Bone quality assessment in patients with healing mandibular fracture sites: a computed tomography investigation.

The objective of this retrospective study was to assess the bone quality of healing mandibular fracture sites by measuring the Hounsfield units (HU) on computed tomographic (CT) images obtained presurgery and postsurgery in patients treated with rigid internal fixation (RIF). The HU values of healing fracture sites were compared to those of corresponding nonfractured (control) sites on the opposing side and cervical vertebrae sites in the same patients. In total, 31 patients with 45 mandibular fractures treated with RIF underwent presurgical and postsurgical CT examinations. The scans performed after surgery (1, 3, 6, 12, or 18 months) were taken only when there was a need for radiographic evaluation due to a complaint of discomfort from the patient or when the surgeon needed to verify the postsurgical outcome, and each patient underwent only a single postsurgical CT. At the presurgical CT examination, the HU values were lower in the fracture sites than in the control sites. At 3 months postsurgery, the HU values in the fracture sites had increased as the mandibular bone healed. At 6 months postsurgery, the HU values in the fracture sites were higher than those of the control sites. At 12 and 18 months postsurgery, the HU values of both sites were similar. The HU values of the cervical vertebrae remained constant with time. These results suggest that, in patients who have been treated with RIF for mandibular bone fracture, HU values measured by CT vary across time, expressing the physiologic bone healing process.

Inflammatory Modifications in Paranasal Sinuses and Ostiomeatal Complex Anatomical Variations in Jet Aircraft Pilots: A Computed Tomography Study.

Introduction Jet aircraft pilots are exposed to huge pressure variation during flight, which affect physiological functions as systems, such as the respiratory system. Objectives The objective of the present investigation was to evaluate inflammatory changes of paranasal sinuses of jet aircraft pilots before and after a jet aircraft training program, using multislice computed tomography (CT), in comparison with a group of nonairborne individuals with the same age, sex, and physical health conditions. A second objective of the present study was to assess the association between the ostiomeatal complex obstruction and its anatomical variations. Methods The study group consisted of 15 jet aircraft pilots participating in the training program. The control group consisted of 41 nonairborne young adults. The 15 fighter pilots were evaluated before initiating the training program and after their final approval for the presence of inflammatory paranasal sinus disease. The ostiomeatal complex anatomical variations and obstructions were analyzed in pilots after the training program. Results Jet aircraft pilots presented higher incidence of mucosal thickening in maxillary sinus and anterior ethmoid cells than controls. Prominent ethmoidal bulla showed significant association with obstruction of the osteomeatal complex. Conclusions Jet aircraft pilots present increased inflammatory disease when compared with nonairborne individuals. The presence of a prominent ethmoidal bulla is associated with ostiomeatal complex obstruction.

Bone pattern changes in post liver transplant patients using bisphosphonates.

OBJECTIVE: To identify radiographic findings suggestive of drug-induced osteonecrosis and evaluate radiomorphometric patterns indicative of changes in bone mineral density in individuals transplanted for liver disorders using bisphosphonates. STUDY DESIGN: The study group included panoramic x-rays of liver transplant patients who are being monitored and who present a clinical status of osteoporosis and use bisphosphonates. The control group was made up of liver transplant patients who did not have osteoporosis. On panoramic radiographs, mental index (MI) and mandibular cortical index (MCI) and the presence of radiographic anomalies suggestive of osteonecrosis were evaluated. RESULTS: There were significant statistical results when comparing the groups in relation to the decrease in bone mineral density (BMD) with MCI-C3 (p = 0.036), however, there were none in relation to MI (p = 0.14). There were no valid statistical results when relating MCI (p = 0.94) and MI (p = 0.66) with reduced BMD and use of bisphosphonates. CONCLUSION: Liver transplant individuals using bisphosphonates present greater radiographic signs of bone sclerosis suggestive of a greater propensity to develop osteonecrosis of the jaw and an increased risk of presenting changes suggestive of reduced bone mineral density on panoramic radiographs when compared to liver transplant individuals not using bisphosphonates.

An imaging­based diagnostic approach to vascular anomalies of the oral and maxillofacial region.

The accurate diagnosis of vascular anomalies (VAs) is considered a challenging endeavor. Misdiagnosis of VAs can lead clinicians in the wrong direction, such as the performance of an unnecessary biopsy or inappropriate surgical procedures, which can potentially lead to unforeseen consequences and increase the risk of patient injury. The purpose of the present study was to develop an approach for the diagnosis of VAs of the oral and maxillofacial region based on computed tomography (CT), magnetic resonance imaging (MRI) and dynamic contrast-enhanced MRI (DCE-MRI). In the present study, the CT and MR images of 87 VAs were examined, and the following imaging features were evaluated: Detectability of the lesion, the periphery of the lesion, the inner nature of the lesion, the density of the lesion on CT, the signal intensity of the lesion on MRI, the detectability of phleboliths and the shape of the lesion. A total of 29 lesions were further evaluated using the contrast index (CI) curves created from the DCE-MRI images. A diagnostic diagram, which is based on the imaging features of VAs and CI curve patterns, was subsequently extrapolated. The results obtained demonstrated that the VAs were detected more readily by MRI compared with CT, whereas the detectability of phleboliths was superior when using CT compared with MRI. VAs showed a propensity for homogeneous isodensity on CT, whereas, by contrast, they exhibited a propensity for heterogeneous hyperdensity on CE-CT. VAs also showed a propensity for homogeneous intermediate signal intensity when performing T1-weighted imaging (T1WI), heterogeneous high signal intensity when performing short tau inversion recovery MRI, and heterogeneous high signal intensity when performing fat-saturated CE-T1WI. The CI curves of VAs were found to exhibit a specific pattern: Of the 29 CI curves, 23 (79.3%) showed early weak enhancement, followed by a plateau leading up to 400-600 sec. An imaging-based diagnostic diagram was ultimately formulated. This diagram can act as an aid for radiologists when they are expecting to find a VA, and hopefully serve the purpose of simplifying the diagnostic process. Taken together, the findings of the present study indicated that DCE-MRI may be considered a useful tool for the diagnosis of VAs.

Assessment of the correlation between mandibular radiomorphometric patterns and dual-energy X-ray absorptiometry measurements for screening bone mineral density.

The objective of this study was to investigate the correlation between scores for femoral and lumbar spine bone mineral density (dual-energy X-ray absorptiometry [DXA]) and visual, qualitative mandibular bone pattern assess¬ments (mandibular cortical index, trabecular bone pattern, and visual mandibular cortical width) as well as age and body mass index. Three trained observers evaluated 200 panoramic radiographs and 200 femoral and lumbar spine DXA measurements from 100 male and 100 female participants. The κ test showed an acceptable agreement among observers (0.73; P = 0.003). The Shapiro-Wilk test revealed that the variables were not normally distributed, so the Spearman correlation test was used. The mean age of the sample was 60.7 (13.9) years, and 86.0% of the patients were White. There were inverse correlations between the mandibular cortical index and the spine T-score in men, women, and the total sample as well as between the spine Z-score in the total sample. An inverse correlation was observed between the trabecular bone pattern and the spine T- and Z-scores in women and the total sample. The results also showed inverse correlations between the visual mandibular cortical width and all parameters analyzed in men, women, and the total sample except for the femur T-score and spine T- and Z-scores in men. Body mass index was correlated with all DXA parameters. Age was inversely correlated with femur T-scores in men and women but not with spine DXA values in men. The results suggest that qualitative assessments of radiomorphometric patterns on panoramic radiographs correlate with DXA values and therefore are suitable for screening patients at risk of developing low bone mineral density.

Maxillary sinus volumetric changes in jet aircraft pilots: A multislice computed tomography pilot study.

Purpose: This study evaluated maxillary sinus volume changes in military jet aircraft pilot candidates before and after the training program, in comparison with a control group, considering the effects of pressurization, altitude, and total flight hours, through multislice computed tomography. Materials and Methods: Fifteen fighter pilots were evaluated before initiating the training program and after the final approval. The control group consisted of 41 young adults who had not flown during their military career. The volumes of each maxillary sinus were measured individually before and at the end of the training program. Results: When comparing the initial and final volumes in the pilots, a statistically significant increase was observed both in the left and right maxillary sinuses. When evaluating the average total volume of the maxillary sinuses (i.e., the average volume of the right and left maxillary sinuses together), a significant increase in the volume of the maxillary sinuses was observed in the pilot group when compared to the control group. Conclusion: The maxillary sinus volumes in aircraft pilot candidates increased after the 8-month training program. This may be explained by changes in the gravitational force, the expansion of gas, and positive pressure from oxygen masks. This unprecedented investigation among pilots might lead to other investigations considering paranasal sinus alterations in this singular population.

The oral manifestations of Huntington's disease: A systematic review of prevalence.

OBJECTIVES: The objective of this systematic literature review was to provide a complete panorama of the oral manifestations of Huntington's disease (HD). MATERIALS AND METHODS: Databases were searched, and original research studies or case report manuscripts up to May 2021 were included using keywords that describe HD combined with words related to oral health; MeSH terms were used exclusively. No time or language restrictions were applied. RESULTS: Twenty-two investigations (12 original articles and 10 case reports) regarding oral manifestations of HD were included. The subjects examined in the selected research articles were dental health, coordination of oral structures, speech, dysphagia, and swallowing alterations. The case reports described dental treatment procedures, oromandibular dyskinesia, dysphagia, and speech alterations. CONCLUSIONS: The oral manifestations of HD were found to be associated with the advance of the disease in that the more severe the HD, the worse the alterations affecting the oral cavity. Dysphagia, dysarthria, masticatory problems, oral health impairment, and choreiform movements involving the tongue and other orofacial muscles were the main manifestations of HD in the oral cavity. The PROSPERO systematic review registration number of this study is CRD42021238934.

Assessment of mandibular cortical index in patients with hepatic cirrhosis: A case-control study.

AIMS: To assess the presence of alterations suggestive of reduced bone mineral density (BMD) by using mandibular cortical index (MCI) in panoramic radiographs of cirrhotic individuals and to evaluate their relationship with other characteristics of hepatic cirrhosis (HC). METHODS AND RESULTS: This is an observational case-control study assessing the medical records of 165 cirrhotic patients matched by sex and age with healthy individuals. MELD (model of end stage liver disease) score, etiology, complications, comorbidities, and serum levels of vitamin D were collected. MCI was used to obtain BMD. Binary logistic regression was used to test associations and the risk estimates were expressed in odds ratio. Most of the sample consisted of men (73.93%) with median age of 56 years old. In the study group, the mean value of MELD was 16.5 and hepatitis C was the main etiology of HC (33.9%). Cirrhotic individuals are 3.99 times more likely to present alterations suggestive of reduced BMD (p < .01). There was no statistical significance in the association of MCI with levels of vitamin D, comorbidities, etiology or cirrhosis complications. CONCLUSIONS: MCI suggestive of reduced BMD is more likely to be identified in panoramic radiographs of cirrhotic individuals than of healthy ones.

Diffusion-weighted magnetic resonance imaging of mandibular bone marrow: do apparent diffusion coefficient values of the cervical vertebrae and mandible correlate with age?

OBJECTIVES: The objective of this investigation was to assess the correlation between the mandible and cervical vertebrae bone marrow apparent diffusion coefficient (ADC), obtained by diffusion-weighted magnetic resonance imaging (DWI), with age; to verify the correlation between ADC values from the mandible and the cervical vertebrae; to describe and assess the differences between ADC values obtained from DWI examinations of distinct mandible areas as well as cervical vertebrae. METHODS: Thirty imaging examinations with DWI for that included the mandible and C1, C2, C3, and C4 vertebrae in the same examination were included. ADC values were collected from 7 distinct areas in the mandible and the cervical vertebrae. Differences between ADC values and non-parametric correlations were performed. RESULTS: A total of 270 regions were assessed. No significant difference was found between ADC values of all areas tested. An inverse correlation was found between C2, C3, and C4 vertebrae ADC values and age. The significant correlation of anatomic area ADC values and age were presented as graphics to verify if the linear trend of ADC values and age are in accordance with the literature CONCLUSIONS: The mandible area that most correlates with the cervical vertebrae, using ADC values, is the posterior trabecular area, below the inferior molars. Also, C2, C3, and C4 vertebrae ADC values inversely correlate with age, which demonstrates the bone qualitative changes in bone composition. ADC values may be useful for the qualitative assessment of bone quality to screen patients at osteoporosis risk.

Head and neck radiotherapy-induced changes in dentomaxillofacial structures detected on panoramic radiographs: A systematic review.

PURPOSE: This study aimed to summarize the impact of neck and head radiation treatment on maxillofacial structures detected on panoramic radiographs. MATERIALS AND METHODS: In this systematic review, the authors searched PubMed Central, Embase, Scopus, Cochrane Central Register of Controlled Trials, Web of Science, and Google Scholar for original research studies up to February 2020 that included the following Medical Subject Headings keywords: words related to "radiotherapy" and synonyms combined with keywords related to "panoramic radiography" and "oral diagnosis" and synonyms. Only original studies in English that investigated the maxillofacial effects of radiotherapy via panoramic radiographs were included. The quality of the selected manuscripts was evaluated by assessing the risk of bias using Cochrane's ROBINS-I tool for non-randomized studies. RESULTS: Thirty-three studies were eligible and included in this review. The main objectives pertained to the assessment of the effects of radiation on maxillofacial structures, including bone architecture alterations, periodontal space widening, teeth development abnormalities, osteoradionecrosis, and implant bone loss. The number of participants evaluated ranged from 8 to 176. CONCLUSION: The interaction between ionizing radiation and maxillofacial structures results in hazard to the tissues involved, particularly the bone tissue, periosteum, connective tissue of the mucosa, and endothelium. Hard tissue changes due to radiation therapy can be detected on panoramic radiographs.

Avaliação das características de lesões odontogênicas por meio da ressonância magnética de 3Teslas e tomografia computadorizada multislice / Assessment of odontogenic lesions imaging features in magnetic resonance imaging and multislice computed tomography

As lesões odontogênicas constituem achados relativamente frequentes na prática odontológica e são frequentemente investigadas inicialmente por meio de exames radiográficos bidimensionais. Todavia, tais exames apresentam limitações inerentes à sua técnica. Por conta disso, técnicas de imagem avançadas como a tomografia computadorizada multislice e a ressonância magnética podem e devem ser aplicadas para o estudo das lesões odontogênicas, otimizando hipóteses diagnósticas. Assim, o objetivo desta pesquisa foi estudar, por meio da ressonância magnética em imagens ponderadas em T1, STIR e difusão, e por meio da tomografia computadorizada multislice, considerando a escala de Hounsfield, os 3 tipos de lesões odontogênicas: o ameloblastoma, o queratocisto odontogênico e o cisto dentígero. O ameloblastoma também foi analisado considerando-se seus conteúdos internos (sólido e cístico) isoladamente. Para tal, foram estudadas retrospectivamente 71 imagens. Como resultado, observou-se que, por meio das imagens em ressonância magnética, especialmente ponderadas em STIR, foi possível a diferenciação do conteúdo sólido do ameloblastoma do seu próprio conteúdo cístico e do queratocisto odontogênico; e a diferenciação do conteúdo cístico do ameloblastoma do cisto dentígero. Ademais, os valores do coeficiente de difusão aparente são úteis na diferenciação dos conteúdos císticos entre os ameloblastomas de queratocistos odontogênicos e de cistos dentígeros. Por meio dos valores da escala de Hounsfield, foi possível a diferenciação dos ameloblastomas (considerando seus conteúdos sólidos e císticos em uma mesma análise) de cistos dentígeros e dos queratocistos odontogênicos. Os parâmetros analisados por meio destas técnicas avançadas de imagem possuem correspondência com os conteúdos internos das lesões estudadas, do ponto de vista histopatológico.

Imaging features of Stafne bone defects on computed tomography: An assessment of 40 cases.

PURPOSE: This study was performed to assess and describe the imaging features of 40 cases of Stafne bone defects (SBDs) on computed tomographic (CT) examinations. MATERIALS AND METHODS: This study collected data, including age and sex, from 40 patients with SBDs who underwent CT exams. The imaging features of the SBDs were assessed in terms of their location, average size, the relationship of their contour with the cortical plate of the lingual mandible, bone margins, degree of internal density, shape, topographic relationship between the defect and the mandibular edge, the distance from the SBD to the base of the mandible, and the Ariji classification (type I, II, and III). RESULTS: The average age was 57.3 years (range, 28-78 years), and the patients were predominantly male (70%). In all cases (100%), the posterior unilateral lingual SBD variant was observed. Within the Ariji classification, type I was the most common (60%). Among the most frequently observed radiographic characteristics were thick sclerotic bone margin across the entire defect contour, completely hypointense internal content, an oval shape, and continuity with the mandibular base with discontinuity of the mandibular edge. CONCLUSION: This study showed that posterior SBDs could present with an oval or rounded shape, complete hypodensity, and thick sclerotic margins. Likewise, SBDs could appear almost anywhere, with minor differences from the classic SBD appearance. It is fundamental for dental practitioners to know the imaging features of SBDs, since they are diagnosed primarily based on imaging.

Mandibular cortical index in the screening of postmenopausal at low mineral density risk: a systematic review.

OBJECTIVES: This systematic literature review addressed the use of mandibular cortical index (MCI), assessed by panoramic radiography, for the identification of postmenopausal women at risk of osteoporosis. METHODS: Databases were searched for original research studies published from September 2010 to September 2020 using the following keywords: "postmenopausal osteoporosis" and synonyms combined with "panoramic radiography" and synonyms. Only English language manuscripts and studies pertaining to the MCI were selected. RESULTS: A total of 24 studies were included. The publications were highly heterogeneous in terms of the subject of interest, i.e. the MCI, with some studies comparing the usefulness of the MCI using panoramic radiography and using cone beam computed tomography, and others comparing different radiomorphometric indexes developed for panoramic radiography. CONCLUSIONS: Based on the literature included in this systematic review, we conclude that the MCI is useful as an auxiliary tool for identifying postmenopausal females at risk of low bone mineral density (BMD), as it correlates with skeletal BMD measured by dual X-ray absorptiometry. Nevertheless, other radiomorphometric indexes obtained from panoramic radiographs, such as panoramic mandibular index, mental index, and mandibular cortical width, are also valuable as auxiliary tools in the identification of postmenopausal females at risk, as they also correlate with BMD. Thus, it is not possible to affirm which index is the most reliable for the identification of postmenopausal females considering the literature screened. PROSPERO registration systematic review CRD42020208152.

18F-NaF uptake in dentomaxillofacial bones as a result of oral alterations: a positron emission tomography/computerized tomography scanning study.

OBJECTIVES: 18F-NaF is a bone scanning radiotracer that reflects changes in bone metabolism, and it is applied in oncology to scan bone tumors or metastasis. Dentomaxillofacial alterations can lead to 18F-NaF uptake and could lead to false-positive results in PET/CT examinations. Hence, the objective of this research was to verify if the uptake of 18F-NaF in the mandible or maxilla is correlated to the presence of odontogenic alterations, which could lead to false-positive results in positron emission tomography/computerized tomography (PET/CT) examinations. METHODS: 42 patients who underwent 18F-NaF PET/CT examinations and panoramic radiographs to detect bone metastasis and to assess oral conditions before oncologic treatment were included. Edentulous patients and patients with neoplasms in the maxillofacial area, and those whose imaging examinations had technical failures were excluded from the study. RESULTS: A total of 252 areas from panoramic radiographs and PET/CT examinations were assessed. It was observed that the presence of periodontal bone loss resulted in a higher number of cases with false negatives. Accuracy, sensitivity, and specificity of 18F-NaF uptake-regardless of the type of odontogenic origin alteration-were 76.2%, 53.3%, and 89.4%, respectively. CONCLUSION: 18F-NaF uptake in the maxilla or mandible could be influenced by oral alterations in the alveolar bones. The alterations in the oral cavity that lead to 18F-NaF accumulation should be recognized by medical radiologists to prevent false-positive results in PET/CT examinations using the tracer 18F-NaF.

Maxillofacial manifestations of Proteus syndrome: a systematic review with a case report.

OBJECTIVES: Proteus syndrome (PS) is an extremely rare disorder with asymmetric and disproportionate bone overgrowth. Craniofacial abnormalities in PS are less frequent than skeletal abnormalities. Although there are recognized oral and maxillofacial manifestations of PS, few case reports describing these manifestations are available. Thus, the objective of this systematic review and case report is to describe oral and maxillofacial manifestations of PS and to report a PS case. METHODS: A 31-year-old male presented with restricted mouth opening and pain during mastication. A panoramic radiograph and an occlusal radiograph were obtained. Reports with relevant keywords were assessed. Data were summarized and demonstrated using a critical appraisal checklist for case reports. RESULTS: The panoramic radiograph demonstrated unilateral overgrowth of the mandible, impacted teeth, and deciduous prolonged retention. Thirteen PS case reports were identified. CONCLUSIONS: Proteus syndrome oral and maxillofacial manifestations may include dental agenesis, impacted teeth, malocclusion, asymmetric dental growth and maturation, frontal line displacement, asymmetric tongue enlargement, mandibular hemihypertrophy and asymmetry, presence of exostoses/hyperostosis, degenerative changes in the temporomandibular joint, alterations of maxillary and mandibular vertical and/or horizontal growth, and enlargement of mandibular canal and foramen. The PROSPERO systematic review registration number is CRD42019140942.

Assessment of Hounsfield unit in the differential diagnosis of odontogenic cysts.

OBJECTIVES: The purpose of this study was to evaluate the usefulness of Hounsfield unit (HU) assessment with multislice-CT in the differentiation of radicular cysts (RCs), dentigerous cysts (DCs) and odontogenic keratocysts (OKCs). METHODS: In total, 307 odontogenic cysts (RCs, DCs and OKCs) were included in this study. Cysts with lesion diameter <10 mm, cysts with artefacts affecting measurement of HU values, cysts involving infection and recurrent cysts were regarded as exclusion criteria. Images were acquired in three different types of CT scanners: Aquilion ONE, Discovery CT750 HD and SOMATOM Definition Flash. Differences in HU values among scanners and among types of odontogenic cysts were assessed using one-way analysis of variance; multiple comparisons were performed post hoc, using the Tukey-Kramer honestly significant difference test. RESULTS: In total, 164 cysts were analysed in this study (64 RCs, 57 DCs and 43 OKCs). Regardless of the type of lesion, the Aquilion ONE scanner demonstrated a significant difference in HU value, compared with the Discovery CT750 HD scanner. Regardless of CT scanner model, HU values significantly differed between DCs and OKCs (p < 0.0001), as well as between OKCs and RCs (p < 0.0001). CONCLUSIONS: HU values were found to vary among CT scanners and should always be associated with other lesion imaging features while interpreting and elaboration diagnostic hypothesis. Notably, the results suggested that OKCs might be able to be differentiated from DCs and RCs by using HU values.

Detection of calcified atheromas on panoramic radiographs of cirrhotic patients.

BACKGROUND: The present study aimed to investigate the prevalence of calcified atheromas in carotid arteries (CACA) on panoramic radiographs of patients with liver cirrhosis (LC). METHODS AND RESULTS: A case-control study of 67 individuals with LC (case group) and 67 healthy individuals (control group), matched by gender and age, was performed. In addition to demographic information, data on LC were also collected for the case group. Panoramic radiographs were evaluated by two previously calibrated examiners. The sample consisted predominantly of male individuals (n = 50; 74.62%), with mean age of 55 years old. In the case group, the mean value for the model of end-stage liver disease was 16, and the major aetiology of LC was alcoholism (n = 26; 38.8%). Thirteen (19.4%) LC patients had CACA, whereas only four (5.9%) healthy patients had this condition. LC patients are 3.72 times more likely to have CACA compared to healthy individuals (P = .02). The presence of nephropathies increases the risk of development of atheromas by 18.58 times in cirrhotic individuals (P = .04). CONCLUSIONS: Cirrhotic patients are more likely to have CACA compared to healthy patients, and this risk increases significantly when kidney disease is involved.

Do HIV patients have mandibular osteoporotic alterations? A mandibular cortical index case-control study / Pacientes com infecção por HIV tem alterações osteoporóticas na mandíbula? Um estudo caso controle utilizando o índice da cortical mandibular

Objective: The objective of this study was to evaluate mandibular osteoporotic alterations in patients with HIV infection in comparison to non-HIV-infected patients using panoramic radiographs. Material and Methods: 26 HIV-infected patients and 142 non-HIV-infected patients (control group) were included in this study. Panoramic radiographs of the participants were assessed considering mandibular cortical index (MCI). Non-parametric comparisons between groups were performed, using Mann-Whitney test, at a level significance level of p= 0.05. Results: HIV-infected patients presented lower bone mineral density (BMD) at mandible, assessed by MCI in panoramic radiographs when compared to non-HIV-infected patients. The medication intake of HIV-infected patients was highly heterogeneous and could not be associated to the low BMD presented in the mandibular cortex. Conclusions: HIV-infected patients may present lower mandibular BMD than non-HIV-infected patients. (AU)

Objetivo: O objetivo deste estudo foi avaliar as alterações osteoporóticas mandibulares em pacientes com infecção por HIV comparando-os com pacientes não infectados, por meio de radiografias panorâmicas. Material e Métodos: 26 pacientes infectados pelo HIV e 142 pacientes não infectados (grupo controle) foram incluídos neste estudo. As radiografias panorâmicas dos participantes foram avaliadas considerando o índice da cortical mandibular (MCI). Comparações não paramétricas entre os grupos foram realizadas, com o teste de Mann-Whitney e nível de significância de p = 0,05. Resultados: Pacientes infectados pelo HIV apresentaram menor densidade mineral óssea (BMD) na mandíbula, avaliada pelo MCI em radiografias panorâmicas, quando comparados aos pacientes não infectados pelo HIV. A ingestão de medicamentos de pacientes infectados pelo HIV foi altamente heterogênea e não pôde ser associada à baixa BMD apresentada no córtex mandibular. Conclusões: Pacientes infectados pelo HIV podem apresentar BMD mandibular menor do que pacientes não infectados pelo HIV. (AU)

Bone mineral density and mandibular osteoporotic alterations in panoramic radiographs: Correlation by peripheral bone densitometry in men.

AIM: Mandibular cortical index has proven to be inversely correlated to bone densitometry; however, trabecular bone pattern has not been widely studied. Thus, the main objectives of this study were: (1) to analyze the correlations between three different sites of peripheral dual-energy X-ray absorptiometry with the mandibular cortical index and the trabecular bone pattern classification; (2) to assess the correlation between the mandibular cortical index and the trabecular bone pattern; (3) to evaluate the diagnostic accuracy of the mandibular cortical index and the trabecular bone pattern using panoramic radiographs in a sample of Brazilian men. Additionally, peripheral dual-energy X-ray absorptiometry findings in men were described. MATERIALS AND METHODS: There are about 44 men who had previously undergone panoramic radiography and bone densitometry were evaluated. Mandibular cortical index and trabecular bone pattern classifications were performed. The median T-scores of the men were analyzed. Spearman's test was performed to assess correlations. RESULTS: An inverse correlation was found between mandibular cortical index and proximal bone densitometry site. No correlation was found between mandibular cortical index and trabecular bone pattern or between peripheral densitometry and trabecular bone pattern. Greater accuracy was observed in mandibular cortical index when compared to trabecular bone pattern. Mandibular cortical index evaluations by panoramic radiographs are a useful screening tool for low bone mineral density, but trabecular bone pattern cannot be applied to screen patients for osteoporosis risk. Mandibular cortical index has an inverse correlation with proximal sites of forearm densitometry.

Comparison between different cone-beam computed tomography devices in the detection of mechanically simulated peri-implant bone defects.

PURPOSE: This study compared 2 cone-beam computed tomography (CBCT) systems in the detection of mechanically simulated peri-implant buccal bone defects in dry human mandibles. MATERIALS AND METHODS: Twenty-four implants were placed in 7 dry human mandibles. Peri-implant bone defects were created in the buccal plates of 16 implants using spherical burs. All mandibles were scanned using 2 CBCT systems with their commonly used acquisition protocols: i-CAT Gendex CB-500 (Imaging Sciences, Hatfield, PA, USA; field of view [FOV], 8 cm×8 cm; voxel size, 0.125 mm; 120 kVp; 5 mA; 23 s) and Orthopantomograph OP300 (Intrumentarium, Tuusula, Finland; FOV, 6 cm×8 cm; voxel size, 0.085 mm; 90 kVp; 6.3 mA; 13 s). Two oral and maxillofacial radiologists assessed the CBCT images for the presence of a defect and measured the depth of the bone defects. Diagnostic performance was compared in terms of the area under the curve (AUC), accuracy, sensitivity, specificity, and intraclass correlation coefficient. RESULTS: High intraobserver and interobserver agreement was found (P<0.05). The OP300 showed slightly better diagnostic performance and higher detection rates than the CB-500 (AUC, 0.56±0.03), with a mean accuracy of 75.0%, sensitivity of 81.2%, and specificity of 62.5%. Higher contrast was observed with the CB-500, whereas the OP300 formed more artifacts. CONCLUSION: Within the limitations of this study, the present results suggest that the choice of CBCT systems with their respective commonly used acquisition protocols does not significantly affect diagnostic performance in detecting and measuring buccal peri-implant bone loss.