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OBJECTIVE: The objective of this study was to examine the suitability of optically stimulated luminescent dosimeters (OSLD) for point dosimetry of maxillofacial radiographic examinations. STUDY DESIGN: The dose response of OSLD nanoDot dosimeters was evaluated over the range of 10 [mu]Gy to 4900 [mu]Gy x-radiation. The angular dependence of the OSLD nanoDots was examined and compared with that of thermoluminescent dosimeter (TLD) chips. The concordance between OSDL- and TLD-measured absorbed doses at selected anatomic sites in an anthropomorphometric phantom was examined. RESULTS: OSLD-measured doses were not significantly different from the actual delivered dose, as determined by an ionization chamber. The dose response is linear over the dose response over the examined dose range. Angular variation of OSLD dosimeters ranged from 88% to 109%; however, the magnitude of this variation was not significantly different from that of TLDs. There was a good concordance between OSLD- and TLD-measured absorbed doses. CONCLUSIONS: The OSLD nanoDots dosimeter system performs as well as currently used TLD systems and effective dose estimates using this new system did not differ significantly from current TLD-based dose estimates. [ABSTRACT FROM AUTHOR]

We present a case that describes the radiographic findings of Radiesse, a calcium hydroxyapatitie-based dermal filler. This dermal filler was detected during radiographic examination for implant treatment planning. This case illustrates the typical radiographic appearance of this material and the importance of differentiating it from pathological conditions. [ABSTRACT FROM AUTHOR]

Objective: To assess quantitatively the effect of metallic materials on MR image uniformity using a standardized method., Methods: Six types of 1 cm cubic metallic materials (i.e., Au, Ag, Al, Au-Ag-Pd alloy, Ti, and Co-Cr alloy) embedded in a glass phantom filled were examined and compared with no metal condition inserted as a reference. The phantom was scanned five times under each condition using a 1.5-T MR superconducting magnet scanner with an 8-channel phased-array brain coil and head and neck coil. For each examination, the phantom was scanned in three planes: axial, coronal, and sagittal using T1-weighted spin echo (SE) and gradient echo (GRE) sequences in accordance with the American Society for Testing and Materials (ASTM) F2119-07 standard. Image uniformity was assessed using the non-uniformity index (NUI), which was developed by the National Electrical Manufacturers Association (NEMA), as an appropriate standardized measure for investigating magnetic field uniformity., Results: T1-GRE images with Co-Cr typically elicited the lowest uniformity, followed by T1-GRE images with Ti, while all other metallic materials did not affect image uniformity. In particular, T1-GRE images with Co-Cr showed significantly higher NUI values as far as 6.6 cm at maximum equivalent to 11 slices centering around it in comparison with the measurement uncertainty from images without metallic materials., Conclusion: We found that MR image uniformity was influenced by the scanning sequence and coil type when Co-Cr and Ti were present. It is assumed that the image non-uniformity in Co-Cr and Ti is caused by their high magnetic susceptibility., (© 2024. The Author(s).)

Objectives: To evaluate magnetic susceptibility artefacts produced by orthodontic wires on MRI and the influence of wire properties and MRI image sequences on the magnitude of the artefact., Methods: Arch form orthodontic wires [four stainless steels (SS), one cobalt chromium (CC) alloy, 13 titanium (Ti) alloys] were embedded in a polyester phantom, and scanned using a 1.5-T superconducting magnet scanner with an eight-channel phased-array coil. All wires were scanned with T1-weighted spin echo (SE) and gradient echo (GRE) sequences according to the American Society for Testing and Materials (ASTM) F2119-07 standard. The phantom also scanned other eight sequences. Artefacts were measured using the ASTM F2119-07 definition and OsiriX software. Artefact volume was analysed according to metal composition, wire length, number of wires, wire thickness, and imaging sequence as factors., Results: With SE/GRE, black/white artefacts volumes from all SS wires were significantly larger than those produced by CC and Ti wires (P < .01). With the GRE, the black artefacts volume was the highest with the SS wires. With the SE, the black artefacts volume was small, whereas white artefacts were noticeable. The cranio-caudal extent of the artefacts was significantly longer with SS wires (P < .01). Although a direct relationship of wire length, number of wires, and wire thickness with artefact volume was noted, these factors did not influence artefact extension in the cranio-caudal direction., Conclusions: Ferromagnetic/paramagnetic orthodontic wires create artefacts due to local alteration of magnetic field homogeneity. The SS-type wires produced the largest artefacts followed by CC and Ti., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology and the International Association of Dentomaxillofacial Radiology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: The American Association of Endodontists (AAE) and the American Academy of Oral and Maxillofacial Radiology (AAOMR) developed guidelines for the prescription of cone-beam computed tomographic (CBCT) imaging. The impact of appropriately prescribed CBCT imaging on endodontic diagnosis and treatment (Tx) decisions was examined., Methods: The clinical databases at the School of Dentistry at the University of California, Los Angeles, Los Angeles, California, were queried to identify patients referred for CBCT imaging from the postgraduate endodontic clinic over a consecutive 36-month period. Primary and secondary indications for CBCT imaging were recorded. Pre-CBCT uncertainty in diagnosis, Tx of the teeth in question, and post-CBCT changes to the diagnosis and Tx plan were recorded., Results: CBCT imaging was prescribed for 12% of patients. A total of 442 scans were prescribed to evaluate 526 teeth. Molars accounted for 51% of teeth examined. Overall, CBCT effected a change in periapical diagnosis (21%) and in the Tx plan (69%). The 5 most frequent primary indications for CBCT imaging were, in order, AAE-AAOMR recommendations 7, 9, 2, 12, and 6. The impact of these recommendations on Tx decisions varied from 48% through 93%., Conclusions: This study validates the use of the AAE-AAOMR guidelines for prescribing CBCT imaging for endodontic evaluations. CBCT imaging contributed predominantly to Tx decisions rather than diagnostic determinations., Practical Implications: This study validates AAE-AAOMR case selection guidelines for CBCT imaging and shows a positive impact of prescription imaging on endodontic decision making., Competing Interests: Disclosures None of the authors reported any disclosures., (Copyright © 2024 American Dental Association. Published by Elsevier Inc. All rights reserved.)

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., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

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., (Copyright © 2023 American Dental Association. Published by Elsevier Inc. All rights reserved.)

Introduction: Root resorption is a destructive process that compromises tooth structure and can result in tooth loss. Often it remains asymptomatic and is an incidental finding on radiographic examinations. The purpose of this study was to determine prevalence and characteristics of root resorption in patients referred for cone-beam computed tomography (CBCT) imaging for a variety of indications., Methods: The study included CBCT scans of 1086 consecutive patients referred for CBCT imaging over an 18-month period. A total of 1148 scans were acquired. Data were abstracted from radiology reports, and prevalence estimates of resorption were computed for the aggregate sample and also across specific indications., Results: Resorption was identified in 171 patients (15.7%, 95% CI: 13.6%-17.9%) and in 249 teeth with a prevalence range of 2.6%-92.3% across specific indications. An 18.7% of the patients had 2 resorption sites whereas 8.8% had 3 or more resorption sites. The majority of affected teeth were anteriors (43.8%), followed by molars (40.6%) and premolars (14.5%). The most prevalent resorption types were external (29.3%), cervical (22.5%), infection-induced apical resorption (13.7%), internal (9.6%), and impacted tooth induced (8.8%). The majority of teeth with resorption did not have prior endodontic treatment (73.9%) and had radiographically normal periapex (69.5%). Of 249 teeth with resorption, 31% presented as incidental finding. The prevalence of incidental findings of resorption increased with age, P < .05, and was significantly lower for anterior teeth (20.2%) as compared to premolars (41.7%) and molars (36.6%), (P < .05)., Conclusion: The high proportion of incidental findings of resorption detected by CBCT suggests that resorption is not recognized/detected by conventional radiography and therefore remains underdiagnosed., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Imaging findings are central to the diagnosis and treatment planning decisions when managing craniofacial differences. However, limited information is published on protocols for systematic cleft imaging assessment and for effective communication of these findings., Solution: A template is presented to help guide radiologic imaging reports to acquire the relevant clinical information needed to manage patients with alveolar cleft.

Introduction: Root resorption is a destructive process that compromises tooth structure and can result in tooth loss. Often it remains asymptomatic and is an incidental finding on radiographic examinations. The purpose of this study was to determine prevalence and characteristics of root resorption in patients referred for cone-beam computed tomography (CBCT) imaging for a variety of indications., Methods: The study included CBCT scans of 1086 consecutive patients referred for CBCT imaging over an 18-month period. A total of 1148 scans were acquired. Data were abstracted from radiology reports, and prevalence estimates of resorption were computed for the aggregate sample and also across specific indications., Results: Resorption was identified in 171 patients (15.7%, 95% CI: 13.6%-17.9%) and in 249 teeth with a prevalence range of 2.6%-92.3% across specific indications. An 18.7% of the patients had 2 resorption sites whereas 8.8% had 3 or more resorption sites. The majority of affected teeth were anteriors (43.8%), followed by molars (40.6%) and premolars (14.5%). The most prevalent resorption types were external (29.3%), cervical (22.5%), infection-induced apical resorption (13.7%), internal (9.6%), and impacted tooth induced (8.8%). The majority of teeth with resorption did not have prior endodontic treatment (73.9%) and had radiographically normal periapex (69.5%). Of 249 teeth with resorption, 31% presented as incidental finding. The prevalence of incidental findings of resorption increased with age, P < .05, and was significantly lower for anterior teeth (20.2%) as compared to premolars (41.7%) and molars (36.6%), (P < .05)., Conclusion: The high proportion of incidental findings of resorption detected by CBCT suggests that resorption is not recognized/detected by conventional radiography and therefore remains underdiagnosed., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

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 the pertinent literature and drafted recommendations for imaging. This joint statement provides evidence-based recommendations and clinical guidance for applying appropriate diagnostic imaging to evaluate the temporomandibular joint (TMJ). This manuscript guides the design of TMJ imaging examinations, addresses in-office CBCT imaging, and provides timely evidence-based recommendations to evaluate the TMJ bony components, also addressing the use of MRI and other modalities to evaluate TMJ involvement in different pathologic conditions.

Background: Digital intraoral radiographic exposures are optimized largely on the basis of subjective assessment of diagnostic image quality. This study presents an objective approach to optimize radiographic exposure settings for digital intraoral radiographic systems., Methods: Seven size 2 digital intraoral systems were assessed for image quality and determination of optimal exposure following the protocol specified in American National Standard Institute/American Dental Association Standard No. 1094: Quality Assurance for Digital Intra-Oral Radiographic Systems. A ProX radiograph unit (Planmeca) at 63 kVp and 6 mA was used to obtain radiographs of the Dental Digital Quality Assurance phantom. ImageJ software (National Institutes of Health) was used to quantify dynamic range and spatial resolution, and contrast perceptibility was evaluated visually. Optimal exposure is the setting with the maximal contrast perceptibility and spatial resolution while displaying the full dynamic range. After image optimization, a custom phantom consisting of an endodontically prepared tooth was imaged to evaluate the file position relative to the apex for each system. Differences in distances between file position relative to the root apex at the optimal exposure as well as 1 increment above and below were measured., Results: Radiographic images obtained at the optimal exposure yielded better visualization and more accurate measurements of the file tip relative to the apex., Conclusions: Optimizing radiographic exposures improves image quality and accuracy in clinical decisions., Practical Implications: Improvement in image quality and better accuracy in actual distance of the endodontic file to the radiographic apex coupled with complete cleaning, shaping, and obturation of the canal should lead to better endodontic treatment outcomes., (Copyright © 2023 American Dental Association. Published by Elsevier Inc. All rights reserved.)

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., (© 2022. The Author(s) under exclusive licence to Japanese Society for Oral and Maxillofacial Radiology.)

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., (Copyright © 2022 Elsevier Inc. All rights reserved.)

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., (© 2022 American Academy of Periodontology.)

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., (© 2021. The Author(s).)

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., (Copyright © 2020 Elsevier Inc. All rights reserved.)

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., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Miniscrew-assisted rapid palatal expansion (MARPE) has been adopted in recent years to expand the maxilla in late adolescence and adult patients. Maxillary Skeletal Expander (MSE) is a device that exploits the principles of skeletal anchorage to transmit the expansion force directly to the maxillary bony structures and is characterized by the miniscrews' engagement of the palatal and nasal cortical bone layers. In the literature, it has been reported that the zygomatic buttress is a major constraint that hampers the lateral movement of maxilla, since maxilla is located medially to the zygomatic arches. The objective of the present study is to analyze the changes in the zygomatic bone, maxillary bone, and zygomatic arches and to localize the center of rotation for the zygomaticomaxillary complex in the horizontal plane after treatment with MSE, using high-resolution cone-beam computed tomography (CBCT) images., Methods: Fifteen subjects with a mean age of 17.2 (± 4.2) years were treated with MSE. CBCT records were taken before and after miniscrew-assisted maxillary expansion; three linear and four angular parameters were identified in the axial zygomatic section (AZS) and were compared from pre-treatment to post-treatment using the Wilcoxon signed rank test., Results: Anterior inter-maxillary distance increased by 2.8 mm, posterior inter-zygomatic distance by 2.4 mm, angle of the zygomatic process of the temporal bone by 1.7° and 2.1° (right and left side) (P < 0.01). Changes in posterior inter-temporal distance and zygomaticotemporal angle were negligible (P > 0.05)., Conclusions: In the horizontal plane, the maxillary and zygomatic bones and the whole zygomatic arch were significantly displaced in a lateral direction after treatment with MSE. The center of rotation for the zygomaticomaxillary complex was located near the proximal portion of the zygomatic process of the temporal bone, more posteriorly and more laterally than what has been reported in the literature for tooth-borne expanders. Bone bending takes place in the zygomatic process of the temporal bone during miniscrew-supported maxillary expansion.

Introduction: Our objectives were to evaluate midfacial skeletal changes in the coronal plane and the implications of circummaxillary sutures and to localize the center of rotation for the zygomaticomaxillary complex after therapy with a bone-anchored maxillary expander, using high-resolution cone-beam computed tomography., Methods: Fifteen subjects with a mean age of 17.2 ± 4.2 years were treated with a bone-anchored maxillary expander. Pretreatment and posttreatment cone-beam computed tomography images were superimposed and examined for comparison., Results: Upper interzygomatic distance increased by 0.5 mm, lower interzygomatic distance increased by 4.6 mm, frontozygomatic angles increased by 2.5° and 2.9° (right and left sides), maxillary inclinations increased by 2.0° and 2.5° (right and left sides), and intermolar distance increased by 8.3 mm (P <0.05). Changes in frontoethmoidal, zygomaticomaxillary, and molar basal bone angles were negligible (P >0.05)., Conclusions: A significant lateral displacement of the zygomaticomaxillary complex occurred in late adolescent patients treated with a bone-anchored maxillary expander. The zygomatic bone tended to rotate outward along with the maxilla with a common center of rotation located near the superior aspect of the frontozygomatic suture. Dental tipping of the molars was negligible during treatment., (Copyright © 2018 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

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., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Mini-implant-assisted rapid palatal expansion (MARPE) appliances have been developed with the aim to enhance the orthopedic effect induced by rapid maxillary expansion (RME). Maxillary Skeletal Expander (MSE) is a particular type of MARPE appliance characterized by the presence of four mini-implants positioned in the posterior part of the palate with bi-cortical engagement. The aim of the present study is to evaluate the MSE effects on the midpalatal and pterygopalatine sutures in late adolescents, using high-resolution CBCT. Specific aims are to define the magnitude and sagittal parallelism of midpalatal suture opening, to measure the extent of transverse asymmetry of split, and to illustrate the possibility of splitting the pterygopalatine suture., Methods: Fifteen subjects (mean age of 17.2 years; range, 13.9-26.2 years) were treated with MSE. Pre- and post-treatment CBCT exams were taken and superimposed. A novel methodology based on three new reference planes was utilized to analyze the sutural changes. Parameters were compared from pre- to post-treatment and between genders non-parametrically using the Wilcoxon sign rank test. For the frequency of openings in the lower part of the pterygopalatine suture, the Fisher's exact test was used., Results: Regarding the magnitude of midpalatal suture opening, the split at anterior nasal spine (ANS) and at posterior nasal spine (PNS) was 4.8 and 4.3 mm, respectively. The amount of split at PNS was 90% of that at ANS, showing that the opening of the midpalatal suture was almost perfectly parallel antero-posteriorly. On average, one half of the anterior nasal spine (ANS) moved more than the contralateral one by 1.1 mm. Openings between the lateral and medial plates of the pterygoid process were detectable in 53% of the sutures (P < 0.05). No significant differences were found in the magnitude and frequency of suture opening between males and females. Correlation between age and suture opening was negligible (R 2 range, 0.3-4.2%)., Conclusions: Midpalatal suture was successfully split by MSE in late adolescents, and the opening was almost perfectly parallel in a sagittal direction. Regarding the extent of transverse asymmetry of the split, on average one half of ANS moved more than the contralateral one by 1.1 mm. Pterygopalatine suture was split in its lower region by MSE, as the pyramidal process was pulled out from the pterygoid process. Patient gender and age had a negligible influence on suture opening for the age group considered in the study.

The primary goal of conventional endodontic treatment is prevention and/or elimination of apical periodontitis for both mature permanent teeth and immature teeth with an open apex. Besides these goals, the objectives of endodontic treatment of immature teeth include preservation of pulp vitality and often further root maturation. Robust criteria for outcome assessment are an essential determinant for any measure of treatment success for both mature and immature teeth., (Copyright © 2016 Elsevier Inc. All rights reserved.)

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., (Published by Elsevier Inc.)

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 (1,25OH 2 D) levels (median, 78 pg/ml). Despite these decreased 25OHD and 1,25OH 2 D 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.

25-Hydroxyvitamin D (25D) circulates bound primarily to serum vitamin D binding protein (DBP), with DBP showing higher binding affinity for 25D3 than 25D2. We therefore hypothesized that vitamin D2 (D2) promotes higher serum levels of unbound 25D (free 25D), with different functional responses, relative to vitamin D3 (D3). Week 3 C56BL/6 mice were placed on diets containing either D2 or D3 alone (both 1000 IU/kg). At week 8 and week 16, D2 mice had only 25D2 in circulation (26.6 ± 1.9 and 33.3 ± 4.4 ng/mL), and D3 mice had only 25D3 (28.3 ± 2.0 and 31.7 ± 2.1 ng/mL). At week 8 (44.5 ± 6.4 vs 62.4 ± 11.6 pg/mL, P < .05) and week 16 (78.4 ± 12.6 vs 95.5 ± 11.6), D2 mice had lower serum 1,25-dihydroxyvitamin D relative to D3 mice. By contrast, measured free 25D was significantly higher in D2 mice at week 8 (16.8 ± 0.65 vs 8.4 ± 0.63 pg/mL, P < .001) and week 16 (17.4 ± 0.43 vs 8.4 ± 0.44, P < .001). A two-way ANOVA of bone histomorphometry showed that week 8 D2 mice had significantly higher osteoclast surface/bone surface, eroded surface/bone surface, and mineral apposition rate compared with D3 mice. Osteoblast surface/bone surface was higher in week 8 D2 females but not week 8 D2 males. At week 16, D2 mice had significantly higher bone volume/total volume and trabecular number compared with D3 mice. Differences in bone phenotype were observed despite D2 mice reaching similar serum 25D levels and lower 1,25D levels compared with D3 mice. These data indicate that 25D2 binds less well to DBP than 25D3, with resulting higher levels of free 25D promoting differential effects on bone in mice exposed to D2 alone.

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., (Copyright © 2016 Elsevier Inc. All rights reserved.)

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.

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.

Cone beam computed tomography (CBCT) has several applications in dentomaxillofacial diagnosis. Frequently, the imaged volume encompasses the upper airway. This article provides a systematic approach to airway analysis and the implications of the anatomic and pathologic alterations. It discusses the role of CBCT in management of obstructive sleep apnea (OSA) patients. This paper also highlights technological advances that combine CBCT imaging with computational modeling of the airway and the potential clinical applications of such technologies.

Idiopathic condylar resorption (ICR) is progressive resorption of the condyle of unknown aetiology. There is no consensus on the approaches for diagnostic imaging and management of this disease. The objective of this systematic review was to examine the best practices for imaging and to appraise the success of surgical and non-surgical therapy of ICR. Eleven search engines were queried via explicit literature searches for studies describing ICR, published until 2012. Two authors independently extracted data using predetermined characteristics. Studies that identified patients as having either ICR or progressive condylar resorption and that described the radiographic findings or treatment options were included. Seventeen studies contributing 178 cases met the eligibility criteria. The major radiographic findings, as assessed mostly by two-dimensional imaging, included decreased ramus height, decreased condylar height, altered volume of the condyle, decreased SNB angle and mandibular plane angle, and a retrognathic profile. Treatments included occlusal splints with orthodontic treatment, condylectomy with costochondral graft, and other surgical approaches. This systematic review was limited by the lack of meta-analysis. Nevertheless, we identified the need for future investigations: characterization of findings on three-dimensional imaging and its contribution to treatment planning, outcomes of non-surgical and pharmacological management of ICR, and randomized trials and comparative studies with longer follow-up periods., (Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. All rights reserved.)

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., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Purpose: To assess the influence of anatomic location on the relationship between computed tomography (CT) number and X-ray attenuation in limited and medium field-of-view (FOV) scans., Materials and Methods: Tubes containing solutions with different concentrations of K2HPO4 were placed in the tooth sockets of a human head phantom. Cone-beam computed tomography (CBCT) scans were acquired, and CT numbers of the K2HPO4 solutions were measured. The relationship between CT number and K2HPO4 concentration was examined by linear regression analyses. Then, the variation in CT number according to anatomic location was examined., Results: The relationship between K2HPO4 concentration and CT number was strongly linear. The slopes of the linear regressions for the limited FOVs were almost 2-fold lower than those for the medium FOVs. The absolute CT number differed between imaging protocols and anatomic locations., Conclusion: There is a strong linear relationship between X-ray attenuation and CT number. The specific imaging protocol and anatomic location of the object strongly influence this relationship.

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., (Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. All rights reserved.)

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.

Objective: To assess the influence of anatomical location on computed tomography (CT) numbers in mid- and full field of view (FOV) cone beam computed tomography (CBCT) scans., Study Design: Polypropylene tubes with varying concentrations of dipotassium hydrogen phosphate (K₂HPO₄) solutions (50-1200 mg/mL) were imaged within the incisor, premolar, and molar dental sockets of a human skull phantom. CBCT scans were acquired using the NewTom 3G and NewTom 5G units. The CT numbers of the K₂HPO₄ phantoms were measured, and the relationship between CT numbers and K₂HPO₄ concentration was examined. The measured CT numbers of the K₂HPO₄ phantoms were compared between anatomical sites., Results: At all six anatomical locations, there was a strong linear relationship between CT numbers and K₂HPO₄ concentration (R(2)>0.93). However, the absolute CT numbers varied considerably with the anatomical location., Conclusion: The relationship between CT numbers and object density is not uniform through the dental arch on CBCT scans., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: To examine the relationship between dental cone beam computed tomography (CBCT) gray scale values and Hounsfield units (HU), and whether the gray values of edentulous sites correlate with the subjective clinical bone quality assessed at surgery., Materials and Methods: Two radiographic phantoms containing varying concentrations of either dipotassium hydrogen phosphate or calcium hydroxyapatite (HA) were imaged using multislice CT or CBCT. Reconstructed DICOM data were analyzed to examine the relationship between CBCT gray values and HU. Presurgical CBCT scans from 52 patients who underwent implant placement in the posterior sextants were used. The gray values of the edentulous implant sites were measured and compared with the subjective bone quality assessed at surgery., Results: There was a strong correlation between CBCT gray values and HU. CBCT gray values increased linearly with increasing calcium HA or bone equivalent density material. CBCT gray values measured at edentulous implant sites ranged from -455 to 642, with a trend of decreasing gray values with bone quality type. The median gray values for the four subjective bone types were: 362 (type 1), 214 (type 2), 76 (type 3), and -454 (type 4)., Conclusions: CBCT gray values can be used to infer bone density and may provide a valuable aid to predict bone quality at potential implant sites.

Introduction: In this study, we examined the influence of field of view (FOV) and voxel size on the diagnostic efficacy of cone-beam computed tomography (CBCT) scans to detect erosions in the temporomandibular joint (TMJ)., Methods: The sample consisted of 16 TMJs containing natural or artificially created erosions and 16 normal TMJs. CBCT scans were obtained with 3 imaging protocols differing in the FOV and the size of the reconstructed voxels. Two oral and maxillofacial radiologists scored the scans for the presence or absence of erosions. Diagnostic efficacies of the 3 imaging protocols were compared by using receiver operating curve analysis. For each TMJ imaging protocol, we used thermoluminescent dosimetry chips to measure the absorbed dose at specific organ and tissue sites. Effective doses for each examination were calculated., Results: Areas under the receiver operating characteristic curves were 0.77 ± 0.05 for the 6-in FOV, 0.70 ± 0.08 for the 9-in FOV, and 0.66 ± 0.05 for the 12-in FOV. The diagnostic efficacy of the 6-in FOV, determined by the area under the curve, was significantly higher than that of the 12-in FOV (P ≤0.05). Effective doses for bilateral TMJ evaluation were 558 μSv for the 6-in FOV, 548 μSv for the 9-in FOV, and 916 μSv for the 12-in FOV., Conclusions: The diagnostic efficacy of CBCT scans for the evaluation of erosive changes in the TMJ is highest for the 6-in FOV and lowest for the 12-in FOV., (Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Maintenance of oral epithelial homeostasis requires a fine balance between cell proliferation and differentiation. However, the molecular mechanisms that couple these processes, and its deregulation in tumorigenesis are not fully understood. Cyclin D1 and its kinase partners CDK4 and CDK6 play an important role in regulating the G1-S phase of the cell cycle. Deregulation of cyclin D1 is a frequent event in oral squamous cell carcinoma. Here, we examined whether overexpression of cyclin D1, CDK4 and CDK6 can deregulate the link between oral keratinocyte proliferation and differentiation. Our results show that cyclin D1 and its kinase partners CDK4 and CDK6 enhance keratinocyte proliferation, but are not sufficient to block calcium-induced keratinocyte differentiation and suggest that deregulation of these G1-regulatory kinases alone is insufficient to uncouple the link between proliferation and differentiation.

Parathyroid adenomas can contain clonal rearrangements of chromosome 11 that activate the cyclin D1 oncogene through juxtaposition with the PTH gene. Here we describe such a chromosomal rearrangement whose novel features provide clues to locating elusive cis-regulatory elements in the PTH gene and also expand the physical spectrum of pathogenetic breakpoints in the cyclin D1 gene region. Southern blot analyses of the parathyroid adenoma revealed rearrangement in the PTH gene locus. Analysis of rearranged DNA clones that contained the breakpoint, obtained by screening a tumor genomic library, pinpointed the breakpoint in the PTH locus 3.3 kb upstream of the first exon. Accordingly, highly conserved distal elements of the PTH 5' regulatory region were rearranged at the breakpoint approximately 450 kb upstream of the cyclin D1 oncogene, resulting in overexpression of cyclin D1 mRNA. Thus, PTH-cyclin D1 gene rearrangement breakpoints in parathyroid tumors can be located far from those previously recognized. In addition to expanding the molecular spectrum of pathogenetic chromosomal lesions in this disease, features of this specific rearrangement reinforce the existence of one or more novel cis-enhancer/regulatory elements for PTH gene expression and narrow their location to a 1.7-kb DNA segment in the distal PTH promoter., (Copyright © 2010 American Society for Bone and Mineral Research.)

Objectives: It is well established that fibrous dysplasia (FD) is caused by mutations of the Arg(201) codon of the GNAS gene. However, the role of GNAS mutation in the pathogenesis of cement-osseous dysplasias (COD) and cemento-ossifying fibromas (COF) is not fully known. In this study, we examined COD and COF for mutations at the Arg(201) codon of the GNAS gene., Study Design: The study sample included formalin-fixed, paraffin-embedded tissue blocks from 8 COF and 24 COD. We used 2 PCR-RFLP methods to detect mutations at the Arg(201) codon of the GNAS gene., Results: Mutations at the Arg(201) codon of the GNAS gene were not present in any of the COD and COF examined., Conclusions: GNAS mutations do not play a role in the pathogenesis of COD and COF. This highlights a clear molecular distinction between FD and other histologically similar fibro-osseous lesions of the jaws., (Copyright (c) 2010 Mosby, Inc. All rights reserved.)

The cyclin D1 oncogene is frequently amplified/overexpressed in oral squamous cell carcinomas. Mice with overexpression of cyclin D1 targeted to the stratified squamous epithelia of the tongue, esophagus, and forestomach develop a phenotype of epithelial dysplasia at these sites. In this study, we examined the effect of cyclin D1 overexpression on susceptibility of mice to carcinogen-induced tumorigenesis, using 4-nitroquinoline-1-oxide (4NQO), an established potent oral carcinogen in mice. Cyclin D1 overexpressing mice and nontransgenic littermates were administered 4NQO (20 or 50 parts per million (ppm) in the drinking water) for 8 wk and monitored for an additional 16 wk. Histopathological analyses of the tongue revealed significantly higher severity of dysplasia in the cyclin D1 overexpression mice, compared with nontransgenic controls and with untreated controls. Moreover, only the cyclin D1 overexpression mice developed neoplastic lesions in the oro-esophageal epithelia. Examination of the dysplastic and neoplastic lesions revealed abnormal proliferation. Our findings suggest that cyclin D1 overexpression enhances susceptibility to carcinogen-induced oral tumorigenesis. These results underscore the importance of cyclin D1 in the process of oral neoplastic development. Further, they emphasize the value of this transgenic model to study the pathogenesis of oral precancer and cancer and establish it as a model system to test candidate agents for chemoprevention of upper aero-digestive cancer.

Objective: To determine the effects of three anesthetic regimens on serum calcium and parathyroid hormone (PTH) in mice., Study Design: Prospective experimental study., Animals: Twenty-seven, 12-week-old, FVB mice., Methods: Mice were anesthetized with either isoflurane, a combination of ketamine plus xylazine (100 and 10 mg kg(-1), respectively) or ketamine alone (100 mg kg(-1)). Blood was collected before and after the induction of anesthesia. Serum calcium and PTH concentrations were measured and compared., Results: Isoflurane or ketamine did not significantly alter either serum calcium or serum PTH concentrations. A combination of ketamine plus xylazine significantly increased serum PTH, but not serum calcium concentrations., Conclusions: A combination of ketamine and xylazine should be avoided prior to collection of blood for measurement of serum PTH concentrations. Isoflurane is suitable for this purpose.