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Incisive Canal Cysts*
INCISIVE CANAL CYSTS* B y R. P.
G in g r a s s,
M .D ., D .D .S., M ilwaukee, Wis.
E Y E R 1 made the first report of an incisive canal cyst in 1914. Schroff,2 in 1930, reported four cases. M eyer,3 in 1931, reported an in cidence o f one in sixty-six, as determined by dissection o f 600 cadavers. Stafne el al.4 report an incidence of not less than one in every hundred patients. The
M
T h e following case histories emphasize some points that m ay aid the general practitioner in the diagnosis and treat ment o f this type o f cyst. RE PO RT O F GASES
C ase i .— A girl, aged 19, was referred for dental diagnosis because of an intermittent
Fig. 1.— Incisive canal cyst in girl aged 19. A radiolucent area about 8 mm. in diameter is seen between the apices of the upper central incisors. The pulps of these teeth responded in a normal w ay to the electric pulp tests.
Fig. 2.— Incisive canal cyst in girl aged 9. The history of the case was essentially the same as in Case 1. The roentgen appearance was not definitely that of a cyst. Pulp responses were normal.
diagnosis was made roentgenologically. T h a t the diagnosis o f an incisive canal cyst is not easy in m any cases, especially when the cyst is small and when it contains an unerupted or supernumerary tooth, is emphasized by Stafne and Austin.5 *Synonyms: Median cysts; nasopalatine cysts.
anterior
Jour. A .D .A ., Vol. 27, January 1940
maxillary
discharge of a small amount of pus from the region of the upper central incisors on the palatal side. The patient had been aware of the condition for the past year. On exami nation, no swelling was present. The mucous membrane was slightly reddened in the re gion of the incisive papilla. When the area was palpated, a small amount of pus es caped through a fistulous opening by the side of the papilla. Roentgenologic examina
96
Gingrass— Incisive C an al Cysts
tion (Fig. i) revealed, between the apices of the central incisor teeth, a round radiolucent area which could be identified as a large incisive canal. However, in consideration of the history and physical findings, a diagnosis of incisive canal cyst must be made. At oper ation, a palatal flap was reflected and the contents of the canal were removed. No attempt was made to preserve the nasopala tine nerves and vessels. The canal was about 8 mm. in diameter. The microscopic diagno sis was epithelial cyst. C a se 2.— A girl, aged 9, came in with the
Fig. 3.— Incisive canal cyst in edentulous jaw of man aged 45. T he teeth had been ex tracted two years previously. The patient was wearing a denture part of the time. The radio paque shadow, partially obscuring the cyst, is caused by the nasal septum.
97 The significance of this area was not realized until after operation. In view of the clinical findings and previous experience, a diagnosis of incisive canal cyst was made and opera tion was recommended. Under general anes thesia, a palatal flap was reflected. Free pus escaped before the flap was completely re flected, the cyst apparently having been rup tured. The incisive canal was about 1 cm. in diameter. The contents were completely removed and the flap was sutured. C a se 3.— A man, aged 45, came in with the complaint of a periodic swelling and dis charge of pus from the region of the upper right central incisor alveolus of six months’ duration. Physical examination revealed a fistula on the crest of the ridge in the region of the upper right central incisor alveolus. Roentgenologic examination (Fig. 3) dis closed an incisive canal cyst about 1.5 cm. in diameter. The cyst was completely enu cleated under local anesthesia. C a se 4.— A woman, aged 73, consulted the dentist because of swelling and pain which suddenly developed in the anterior part of the upper jaw. The patient’s teeth had been extracted about five years previously. The dentist incised the swelling and there fol lowed a free discharge of pus. Physical ex amination revealed a swelling almost obliter ating the mucofold in the upper anterior
Fig. 4.— Cyst in woman aged 73. The central position of the cyst is suggestive of an origin in the incisive canal.
complaint of an intermittent discharge of a small amount of pus from the region of the incisive papilla, which had been present for three years. The area had been lanced sev eral times. There was a discharge of a few drops of pus on pressure over the region of the incisive papilla. Roentgenologic exami nation (Fig. 2) revealed no radiolucent area between the apices of the upper central in cisors, but a round area of increased density.
region and which had an eggshell crackle on palpation. Pus was discharging from the in cision. Roentgenologic examination (Fig. 4) revealed a large cyst in the median portion of the jaw, with the greater part of the cyst extending to the left. As the patient’s gen eral condition was very poor, palliative treat ment only was carried out. C ase 5.— A man, aged 70, was referred for attention because of a cyst in the upper jaw .
98
T h e jo u rn a l o f the Am erican D en ta l Association
The upper anterior teeth had been extracted two months previously. Pus continued to dis charge from the left lateral incisor alveolus. Physical examination revealed swelling on the palate in the anterior part about the size of a walnut. Pressure on this area caused pus to be discharged through the left lateral in cisor alveolus. Roentgen examination (Fig. 5) revealed a large cyst occupying the an terior part of the maxillae. The cyst ex tended laterad and dorsad as far as the antra. The microscopic diagnosis was epithelial cyst.
can identify the incisive canal and oc casionally smaller canals within it. When the cysts are large, we have been unable to see anything that looks like an in cisive canal. T h e treatment of an in cisive canal cyst is the same as for any cyst. B IB L IO G R A P H Y
1. M e y e r , A. W .: Spolia Anatomica: Unique Supernumerary Para-Nasal Sinus D i rectly Above Superior Incisors. /. Anat. & Physiol., 48 , January 1914, pp. 118-120.
Fig- 5 -— Cyst in man aged 70. As in Figure 4, the larger the cyst becomes, the more difficult it is to determine its origin. COM M ENT
Incisive canal cysts are not so unusual as was formerly believed. T h ey arise, it is believed, from epithelial remnants from the nasopalatine duct. Embryologic data on the nasopalatine duct are meager. Difficulty in diagnosis arises when the cyst has reached a large size or contains an unerupted or a supernumerary tooth. It m ay then be confused with a radicular or a dentigerous cyst, when it involves the median anterior m axillary region. When incisive canal cysts are small we
2. S c h r o f f , J o s e p h : Cysts in Incisor C a nal: Further Studies of Pathologic Conditions in Region of Nasopalatine (Incisor) Canal and Papilla Palatina. ]. D. Res., 10:739-762, December 1930. 3 . M e y e r , A. W .: Median Anterior M axil lary Cysts. J.A .D .A ., 8 1 : 1 8 5 1 - 1 8 7 7 , October
I93I4.
S t a f n e , E. C. ; A u s t i n , L. T ., and G a r d B. S . : Median Anterior M axillary Cysts. J.A .D .A ., 2 3 : 8 0 1 - 8 0 9 , M ay 1 9 3 6 5 . S t a f n e , E. C., and A u s t i n , L. T .: Further Observations on Median Anterior M axillary Cysts. J.A .D .A ., 2 4 : 9 5 7 - 9 6 3 , June 1937 208 East Wisconsin Avenue. ner,
G in g r a s s,
M .D ., D .D .S., M ilwaukee, Wis.
E Y E R 1 made the first report of an incisive canal cyst in 1914. Schroff,2 in 1930, reported four cases. M eyer,3 in 1931, reported an in cidence o f one in sixty-six, as determined by dissection o f 600 cadavers. Stafne el al.4 report an incidence of not less than one in every hundred patients. The
M
T h e following case histories emphasize some points that m ay aid the general practitioner in the diagnosis and treat ment o f this type o f cyst. RE PO RT O F GASES
C ase i .— A girl, aged 19, was referred for dental diagnosis because of an intermittent
Fig. 1.— Incisive canal cyst in girl aged 19. A radiolucent area about 8 mm. in diameter is seen between the apices of the upper central incisors. The pulps of these teeth responded in a normal w ay to the electric pulp tests.
Fig. 2.— Incisive canal cyst in girl aged 9. The history of the case was essentially the same as in Case 1. The roentgen appearance was not definitely that of a cyst. Pulp responses were normal.
diagnosis was made roentgenologically. T h a t the diagnosis o f an incisive canal cyst is not easy in m any cases, especially when the cyst is small and when it contains an unerupted or supernumerary tooth, is emphasized by Stafne and Austin.5 *Synonyms: Median cysts; nasopalatine cysts.
anterior
Jour. A .D .A ., Vol. 27, January 1940
maxillary
discharge of a small amount of pus from the region of the upper central incisors on the palatal side. The patient had been aware of the condition for the past year. On exami nation, no swelling was present. The mucous membrane was slightly reddened in the re gion of the incisive papilla. When the area was palpated, a small amount of pus es caped through a fistulous opening by the side of the papilla. Roentgenologic examina
96
Gingrass— Incisive C an al Cysts
tion (Fig. i) revealed, between the apices of the central incisor teeth, a round radiolucent area which could be identified as a large incisive canal. However, in consideration of the history and physical findings, a diagnosis of incisive canal cyst must be made. At oper ation, a palatal flap was reflected and the contents of the canal were removed. No attempt was made to preserve the nasopala tine nerves and vessels. The canal was about 8 mm. in diameter. The microscopic diagno sis was epithelial cyst. C a se 2.— A girl, aged 9, came in with the
Fig. 3.— Incisive canal cyst in edentulous jaw of man aged 45. T he teeth had been ex tracted two years previously. The patient was wearing a denture part of the time. The radio paque shadow, partially obscuring the cyst, is caused by the nasal septum.
97 The significance of this area was not realized until after operation. In view of the clinical findings and previous experience, a diagnosis of incisive canal cyst was made and opera tion was recommended. Under general anes thesia, a palatal flap was reflected. Free pus escaped before the flap was completely re flected, the cyst apparently having been rup tured. The incisive canal was about 1 cm. in diameter. The contents were completely removed and the flap was sutured. C a se 3.— A man, aged 45, came in with the complaint of a periodic swelling and dis charge of pus from the region of the upper right central incisor alveolus of six months’ duration. Physical examination revealed a fistula on the crest of the ridge in the region of the upper right central incisor alveolus. Roentgenologic examination (Fig. 3) dis closed an incisive canal cyst about 1.5 cm. in diameter. The cyst was completely enu cleated under local anesthesia. C a se 4.— A woman, aged 73, consulted the dentist because of swelling and pain which suddenly developed in the anterior part of the upper jaw. The patient’s teeth had been extracted about five years previously. The dentist incised the swelling and there fol lowed a free discharge of pus. Physical ex amination revealed a swelling almost obliter ating the mucofold in the upper anterior
Fig. 4.— Cyst in woman aged 73. The central position of the cyst is suggestive of an origin in the incisive canal.
complaint of an intermittent discharge of a small amount of pus from the region of the incisive papilla, which had been present for three years. The area had been lanced sev eral times. There was a discharge of a few drops of pus on pressure over the region of the incisive papilla. Roentgenologic exami nation (Fig. 2) revealed no radiolucent area between the apices of the upper central in cisors, but a round area of increased density.
region and which had an eggshell crackle on palpation. Pus was discharging from the in cision. Roentgenologic examination (Fig. 4) revealed a large cyst in the median portion of the jaw, with the greater part of the cyst extending to the left. As the patient’s gen eral condition was very poor, palliative treat ment only was carried out. C ase 5.— A man, aged 70, was referred for attention because of a cyst in the upper jaw .
98
T h e jo u rn a l o f the Am erican D en ta l Association
The upper anterior teeth had been extracted two months previously. Pus continued to dis charge from the left lateral incisor alveolus. Physical examination revealed swelling on the palate in the anterior part about the size of a walnut. Pressure on this area caused pus to be discharged through the left lateral in cisor alveolus. Roentgen examination (Fig. 5) revealed a large cyst occupying the an terior part of the maxillae. The cyst ex tended laterad and dorsad as far as the antra. The microscopic diagnosis was epithelial cyst.
can identify the incisive canal and oc casionally smaller canals within it. When the cysts are large, we have been unable to see anything that looks like an in cisive canal. T h e treatment of an in cisive canal cyst is the same as for any cyst. B IB L IO G R A P H Y
1. M e y e r , A. W .: Spolia Anatomica: Unique Supernumerary Para-Nasal Sinus D i rectly Above Superior Incisors. /. Anat. & Physiol., 48 , January 1914, pp. 118-120.
Fig- 5 -— Cyst in man aged 70. As in Figure 4, the larger the cyst becomes, the more difficult it is to determine its origin. COM M ENT
Incisive canal cysts are not so unusual as was formerly believed. T h ey arise, it is believed, from epithelial remnants from the nasopalatine duct. Embryologic data on the nasopalatine duct are meager. Difficulty in diagnosis arises when the cyst has reached a large size or contains an unerupted or a supernumerary tooth. It m ay then be confused with a radicular or a dentigerous cyst, when it involves the median anterior m axillary region. When incisive canal cysts are small we
2. S c h r o f f , J o s e p h : Cysts in Incisor C a nal: Further Studies of Pathologic Conditions in Region of Nasopalatine (Incisor) Canal and Papilla Palatina. ]. D. Res., 10:739-762, December 1930. 3 . M e y e r , A. W .: Median Anterior M axil lary Cysts. J.A .D .A ., 8 1 : 1 8 5 1 - 1 8 7 7 , October
I93I4.
S t a f n e , E. C. ; A u s t i n , L. T ., and G a r d B. S . : Median Anterior M axillary Cysts. J.A .D .A ., 2 3 : 8 0 1 - 8 0 9 , M ay 1 9 3 6 5 . S t a f n e , E. C., and A u s t i n , L. T .: Further Observations on Median Anterior M axillary Cysts. J.A .D .A ., 2 4 : 9 5 7 - 9 6 3 , June 1937 208 East Wisconsin Avenue. ner,