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PURPOSE: The purpose of this study was to investigate appropriate contrast reference values (CRVs) by comparing the contrast in phantom and clinical images. MATERIALS AND METHODS: Phantom contrast was measured using two methods: (1) counting the number of visible pits of different depths in an aluminum plate, and (2) obtaining the contrast-to-noise ratio (CNR) for 5 tissue-equivalent materials (porcelain, aluminum, polytetrafluoroethylene [PTFE], polyoxymethylene [POM], and polymethylmethacrylate [PMMA]). Four panoramic radiographs of the contrast phantom, embedded in the 4 different regions of the arch-form stand, and 1 real skull phantom image were obtained, post-processed, and compared. The clinical image quality evaluation chart was used to obtain the cut-off values of the phantom CRV corresponding to the criterion of being adequate for diagnosis. RESULTS: The CRVs were obtained using 4 aluminum pits in the incisor and premolar region, 5 aluminum pits in the molar region, and 2 aluminum pits in the temporomandibular joint (TMJ) region. The CRVs obtained based on the CNR measured in the anterior region were: porcelain, 13.95; aluminum, 9.68; PTFE, 6.71; and POM, 1.79. The corresponding values in the premolar region were: porcelain, 14.22; aluminum, 8.82; PTFE, 5.95; and POM, 2.30. In the molar region, the following values were obtained: porcelain, 7.40; aluminum, 3.68; PTFE, 1.27; and POM, - 0.18. The CRVs for the TMJ region were: porcelain, 3.60; aluminum, 2.04; PTFE, 0.48; and POM, - 0.43. CONCLUSION: CRVs were determined for each part of the jaw using the CNR value and the number of pits observed in phantom images.
Assuntos
Alumínio , Dente Pré-Molar , Porcelana Dentária , Diagnóstico , Incisivo , Arcada Osseodentária , Dente Molar , Imagens de Fantasmas , Polimetil Metacrilato , Politetrafluoretileno , Garantia da Qualidade dos Cuidados de Saúde , Radiografia Panorâmica , Valores de Referência , Crânio , Articulação TemporomandibularRESUMO
PURPOSE: This study was performed to evaluate condylar surface changes and remodeling after orthognathic surgery using three-dimensional computed tomography (3D CT) imaging, including comparisons between the right and left sides and between the sexes. MATERIALS AND METHODS: Forty patients (20 males and 20 females) who underwent multi-detector CT examinations before and after surgery were selected. Three-dimensional images comprising thousands of points on the condylar surface were obtained before and after surgery. For the quantitative assessment of condylar surface changes, point-to-point (preoperative-to-postoperative) distances were calculated using D processing software. These point-to-point distances were converted to a color map. In order to evaluate the types of condylar remodeling, the condylar head was divided into six areas (anteromedial, anteromiddle, anterolateral, posteromedial, posteromiddle, and posterolateral areas) and each area was classified into three types of condylar remodeling (bone formation, no change, and bone resorption) based on the color map. Additionally, comparative analyses were performed between the right and left sides and according to sex. RESULTS: The mean of the average point-to-point distances on condylar surface was 0.11±0.03 mm. Bone resorption occurred more frequently than other types of condylar remodeling, especially in the lateral areas. However, bone formation in the anteromedial area was particularly prominent. No significant difference was found between the right and left condyles, but condylar surface changes in males were significantly larger than in females. CONCLUSION: This study revealed that condylar remodeling exhibited a tendency towards bone resorption, especially in the lateral areas. Condylar surface changes occurred, but were small.
Assuntos
Feminino , Humanos , Masculino , Remodelação Óssea , Reabsorção Óssea , Cabeça , Imageamento Tridimensional , Côndilo Mandibular , Tomografia Computadorizada Multidetectores , Cirurgia Ortognática , OsteogêneseRESUMO
In published article by Li et al., an author's name was misspelled.
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PURPOSE: This study was performed to analyze human maxillary and mandibular trabecular bone using the data acquired from micro-computed tomography (micro-CT), and to characterize the site-specific microstructures of trabeculae. MATERIALS AND METHODS: Sixty-nine cylindrical bone specimens were prepared from the mandible and maxilla. They were divided into 5 groups by region: the anterior maxilla, posterior maxilla, anterior mandible, posterior mandible, and mandibular condyle. After the specimens were scanned using a micro-CT system, three-dimensional microstructural parameters such as the percent bone volume, bone specific surface, trabecular thickness, trabecular separation, trabecular number, structure model index, and degrees of anisotropy were analyzed. RESULTS: Among the regions other than the condylar area, the anterior mandibular region showed the highest trabecular thickness and the lowest value for the bone specific surface. On the other hand, the posterior maxilla region showed the lowest trabecular thickness and the highest value for the bone specific surface. The degree of anisotropy was lowest at the anterior mandible. The condyle showed thinner trabeculae with a more anisotropic arrangement than the other mandibular regions. CONCLUSION: There were microstructural differences between the regions of the maxilla and mandible. These results suggested that different mechanisms of external force might exist at each site.
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Humanos , Anisotropia , Mãos , Imageamento Tridimensional , Arcada Osseodentária , Mandíbula , Côndilo Mandibular , MaxilaRESUMO
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Antibacterianos , Medula Óssea , Sistemas de Liberação de Medicamentos , Inflamação , Isquemia , Mandíbula , Necrose , Osteomielite , Oxigênio , Plasma , Polimetil MetacrilatoRESUMO
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Bochecha , Ossos Faciais , Displasia Fibrosa Poliostótica , Direitos do Paciente , Maleabilidade , Esqueleto , ZigomaRESUMO
Synovial sarcoma (SS) is a malignant soft tissue tumor comprising 5-10% of all soft tissue sarcomas. This tumor normally occurs in the paraarticular regions of the extremities but is rare in head and neck sites. SS is sometimes difficult to diagnose because it can mimic benign lesions both clinically and radiologically. This paper presents a rare case of a SS of the buccal space of a 25-year old man. The histology examination and immunohistochemistry of the mass led to a diagnosis of synovial sarcoma. The patient was treated primarily with a surgical resection, followed by radiotherapy and chemotherapy. The follow up examination 17-months after surgery showed no signs of tumor relapse or metastasis.
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Humanos , Extremidades , Seguimentos , Cabeça , Neoplasias de Cabeça e Pescoço , Hidrazinas , Imuno-Histoquímica , Pescoço , Metástase Neoplásica , Recidiva , Sarcoma , Sarcoma SinovialRESUMO
Thermally induced bone necrosis during implant surgery is a rare phenomenon and a potential contributing factor to implant failure. The frictional heat generated at the time of surgery causes a certain degree of necrosis of the surrounding differentiated and undifferentiated cells. The bone necrosis occurred in the mandible in all three cases, leading to a soft tissue lesion and pain. In each case, radiolucent areas appeared in the middle and apical portions of the implant 4 weeks after surgery. Thermally induced bone necrosis did not improve following systemic antibiotic medication, necessitating surgical treatment. The nonintegrated implants were removed, and meticulous debridement of dead bone and granulation tissue was performed. Then, new implants were implanted along with the placement of autogenous and xenogenic bone covered with a collagen membrane. No further complications occurred after re-operation. The radiolucencies around the new implants gradually resolved entirely, and the soft tissue lesions healed successfully. At 4-5 months after reoperation, implant loading was initiated and the implant-supported restorations have been functioning. The aim of this case report is to present the successful clinical treatment of three cases suspected to be caused by thermally induced bone necrosis after implant drilling.
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Colágeno , Desbridamento , Implantes Dentários , Fricção , Tecido de Granulação , Temperatura Alta , Mandíbula , Mandrillus , Membranas , Necrose , Osteonecrose , ReoperaçãoRESUMO
Bisphosphonates are widely used to treat osteoporosis, hypercalcemia of malignant tumor. Despite their clinical benefit, bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a newly documented complication to patients receiving these drugs and first recognized by Marx in 2003. Thus, consideration of prevention and needs regarding unequivocal treatment regimen have emerged. Recently, several authors emphasized reports on appropriate clinical availability of surgical approach. It serves to concern about guideline for surgical and conservative treatment modalities. So, it is the purpose of this paper to review the current literatures about treatment regimens of BRONJ.
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Humanos , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Difosfonatos , Hipercalcemia , Osteonecrose , OsteoporoseRESUMO
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Idoso de 80 Anos ou mais , Feminino , Humanos , Bandagens , Densidade Óssea , Remodelação Óssea , Bochecha , Difosfonatos , Hipercalcemia , Arcada Osseodentária , Dente Molar , Necrose , Metástase Neoplásica , Osteonecrose , Osteoporose , Osteoporose Pós-Menopausa , Supuração , Cirurgia Bucal , Dente , Extração DentáriaRESUMO
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Feminino , Humanos , Masculino , Ingestão de Alimentos , Ductos Salivares , Cálculos das Glândulas Salivares , Glândulas Salivares , Glândula SubmandibularRESUMO
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Feminino , Humanos , Dente Pré-Molar , Dor Crônica , Anormalidades Congênitas , Cárie Dentária , Cabeça , Hemangiossarcoma , Oxigenoterapia Hiperbárica , Incidência , Dente Molar , Mucosite , Pescoço , Necrose , Osteorradionecrose , Porfirinas , Próteses e Implantes , Suturas , Língua , XerostomiaRESUMO
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Humanos , Pessoa de Meia-Idade , Bochecha , Incidência , Boca , Pleura , Tumores Fibrosos SolitáriosRESUMO
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Feminino , Humanos , Masculino , Distribuição por Idade , Emergências , Serviços Médicos de Emergência , Ossos Faciais , Hemorragia , Fraturas Maxilomandibulares , Pulpite , Estudos Retrospectivos , Lesões dos Tecidos Moles , Cirurgia Bucal , Transtornos da Articulação Temporomandibular , Traumatismos DentáriosRESUMO
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Feminino , Humanos , Angiomioma , Leiomioma , Extremidade Inferior , Boca , Músculo Liso Vascular , Tumor de Músculo Liso , Tela SubcutâneaRESUMO
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Humanos , Síndrome do Nevo Basocelular , Diagnóstico Precoce , Hipertelorismo , Cistos Odontogênicos , PenetrânciaRESUMO
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Feminino , Humanos , Ameloblastoma , Cisto Dentígero , Compostos de Amônio Quaternário , RecidivaRESUMO
Cholesterol granuloma is an unusual clinical entity described as an inflammatory granulation in response to the deposit of cholesterol crystals. It can develop in any portion of air cells within the temporal bone as a result of a lack of aeration and inadequate drainage, especially in the middle ear cavity. Here, we report very unusual three cases of cholesterol granuloma developed in mandible. In the first case a 68-year-old male with a large mass arising from the mandible was observed. Panoramic radiograph and computed tomography scans revealed a huge expanding lesion in the mandible. In the second case a 47-year-old female with a cystic lesion in the mandible was observed. And in the third case a 19-year-old male complaining atypical facial pain had a large lesion in the mandibular ramus. The histopathologic examinations of the cases showed numerous cholesterol crystals surrounded by ultinucleated foreign body giant cells.
