crowns joined in a midline to align in a mirror-image effect.4 Radiographically, the root may be singular with one canal. The tooth may occupy its normal position in the dental arch; however, because of the increased crown size of the tooth, crowding may exist if the adjacent teeth are present. —Twinning: gemination that was complete thus forming two identical adjacent teeth.5 —Fusion: the result of the joining of two ad jacent tooth buds. These can be either two nor mal buds or a normal and supernumerary bud. The clinical appearance would be of nonidentical crowns joined at a midline. Radiographically, two root canals and one or two roots may be evi dent. In many instances it is difficult to differentiate between the fused and geminated tooth.6 9 The term double tooth10 has been suggested to cover both of these possibilities when the true etiology cannot be determined. JADA, Vol. 90, June 1975 ■ 1269
f
:
\
F ig 1 ■ P re o p e ra tiv e clin ica l p h o t o g r a p h s h o w s a b n o r m a l right m a x illa ry
late ra l
incisor
with
o v e rla p pin g
of
central
incisors.
Report of case A 12-year-old girl was referred to us for evalua tion of an abnormally shaped tooth. The patient said that for the past few years she had been con cerned about the appearance of her mouth and teeth when she smiled. The past medical history was noncontributory. There was no history of trauma to the teeth or jaws. Physical examina tion showed a well-developed, well-nourished girl with no other physical abnormalities. Examination of the oral cavity revealed two abnormalities (Fig 1). First, the maxillary right lateral incisor was abnormally shaped. The tooth was unusually wide, measuring 11.5 mm at its greatest width. It was notched in the midline, and this gave it a double-image appearance. Sec ond, the maxillary central incisors were over lapped secondary to the crowding created by the large lateral incisor. Examination of the remain ing oral tissue showed no other abnormalities. Periapical (Fig 2), occlusal, and panoramic radiographs confirmed the previously mentioned dental abnormalities. The maxillary right lateral incisor had the appearance of two identical teeth joined from the apical third of the root to the crown and separating 2 mm cervical to the incisal edge. There were two pulp canals and chambers. The pulp chambers appeared to be connected. On May 9, 1973, the patient was premedicated with 5 mg of diazepam (Valium) intravenously, and local anesthesia was obtained with 2% lidocaine (Xylocaine) hydrochloride with 1:100,000 epinephrine. A mucoperiosteal flap was reflect ed from the gingival margin with lateral extension 1270 ■ JADA, Vol. 90, June 1975
F i g 2 ■ P r e o p e r a tiv e p eria p ica l ra d io g ra p h s h o w s t w o identical te eth a p p a r e n t l y j o in e d at m id lin e .
to the left lateral incisor and right cuspid. The crown of the double tooth was divided with a diamond bur. At this time the communication between pulp chambers was exposed. The roots then were sectioned by following a groove on their labial surface. There was no evidence of pulpal perforation as division of the root pro gressed. After division of the coronal two thirds of the root, the mesial root was removed from its socket. The remaining distal root was treated endodontically (Fig 3). The root and bone sur faces were smoothed with a diamond stone. The wound was irrigated with sterile saline solution
Fig 3
■ P h o t o g r a p h d u r in g s u rg e ry s h o w s s o c k e t w h e r e m esial
h a lf o f t o o t h w a s r e m o v e d
and
pulp
ch a m be r co m m unication.
Fig 5 ■ Radiograph taken in September shows bone deposi tion into mesial defect.
Fig 4 ■ Bony defect is seen in immediate postoperative radio graph.
and the flap closed with no. 4-0 black silk su tures. The patient tolerated the procedure with out difficulty. The immediate postoperative radiograph (Fig 4) showed a periodontal bony defect on the me sial aspect of the remaining tooth. One month postoperatively, it was evident that bone had started to fill the defect at the apical third. Re storative treatment was deferred for three months to permit additional bone deposition. On Sept 6, radiographs showed extensive bone deposition (Fig 5). There was no mobility of the tooth. Preparation for a cast gold post was initiated on Sept 24. At this time a maxillary Hawley appliance was inserted to correct the overlapping central incisors (Fig 6); this was ac complished in two months. The tooth then was prepared for a porcelain-fused-to-gold crown while the patient continued to wear the Hawley appliance without rubber bands to maintain posi tion. On March 22, the permanent crown was cemented (Fig 7).
Discussion The double tooth affords a striking clinical man ifestation of the differentiable and morphogen etic processes of tooth development. It challeng
Fig 6 ■ Hawley appliance in place to close space between lateral and central incisor.
Fig 7 ■ Final clinical photograph taken after completion of orthodontic and restorative treatment.
es us with the problems of defining its origin and restoring it to acceptable function and appear ance. The decision to split and remove a half of the double tooth was made with the thought of a mul tidisciplinary approach to achieve the desired Itkin—Barr: MANAGEMENT OF DOUBLE TOOTH ■ 1271
result. This took into consideration the need for surgical, endodontic, orthodontic, and restora tive treatment. The alternatives to this treatment all had obvious faults. Extraction would neces sitate prosthetic replacement, reshaping and crowning would not achieve the desired esthetic result,11 and no treatment would mean the per petuation the patient’s appearance. In planning the surgery for splitting, these principles should be closely followed. First, re flect full thickness periosteal flaps. Second, only a minimal amount o f labial bone should be re moved. Third, if pulp exposure occurs, complete endodontic treatment should be accomplished. Fourth, stabilization by splinting or wiring may be indicated if excessive mobility o f the remain ing tooth half exists.
Summary A patient with an abnormal maxillary lateral in cisor was treated to restore function and to im prove appearance. Although specific classifica tion o f the problem into accepted terminology was attempted, the term double tooth was used to define the patient’s problem. We have shown that the identification o f the specific abnormal ities, not the etiologic classification, is impor tant to achieve an effective treatment plan.
1272 ■ JADA, Vol. 90, June 1975
We thank Dr. Marlin Troiano, chairman, department of oral surgery, anesthesiology and hospital dental services, for re viewing this paper, and Dr. Harry Tuber, attending, Martland Hospital, and Dr. Richard Salb, general dentistry resident, Mart land Hospital, for their assistance with the restorative and orth odontic management of this patient. Dr. Itkin is clinical professor of oral surgery, anesthesiology, and hospital dental services and director of the division of oral surgery, Martland Hospital, College of Medicine and Dentistry of New Jersey. Dr. Barr is a resident in oral surgery at Martland Hospital, College of Medicine and Dentistry of New Jersey, New Jersey Medical School, 65 Bergen St, Newark, NJ 07107. Ad dress requests for reprints to Dr. Barr. 1. Shafer, W.G.; Hine, M.K.; and Levy, B.M. Textbook o f oral pathology, ed 3. Philadelphia, W. B. Saunders Co., 1974, p 35. 2. Bhaskar, S.N. Synopsis of oral pathology, ed 4. St. Louis, C. V. Mosby Co., 1973, p 29. 3. Ennis, L.E.; Berry, H.M.; and Phillips, J.E. Dental roentgen ology, ed 6. Philadelphia, Lea & Febiger, 1967, p 410. 4. Ennis, L.E.; Berry, H.M.; and Phillips, J.E. Dental roent genology, ed 6. Philadelphia, Lea & Febiger, 1967, p 414. 5. Main, D.M.G. A mirror image double-tooth. Br Dent J 117:318 Oct 20, 1964. 6. Levitas, T.C. Gemination, fusion, twinning and concres cence. J Dent Child 32:93, 1965. 7. Fordyce, G.L. A case of bilateral gemination of maxillary incisors. Br Dent J 92:20 Jan 1, 1952. 8. Heslop, I.H. True gemination in posterior teeth. Br Dent J 97:93 Aug 17, 1954. 9. Paton, A.R.P., and Crighton, J.T. Bilateral gemination. A case report. Br Dent J 107:310 Nov 17, 1959. 10. Lowell, R.J., and Solomon, A.L. Fused teeth. JADA 68:762 May 1964. 11. Brook, A.H., and Winter, G.B. Double teeth. A retrospec tive study of “ geminated” and “ fused” teeth in children. Br Dent J 129:123 Aug 4, 1970. 12. Clem, W.H., and Natkin, E. Treatment of the fused tooth. Report of a case. Oral Surg 21:365 March 1966.
Comprehensive management of the double tooth: report of case
Allen B. Itkin, DDS
The malformed tooth often is a challenge to the dentist. It is frequently difficult to diagnose the specific developmental disturbance before the formation of a treatment plan to restore function and appearance. The anomalies that may have to be considered are those of the size of the crown, shape of the crown, root form, enamel and dentin formation, pulp and pulp canal morphology, and malposition of the tooth in the arch. The specific developmental defect must be evaluated objec tively to achieve an acceptable result from treat ment. A critical appraisal of the specific anom alies, rather than their classification into termin ology, will dictate the correct management.
Review of the literature The terms gemination, twinning, and fusion have been defined.1'3 Although some confusion still exists, these definitions are generally accepted. —Gemination: the attempt of a single tooth
bud to form two distinct morphologic entities. This may be represented clinically by two iden tical crowns joined in a midline to align in a mirror-image effect.4 Radiographically, the root may be singular with one canal. The tooth may occupy its normal position in the dental arch; however, because of the increased crown size of the tooth, crowding may exist if the adjacent teeth are present. —Twinning: gemination that was complete thus forming two identical adjacent teeth.5 —Fusion: the result of the joining of two ad jacent tooth buds. These can be either two nor mal buds or a normal and supernumerary bud. The clinical appearance would be of nonidentical crowns joined at a midline. Radiographically, two root canals and one or two roots may be evi dent. In many instances it is difficult to differentiate between the fused and geminated tooth.6 9 The term double tooth10 has been suggested to cover both of these possibilities when the true etiology cannot be determined. JADA, Vol. 90, June 1975 ■ 1269
f
:
\
F ig 1 ■ P re o p e ra tiv e clin ica l p h o t o g r a p h s h o w s a b n o r m a l right m a x illa ry
late ra l
incisor
with
o v e rla p pin g
of
central
incisors.
Report of case A 12-year-old girl was referred to us for evalua tion of an abnormally shaped tooth. The patient said that for the past few years she had been con cerned about the appearance of her mouth and teeth when she smiled. The past medical history was noncontributory. There was no history of trauma to the teeth or jaws. Physical examina tion showed a well-developed, well-nourished girl with no other physical abnormalities. Examination of the oral cavity revealed two abnormalities (Fig 1). First, the maxillary right lateral incisor was abnormally shaped. The tooth was unusually wide, measuring 11.5 mm at its greatest width. It was notched in the midline, and this gave it a double-image appearance. Sec ond, the maxillary central incisors were over lapped secondary to the crowding created by the large lateral incisor. Examination of the remain ing oral tissue showed no other abnormalities. Periapical (Fig 2), occlusal, and panoramic radiographs confirmed the previously mentioned dental abnormalities. The maxillary right lateral incisor had the appearance of two identical teeth joined from the apical third of the root to the crown and separating 2 mm cervical to the incisal edge. There were two pulp canals and chambers. The pulp chambers appeared to be connected. On May 9, 1973, the patient was premedicated with 5 mg of diazepam (Valium) intravenously, and local anesthesia was obtained with 2% lidocaine (Xylocaine) hydrochloride with 1:100,000 epinephrine. A mucoperiosteal flap was reflect ed from the gingival margin with lateral extension 1270 ■ JADA, Vol. 90, June 1975
F i g 2 ■ P r e o p e r a tiv e p eria p ica l ra d io g ra p h s h o w s t w o identical te eth a p p a r e n t l y j o in e d at m id lin e .
to the left lateral incisor and right cuspid. The crown of the double tooth was divided with a diamond bur. At this time the communication between pulp chambers was exposed. The roots then were sectioned by following a groove on their labial surface. There was no evidence of pulpal perforation as division of the root pro gressed. After division of the coronal two thirds of the root, the mesial root was removed from its socket. The remaining distal root was treated endodontically (Fig 3). The root and bone sur faces were smoothed with a diamond stone. The wound was irrigated with sterile saline solution
Fig 3
■ P h o t o g r a p h d u r in g s u rg e ry s h o w s s o c k e t w h e r e m esial
h a lf o f t o o t h w a s r e m o v e d
and
pulp
ch a m be r co m m unication.
Fig 5 ■ Radiograph taken in September shows bone deposi tion into mesial defect.
Fig 4 ■ Bony defect is seen in immediate postoperative radio graph.
and the flap closed with no. 4-0 black silk su tures. The patient tolerated the procedure with out difficulty. The immediate postoperative radiograph (Fig 4) showed a periodontal bony defect on the me sial aspect of the remaining tooth. One month postoperatively, it was evident that bone had started to fill the defect at the apical third. Re storative treatment was deferred for three months to permit additional bone deposition. On Sept 6, radiographs showed extensive bone deposition (Fig 5). There was no mobility of the tooth. Preparation for a cast gold post was initiated on Sept 24. At this time a maxillary Hawley appliance was inserted to correct the overlapping central incisors (Fig 6); this was ac complished in two months. The tooth then was prepared for a porcelain-fused-to-gold crown while the patient continued to wear the Hawley appliance without rubber bands to maintain posi tion. On March 22, the permanent crown was cemented (Fig 7).
Discussion The double tooth affords a striking clinical man ifestation of the differentiable and morphogen etic processes of tooth development. It challeng
Fig 6 ■ Hawley appliance in place to close space between lateral and central incisor.
Fig 7 ■ Final clinical photograph taken after completion of orthodontic and restorative treatment.
es us with the problems of defining its origin and restoring it to acceptable function and appear ance. The decision to split and remove a half of the double tooth was made with the thought of a mul tidisciplinary approach to achieve the desired Itkin—Barr: MANAGEMENT OF DOUBLE TOOTH ■ 1271
result. This took into consideration the need for surgical, endodontic, orthodontic, and restora tive treatment. The alternatives to this treatment all had obvious faults. Extraction would neces sitate prosthetic replacement, reshaping and crowning would not achieve the desired esthetic result,11 and no treatment would mean the per petuation the patient’s appearance. In planning the surgery for splitting, these principles should be closely followed. First, re flect full thickness periosteal flaps. Second, only a minimal amount o f labial bone should be re moved. Third, if pulp exposure occurs, complete endodontic treatment should be accomplished. Fourth, stabilization by splinting or wiring may be indicated if excessive mobility o f the remain ing tooth half exists.
Summary A patient with an abnormal maxillary lateral in cisor was treated to restore function and to im prove appearance. Although specific classifica tion o f the problem into accepted terminology was attempted, the term double tooth was used to define the patient’s problem. We have shown that the identification o f the specific abnormal ities, not the etiologic classification, is impor tant to achieve an effective treatment plan.
1272 ■ JADA, Vol. 90, June 1975
We thank Dr. Marlin Troiano, chairman, department of oral surgery, anesthesiology and hospital dental services, for re viewing this paper, and Dr. Harry Tuber, attending, Martland Hospital, and Dr. Richard Salb, general dentistry resident, Mart land Hospital, for their assistance with the restorative and orth odontic management of this patient. Dr. Itkin is clinical professor of oral surgery, anesthesiology, and hospital dental services and director of the division of oral surgery, Martland Hospital, College of Medicine and Dentistry of New Jersey. Dr. Barr is a resident in oral surgery at Martland Hospital, College of Medicine and Dentistry of New Jersey, New Jersey Medical School, 65 Bergen St, Newark, NJ 07107. Ad dress requests for reprints to Dr. Barr. 1. Shafer, W.G.; Hine, M.K.; and Levy, B.M. Textbook o f oral pathology, ed 3. Philadelphia, W. B. Saunders Co., 1974, p 35. 2. Bhaskar, S.N. Synopsis of oral pathology, ed 4. St. Louis, C. V. Mosby Co., 1973, p 29. 3. Ennis, L.E.; Berry, H.M.; and Phillips, J.E. Dental roentgen ology, ed 6. Philadelphia, Lea & Febiger, 1967, p 410. 4. Ennis, L.E.; Berry, H.M.; and Phillips, J.E. Dental roent genology, ed 6. Philadelphia, Lea & Febiger, 1967, p 414. 5. Main, D.M.G. A mirror image double-tooth. Br Dent J 117:318 Oct 20, 1964. 6. Levitas, T.C. Gemination, fusion, twinning and concres cence. J Dent Child 32:93, 1965. 7. Fordyce, G.L. A case of bilateral gemination of maxillary incisors. Br Dent J 92:20 Jan 1, 1952. 8. Heslop, I.H. True gemination in posterior teeth. Br Dent J 97:93 Aug 17, 1954. 9. Paton, A.R.P., and Crighton, J.T. Bilateral gemination. A case report. Br Dent J 107:310 Nov 17, 1959. 10. Lowell, R.J., and Solomon, A.L. Fused teeth. JADA 68:762 May 1964. 11. Brook, A.H., and Winter, G.B. Double teeth. A retrospec tive study of “ geminated” and “ fused” teeth in children. Br Dent J 129:123 Aug 4, 1970. 12. Clem, W.H., and Natkin, E. Treatment of the fused tooth. Report of a case. Oral Surg 21:365 March 1966.
