Genotoxicity of digital panoramic radiography on oral epithelial tissues.

OBJECTIVE: To evaluate the genotoxic effects of x-rays on gingival and buccal epithelial cells during panoramic dental radiography using the micronucleus test. METHOD AND MATERIALS: Eighty otherwise healthy subjects who required a diagnostic panoramic radiograph and met the selection criteria were included in the study. Epithelial cells were obtained from the maxillary anterior gingiva and buccal mucosa by gentle scraping with a wooden spatula immediately before exposure and again 10 days after exposure. Cytologic preparations were made according to the Papanicolaou staining method and analyzed under a light microscope for micronucleus count. RESULTS: The mean ± SD micronucleus count of gingival epithelial cells was 1.08 ± 0.76 before radiographic exposure and 1.6 ± 0.93 after exposure. This increase was statistically significant (P < .05). Similarly, there was an increase in the postexposure micronucleus count in the buccal mucosa, but this increase was not significant (P > .05). A significant correlation was observed between the age of subjects and micronucleus count, although no such correlation was found between sex and micronucleus count. CONCLUSION: Although radiation-related effects from panoramic radiography were reduced compared with full-mouth intraoral periapical radiographs or radiotherapy, the results of this study show that genotoxic effects do take place. Thus, radiographs should be taken with adequate protection measures and only when the potential benefit outweighs the potential risk.

Elastography: the next step.

In the past few decades, various tools have emerged that claim to enhance detection of oral cancer. The most important prognostic factor in patients with oral cancer is lymph node status: the presence of nodal spread decreases the 5-year survival rate by approximately 50%. Differentiation between reactive and metastatic lymphadenopathy is thus vital, and one differentiating criterion is hardness (elasticity) of the lymph node. The purpose of this review is to highlight a promising new ultrasound technique, known as elastography, which measures the characteristics of tissue compliance. The principles underlying elastography are that tissue compression produces strain (displacement) within the tissue - which is lower in harder tissues than in softer tissues - and that malignant tissues are generally harder than normal surrounding tissue. Therefore, elastography might yield clinical information useful in diagnosing cervical metastasis and improving prognosis in oral cancer. It has long been used for cancers of the breast, pancreas, and thyroid, and its use in cervical lymphadenopathy is now being explored, which could lead to great advancements in the diagnosis and prognosis of oral cancer.

Situs inversus in a patient with nevoid basal cell carcinoma syndrome: a histogenetic relationship?

Nevoid basal cell carcinoma syndrome (NBCCS) is an uncommon autosomal dominant inherited disorder with high penetrance and variable expressivity. It affects multiple organ systems, including the stomatological, skeletal, skin, eye, reproductive, and central nervous systems. It is caused by mutations in the patched tumor suppressor gene, PTCHI, located in the 9q22.3-q31 chromosome. To our knowledge, this is the first report of a patient with unusual radiological features, i. e. dextrocardia and situs inversus totalis, in conjunction with common features including multiple keratocystic odontogenic tumors, bifid ribs, palmar and plantar pits, bridging of the sella turcica and calcification of the falx cerebri. We examined whether these genetic conditions were associated, as both involve ciliary dysfunction.