SciELO - Scientific Electronic Library Online

 
vol.10 número2Tumor pardo en la sínfisis mandibular como primera manifestación clínica de hiperparatiroidismo: diagnóstico y tratamientoMucocele de la glandula submaxilar: a propósito de un caso índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados

Journal

Artigo

Indicadores

Links relacionados

Compartilhar


Medicina Oral, Patología Oral y Cirugía Bucal (Ed. impresa)

versão impressa ISSN 1698-4447

Med. oral patol. oral cir. bucal (Ed.impr.) vol.10 no.2  Mar./Abr. 2005

 

A Stafne's cavity with unusual location in the mandibular anterior area
Cavidad de Stafne de localización inusual en el sector anterior mandibular

 

Rodolfo Belmonte Caro (1), Maria José Vélez Gutiérrez (2), Francisco Javier García De La Vega Sosa (3),
Alberto García-Perla García (4), Pedro A. Infante Cossío (5), José María Díaz Fernández (6), Eusebio Torres Carranza (6)

(1) Cirujano Oral y Maxilofacial. Médico Adjunto Servicio de Cirugía Oral y Maxilofacial HH.UU.
"Virgen del Rocío" de Sevilla. Médico Estomatólogo
(2) Odontólogo. Master en Cirugía Bucal, Universidad de Sevilla
(3) Odontólogo. Práctica privada
(4) Cirujano Oral y Maxilofacial. Médico Adjunto Servicio de Cirugía Oral y Maxilofacial HH.UU.
"Virgen del Rocío" de Sevilla
(5) Cirujano Oral y Maxilofacial. Médico Adjunto Servicio de Cirugía Oral y Maxilofacial HH.UU.
"Virgen del Rocío" de Sevilla. Médico Estomatólogo. Prof. Asociado de Cirugía Bucal, Facultad Odontología de Sevilla
(6) Médico Interno Residente. Servicio de Cirugía Oral y Maxilofacial HH.UU. "Virgen del Rocío" de Sevilla. España

Address:
Dr. Rodolfo Belmonte Caro
Servicio de Cirugía Oral y Maxilofacial. HH.UU. "Virgen del Rocío".
Avda Manuel Siurot s/n.
Sevilla 41013.
Tfno: 955012608. Teléfono personal: 954577836
E-mail: rbelmonte@interbook.net

Received: 24-12-2003. Accepted: 9-05-2004

Belmonte-Caro R, Vélez-Gutiérrez MJ, García De La Vega-Sosa FJ, García-Perla-García A, Infante-Cossío PA, Díaz-Fernández JM, Torres-Carranza E. A Stafne's cavity with unusual location in the mandibular anterior area. Med Oral Patol Oral Cir Bucal 2005;10:173-9.
© Medicina Oral S. L. C.I.F. B 96689336 - ISSN 1698-4447

 

ABSTRACT

The typical Stafne’s cavity, located on the posterior portion of the mandible, is a relatively uncommon entity. However, when the defect is located in the anterior region of the mandible, it is quite rare, having thus far been described in only 36 cases in the scientific literature. Most of these defects appear in the fifth and sixth decades of life, are localized to the area of the canines and premolars, and have a predilection for males. The inferior dental canal, one of the anatomical-radiographic landmarks that aid in the diagnosis of Stafne’s cavity in the posterior region, is rarely present anterior the mental foramen. For this reason, because of its more variable radiographic appearance compared to the posterior defect, its tendency to be superimposed over the apices of the teeth, and the rarity of its localisation to the anterior mandible, it is much more difficult to establish a definitive diagnosis of a Stafne’s cavity in this location. It is therefore more likely that a diagnostic error can occur, especially early on. We present a new case in a 68-year-old male in which the diagnosis was serendipitous, and we review in particular the aetiology and pathogenesis, clinical aspects, and differential diagnoses for this condition.

Key words: Stafne, anterior lingual mandibular salivary gland defect.

RESUMEN

La típica cavidad de Stafne, localizada en el sector posterior de la mandíbula, es una entidad relativamente poco frecuente, pero cuando el defecto se sitúa en la región anterior mandibular, es bastante raro, habiéndose descrito hasta ahora sólo 36 casos en la literatura científica. La mayoría de estos defectos aparecen entre la quinta y la sexta décadas de la vida, están localizados en el área de caninos y premolares, y muestran también una predilección por el sexo masculino. El canal dentario inferior, uno de los hitos anatomo-radiológicos principales que ayudan al diagnóstico de la cavidad de Stafne en la zona posterior, raramente está presente anteriormente al agujero mentoniano. Por ello, por su apariencia radiográfica más variable que en el defecto posterior, por soler encontrarse superpuesta a los ápices de los dientes, y por la rareza de presentación en el sector anterior mandibular, es mucho más difícil establecer un diagnóstico definitivo de cavidad de Stafne en esta localización, y por tanto es más fácil que pueda haber un error en el diagnóstico, sobre todo inicialmente. Presentamos un nuevo caso, en un varón de 68 años, en el que el diagnóstico fue fortuito, y revisamos especialmente sus aspectos etiopatogénicos, clínicos, y de diagnóstico diferencial.

Palabras clave: Stafne, defecto glandular salival mandibular lingual anterior.

 

INTRODUCTION

Since the time of the original study by Stafne in 1942 (1), a wide variety of terms have been used to describe this disease entity, whose common sign is a characteristic well-circumscribed radiolucency in the area of the angle of the mandible below the inferior dental canal. Of these terms, some of the more common are static or latent osseous cavity (or defect), the eponym "Stafne's cavity," and the terms aberrant defect of the salivary gland, and mandibular salivary gland inclusion. Of its denominations, Stafne's cyst is incorrect since it is not a true cyst because it lacks epithelial lining, and the term "cavity" or "defect" is preferred and considered more appropriate (2). In 1957, Richard and Ziskind (3) were the first to describe the occurrence of a Stafne's cavity in the anterior region of the mandible, which was associated with the presence of the sublingual gland. They called this cavity aberrant salivary gland tissue in the mandible. Later, Buchner et al (4) opted to call Stafne's cavity in the anterior region an "anterior lingual mandibular salivary gland defect" (ALMSGD).

To this point, we have only found 36 cases of ALMSGD described in the scientific literature (5,6). The purpose of this paper is to describe a new case and point out its radiographic presentation as a radicular cyst and its peculiarities with respect to diagnosis.

CLINICAL CASE

This case involves a 68-year-old male with no relevant medical history, who was examined in our centre for a left paramandibular radiolucent lesion of 5-6 years duration, which was discovered on routine radiography and referred by his dentist, who had designated it a radicular cyst, with an apparent relationship to apical pathology of the adjacent teeth (teeth 33 and 34). We saw that the lesion was associated with the apices of the teeth, though the latter were slightly separated from the somewhat sclerotic border of the lesion. Since it was asymptomatic and had not changed in size since the initial diagnosis, we decided to examine it annually. Due to the small apical image of the endodontically treated 34 (fig. 1) and a slight growth of the lesion since the last examination, and even though it was still asymptomatic, it was believed to be a radicular cyst, and it was decided to perform cystectomy under local anaesthesia. Using a vestibular approach and elevation of a mucoperiosteal flap, the external mandibular cortex was exposed, and a window was opened in it. The lesion was immediately visible at this time, and it could be observed that it did not appear cystic as initially suspected. Rather, it appeared smooth but firm and reddish-brown, and at this time it was believed that it could be a tumour with a vascular (aneurismal bone cyst, hemangioma, cavernous angioma) or salivary gland component. While dissecting the tumour, we confirmed its salivary gland character, noting that it was continuous with the sublingual salivary gland. Some important perilesional vessels were ligated, and the tumour was pulled outward, being fully exposed (fig. 2), and it was observed that the internal mandibular cortex was lacking in an area of about 2x2cm. Having been completely exposed, the lesion was then clamped at its base and transected, with immediate ligation.

However, immediately following this, in spite of the ligation, severe haemorrhage ensued, which caused a vasovagal reaction in the patient and resulted in a significant haematoma in the floor of the mouth and the neck at the submental level (fig. 3). The haemorrhage was contained by means of compression and plugging with Surgicel® (Ethicon Sarl, Neuchâtel, Switzerland). However, this made it necessary for the patient to be admitted to the hospital for monitoring and observation until the following day. After this episode was resolved, healing occurred without complications, and clinical examination of the patient one year after intervention was satisfactory. Histologic analysis of the excised mass revealed salivary gland tissue. This was therefore a true case of imprinting of the sublingual salivary gland in the internal mandibular cortex, with resorption of the same.

DISCUSSION

Stafne's cavity in the posterior region of the mandible presents with a characteristic localisation and radiographic appearance, facilitating the diagnosis. It typically appears as a unilocular radiolucent rounded or elliptical lesion, which is well demarcated by a line of sclerotic bone and localises between the first lower molar and the angle of the mandible below the inferior dental canal (1). The lingual defect can rarely be palpated, and on occasions sialography of the submandibular salivary gland can be useful in diagnosis as it shows the distribution of contrast in the radiolucent zone, which tends to be occupied by submandibular salivary gland tissue (7). These defects are generally asymptomatic and non-progressive. For this reason, immediate surgical treatment is not indicated. Rather, radiographic monitoring is recommended.

Most cases of ALMSGD localized to the premolar and canine region, always anterior to the first molar, with very few cases affecting the incisors. ALMSGD is considered to be quite rare, in spite of cases that have been published of lesions affecting the molar region associated with the mandibular canal. As with posterior defects, the highest incidence occurs in the fifth and sixth decades of life (60%), with greater than 80% of cases in males (5). They are most commonly unilateral and were usually found serendipitously during routine radiography (intraoral or panoramic, and sometimes computed tomography (CT) or a Dentascan), as they were generally asymptomatic except in a few cases in which the patients presented with mild pain in the region (8). To our knowledge, our case was diagnosed in the oldest patient yet.

Radiographically, ALMSGD have appeared as a unilocular, ovoid or circular, and circumscribed radiolucent image, though in one case it appeared multilocular (9). They have generally localised to below the radicular apices of the teeth or partially superimposed on them, appearing similar to a cystic lesion or an odontogenic tumour. The borders tended to be well defined and slightly sclerotic, though some have been very sclerotic and poorly defined (4,5,8). The size of the lesions has generally varied between 0.5 and 2cm at the greatest diameter, with only one very large defect of 9cm being described (9). These defects have occasionally contacted the adjacent roots, similar to a periapical lesion (10), and endodontic treatments were often performed on these teeth, which failed, thus leading to surgical treatment. En a few cases, the defects localised to an edentulous area, where tooth extraction had been performed previously, and appeared similar to a residual cyst (5).

Three types of Stafne's bone cavities have been described (11), according to the radiographic relationship with the buccal cortex. In type I, the cavity does not reach the buccal cortex. In type II, it reaches it without expanding it. In type III, the buccal osseous cortex is expanded. Another classification in three categories has also been proposed based on the density value of its contents (11): category F indicates fat density, category S soft tissue density, and category G glandular tissue on the inside. Our patient would correspond to type II and category G.

On histopathlogic examination, the vast majority of these defects contained normal or inflamed salivary gland tissue, which probably corresponded to the sublingual salivary gland, since in most cases, such as ours, the cavity was connected to the adjacent salivary gland, resulting in a rather large defect in the mandibular lingual cortex (5). However, in some cases the defect contained adipose or fibrous connective tissue, muscular or vascular tissue, or has even been found to be empty (4,8,12).

The pathogenesis of this lingual osseous defect is not yet fully understood. Two hypotheses are most commonly accepted: A) Stafne (1) and other authors (7,12,13) believed that it could be related to a congenital defect due to entraptment of a portion of the glandular tissue during mandibular development and ossification. Seward (7) believed that the consistency in location, uniformity in appearance, occasional bilateral occurrence, and the small amount of change with time support this hypothesis. The main objection to this theory, based on cases with previous normal radiographs, is that the defect is much more common in adults than in children, which suggests that it develops later in life, after ossification of the mandible (14). On the other hand, the theory is supported by the fact that there are cases in which the defects have been seen to develop slowly. B) Another hypothesis is that the osseous defect develops more slowly as a result of locally exerted chronic pressure from the submandibular gland in posterior defects and from the sublingual gland in anterior defects (13), which would result in erosion and resorption. This would be based on the delayed radiographic appearance and the detection of the defect in middle-aged individuals. Some authors believe that a compensatory glandular hypertrophy would occur as a result of lymphocytic infiltration and reduced secretory efficiency, which both increase with age. Others believe glandular growth would occur as a part of general somatic growth (8,14).

Unlike the posterior defect, ALMSGD is more difficult to diagnose, especially because of its much more variable radiographic appearance and because the inferior dental canal is not present in this portion of the mandible. This makes it easier to confuse this lesion with other unilocular radiolucent lesions, particularly those with cystic pathology.

When ALMSGD is suspected, additional examinations should be done to confirm the diagnosis, which can only be definitively confirmed histologically. Sialography is not normally recommended since it provides little information on the sublingual gland (8). CT (11) or magnetic resonance imaging (MRI) are preferred since axial radiographic sections can aid in diagnosis and planning of a surgical approach (9). The Dentascan CT, which is easy to perform, is suggested as the most appropriate non-invasive diagnostic and monitoring modality, especially when image reconstruction is performed (10). MRI does not expose the patient to ionising radiation and avoids the use of contrast material and the discomfort of sialography. However, it is more expensive and artefacts result from the presence of metals (2).

The most important differential diagnoses that we can consider (4,8,10,15) include radicular cyst, residual cyst, non-inflammatory odontogenic cyst, lateral periodontal cyst, and odontogenic keratocyst. Additionally, many other lesions should not be forgotten such as ameloblastoma and other odontogenic tumours, some benign tumours, and even osseous metastasis. ALMSGD should also be differentiated from labial osseous concavities, which are usually present in the anterior region of the maxilla, are characterised by thinning of the bone, appear more radiolucent, and are easily palpable.

Once a suspected diagnosis is established, surgical treatment is not necessary for Stafne's cavity. Rather, radiographic monitoring is indicated for both the posterior and the anterior forms. Surgical exploration and biopsy should only be performed when the diagnosis is uncertain or in exceptional cases when an unusually severe pathology is suspected. Initial diagnostic confusion can result in unnecessary treatment such as endodontic treatment, osseous trephination, and osseous exploration (10). If treated surgically, it is recommended to make the approach to the lesion by elevating a lingual mucoperiosteal flap, which provides better access to the region, reduces surgical trauma, and often avoids unnecessary manipulating of the vestibular cortex. In order to re-establish the osseous defect, some authors suggest using guided osseous regeneration techniques (8). In our patient, postoperative radiographic follow up at one year revealed less radiolucency at the level of the lesion, which we believe is due to newly-formed bone. However, because the patient declined further surgical intervention, we do not have histologic evidence of this.

Our case presented serendipitously. It was initially believed to be a case of a radicular cyst, so further radiographic examination was not performed preoperatively (particularly CT sections) to show the mandibular lingual cortical defect. Because adequate access to the lesion was possible through the vestibular approach, as has been described in other cases (5), and because we did not have a definitive diagnosis of glandular tissue involvement, we did not perform a mandibular lingual approach, which would have offered a better visual field and control of the process. It is important to emphasise, as other authors have (6), the need to obtain a thorough history and clinical examination of the patient in cases of mandibular radiolucencies. Furthermore, when such a lesion is suspected, appropriate complementary testing should be performed, since the approach to this lesion can carry a significant risk if sufficient caution is not exercised. This was the situation in our case in which profuse haemorrhage occurred, though it was subsequently controlled without extending the initial surgical incision.

Although ALMSGD are rare in the literature, we believe, as do other authors (8), that this condition is probably much more common in part because many of these lesions are merely normal anatomic variants and are only observed radiographically when the defect is extensive. Moreover, since this lesion is not generally considered, many would make a chance diagnosis upon examination of the patient or even during surgery, as has occurred in some published cases (5), and would not publish the finding due to a lack of the necessary documentation because of the unexpected presentation.

REFERENCES

1. Stafne EC. Bone cavities situated near the angle of the mandible. J Am Dent Assoc 1942;29:1969-72.        [ Links ]

2. Branstetter BF, Weissman JL, Sheldon BK. Imaging of a Stafne bone cavity: what MR adds and why a new name is needed. Am J Neuroradiol 1999; 20:587-9.        [ Links ]

3. Richard EL, Ziskind J. Aberrant salivary gland tissue in mandible. Oral Surg Oral Med Oral Pathol 1957;10:1086-90.        [ Links ]

4. Buchner A, Carpenter WM, Merrell PW, Leider AS. Anterior lingual mandibular salivary gland defect. Evaluation of twenty-four cases. Oral Surg Oral Med Oral Patol 1991;71:131-6.        [ Links ]

5. de Courten A, Kuffer R, Samson J, Lombardi T. Anterior lingual mandibular salivary gland defect (Stafne defect) presenting as a residual cyst. Oral Surg Oral Med Oral Patol Oral Radiol Endod 2002;94:460-4.        [ Links ]

6. Dorman M, Pierse D. Ectopic salivary gland tissue in the anterior mandible: a case report. Br Dent J 2002;193:571-2.        [ Links ]

7. Seward GR. Salivary gland inclusions in the mandible. Br Dent J 1960; 108:321-5.        [ Links ]

8. Apruzzese D, Longoni S. Stafne cyst in an anterior location. J Oral Maxillofac Surg 1999; 57:333–8.        [ Links ]

9. Hayashi Y, Kimura Y, Nagumo M. Anterior lingual mandibular bone concavity. Report of a case. Oral Surg Oral Med Oral Pathol 1984;57:139-42.        [ Links ]

10. Katz J, Chaushu G, Rotstein I. Stafne’s bone cavity in the anterior mandible: a possible diagnostic challenge. J Endod 2001;27:304-7.        [ Links ]

11. Ariji E, Fujiwara N, Tabata O, Nakayama E, Kanda S, Shiratsuchi Y, et al. Classification based on outline and content determined by computed tomography. Oral Surg Oral Med Oral Pathol 1993;76:375-80.        [ Links ]

12. Salman L, Leffler M, Reddi T, Yamane G, Chaudry A. Stafne’s bone (defect) simulating dentigerous cyst of the mandible. J Oral Med 1986;41:239-41.        [ Links ]

13. D’Eramo EM, Poidmore JS. Developmental submandibular gland defect of the mandible. Review of the literature and report of a case. Oral Surg Oral Med Oral Pathol 1975;39:14-9.        [ Links ]

14. Sandy JR, Williams DM. Anterior salivary gland inclusion in the mandible: pathological entity or anatomical variant ?. Br J Oral Maxillofac Surg 1981; 19:223-9.        [ Links ]

15. Wood NK, Goaz PW. Solitary cystlike radiolucencies not necessarily contacting teeth. In: Wood NK, Goaz PW, eds. Differential diagnosis of oral and maxillofacial lesions. 5th ed. St. Louis: Mosby-Year Book, Inc; 1997. p. 318.        [ Links ]

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons