Influence of Vitamin D Deficiency on Cyclin D1-Induced Parathyroid Tumorigenesis.

Primary hyperparathyroidism (PHPT) is a common endocrinopathy for which several pathogenic mechanisms, including cyclin D1 overexpression, have been identified. Vitamin D nutritional status may influence parathyroid tumorigenesis, but evidence remains circumstantial. To assess the potential influence of vitamin D insufficiency/deficiency on initiation or progression of parathyroid tumorigenesis, we superimposed vitamin D insufficiency or deficiency on parathyroid tumor-prone parathyroid hormone-cyclin D1 transgenic mice. Mice were placed on diets containing either 2.75 IU/g, 0.25 IU/g, or 0.05 IU/g cholecalciferol, either prior to expected onset of PHPT or after onset of biochemical PHPT. When introduced early, superimposed vitamin D insufficiency/deficiency had no effect on serum calcium or on parathyroid gland growth. However, when introduced after the onset of biochemical PHPT, vitamin D deficiency led to larger parathyroid glands without differences in serum biochemical parameters. Our results suggest that low vitamin D status enhances proliferation of parathyroid cells whose growth is already being tumorigenically driven, in contrast to its apparent lack of direct proliferation-initiating action on normally growing parathyroid cells in this model. These results are consistent with the hypothesis that suboptimal vitamin D status may not increase incidence of de novo parathyroid tumorigenesis but may accelerate growth of a preexisting parathyroid tumor.

Patient shielding during dentomaxillofacial radiography: Recommendations from the American Academy of Oral and Maxillofacial Radiology.

BACKGROUND: The American Academy of Oral and Maxillofacial Radiology established an ad hoc committee to draft evidence-based recommendations and clinical guidance for the application of patient contact shielding during dentomaxillofacial imaging. TYPES OF STUDIES REVIEWED: The committee reviewed monographs and reports from radiation protection organizations and studies that reported radiation dose to gonads, breasts, and thyroid gland from dentomaxillofacial imaging. RESULTS: Considering the absence of radiation-induced heritable effects in humans and the negligible dose to the gonads and fetus from dentomaxillofacial imaging, the committee recommends discontinuing shielding of the gonads, pelvic structures, and fetuses during all dentomaxillofacial radiographic imaging procedures. On the basis of radiation doses from contemporaneous maxillofacial imaging, the committee considered that the risks from thyroid cancer are negligible and recommends that thyroid shielding not be used during intraoral, panoramic, cephalometric, and cone-beam computed tomographic imaging. PRACTICAL IMPLICATIONS: This position statement informs and educates the reader on evolving radiation protection practices and provides simple, unequivocal guidance to dental personnel to implement these guidelines. State and local authorities should be contacted to update regulations to reflect these recommendations.

MR appearance of a rare ameloblastic fibroma with formation of dental hard tissues with histopathologic correlation: a case report.

An ameloblastic fibroma with formation of dental hard tissues, which the classical name is ameloblastic fibro-odontoma (AFO), is a rare type of mixed odontogenic tumor. An 8-year-old boy was diagnosed with AFO, with an inhomogeneous high signal within the lesion shown by T2-weighted magnetic resonance imaging (MRI). Computed tomography (CT) imaging revealed a unilocular low CT value area of 24 × 19 × 26 mm with buccolingual bony expansion and cortical bone thinning on the left side of the mandible including the crown of the mandibular left second molar. In addition, multiple calcified bodies were detected within the lesion, one of which had a CT value of approximately 2200 HU, equivalent to that of enamel. MRI indicated the lesion to be sized 24 × 19 × 25 mm along with buccolingual bony expansion in the left side of the mandible. Additionally, the lesion showed an internal inhomogeneous high signal, while a portion had an especially high signal in T2-weighted images. That particularly high signal area coincided with the nodular growth area of mucus-rich mesenchymal components without the epithelial component in histopathology findings. The particularly high signal revealed by T2-weighted imaging could be attributed to the mucus-rich component. MRI was found useful for revealing differences in the internal histopathological properties of an AFO in our patient.

Radiation-induced undifferentiated spindle cell sarcoma following high-dose-rate interstitial brachytherapy for tongue squamous cell carcinoma.

High-dose-rate interstitial brachytherapy (HDR-ISBT) has recently come to be considered one of the most effective treatments for oral cancer. On the other hand, it is important to note that radiation therapy has some side effects. Especially, radiation-induced malignancy is probably the most serious complication affecting long-term survivors. We report a case of a radiation-induced undifferentiated spindle cell sarcoma that developed following HDR-ISBT for tongue squamous cell carcinoma (SCC). A 39-year-old woman with right tongue SCC underwent HDR-ISBT (60 Gy, 10 fractions, 8 days) treatment. Five years and one month later, a tumor had developed at the primary site. Surgery was performed for the tumor, which was histopathologically diagnosed as an undifferentiated spindle cell sarcoma. That was distinct from the squamous cell origin of the primary cancer. According to recently established criteria for radiation-induced malignancy, this case was classified as a radiation-induced sarcoma. A search of the literature revealed no previous report of radiation-induced malignancy following HDR-ISBT for tongue cancer.

Recommendations for imaging of the temporomandibular joint. Position statement from the American Academy of Oral and Maxillofacial Radiology and the American Academy of Orofacial Pain.

This position statement was developed by an ad hoc committee of the American Academy of Oral and Maxillofacial Radiology and the American Academy of Orofacial Pain. The committee reviewed pertinent literature and drafted recommendations for imaging. The statement provides evidence-based recommendations and clinical guidance to apply appropriate diagnostic imaging to evaluate the temporomandibular joint.

Clinical evaluation of Er,Cr:YSGG laser therapy used as an adjunct to non-surgical treatment of periodontitis: Twelve-month results from a pilot study.

BACKGROUND: The purpose of this study was to evaluate the results of adjunctive Er,Cr:YSGG laser therapy with scaling and root planing (SRP) as compared with SRP alone in the treatment of moderate to severe periodontitis. METHODS: Fifteen adults (aged 27 to 65 years) with 90 nonadjacent sites probing ≥ 5 mm were treated in split-mouth design with SRP and laser therapy versus SRP alone. Probing pocket depth (PPD), gingival recession (GR), clinical attachment level (CAL), plaque, and bleeding on probing were collected at baseline, 1, 3, 6, 9, and 12 months. Patient reported outcomes were measured to assess pain, sensitivity, and satisfaction. RESULTS: Clinical improvements were similar for test and control sites with no statistically significant difference. At 12 months, the average PPD reduced from 6.1 to 4.2 mm for test and 6.2 to 4.3 mm for control sites. GR increased by 0.4 mm at test and control sites. CAL increased from 6.8 to 5.3 mm for test and 6.9 to 5.5 mm for control sites. Clinical outcomes were stratified by baseline PPD ( = 5, = 6 and ≥7 mm) and analyzed for number of sites that reduced (≤4 mm). No significant difference was observed when the baseline PPD was 5 or 6 mm. Test sites with baseline PPD ≥7 mm demonstrated a statistically significant difference in the percentage of reduced sites when compared with controls at nine (P = 0.001) and 12 months (P = 0.044). CONCLUSIONS: Adjunctive Er,Cr:YSGG laser therapy with SRP provides similar clinical improvement in the treatment of moderate-severe periodontitis as SRP alone and may offer some advantage for deeper (≥7 mm) pockets.

Prognostic factors for lymph node metastasis from upper gingival carcinomas.

OBJECTIVES: This study sought to identify tumor characteristics that associate with regional lymph node metastases in squamous cell carcinomas originating in the upper gingiva. MATERIALS AND METHODS: Data from 113 patients from Osaka University Dental Hospital were included. We measured each primary tumor's width, length, depth, and the extent of bone invasion. Additionally, tumor signal intensity for T1 and T2-weighted images as well as the center of the tumor's location and T classification was assessed, and a histopathological analysis was performed. RESULTS: Tumor signal intensity was not found to be a significant prognostic factor. However, bucco-lingual width, histopathological classification as well as the tumor's location were significantly different between metastatic and non-metastatic groups in both univariate and multivariate analysis. Superior-inferior depth and T classification were significant only in the univariate (and not the multivariate) analysis. CONCLUSIONS: Bucco-lingual width, histopathological grading as well as the tumor's location are likely to be important predictors for the occurrence of LN metastasis in upper gingival carcinoma patients and should be considered when managing care for these patients.

Diffusion-weighted magnetic resonance imaging of the oral and maxillofacial region: optimal fat suppression method.

OBJECTIVE: To compare 3 fat suppression methods-water excitation (WE), chemical shift selective (CHESS), and short T1 inversion recovery (STIR)-for optimal image quality and apparent diffusion coefficient (ADC) values with magnetic resonance imaging (MRI) using diffusion-weighted imaging (DWI) of the oral and maxillofacial region. STUDY DESIGN: In total, 53 patients with 73 lesions were enrolled in this study. MRI using DWI protocols with the 3 fat suppression methods were performed in addition to a conventional MRI protocol. The diagnostic image quality of lesions, image uniformity, degree of image artifacts, and ADC values of the lesions were evaluated. Average visual scores and ADC values were compared, and post hoc pairwise comparisons were performed, with the level of significance set at P < .0167. RESULTS: Diagnostic image quality was not significantly different among the fat suppression methods (P ≥ .042). Image uniformity was significantly higher (P < .001), and the degree of image artifacts was significantly lower (P < .001), in images using the STIR method. Mean ADC values did not differ significantly among the 3 methods. CONCLUSIONS: The STIR method was the most useful fat suppression method for DWI of the oral and maxillofacial region because of its high level of image uniformity and few image artifacts.

Radiographic predictors of bone exposure in patients with stage 0 medication-related osteonecrosis of the jaws.

OBJECTIVE: The aim of this study was to explore the radiographic appearance of stage 0 medication-related osteonecrosis of the jaws (MRONJ) and examine 5 radiographic parameters (trabecular sclerosis, cortical erosion, periosteal reaction, sequestration, and crater-like defect) as predictors of progression to bone exposure. STUDY DESIGN: Twenty-three patients with a history of antiresorptive therapy, no bone exposure, and nonspecific signs and symptoms were included. Intraoral photographs, panoramic and cone beam computed tomography (CBCT) images at initial visit, and follow-up intraoral photographs were reviewed. Three patients had dental disease (DD), 10 patients with stage 0 MRONJ did not progress to bone exposure (NBE), and 10 patients progressed to bone exposure (BE). Radiographic parameters were scored as absent (0), localized (1), or extensive (2), and their sum formed the composite radiographic index (CRI). RESULTS: DD patients demonstrated minimal radiographic findings, and their CRI was significantly lower than that of NBE and BE patients. Additionally, BE patients demonstrated a higher radiographic index compared with NBE patients. Intriguingly, sequestration was observed in the initial CBCT of 9 (90%) of 10 BE patients, whereas 80% of NBE patients showed absence of sequestration at initial CBCT examination. CONCLUSIONS: CBCT imaging can aid in the differentiation of stage 0 MRONJ from dental disease. Radiographic sequestration at initial presentation can serve as a predictor of future bone exposure in patients with stage 0 MRONJ.

Imaging of Radiation- and Medication-Related Osteonecrosis.

Osteonecrosis is the devitalization of bone and consequent lytic changes. In the jaws, osteonecrosis is a pathologic consequence of prior radiation therapy (osteoradionecrosis) or certain antiresorptive medications. Herein, we review the pathogenesis and clinical manifestations of these lesions, and describe the spectrum of radiologic findings in these conditions, and highlight the similarities and differences between the imaging appearances of these 2 entities.

Facial Trauma: Delayed Development of a Subluxated Traumatic Cataract as Visualized on a Panoramic Image.

The immediate and long-term consequences of blunt orbital trauma leading to a subluxated lens and its subsequent calcification and opacification are reviewed. The accompanying panoramic image documents the process.

Gnathodiaphyseal dysplasia: report of a family with a novel mutation of the ANO5 gene.

Gnathodiaphyseal dysplasia (GDD) is a rare autosomal dominant disorder characterized by florid osseous dysplasia of the jaws, bone fragility, and diaphyseal cortical thickening and bowing of long bones. We present a family with previously undiagnosed GDD. The disorder was identified by the characteristic gnathic and skeletal manifestations in the father. Clinical and radiologic examination of the patient's son also revealed the characteristic features of GDD. Gene sequencing revealed a novel mutation (c. 1067 G>A, p. Cys356 Tyr) in the ANO5 gene, which is causative for GDD. This mutation was predicted to be detrimental by computational analyses and by structural modeling of the protein. The implications for recognition and management of this disease are discussed.

Molar-incisor Malformation: Two Cases of a Newly Described Dental Anomaly.

Molar-incisor malformation (MIM) is a recently described dental developmental anomaly with marked manifestations in the primary second molars and permanent first molars and sometimes the permanent maxillary central incisors. To date, there are only two known manuscripts that present this anomaly. The major manifestations are severe coronal cervical constriction of the affected molars and significant under-development of one or more roots. These abnormalities may be detected during routine radiographic examination or present as altered or ectopic eruption or early exfoliation. The characteristic radiographic features are sufficient to identify this abnormality properly. The purpose of this paper is to present two cases of MIM and discuss the impact of the dental abnormalities on patient management.

Modeling vitamin D insufficiency and moderate deficiency in adult mice via dietary cholecalciferol restriction.

PURPOSE: We sought to develop and characterize a model of human vitamin D nutritional insufficiency/deficiency in the adult mouse, which could have broad utility in examining health consequences of this common condition. METHODS: Adult mice were fed diets containing cholecalciferol contents of 0.05 IU/g, 0.25 IU/g, 0.5 IU/g or 1.5 IU/g for four months. We studied induction of steady-state vitamin D insufficiency, and its consequences on primary cholecalciferol metabolite levels, calcium homeostasis, parathyroid physiology, and bone morphology. RESULTS: All diets were well tolerated, without adverse effects on body weight. Diets containing 0.05 IU/g and 0.25 IU/g cholecalciferol significantly lowered serum 25-hydroxyvitamin D levels (median 25OHD, 10.5 ng/ml, and 21.6 ng/ml, respectively), starting as early as one month following initiation of the diets, maintained through the four-month experimental period. The 0.05 IU/g diet significantly decreased 1,25-dihydroxyvitamin D (1,25OH2D) levels (median, 78 pg/ml). Despite these decreased 25OHD and 1,25OH2D levels, the diets did not alter parathyroid gland morphology or parathyroid cell proliferation. There were no statistical differences in the serum total calcium and serum PTH levels among the various dietary groups. Furthermore, the 0.05 IU/g diet did not cause any alterations in the cortical and trabecular bone morphology, as determined by microCT. CONCLUSIONS: The dietary manipulations yielded states of vitamin D insufficiency or modest deficiency in adult mice, with no overtly detectable impact on parathyroid and bone physiology, and calcium homeostasis. This model system may be of value to study health effects of vitamin D insufficiency/deficiency especially on extraskeletal phenotypes such as cancer susceptibility or immune function.

Intraosseous pneumatocysts of the cervical spine: a report of four cases and review of literature.

Pneumatocysts are benign, gas-containing lesions, most commonly observed affecting the vertebrae, sacrum, and ileum. Most often, these lesions are asymptomatic and are detected incidentally during imaging examinations. Although once believed to be a rare lesion, recent studies suggest that it is more common than previously thought. We present four cases of pneumatocysts affecting the cervical vertebrae detected as incidental findings on cone beam computed tomography (CBCT). Given the increased use of CBCT in dentistry to evaluate the maxillofacial structures, it is likely that dentists will encounter this lesion on CBCT scans that encompass the superior cervical spine. Recognition of the pathognomonic features of this benign, innocuous lesion is important to avoid unnecessary investigations and causing alarm to the patient. We also present a comprehensive review of the literature on the demographic characteristics and clinical presentation of this relatively unknown lesion.

Evidence and Professional Guidelines for Appropriate Use of Cone Beam Computed Tomography.

Cone beam computed tomography (CBCT) has applications in several aspects of dentistry. To appropriately use this technology, clinicians should be able to identify those situations where the information from CBCT is likely to provide useful information, and where this additional information translates into enhanced diagnoses, treatment plans and treatment outcomes. This article summarizes current evidence and recommendations from professional societies that guide safe and effective use of this technology for enhanced patient care.

What are the potential implications of identifying intracranial internal carotid artery atherosclerotic lesions on cone-beam computed tomography? A systematic review and illustrative case studies.

PURPOSE: A systematic literature review was performed to examine the clinical implications of intracranial internal carotid artery calcific atherosclerotic lesions (IICACALs) detected at cone-beam computed tomographic (CBCT) examinations. MATERIALS AND METHODS: The PubMed database was queried in 2 separate searches using the linked search terms non-contrast enhanced cone beam computed tomography and calcified intracranial vascular lesions and non-contrast enhanced computed tomography and calcified intracranial vascular lesions. Reviewed were all English-language articles using CBCT or CT imaging that enrolled neurologically asymptomatic and symptomatic patients. Excluded were studies describing patients with hemorrhagic stroke. Illustrative cases describing incidentally detected IICACALs on CBCT scans are provided. RESULTS: Three articles described identification of IICACALs on CBCT scans of almost 1,500 dental patients. Two of these fully addressed the subject, with 1 noting that IICACALs were benign and another urging patient referral for further workup. Five non-contrast-enhanced CT studies were evaluated in detail; all confirmed IICACALs as a substantive risk marker of advanced stenotic disease in the cerebral circulation, central brain atrophy, concomitant advanced atherosclerotic disease in the cardiovascular circulation, and an indicator of future ischemic events. Five CBCT examinations showing IICACALs in the cavernous and ophthalmic segments are presented. CONCLUSION: Few studies have denoted the importance of identifying IICACALs on CBCT scans. However, all non-contrast-enhanced CT studies emphasized the clinical significance of these lesions in relation to cerebral and cardiovascular disease. Therefore, IICACALs seen on CBCT and CT scans present the same risk and should prompt referral for further evaluation.

Vitamin D signaling regulates oral keratinocyte proliferation in vitro and in vivo.

The secosteroidal hormone 1,25-dihyroxyvitamin D [1,25(OH)(2)D(3)] and its receptor, the vitamin D receptor (VDR), are crucial regulators of epidermal proliferation and differentiation. However, the effects of 1,25(OH)(2)D(3)-directed signaling on oral keratinocyte pathophysiology have not been well studied. We examined the role of 1,25(OH)(2)D(3) in regulating proliferation and differentiation in cultured oral keratinocytes and on the oral epithelium in vivo. Using lentiviral-mediated shRNA to silence VDR, we generated an oral keratinocyte cell line with stable knockdown of VDR expression. VDR knockdown significantly enhanced proliferation and disrupted calcium- and 1,25(OH)(2)D(3)-induced oral keratinocyte differentiation, emphasizing the anti-proliferative and pro-differentiation effects of 1,25(OH)(2)D(3) in oral keratinocytes. Using vitamin D(3)-deficient diets, we induced chronic vitamin D deficiency in mice as evidenced by decreased serum 25-hydroxyvitamin D (25OHD) concentrations. The vitamin D-deficient mice manifested increased proliferation of the tongue epithelium, but did not develop any morphological or histological abnormalities in the oral epithelium, suggesting that vitamin D deficiency alone is insufficient to alter oral epithelial homeostasis and provoke carcinogenesis. Immunohistochemical analyses of human and murine oral squamous cell carcinomas showed increased VDR expression. Overall, our results provide strong support for a crucial role for vitamin D signaling in oral keratinocyte pathophysiology.