Stafne bone defects radiographic features in panoramic radiographs: Assessment of 91 cases

Radiological features of Stafne mandibular bone cavity in panoramic image and cone beam computed tomography

BACKGROUND

Stafne mandibular bone cavity (SMBC) is an asymptomatic radiolucent lesion observed in the mandible on X-ray images, with well-defined borders. This lesion does not require treatment, and size changes are very rare. The purpose of this article is to summarize the radiological and clinical features of SMBC, aiming to prevent misinterpretation of this benign lesion as other pathologies and aid in differential diagnosis within the field of dental practice.

METHODS

A total of 32 patients who visited our hospital and were radiologically diagnosed with SMBC based on cone-beam computed tomography (CBCT) and panoramic images between 2005 and 2021 were included in this study. Among them, surgical intervention was performed in one case. Gender and age distribution of the patients, radiographic location and size of the lesion, relationship with the mandibular canal in CBCT, presence of cortical bone erosion in the mandibular lingual area in panoramic images, and the amount of residual cortical bone on the affected side in CBCT were investigated.

RESULT

Patients were 26 men (81.3%) and 6 women, with a mean age of 54.3 years. The average horizontal and vertical length was 16.6 mm and 10.6 mm. Out of a total of 32 cases, 29 cases were found in the posterior region of the mandibular body, while 3 cases were in the angle of the mandible. Lesions located below the mandibular canal were observed in 29 cases, while lesions involving the mandibular canal were present in 3 cases. Erosion of the mandibular lingual cortical bone was observed in 11 cases (34.4%), while 21 cases (65.6%) showed no erosion on panoramic images. Among the total of 14 cases (43.8%) where the cortical bone on the affected side was invaded, the average residual cortical bone thickness was 1.1 mm.

CONCLUSION

SMBC is a benign lesion primarily found in the mandibular angle and posterior body of the mandible. In most cases, treatment is not necessary, and differentiation from other lesions can be achieved by understanding its clinical characteristics and features on panoramic radiographs and CBCT.

Stafne's Bone Defect Correlated with Submandibular Glands: A Case Report and CBCT and MRI Analysis

Stafne's bone defect is a developmental anatomic bone defect in the lingual side of the mandible in the area of the mandibular angle that is filled with proliferation or translocation of adjacent structures such as salivary gland tissue. The etiology is still undefined, and two hypotheses are proposed: one is the glandular related to the submandibular or sublingual glands and the second is ischemic that affects the vascularization of the mandibular lingual. Usually, Stafne's bone defect is accidentally detected on panoramic radiographs during dental treatments as a well-limited radiolucency image with a clear peripheral regular condensation border, located below the mandibular canal. The differential diagnosis includes traumatic bone cyst, odontogenic and nonodontogenic cystic lesions, nonossifying fibroma, focal osteoporotic bone marrow defect, and other lesions. A case of Stafne's bone defect on a 60-year-old male patient extending in the lingual posterior part of the mandibular region was presented. The panoramic radiograph revealed a well-limited radiolucency image with a clear peripheral regular condensation border, located below the mandibular canal. The lesion was discovered in a routine radiographic exam: the cone beam computed tomography gave us more details about the localization, the shape and size, and the relation with the mandibular canal, and the magnetic resonance imaging identifies the nature of the inside soft tissue. The final diagnosis was a Stafne's bone defect resulting of a depression of the lingual cortical plate filled with expansion of the submandibular gland.

[Stafne's bone cavity in a venezuelan population. Prevalence study]

Objective

To determine the prevalence of the Stafne´s bone cavity in a Venezuelan population and to characterize it radiographically.

Method

Descriptive and cross-sectional study. Of 500 panoramic radiographs, those that had radiolucent images in the mandible, circumscribed and not associated with any dental organ, as well as those that could correspond to the mandibular fossa, were selected. Results were collated and discrepancies resolved by consensus. The selected ones were characterized radiographically. The variables were compared using the student's t test for equality of means, applying the Levene test, values of p <0.05 were considered statistically significant.

Results

Of the 500 radiographs evaluated, 22 presented images corresponding to deep mandibular fossa or Stafne bone cavities, which represented 4.4%. Of which 5 presented bilaterally (22.7%) and 17 (77, 3%) unilocularly. Among the radiographic characteristics studied, images located in the posterior area (81.81%), without sclerosis (54.54%), continuous to the basal mandibular area, round shape (59.09%) and partial radiolucency (72%) were presented with a higher prevalence). They were more common in male patients with 63.63%.

Conclusions

Our results show a higher prevalence of Stafne's bone cavity in a Venezuelan population than that reported in other studies in other populations.

[Stafne defect as a rare anomaly of the lower jaw growth]

Defects in mandible growth are of undoubted interest for practical healthcare. During the diagnosis, for a more accurate diagnosis and differential diagnosis, it is necessary to understand the criteria for the norm and pathology of diseases of the jaw bones. Often in the body of the mandible at the level of the lower molars, slightly below the maxillofacial line, defects are detected in the form of a depression of the cortical layer towards the unchanged buccal cortical plate. These defects, being the clinical norm, need to be differentiated with many tumor diseases of the maxillofacial region. The literature sources indicate that the cause of these defects is the pressure of the capsule of the submandibular salivary gland in the area of the fossa on the lower jaw. Modern additional diagnostic methods, for example, CBCT and MRI, make it possible to identify a Stafne defect.

[Stafne's idiopathic bone cavity: characteristics and imagenological considerations. A review]

In 1942, Dr. Edward Stafne presented 35 cases of asymptomatic, clearly defined, round or ovoid radiolucencies occurring near the angle of the mandible, with a greater incidence below the lower dental canal, between the mandibular angle and the roots of the first lower molar, which he referred to as a bone defect. This bone defect later became known by other names.Clinically, Stafne's idiopathic bone cavity (SIBC) is asymptomatic, is usually not palpated intraorally and has no present extraoral signs. Thus, in most cases it is an accidental radiological finding, which appears as a delimited, elliptical or rounded radiolucent image, with a diameter ranging from 1 to 3 cm, and delimited by osteocondensation in the anteroinferior limits. According to the location of the findings, they are classified as; anterior, posterior and branch.This entity should be considered as a variant of normality requiring differential diagnosis to achieve an accurate diagnosis. The present review provides information on the history, and general and radiographic characteristics of SIBC to facilitate diagnosis when presented with this type of findings.

Lingual Mandibular Bone Depression

BACKGROUND/AIM

In the area of the jaw angle, osteolytic lesions can occur, the differential diagnosis of which can be difficult and require very different therapeutic measures. One of these lesions is lingual mandibular bone depression (LMBD). The aim of this study was to present the characteristics of the lesion in a group of LMBD patients and to differentiate it from other lesions.

PATIENTS AND METHODS

Radiological images of 21 patients with LMBD were examined.

RESULTS

The majority of LMBDs were located in the jaw angle. On cross-sectional images, the lesion could be distinguished from salivary tissue (n=2). One case of LMBD had an impact on the course of the fracture line in the mandibular trauma.

CONCLUSION

LMBD is a developmental disorder of the mandible and only rarely of pathological importance. Imaging the lesion with cross-sectional images is preferable to using plain X-ray projections. In some cases, surgical exploration is essential for diagnosis.

Imaging features of Stafne bone defects on computed tomography: An assessment of 40 cases

Purpose

This study was performed to assess and describe the imaging features of 40 cases of Stafne bone defects (SBDs) on computed tomographic (CT) examinations.

Materials and Methods

This study collected data, including age and sex, from 40 patients with SBDs who underwent CT exams. The imaging features of the SBDs were assessed in terms of their location, average size, the relationship of their contour with the cortical plate of the lingual mandible, bone margins, degree of internal density, shape, topographic relationship between the defect and the mandibular edge, the distance from the SBD to the base of the mandible, and the Ariji classification (type I, II, and III).

Results

The average age was 57.3 years (range, 28–78 years), and the patients were predominantly male (70%). In all cases (100%), the posterior unilateral lingual SBD variant was observed. Within the Ariji classification, type I was the most common (60%). Among the most frequently observed radiographic characteristics were thick sclerotic bone margin across the entire defect contour, completely hypointense internal content, an oval shape, and continuity with the mandibular base with discontinuity of the mandibular edge.

Conclusion

This study showed that posterior SBDs could present with an oval or rounded shape, complete hypodensity, and thick sclerotic margins. Likewise, SBDs could appear almost anywhere, with minor differences from the classic SBD appearance. It is fundamental for dental practitioners to know the imaging features of SBDs, since they are diagnosed primarily based on imaging.

Stafne's bone cyst revisited and renamed: the benign mandibular concavity

OBJECTIVE

Stafne's bone cyst (SBC) is an asymptomatic, round or oval-shaped, well-defined, uniform radiolucent lesion, usually incidentally observed in the posterior aspects of the mandible. Radiographical appearance may be confusing though. This study aimed to review the literature on SBCs and to map the SBC as shown in their respective papers.

METHODS

A Pubmed® search (1/9/2018 till 31/5/2019), mentioning SBC, was carried out. Included papers had to contain: patient's age, gender and radiographs.

RESULTS

In total, 114 papers were found, but only 64 papers were retained, which contained 109 cases (95 males, 14 females). The patients' ages ranged between 14 and 89 years old (mean age being 52 years). Male patients' ages (N = 95) ranged from 14 to 89 years (mean age 52.3 years), whereas the females (N = 14) ages ranged between 22 and 68 (mean age 50.2 years). 28 combinations of locations of SBC were recorded. Only three lesions were located at the symphysis, six were bilateral, 55 appeared on the left hand side and 45 on the right hand side of the mandible.The literature mentioned that these cavities could contain salivary gland tissue, muscular tissue, lymphoid tissue, blood vessels, fat tissue or connective tissue.

DISCUSSION/CONCLUSION

This study illustrates the wide variation of SBC locations across the mandible and leads us to conclude that the differential diagnosis of every asymptomatic, oval or round, well-defined, uniform radiolucent lesion on two-dimensional radiographs of the mandible should include "a benign mandibular concavity", formerly known as SBC.

Stafne bone cavity: a rare cadaveric case report

The Stafne bone cavity (SBC), also called the static bone cavity, salivary inclusion cyst, latent cyst, and lingual bone defect is an asymptomatic bony defect that is commonly located inferior to the mandibular canal and slightly above the inferior border of the mandible. It is rare to see the actual bony defect in the cadaver because of its relatively low incidence of 0.1% to 6.06%. We report a unilateral SBC found in a 76-year-old at death male Caucasian cadaver and involving the right mandible. The SBC was oval in shape with a smooth surface and measured 10.8×6.0 mm. The SBC was continuous with the right mylohyoid groove. Since actual photographs of the SBC are lacking in the literature, this report might provide additional insight for better understanding the SBC.

Diagnosis and management of Stafne bone cavity with emphasis on unusual contents and location

Stafne bone cavity (SBC) is a rare mandibular defect, and the diagnosis and management may be confused with the unusual contents and location. This report for the first time presented a case of SBC with a lymph node content. Meanwhile, a rare case of anterior SBC with fatty tissue content is reported. Typical SBCs with salivary glands content are asymptomatic and showed a well-shaped, ovoid, radiolucent image in the posterior mandible below the inferior alveolar canal in panoramic radiograph. The case of SBC with a lymph node content underwent surgical operation, and definite diagnosis is confirmed by histopathological examination. The case of anterior SBC with fatty tissue content is clarified by MRI confirmed the presence of the fatty tissue and avoided surgical exploration. Surgical interventions would be an unnecessary option in the management of SBC except for the doubtful cases or concomitant other pathologies.

Unusual Conditions Impairing Saliva Secretion: Developmental Anomalies of Salivary Glands

Salivary glands (SG) arise from ectodermal tissue between 6 and 12th weeks of intrauterine life through finely regulated epithelial-mesenchymal interactions. For this reason, different types of structural congenital anomalies, ranging from asymptomatic anatomical variants to alterations associated with syndromic conditions, have been described. Notable glandular parenchyma anomalies are the SG aplasia and the ectopic SG tissue. Major SG aplasia is a developmental anomaly, leading to variable degrees of xerostomia, and oral dryness. Ectopic SG tissue can occur as accessory gland tissue, salivary tissue associated with branchial cleft anomalies, or true heterotopic SG tissue. Among salivary ducts anomalies, congenital atresia is a rare developmental anomaly due to duct canalization failure in oral cavity, lead to salivary retention posterior to the imperforate orifice. Accessory ducts originate from the invagination of the developing duct in two places or from the premature ventral branching of the main duct. Heterotopic ducts may arise from glandular bud positioned in an anomalous site lateral to the stomodeum or from the failure of the intraoral groove development, hindering their proximal canalization. These anomalies require multidisciplinary approach to diagnosis and treatment. While ectopic or accessory SG tissue/ducts often do not require any treatment, patients with SG aplasia could benefit from strategies for restoring SG function. This article attempts to review the literature on SG parenchyma and ducts anomalies in head and neck region providing clinicians with a comprehensive range of clinical phenotypes and possible future applications of bioengineered therapies for next-generation of regenerative medicine.