Assessment of prevalence and volumetric estimation of possible Stafne bone concavities on cone beam computed tomography images

Surgical Exploration of Lingual Mandibular Bone Depression (Stafne Bone Cavity)

Lingual mandibular bone depression, also known as the Stafne bone cavity, commonly presents as an asymptomatic unilocular cyst-like radiolucency located below the mandibular canal. Surgical exploration of this lesion is relatively rare in the literature. A 49-year-old male was admitted to the hospital for a space-occupying lesion located in the right mandibular angle region and was performed surgical exploration. The content of the lesion was excised and prepared for histologic investigation, which revealed fibrous connective tissue, adhering muscle and nervous tissue with no evidence of epithelium tissue. Thus, the lesion was diagnosed as lingual mandibular bone depression. Of the various theories of the etiology of lingual mandibular bone depression, the most popular "glandular theory" seemed to be inapplicable in the present case. Providing misleading information in this case, B-mode ultrasonography was proved to be of little help in diagnosing this lesion.

[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.

Atypical variant of Stafne bone defect mimicking odontogenic cyst of the jaw

Stafne first described the term "Stafne bone defects" (SBDs) in 1942. These are unilateral, asymptomatic, well-defined radiolucent lingual bony defects located at the posterior region of the mandible below the inferior alveolar canal. It is most commonly seen in the posterior region, whereas it is relatively rare in the anterior region. This anterior variant of SBD is often misdiagnosed as any other odontogenic cyst, and hence advanced imaging techniques should be followed to identify it at the earliest. Due to the lower prevalence of this entity, only a handful of cases have been documented for the anterior variant of SBD. In this paper, we have thus documented the rare variant of SBD in the anterior region.

The prevalence of Stafne bone cavity: A meta-analysis of 355,890 individuals

Background/purpose

A Stafne bone cavity (SBC) is an incidental depression in the lingual surface of the mandible. The aim of this study is to provide pooled estimates of the frequency of Stafne bone cavity and to correlate its presence with such variables as sex, laterality, diagnostic methods and population.

Materials and methods

Potential studies were searched through four electronic databases: Google Scholar, PubMed, Scopus, and Journal Storage. Titles, abstracts, and full texts of the articles were screened.

Results

A total of 54 studies relating to 355,890 subjects met the inclusion criteria for meta-analysis. A meta-analysis using the DerSimonian-Laird model revealed an overall prevalence of 0.17% (CI:0.14%-0.21%, I ² = 80.7%). SBC was four times more common in males than females (z = 6.94, P < 0.01), and was unilateral in almost all cases (z = 12.90, P < 0.01). Radiographic studies yielded a lower SBC prevalence at 0.12% (CI:0.09%-0.15%, I ² = 71.7%) than computed tomography studies, skeletal studies and excavation studies. Ancient populations had three times higher SBC prevalences (0.47%, CI:0.21%-0.73%, I ² = 89.5%) than the average populations today (z = 3.21, P < 0.01).

Conclusion

The prevalence of Stafne bone cavity is approximately 0.17%, and was four times more prevalent in males than females. This variant bone cavity was also present unilaterally in the majority of cases. Awareness of SBC is important for dentists, maxillofacial surgeons and other practitioners performing routine dental practices and interpreting panoramic radiographs.

Is it possible to estimate volume of bone defects formed on dry sheep mandibles more practically by secondarily reconstructing section thickness of cone beam computed tomography images?

OBJECTIVES

The purpose of this study was to evaluate the effect of section thickness on volume estimations of bone defects scanned using cone beam computed tomography (CBCT).

METHODS

25 bone defects were prepared on sheep mandibles and scanned using a KaVo 3D eXam (KaVo Dental, Biberach, Germany) CBCT device. Section thickness of images were reconstructed at 0.25, 0.5, and 0.75 mm to estimate the volume of these defects using the semiautomatic segmentation method. The volume averages obtained using microcomputed tomography and Archimedes' method served as reference values. The estimated volumes at each section thickness were compared with the actual volumes using the Friedman test. The accuracy of volume estimation was determined by the percentage error with respect to the reference values, and the mean absolute error (MAE) was calculated.

RESULTS

Volumetric values of bone defects obtained with CBCT at section thicknesses up to 0.5 mm were compatible with the actual volumes (p > 0.05). The percentage errors at section thicknesses of 0.25, 0.5, and 0.75 mm were -5.4%, -7.3%, and -13.1%, respectively. The mean absolute errors were 13.6 mm³, 15.7 mm³, and 18.2 mm³, respectively.

CONCLUSIONS

The section thickness values of CBCT images can be increased to a reasonable level to obtain accurate volume estimation results and save time. The semiautomatic segmentation method can be used reliably for volume estimations of bone defects.