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Further Observations on Median Anterior Maxillary Cysts*
F U R T H E R O B S E R V A T IO N S O N M E D IA N A N T E R IO R M A X I L L A R Y CY STS* B y E D W A R D C . S T A F N E , D .D .S ., and L O U I E T . A U S T I N , D .D .S ., Rochester, M in n .
N a previous study1 of what Meyer has termed “ median anterior maxillary cysts,” three of these lesions were selected to illustrate the three types of epithelial lining. The roentgenograms of several cysts were shown. Th e cysts were of the size most commonly seen, and the statement was made that few cysts were encountered that were larger than those illustrated. It was suggested that these cysts do not tend to grow beyond certain limits because drainage of the contents to the surface may take place. Drainage may be constant or intermittent, and may be so scant that it cannot be detected grossly. It probably is readily estab lished because the bony cavity that the cyst occupies is not closed, but communi cates directly with the oral and nasal cavities. It is not difficult to conceive that, in some instances, the avenues of drainage may be completely closed, and the pressure from within the cyst may not be relieved; and, as a result, the cyst may continue to grow. It is not certain that this explanation for continued growth is correct; nevertheless, there is reason to believe that a few median anterior maxil lary cysts continue to grow and become very large. Median anterior maxillary cysts that have reached several centimeters in di ameter, but which are still fairly well confined to the median line, offer little difficulty in diagnosis. One that was rather large and yet had not involved any of the permanent teeth is shown in Fig ure; 1, a.
I
•From the Section on Dental Surgery, T he M ayo Clinic.
Jour. A .D .A . & D. Cos., Vol. 24, June 1937
REPORT OF CASES
C ase 1.—A man, aged 38, came to the clinic Sept. 28, 1935, complaining chiefly of a dermatitis, but also of swelling and pain directly posterior to the upper anterior teeth, from which there had been drainage on several occasions. Oral examination re vealed profuse drainage of pus. The roent genogram revealed the cyst shown in Fig ure 1, a, and a diagnosis of infected median anterior maxillary cyst was made. As it was thought advisable to postpone opera tion until the acute infection had sub sided, the cyst was not removed until October 10. The surgical approach for the removal of these cysts is, of course, from the surface of the palate, as this gives ac cess to the cyst, and there is little danger of injuring the permanent teeth. At opera tion, it was found that the infection had produced extensive destruction of the soft tissue on the surface of the palate. It was difficult to retract the tissue, and when it was retracted, the portion of the palatal bone overlying the cyst was found to have been destroyed and a large portion of the cyst was exposed. An attempt was made to remove the cyst intact, but it also had undergone such destruction by the infection that this was impossible. It was almost completely destroyed while being removed; which was discouraging, as evidence of what was probably an accessory cyst had been noted in the roentgenogram (Fig. 1, area designated by arrows), and satisfac tory microscopic sections probably would have demonstrated the presence of such a cyst. A good view of the bony cavity did show a definite concavity, almost 1 cm. deep, and situated to the left of the main cavity. There was no doubt that the con cavity was in direct communication with the main cavity. The occurrence of small
957
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The Journal of the American Dental Association and The Dental Cosmos
cysts in the walls of median anterior max illary cysts is characteristic, and the radiolucence in the lateral aspect of the image of the main cyst may be roentgenographic evidence of the budding of such a daughter cyst. If it is, the clinical picture is of un usual interest and extremely rare. Microscopic examination of some of the fragments of tissue removed revealed that the lesion was a cyst lined with squamous epithelium. Because of the extensive in flammation and destruction of palatal tis sue, the wound healed very slowly. A cyst which is slightly larger than that found in the previous case, but which had become sufficiently large to involve at least tw o of the permanent teeth is shown in Figure 1, b. T his cyst was still small enough to warrant a defi-
central incisors did not respond to tests for vitality. When the cyst, which was lined with epithelium, was removed, it was found that the bone surrounding the apices of the roots of the central incisors had been de stroyed, and one side of the root of the right lateral incisor was exposed. There was a perforation on the labial surface of the alveolar process, and also on the bony floor of the nose. The palatal surface of the alveolar process had undergone more extensive destruction. A line representing the original position of the anterior pala tine canal would have passed through the center of the cyst, which no doubt had its origin in the canal.
Fig. 1 .— a (Case 1), accessory cyst (indi cated by arrows) on left border of main cyst; b (Case 2 ), cyst.
nite roentgenographic diagnosis of median anterior maxillary cyst, although involve ment o f the permanent teeth confused the picture. Case 2.— A man, aged 55, who came to the Section on Dental Surgery, Aug. 26, 1935, had been experiencing a sensation of numbness in the region of the upper an terior teeth, and had noted a swelling on the labial surface of the alveolar process above the incisor teeth for about one year. There also was a swelling on the surface of the palate. No drainage from the cyst could be demonstrated and there was no evidence of previous drainage. The upper
Fig. 2 (Case 3).— Bite roentgenogram show ing cyst of maxilla.
W h en cysts become so extensive that they encroach on and involve many o f the permanent teeth, it is often difficult and sometimes impossible to establish their origin. T h e anterior palatine canal has been overlooked as a possible source, and it is probable that some of the large cysts of the maxilla are median anterior max illary cysts, one of which is illustrated in Figures 2 and 3. Case 3.— A man, aged 34, first came to the clinic Oct. 25, 1918. At that time, he had a lymphangioma removed from the
Stafne and Austin— Median Anterior Maxillary Cysts tongue. He returned, Aug. 30, 1934, for a general physical examination and surgical treatment for a pilonidal cyst. He was re ferred for a dental examination incidental to the general physical examination. Dental roentgenograms revealed a cyst of the max illa extending from the first molar region on one side across the midline and up to the first molar region on the opposite side. It had replaced much of the bone around the roots of teeth that were within its range and had extended well into the interdental septums. In view of its large size, one
959
epithelium-lined cyst which was continuous over the midline. In a consideration of the etiology of this cyst, the possibility that it was o f dental origin must be reckoned with. T h e first thing that comes to mind is a dental root cyst which may have developed from the roots of one or more of the perma nent teeth. T h e development o f such a cyst is invariably preceded by the death o f the pulp o f the teeth. It is, of course, also possible that the cyst could have had
Fig. 3 (Case 3).— Regular dental roentgenograms showing cyst.
Fig. 4.— a, dentigerous cyst associated with a left supernumerary central in cisor; b, develop ment o f dentigerous cyst on left supernumerary incisor and incipient cyst in anterior palatine can al; (Case 4) c, median anterior maxillary cyst and supernumerary central incisor.
would expect to find a marked enlargement over the external surface of the maxilla, but there was little evidence of its pres ence, except in the roentgenograms. There were no fillings nor caries in the teeth ap proximating the cyst. No pain had been experienced relative to these teeth, and there was no history to suggest that the pulps in any of them had been or were in fected. When the lesion was removed, Sept. 14, 1934, it was found to be a large single
its origin from one or both o f the missing bicuspid teeth; but if it had developed from only one o f these teeth, it probably w ould have been confined to the one side. I f both o f the missing bicuspid teeth had produced cysts, involvement o f both maxillae could be accounted for, but these cysts would remain as two separate lesions, while the one in question, even though very large, was a single cyst. T his
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The Journal of the American Dental Association and The Dental Cosmos
would also hold true if epithelial islands from the dental lamina or those associ ated with retained roots of deciduous teeth were considered as a possible source. That it was not a dentigerous cyst is cer tain, for there had not been nor were there any unerupted teeth. If the cyst had been lined with ciliated columnar epithelium, it might have been a para nasal sinus, although some median an terior maxillary cysts are also lined with this type of epithelium. This cyst was lined with squamous epithelium; which,
when one is prone to make a diagnosis of dentigerous cyst. In a previous article by one of us,2 attention was called to the fact that den tigerous cysts are frequently associated with mesiodens, this conclusion being based on ten instances in which there were mesiodens and also cysts in the an terior part of the maxilla. The possibility that the supernumerary teeth were not the source of all of these cysts was not then considered; but, in the light of present-day knowledge of cysts of the an-
Fig. 5.— Median anterior maxillary cyst and supernumerary right central incisor.
Fig. 6.— Large cyst which could be dentigerous, but which probably is a median anterior maxillary cyst.
together with the fact that the occur rence of cysts in the anterior palatine canal is common, suggests that we were dealing with a large median anterior maxillary cyst. A diagnosis of median anterior maxil lary cyst is sometimes made difficult by the presence of unerupted supernumerary central incisors (mesiodens), especially when they are superimposed on the image of the cyst in the roentgenogram, or have actually become included in the cyst;
terior maxillary region, one would be obliged to reconsider the diagnosis of dentigerous cyst in several of these cases. A review of the ten cysts referred to and others observed since that time affords evidence that some of them were median anterior maxillary cysts. There is, of course, no doubt that dentigerous cysts develop from mesiodens, for several such cysts have been seen in their incipient stage, or when sufficiently small to demonstrate a definite continuity
Stafne and Austin— Median Anterior Maxillary Cysts with the crowns of the teeth from which they developed. A cyst observed recently and which had developed from the enamel organ of an upper left supernu merary central incisor is shown in Figure 4, a. The cyst which extends distally is situated at some distance from the me dian line. There is no evidence of any enlargement o f the anterior palatine canal. That dentigerous and median anterior maxillary cysts may develop independ ently of each other in the same person is also possible. It is only when both cysts are still relatively small that this can be definitely demonstrated roentgenographically. The roentgenogram shown in Figure 4, b suggests such a condition. A definite dentigerous cyst has developed from the inverted upper left supernu merary central incisors, and the spherical shaped area of radiolucence seen between the two supernumerary teeth is evidence of a small cyst in the anterior palatine canal. It is possible that the two cysts may continue to grow extensively, be come superimposed one on the other and appear roentgenographically as one large cyst. It would then be impossible to see that the cysts had originated from two sources. In Figure 4, c is shown a cyst the roentgenographic appearance of which would alone warrant a rather definite diagnosis of median anterior maxillary cyst. It is of a size not uncommonly en countered and has been erroneously re ferred to in many textbooks as a large anterior palatine fossa. There is also a supernumerary tooth present, and it is this fact that prompts a report of the fol lowing case. C ase 4.—A man, aged 48, came to the clinic, Dec. 5, 1935, because of a urethral stricture. A dental examination was in cluded, and the dental roentgenogram re vealed a median anterior maxillary cyst and a supernumerary central incisor (Fig.
4, c). The patient was not aware of any drainage from the cyst, but a little drain age could be demonstrated at a point near the anterior palatine papilla when pressure was brought to bear on the palate. There was a slight swelling on the surface of the palate, but none on the labial surface of the alveolar process. The incisor teeth were free from caries and of normal color, and responded normally to tests for vitality. In view of the drainage, removal of the cyst was advised. The almost negligible danger of injuring the incisor teeth and the ease with which a cyst of this size can be re moved, if the proper surgical technic is followed, were also considered in making this decision. The cyst was removed Dec. 10, 1935. The soft palatal tissue was re tracted posteriorly to a point beyond the opening into the anterior palatine canal. The tissue that was retracted was carefully dissected away from the contents of the canal, which were firmly attached to the palatal tissue. The opening into the an terior palatine canal had to be enlarged very little to allow enucleation of the cyst. The walls of the round bony cavity that the cyst had occupied were smooth, and there was no communication with the in cisor teeth. The supernumerary tooth that had been noted in the roentgenogram could be distinctly felt within the cyst which was removed, but no part of it could be seen on the surface, although the apex of the root was very near the periphery. A post operative roentgenogram of the entire specimen would have been of interest, but this did not occur to us until after micro scopic sections had been made. The micro scopic examination revealed a cyst lined with squamous epithelium, and a small conical tooth in the wall of the cyst. The diagnosis of median anterior maxil lary cyst was verified at operation, when it was definitely demonstrated that it occu pied a cavity which was merely an enlarge ment of the anterior palatine canal, and which had been produced by the cyst. The situation of the cyst and the surgical tech nic for its removal were the same as in several cases in which median anterior maxillary cysts were removed previously.
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The Journal of the American Dental Association and The Dental Cosmos
The microscopic examination revealed the • apex of the left central incisor; which presence of nasopalatine vessels, nerves and introduces another etiologic factor and mucous glands in the walls of the cyst; a the possibility that this cyst is dentiger finding which has been described in pre ous. There was no evidence that it was vious microscopic studies of median ante a dental root cyst, for the teeth in the rior maxillary cysts. region of the cyst were free from caries, COMMENT and all o f ' the teeth were present with A diagnosis of median anterior maxil the exception of the upper right first bi lary cyst having been established, it is cuspid. The root of this tooth was still interesting to try to account for the pres present at a point near the crest of the ence of the supernumerary tooth within alveolar ridge, but it was separated from the cyst. It is almost certain that it did and not involved by the cyst. Several years ago, one would probably not originate or develop within the an terior palatine, canal, a situation which have said with considerable assurance is between but not within either maxilla, that this was a dentigerous cyst which although it is possible that it could erupt had its origin from the supernumerary into the anterior palatine canal. The tooth, but such a diagnosis would un most plausible explanation is that a cyst doubtedly be questioned now that more which had origin in the anterior palatine is known of median anterior maxillary canal continued to grow and envelop the 'cysts, and particularly since Meyer3 has small1tooth that was situated near the called attention to the frequency of their canal. occurrence. It is not difficult to conceive In Figure 5 is shown what formerly that this cyst had its origin in the ante would have been considered a dentiger rior palatine canal, for it extended into ous cyst associated with the supernu both maxillae, and one would probably merary tooth seen on the right of the be justified in favoring a diagnosis of median line; but, in this case, it also is median anterior maxillary cyst. possible that it is a median anterior SUMMARY maxillary cyst which encroached on the W hile small median anterior maxillary tooth. The marked separation of the roots of the central incisors suggests that cysts should present no difficulty in diag pressure from the cyst was first exerted nosis, those of extensive size d o; for at that point as it grew and extended lat when they have encroached on the roots erally to both sides. Any separation of of the teeth, it may be impossible to dis the permanent teeth caused by a cyst tinguish them from dental root cysts. which had its origin from the supernu Median anterior maxillary cysts do oc merary tooth would be likely to take casionally attain considerable size, and place between the right central and lat probably some of the large cysts of the eral incisors or between the right lateral maxilla whose etiology is obscure should incisor and cuspid. It is also very doubt be thus classified. There is no doubt that ful that such a cyst would have extended dentigerous cysts develop in association across the median line and so far to the with supernumerary central incisors left. On the contrary, it probably would (mesiodens). The presence of a super have been confined to the right maxilla. numerary tooth and a large cyst in the T h e roentgenographic appearance of anterior part of the maxilla is not con the cyst shown in Figure 6 is very similar clusive proof that the cyst is dentigerous. to that shown in Figure 3. There is an In some instances, median anterior max unerupted supernumerary tooth near the illary cysts continue to grow, and en-
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Belding and Belding— Oral Flora
Cysts.” J. A . D . A ., 2 3:801-809, M ay 1936. 2. Stafn e , E. C .: “ Supernumerary Upper Central Incisors.” D . Cosmos, 7 3 :976-980, Octo ber 1931. BIBLIOGRAPHY 3. M eyer , A . W . : “M edian Anterior M a x 1. St afn e , E. C .; A ustin , L. T ., and illary Cysts.” J. A . D . A ., 18:1851-1877, Octo G ardner , B. S .: “M edian Anterior M axillary ber 1931.
croach on or envelop unerupted super numerary teeth, the presence of which are merely coincidental.
O R A L FLORA B y P . H . B E L D I N G , D .D .S ., and L . J. B E L D I N G , M .D ., W a u c o m a , Iow a
H E accompanying photomicrographs are submitted in the hope that they will save much time and speculation for those who are endeavoring to grow
T
the oral cavity and grown aerobically. It is extremely pleomorphic and illustrates that many of the coccidoid forms found in the oral cavity may be transitional
Appearance of culture from age of 24 hours (above, left) to age of 10 days (below, right).
the members of the oral flora in pure culture. The organism was isolated from Jour. A .D .A . & D. Cos., Vol. 24, June 1937
forms in the life cycle of pleomorphic organisms.
N a previous study1 of what Meyer has termed “ median anterior maxillary cysts,” three of these lesions were selected to illustrate the three types of epithelial lining. The roentgenograms of several cysts were shown. Th e cysts were of the size most commonly seen, and the statement was made that few cysts were encountered that were larger than those illustrated. It was suggested that these cysts do not tend to grow beyond certain limits because drainage of the contents to the surface may take place. Drainage may be constant or intermittent, and may be so scant that it cannot be detected grossly. It probably is readily estab lished because the bony cavity that the cyst occupies is not closed, but communi cates directly with the oral and nasal cavities. It is not difficult to conceive that, in some instances, the avenues of drainage may be completely closed, and the pressure from within the cyst may not be relieved; and, as a result, the cyst may continue to grow. It is not certain that this explanation for continued growth is correct; nevertheless, there is reason to believe that a few median anterior maxil lary cysts continue to grow and become very large. Median anterior maxillary cysts that have reached several centimeters in di ameter, but which are still fairly well confined to the median line, offer little difficulty in diagnosis. One that was rather large and yet had not involved any of the permanent teeth is shown in Fig ure; 1, a.
I
•From the Section on Dental Surgery, T he M ayo Clinic.
Jour. A .D .A . & D. Cos., Vol. 24, June 1937
REPORT OF CASES
C ase 1.—A man, aged 38, came to the clinic Sept. 28, 1935, complaining chiefly of a dermatitis, but also of swelling and pain directly posterior to the upper anterior teeth, from which there had been drainage on several occasions. Oral examination re vealed profuse drainage of pus. The roent genogram revealed the cyst shown in Fig ure 1, a, and a diagnosis of infected median anterior maxillary cyst was made. As it was thought advisable to postpone opera tion until the acute infection had sub sided, the cyst was not removed until October 10. The surgical approach for the removal of these cysts is, of course, from the surface of the palate, as this gives ac cess to the cyst, and there is little danger of injuring the permanent teeth. At opera tion, it was found that the infection had produced extensive destruction of the soft tissue on the surface of the palate. It was difficult to retract the tissue, and when it was retracted, the portion of the palatal bone overlying the cyst was found to have been destroyed and a large portion of the cyst was exposed. An attempt was made to remove the cyst intact, but it also had undergone such destruction by the infection that this was impossible. It was almost completely destroyed while being removed; which was discouraging, as evidence of what was probably an accessory cyst had been noted in the roentgenogram (Fig. 1, area designated by arrows), and satisfac tory microscopic sections probably would have demonstrated the presence of such a cyst. A good view of the bony cavity did show a definite concavity, almost 1 cm. deep, and situated to the left of the main cavity. There was no doubt that the con cavity was in direct communication with the main cavity. The occurrence of small
957
958
The Journal of the American Dental Association and The Dental Cosmos
cysts in the walls of median anterior max illary cysts is characteristic, and the radiolucence in the lateral aspect of the image of the main cyst may be roentgenographic evidence of the budding of such a daughter cyst. If it is, the clinical picture is of un usual interest and extremely rare. Microscopic examination of some of the fragments of tissue removed revealed that the lesion was a cyst lined with squamous epithelium. Because of the extensive in flammation and destruction of palatal tis sue, the wound healed very slowly. A cyst which is slightly larger than that found in the previous case, but which had become sufficiently large to involve at least tw o of the permanent teeth is shown in Figure 1, b. T his cyst was still small enough to warrant a defi-
central incisors did not respond to tests for vitality. When the cyst, which was lined with epithelium, was removed, it was found that the bone surrounding the apices of the roots of the central incisors had been de stroyed, and one side of the root of the right lateral incisor was exposed. There was a perforation on the labial surface of the alveolar process, and also on the bony floor of the nose. The palatal surface of the alveolar process had undergone more extensive destruction. A line representing the original position of the anterior pala tine canal would have passed through the center of the cyst, which no doubt had its origin in the canal.
Fig. 1 .— a (Case 1), accessory cyst (indi cated by arrows) on left border of main cyst; b (Case 2 ), cyst.
nite roentgenographic diagnosis of median anterior maxillary cyst, although involve ment o f the permanent teeth confused the picture. Case 2.— A man, aged 55, who came to the Section on Dental Surgery, Aug. 26, 1935, had been experiencing a sensation of numbness in the region of the upper an terior teeth, and had noted a swelling on the labial surface of the alveolar process above the incisor teeth for about one year. There also was a swelling on the surface of the palate. No drainage from the cyst could be demonstrated and there was no evidence of previous drainage. The upper
Fig. 2 (Case 3).— Bite roentgenogram show ing cyst of maxilla.
W h en cysts become so extensive that they encroach on and involve many o f the permanent teeth, it is often difficult and sometimes impossible to establish their origin. T h e anterior palatine canal has been overlooked as a possible source, and it is probable that some of the large cysts of the maxilla are median anterior max illary cysts, one of which is illustrated in Figures 2 and 3. Case 3.— A man, aged 34, first came to the clinic Oct. 25, 1918. At that time, he had a lymphangioma removed from the
Stafne and Austin— Median Anterior Maxillary Cysts tongue. He returned, Aug. 30, 1934, for a general physical examination and surgical treatment for a pilonidal cyst. He was re ferred for a dental examination incidental to the general physical examination. Dental roentgenograms revealed a cyst of the max illa extending from the first molar region on one side across the midline and up to the first molar region on the opposite side. It had replaced much of the bone around the roots of teeth that were within its range and had extended well into the interdental septums. In view of its large size, one
959
epithelium-lined cyst which was continuous over the midline. In a consideration of the etiology of this cyst, the possibility that it was o f dental origin must be reckoned with. T h e first thing that comes to mind is a dental root cyst which may have developed from the roots of one or more of the perma nent teeth. T h e development o f such a cyst is invariably preceded by the death o f the pulp o f the teeth. It is, of course, also possible that the cyst could have had
Fig. 3 (Case 3).— Regular dental roentgenograms showing cyst.
Fig. 4.— a, dentigerous cyst associated with a left supernumerary central in cisor; b, develop ment o f dentigerous cyst on left supernumerary incisor and incipient cyst in anterior palatine can al; (Case 4) c, median anterior maxillary cyst and supernumerary central incisor.
would expect to find a marked enlargement over the external surface of the maxilla, but there was little evidence of its pres ence, except in the roentgenograms. There were no fillings nor caries in the teeth ap proximating the cyst. No pain had been experienced relative to these teeth, and there was no history to suggest that the pulps in any of them had been or were in fected. When the lesion was removed, Sept. 14, 1934, it was found to be a large single
its origin from one or both o f the missing bicuspid teeth; but if it had developed from only one o f these teeth, it probably w ould have been confined to the one side. I f both o f the missing bicuspid teeth had produced cysts, involvement o f both maxillae could be accounted for, but these cysts would remain as two separate lesions, while the one in question, even though very large, was a single cyst. T his
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The Journal of the American Dental Association and The Dental Cosmos
would also hold true if epithelial islands from the dental lamina or those associ ated with retained roots of deciduous teeth were considered as a possible source. That it was not a dentigerous cyst is cer tain, for there had not been nor were there any unerupted teeth. If the cyst had been lined with ciliated columnar epithelium, it might have been a para nasal sinus, although some median an terior maxillary cysts are also lined with this type of epithelium. This cyst was lined with squamous epithelium; which,
when one is prone to make a diagnosis of dentigerous cyst. In a previous article by one of us,2 attention was called to the fact that den tigerous cysts are frequently associated with mesiodens, this conclusion being based on ten instances in which there were mesiodens and also cysts in the an terior part of the maxilla. The possibility that the supernumerary teeth were not the source of all of these cysts was not then considered; but, in the light of present-day knowledge of cysts of the an-
Fig. 5.— Median anterior maxillary cyst and supernumerary right central incisor.
Fig. 6.— Large cyst which could be dentigerous, but which probably is a median anterior maxillary cyst.
together with the fact that the occur rence of cysts in the anterior palatine canal is common, suggests that we were dealing with a large median anterior maxillary cyst. A diagnosis of median anterior maxil lary cyst is sometimes made difficult by the presence of unerupted supernumerary central incisors (mesiodens), especially when they are superimposed on the image of the cyst in the roentgenogram, or have actually become included in the cyst;
terior maxillary region, one would be obliged to reconsider the diagnosis of dentigerous cyst in several of these cases. A review of the ten cysts referred to and others observed since that time affords evidence that some of them were median anterior maxillary cysts. There is, of course, no doubt that dentigerous cysts develop from mesiodens, for several such cysts have been seen in their incipient stage, or when sufficiently small to demonstrate a definite continuity
Stafne and Austin— Median Anterior Maxillary Cysts with the crowns of the teeth from which they developed. A cyst observed recently and which had developed from the enamel organ of an upper left supernu merary central incisor is shown in Figure 4, a. The cyst which extends distally is situated at some distance from the me dian line. There is no evidence of any enlargement o f the anterior palatine canal. That dentigerous and median anterior maxillary cysts may develop independ ently of each other in the same person is also possible. It is only when both cysts are still relatively small that this can be definitely demonstrated roentgenographically. The roentgenogram shown in Figure 4, b suggests such a condition. A definite dentigerous cyst has developed from the inverted upper left supernu merary central incisors, and the spherical shaped area of radiolucence seen between the two supernumerary teeth is evidence of a small cyst in the anterior palatine canal. It is possible that the two cysts may continue to grow extensively, be come superimposed one on the other and appear roentgenographically as one large cyst. It would then be impossible to see that the cysts had originated from two sources. In Figure 4, c is shown a cyst the roentgenographic appearance of which would alone warrant a rather definite diagnosis of median anterior maxillary cyst. It is of a size not uncommonly en countered and has been erroneously re ferred to in many textbooks as a large anterior palatine fossa. There is also a supernumerary tooth present, and it is this fact that prompts a report of the fol lowing case. C ase 4.—A man, aged 48, came to the clinic, Dec. 5, 1935, because of a urethral stricture. A dental examination was in cluded, and the dental roentgenogram re vealed a median anterior maxillary cyst and a supernumerary central incisor (Fig.
4, c). The patient was not aware of any drainage from the cyst, but a little drain age could be demonstrated at a point near the anterior palatine papilla when pressure was brought to bear on the palate. There was a slight swelling on the surface of the palate, but none on the labial surface of the alveolar process. The incisor teeth were free from caries and of normal color, and responded normally to tests for vitality. In view of the drainage, removal of the cyst was advised. The almost negligible danger of injuring the incisor teeth and the ease with which a cyst of this size can be re moved, if the proper surgical technic is followed, were also considered in making this decision. The cyst was removed Dec. 10, 1935. The soft palatal tissue was re tracted posteriorly to a point beyond the opening into the anterior palatine canal. The tissue that was retracted was carefully dissected away from the contents of the canal, which were firmly attached to the palatal tissue. The opening into the an terior palatine canal had to be enlarged very little to allow enucleation of the cyst. The walls of the round bony cavity that the cyst had occupied were smooth, and there was no communication with the in cisor teeth. The supernumerary tooth that had been noted in the roentgenogram could be distinctly felt within the cyst which was removed, but no part of it could be seen on the surface, although the apex of the root was very near the periphery. A post operative roentgenogram of the entire specimen would have been of interest, but this did not occur to us until after micro scopic sections had been made. The micro scopic examination revealed a cyst lined with squamous epithelium, and a small conical tooth in the wall of the cyst. The diagnosis of median anterior maxil lary cyst was verified at operation, when it was definitely demonstrated that it occu pied a cavity which was merely an enlarge ment of the anterior palatine canal, and which had been produced by the cyst. The situation of the cyst and the surgical tech nic for its removal were the same as in several cases in which median anterior maxillary cysts were removed previously.
962
The Journal of the American Dental Association and The Dental Cosmos
The microscopic examination revealed the • apex of the left central incisor; which presence of nasopalatine vessels, nerves and introduces another etiologic factor and mucous glands in the walls of the cyst; a the possibility that this cyst is dentiger finding which has been described in pre ous. There was no evidence that it was vious microscopic studies of median ante a dental root cyst, for the teeth in the rior maxillary cysts. region of the cyst were free from caries, COMMENT and all o f ' the teeth were present with A diagnosis of median anterior maxil the exception of the upper right first bi lary cyst having been established, it is cuspid. The root of this tooth was still interesting to try to account for the pres present at a point near the crest of the ence of the supernumerary tooth within alveolar ridge, but it was separated from the cyst. It is almost certain that it did and not involved by the cyst. Several years ago, one would probably not originate or develop within the an terior palatine, canal, a situation which have said with considerable assurance is between but not within either maxilla, that this was a dentigerous cyst which although it is possible that it could erupt had its origin from the supernumerary into the anterior palatine canal. The tooth, but such a diagnosis would un most plausible explanation is that a cyst doubtedly be questioned now that more which had origin in the anterior palatine is known of median anterior maxillary canal continued to grow and envelop the 'cysts, and particularly since Meyer3 has small1tooth that was situated near the called attention to the frequency of their canal. occurrence. It is not difficult to conceive In Figure 5 is shown what formerly that this cyst had its origin in the ante would have been considered a dentiger rior palatine canal, for it extended into ous cyst associated with the supernu both maxillae, and one would probably merary tooth seen on the right of the be justified in favoring a diagnosis of median line; but, in this case, it also is median anterior maxillary cyst. possible that it is a median anterior SUMMARY maxillary cyst which encroached on the W hile small median anterior maxillary tooth. The marked separation of the roots of the central incisors suggests that cysts should present no difficulty in diag pressure from the cyst was first exerted nosis, those of extensive size d o; for at that point as it grew and extended lat when they have encroached on the roots erally to both sides. Any separation of of the teeth, it may be impossible to dis the permanent teeth caused by a cyst tinguish them from dental root cysts. which had its origin from the supernu Median anterior maxillary cysts do oc merary tooth would be likely to take casionally attain considerable size, and place between the right central and lat probably some of the large cysts of the eral incisors or between the right lateral maxilla whose etiology is obscure should incisor and cuspid. It is also very doubt be thus classified. There is no doubt that ful that such a cyst would have extended dentigerous cysts develop in association across the median line and so far to the with supernumerary central incisors left. On the contrary, it probably would (mesiodens). The presence of a super have been confined to the right maxilla. numerary tooth and a large cyst in the T h e roentgenographic appearance of anterior part of the maxilla is not con the cyst shown in Figure 6 is very similar clusive proof that the cyst is dentigerous. to that shown in Figure 3. There is an In some instances, median anterior max unerupted supernumerary tooth near the illary cysts continue to grow, and en-
963
Belding and Belding— Oral Flora
Cysts.” J. A . D . A ., 2 3:801-809, M ay 1936. 2. Stafn e , E. C .: “ Supernumerary Upper Central Incisors.” D . Cosmos, 7 3 :976-980, Octo ber 1931. BIBLIOGRAPHY 3. M eyer , A . W . : “M edian Anterior M a x 1. St afn e , E. C .; A ustin , L. T ., and illary Cysts.” J. A . D . A ., 18:1851-1877, Octo G ardner , B. S .: “M edian Anterior M axillary ber 1931.
croach on or envelop unerupted super numerary teeth, the presence of which are merely coincidental.
O R A L FLORA B y P . H . B E L D I N G , D .D .S ., and L . J. B E L D I N G , M .D ., W a u c o m a , Iow a
H E accompanying photomicrographs are submitted in the hope that they will save much time and speculation for those who are endeavoring to grow
T
the oral cavity and grown aerobically. It is extremely pleomorphic and illustrates that many of the coccidoid forms found in the oral cavity may be transitional
Appearance of culture from age of 24 hours (above, left) to age of 10 days (below, right).
the members of the oral flora in pure culture. The organism was isolated from Jour. A .D .A . & D. Cos., Vol. 24, June 1937
forms in the life cycle of pleomorphic organisms.