A rare case of unilateral double Stafne bone defects and literature review.

Stafne bone defect (SBD) is a rare developmental bone defect characterized by an asymptomatic focal concavity of the cortical bone, typically on the lingual aspect of the mandibular body, which generally contains salivary gland tissue. It can be detected during routine dental examinations and typically appears as an ovoid, well-defined, well-corticated, radiolucent depression in the posterior mandibular region below the inferior alveolar nerve (IAN) (in: Neville et al, Oral and maxillofacial pathology, Elsevier, Inc, St. Louis, MO, 2016).An 80-year-old male presented to our clinic for a routine dental examination. Panoramic radiography and cone-beam computed tomography (CBCT) displayed two well-defined, well-corticated, ovoid radiolucencies inferior to the IAN canal on the left mandibular molar region. The working diagnosis was SBD, and the patient was informed of the findings. Irregular margins on the superior aspect of the anterior defect were noted on CBCT imaging; therefore, follow-up with panoramic images at 6 months, 1 and 5 years was recommended.

The relationship between diabetes and carotid artery calcifications detected via dental cone-beam computed tomography in patients undergoing implant treatment planning.

BACKGROUND: The authors investigated the association between carotid artery calcifications (CACs) detected incidentally on dental cone-beam computed tomographic scans and positive diabetes status. METHODS: Two patient groups were identified retrospectively from a patient database: positive for CACs based on cone-beam computed tomographic scans and positive diabetes status. In addition to demographic characteristics, data including diabetes status and presence, type, and absence of CACs were obtained. A χ2 statistical analysis was completed by means of dividing the data into sets of known CAC and known history of diabetes; significance level was P < .05. RESULTS: To satisfy the a priori power analysis, records from 2010 through 2021 were used. For the positive CAC group, data were obtained from 288 patients (171 men, 117 women) and 68 patients (24%) had a positive diabetes status at the time of cone-beam computed tomography (P < .001). There were significantly more male patients (n = 47) than female patients (n = 21) with diabetes (χ2 = 9.9; P = .002). For the positive diabetes group, data were obtained from 225 patients (149 men, 76 women), and 100 patients (44%) had an identifiable CAC. There were significantly more male patients (n = 73) than female patients (n = 27) with CAC (χ2 = 21.2; P < .001). CONCLUSIONS: There was a significant relationship to diabetes for patients with CACs, indicating potential undiagnosed diabetes. Male patients with diabetes are significantly more at risk of developing CACs. PRACTICAL IMPLICATIONS: People with CAC may be at risk of having undiagnosed diabetes and require heightened awareness during implant treatment planning.

An unusual presentation of osteoblastoma of the maxilla: A case report.

This report presents a rare case of maxillary osteoblastoma in a 17-year-old female. The patient presented with dull pain and facial asymmetry inferior to the left zygoma. An intraoral examination found a painless swelling on the buccal gingival tissue in the left posterior maxilla. Panoramic radiographs and multidetector computed tomographic images revealed an ill-defined, non-corticated, mixed attenuating entity of osseous density located within the left posterior maxilla apical to the left maxillary molars. The entity exhibited a heterogeneous internal structure with a fine granular appearance, and the periphery showed a partial hypo-attenuating rim along the antero-medial aspect. Expansion of the left posterior maxilla accompanied with displacement of the left maxillary sinus floor was noted. External root resorption of the first and second molars was noted, as well as postero-superior displacement of the third molar. The histopathologic diagnosis of the biopsy was osteoblastoma. Complete excision of the tumor was performed.

Guidelines for oral and maxillofacial imaging: COVID-19 considerations.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus causing the current coronavirus disease 2019 (COVID-19) pandemic, is not only highly infectious but can induce serious outcomes in vulnerable individuals including dental patients and dental health care personnel (DHCPs). Responses to COVID-19 have been published by the Centers for Disease Control and Prevention and the American Dental Association, but a more specific response is required for the safe practice of oral and maxillofacial radiology. We aim to review the current knowledge of how the disease threatens patients and DHCPs and how to determine which patients are likely to be SARS-CoV-2 infected; consider how the use of personal protective equipment and infection control measures based on current best practices and science can reduce the risk of disease transmission during radiologic procedures; and examine how intraoral radiography, with its potentially greater risk of spreading the disease, might be replaced by extraoral radiographic techniques for certain diagnostic tasks. This is complemented by a flowchart that can be displayed in all dental offices.

Generation of intra-oral-like images from cone beam computed tomography volumes for dental forensic image comparison.

UNLABELLED: Identification of unknown individuals using dental comparison is well established in the forensic setting. The identification technique can be time and resource consuming if many individuals need to be identified at once. Medical CT (MDCT) for dental profiling has had limited success, mostly due to artifact from metal-containing dental restorations and implants. DESCRIPTION: The authors describe a CBCT reformatting technique that creates images, which closely approximate conventional dental images. METHOD: Using a i-CAT Platinum CBCT unit and standard issue i-CAT Vision software, a protocol is developed to reproducibly and reliably reformat CBCT volumes. The reformatted images are presented with conventional digital images from the same anatomic area for comparison. CONCLUSION: The authors conclude that images derived from CBCT volumes following this protocol are similar enough to conventional dental radiographs to allow for dental forensic comparison/identification and that CBCT offers a superior option over MDCT for this purpose.

Optimising radiographic bitewing examination to adult and juvenile patients through the use of anthropomorphic phantoms.

Four anthropomorphic phantoms (an adult male, an adult female, a 10-y-old child and a 5-y-old child) were exposed to bitewing radiographs at film and digital settings using both rectangular and round collimation. Optically stimulated dosemeters were used. For children, average organ doses were <40 µGy and the organs with the highest doses were the salivary glands, parotid, oral mucosa, skin and extrathoracic airway. For adults, average organ doses were <200 µGy. Highest adult doses were to the salivary glands, oral mucosa and skin. Effective doses ranged from 1.5 to 1.8 µSv for children and from 2.6 to 3.6 µSv for adults when optimised technique factors were employed, including digital receptors, rectangular collimation, size-appropriate exposure times and proper clinical judgment. Optimised doses were a fraction of the natural daily background exposure. Therefore, predictions of hypothetical cancer incidence or detriment in patient populations exposed to such low doses are highly speculative and should be discouraged.

Comparison of adult and child radiation equivalent doses from 2 dental cone-beam computed tomography units.

INTRODUCTION: With the advent of cone-beam computed tomography (CBCT) scans, there has been a transition toward these scans' replacing traditional radiographs for orthodontic diagnosis and treatment planning. Children represent a significant proportion of orthodontic patients. Similar CBCT exposure settings are predicted to result in higher equivalent doses to the head and neck organs in children than in adults. The purpose of this study was to measure the difference in equivalent organ doses from different scanners under similar settings in children compared with adults. METHODS: Two phantom heads were used, representing a 33-year-old woman and a 5-year-old boy. Optically stimulated dosimeters were placed at 8 key head and neck organs, and equivalent doses to these organs were calculated after scanning. The manufacturers' predefined exposure settings were used. RESULTS: One scanner had a pediatric preset option; the other did not. Scanning the child's phantom head with the adult settings resulted in significantly higher equivalent radiation doses to children compared with adults, ranging from a 117% average ratio of equivalent dose to 341%. Readings at the cervical spine level were decreased significantly, down to 30% of the adult equivalent dose. When the pediatric preset was used for the scans, there was a decrease in the ratio of equivalent dose to the child mandible and thyroid. CONCLUSIONS: CBCT scans with adult settings on both phantom heads resulted in higher radiation doses to the head and neck organs in the child compared with the adult. In practice, this might result in excessive radiation to children scanned with default adult settings. Collimation should be used when possible to reduce the radiation dose to the patient. While CBCT scans offer a valuable tool, use of CBCT scans should be justified on a specific case-by-case basis.

Evaluation of radiation exposure with Tru-Align intraoral rectangular collimation system using OSL dosimeters.

A pilot study to compare radiation exposure with the Tru-Align rectangular collimation system to round collimation exposures was undertaken. Radiation exposure at various points within the cross sections of the collimators and entrance, intraoral and exit dose measurements were measured using InLight OSL dosimeters. Overall dose reduction with the use of the rectangular collimation system was estimated by taking into account the ratios of collimator openings and the average radiation exposure at the measurement points. Use of the Tru-Align system resulted in an average radiation exposure within the perimeter of the projected outline of the rectangular collimator of 36.1 mR, compared to 148.5 mR with the round collimator. Our calculations indicate a dose reduction by a factor of approximately 3.2 in the case of the Tru-Align system compared to round collimation. The Tru-Align system was easy to use, but in some situations failed to allow Xray coverage of the entire surface of the image receptor, leading to cone cuts.

Evolution of a humanitarian dental mission to Madagascar from 1999 to 2008.

In this article, we report on the evolution of a series of dental outreach missions sponsored by Stony Brook University to remote areas of Madagascar over a nine-year period. The project evolved from one dental resident performing only dental extractions in 1999 to a team comprised of two dentists, six third-year dental students, and two dental assistants performing dental restorations, extractions, and endodontic procedures using digital radiographic equipment in 2008. The ability during the latest mission to utilize digital radiography in remote areas lacking running water, electricity, and dental facilities significantly enhanced the range and efficacy of dental procedures. This long-term project offered senior dental students and residents from Stony Brook University's School of Dental Medicine an educationally valuable opportunity to engage in international dental outreach and to make a significant contribution to the improvement of oral health in the underserved rural communities of Madagascar.

Comparison of the efficacy and technical accuracy of different rectangular collimators for intraoral radiography.

OBJECTIVE: The objective of this study was to compare the operating efficiency and technical accuracy of 3 different rectangular collimators. STUDY DESIGN: A full-mouth intraoral radiographic series excluding central incisor views were taken on training manikins by 2 groups of undergraduate dental and dental hygiene students. Three types of rectangular collimator were used: Type I ("free-hand"), Type II (mechanical interlocking), and Type III (magnetic collimator). Eighteen students exposed one side of the manikin with a Type I collimator and the other side with a Type II. Another 15 students exposed the manikin with Type I and Type III respectively. Type I is currently used for teaching and patient care at our institution and was considered as the control to which both Types II and III were compared. The time necessary to perform the procedure, subjective user friendliness, and the number of technique errors (placement, projection, and cone cut errors) were assessed. The Student t test or signed rank test was used to determine statistical difference (P

Pilot study: digital subtraction radiography as a tool to assess alveolar bone changes in periodontitis patients under treatment with subantimicrobial doses of doxycycline.

BACKGROUND: Subtle changes in marginal alveolar bone level can be demonstrated using digital subtraction of sequential radiographs. OBJECTIVE: We aimed to evaluate the practical application of geometrically corrected digital subtraction in a clinical study of alveolar bone response to a drug previously shown to inhibit alveolar bone loss. STUDY DESIGN: Selected periapical radiographs were acquired with projective standardization of patients with clinical marginal alveolar bone loss. Subsequently, patients received a 6-month regimen of subantimicrobial doxycycline or placebo. Standardized radiographs of the same alveolar regions were acquired after 3 and 6 months, and baseline radiographs were subtracted from these images. RESULTS: Blinded digital subtraction analysis indicated various levels of marginal bone gain in 3 of the 6 patients in the experimental group, whereas in 3 of the 5 placebo patients the method showed bone loss. CONCLUSION: These results suggest that geometrically corrected digital subtraction possibly agrees with clinical predictors of bone loss severity.

Genomic organization and allelic expression of UBE3A in chicken.

UBE3A, the gene associated with Angelman syndrome, is part of a cluster of genes in the human chromosome 15q11-q13/mouse chromosome 7C region, that is subject to genomic imprinting. In human and mouse brain, UBE3A is expressed predominantly from the maternal allele, and the paternal allele is silenced. A current model concerning the evolution of genomic imprinting, the parental conflict hypothesis, posits that this epigenetic phenomenon is restricted to eutherian mammals. It has been recently reported, however, that several chicken orthologues of mammalian imprinted loci display DNA replication asynchrony, a property of imprinted genes. A separate group also reported monoallelic expression of chicken IGF2 in developing chicken embryos. These observations could suggest that genomic imprinting may occur in chicken. We have assembled the predicted mRNA consensus sequence for the chicken UBE3A gene using published ESTs. We report a high degree of homology with the human UBE3A at the nucleotide and protein levels, as well as a highly conserved genomic organization. Biallelic expression of UBE3A is observed in embryonic chicken brain and limb, indicating that UBE3A is not subject to genomic imprinting in chicken.

Maternal disruption of Ube3a leads to increased expression of Ube3a-ATS in trans.

Angelman syndrome (AS) is a neurogenetic disorder characterized by severe mental retardation, 'puppet-like' ataxic gait with jerky arm movements, seizures, EEG abnormalities, hyperactivity and bouts of inappropriate laughter. Individuals with AS fail to inherit a normal active maternal copy of the gene encoding ubiquitin protein ligase E3A (UBE3A). UBE3A is transcribed predominantly from the maternal allele in brain, but is expressed from both alleles in most other tissues. It has been proposed that brain-specific silencing of the paternal UBE3A allele is mediated by a large (>500 kb) paternal non-coding antisense transcript (UBE3A-ATS). There are several other examples of imprinting regulation involving antisense transcripts that share two main properties: (i) the sense transcript is repressed by antisense and (ii) the interaction between sense and antisense occurs in cis. We show here that, in a mouse model of AS, maternal transmission of Ube3a mutation leads to increased expression of the paternal Ube3a-ATS, suggesting that the antisense is modulated by sense rather than the reciprocal mode of regulation. Our observation that Ube3a regulates expression of Ube3a-ATS in trans is in contrast to the other cases of sense-antisense epigenetic cis-interactions and argues against a major role for Ube3a-ATS in the imprinting of Ube3a.

Brief communication: Bone trabeculae are visible on periapical images.

It is traditionally believed that the radiographic image of bone striae is a reflection of the trabecular pattern of cancellous bone. Results of a 1999 paper by Cavalcanti et al. contradicted this paradigm, suggesting that the intraoral radiographic image of trabecular pattern in the mandible reflects the morphology of the endosteal surface of the cortical bone, rather than that of cancellous bone. Here, we conduct a simple experiment to assess the contribution of dry mandibular cancellous bone to the image of trabecular pattern seen on intraoral films. Standardized periapical-type radiographs centered on the same region of interest of a dry human mandible were acquired before and after removal of the buccal, then of both cortical plates, together with the endosteal cortical-trabecular bone interface. One oral and maxillofacial radiologist and 4 oral and maxillofacial radiology residents blindly assessed the presence or absence of bone striations on the acquired images. We find that bone striations are visible on periapical-type images of dry human mandibles in the absence of one or both cortical plates, and that their pattern is similar to that seen in the image of the intact specimen. We conclude that cancellous bone contributes significantly to the image of trabecular bone in dry human mandibles.