Knowledge and Attitudes of Primary Health Care Dentists Regarding Oral Cancer in Brazil.

OBJECTIVE: The aim of this study was to evaluate the knowledge and attitudes of dentists working in Primary Health Care Units from a Brazilian city, regarding oral cancer. MATERIALS AND METHODS: A prospective, cross-sectional, epidemiologic survey was performed. Seventy-one dentists from Primary Health Care Units were contacted at their workplace, and participated of the study. Data were collected through a self-administered questionnaire of 31 multiple-choice questions addressing the main clinical features and risk factors for oral cancer. The questionnaire was divided into two sections: questions related to general data and self-perception of the participants regarding personal knowledge of oral cancer, and objective questions related to general information on oral cancer (clinical features, characteristics, traits, and risk factors). The data were tabulated and analyzed by descriptive statistics. RESULTS: Participants were mostly females (81.5%), less than 40 years of age (57.7%), who underwent training 10-20 years ago (47.9%). Most respondents (66.2%) considered their level of knowledge about oral cancer to be satisfactory. However, only 26.8% of tem felt that they were able to carry out diagnostic procedures for oral cancer. Most of them (95.8%) were interested in participating in training courses on Oral Diagnostics; 56.3% of them reported not having received any training or guidance on how to conduct an examination to detect oral cancer during undergraduate training. CONCLUSIONS: These findings are consistent with previous reports and point to the need for new public policies to enable early diagnosis of oral cancer and a review of training in Oral Diagnostics in dental schools.

Cemento-Osseous Dysplasias: Imaging Features Based on Cone Beam Computed Tomography Scans

Abstract Imaging exams have important role in diagnosis of cemento-osseous dysplasia (COD). Cone beam computed tomography (CBCT) stands out for allowing three-dimensional image evaluation. This study aimed to assess the prevalence of cases diagnosed as COD on CBCT scans, as well identify the main imaging features related to these lesions. An analysis was performed in a database containing 22,400 radiological reports, in which all cases showing some type of COD were initially selected. These CBCT exams were reevaluated to confirm the radiographic diagnosis and determine the prevalence and distribution of the types of COD with regard to gender, age and preferred location, while describing its most common imaging aspects. Data were presented using descriptive analyses. There were 82 cases diagnosed as COD in the CBCT images (prevalence of 0.4%). The distribution of patients was 11 (13.4%) male and 71 (86.6%) female, with a mean age of 49.8 years (age-range 17-85 years). There were 47 (57.3%) cases of periapical COD, 23 (28%) of focal COD and 12 (14.6%) of florid COD. The mandible was more affected than the maxilla. In most cases, the lesions were mixed or hyperdense. All COD had well-defined limits and there were no cases of tooth displacement. In conclusion, periapical COD was the most common type and the most affected bone was the mandible. Imaging evaluation is critical for diagnosis and dentists should bear in mind all possible radiographic presentations of COD in order to prevent misleading diagnoses and consequently, inadequate treatments.

Resumo Os exames por imagem têm papel importante no diagnóstico da displasia cemento-óssea (DCO). A tomografia computadorizada por feixe cônico (TCFC) se destaca por permitir a avaliação tridimensional da imagem. O objetivo neste estudo foi avaliar a prevalência de casos diagnosticados como DCO nos exames de TCFC, bem como identificar as principais características de imagem relacionadas a essas lesões. Uma análise foi realizada em um banco de dados contendo 22.400 laudos radiológicos, no qual todos os casos que apresentavam algum tipo de DCO foram inicialmente selecionados. Estes exames foram reavaliados para confirmar o diagnóstico radiográfico e determinar a prevalência e distribuição dos tipos de DCO em relação ao sexo, idade e localização preferencial, além de descrever seus aspectos imaginológicos mais comuns. Os dados foram apresentados por meio de análise descritiva. Oitenta e dois casos foram diagnosticados como DCO nas imagens de TCFC (prevalência de 0,4%). A distribuição dos pacientes foi de 11 (13,4%) homens e 71 (86,6%) mulheres, com idade média de 49,8 anos (faixa etária de 17 a 85 anos). Houve 47 (57,3%) casos de DCO periapical, 23 (28%) de DCO focal e 12 (14,6%) de DCO florida. A mandíbula foi mais afetada que a maxila. Na maioria dos casos, as lesões foram mistas ou hiperdensas. Todas as DCO apresentaram limites bem definidos e não houve casos de deslocamento dentário. Em conclusão, a DCO periapical foi o tipo mais comum e o osso mais afetado foi a mandíbula. A avaliação da imagem é crítica para o seu diagnóstico e os dentistas devem ter em mente todas as possíveis apresentações radiográficas da DCO, a fim de prevenir diagnósticos enganosos e, conseqüentemente, tratamentos inadequados.

Cemento-Osseous Dysplasias: Imaging Features Based on Cone Beam Computed Tomography Scans.

Imaging exams have important role in diagnosis of cemento-osseous dysplasia (COD). Cone beam computed tomography (CBCT) stands out for allowing three-dimensional image evaluation. This study aimed to assess the prevalence of cases diagnosed as COD on CBCT scans, as well identify the main imaging features related to these lesions. An analysis was performed in a database containing 22,400 radiological reports, in which all cases showing some type of COD were initially selected. These CBCT exams were reevaluated to confirm the radiographic diagnosis and determine the prevalence and distribution of the types of COD with regard to gender, age and preferred location, while describing its most common imaging aspects. Data were presented using descriptive analyses. There were 82 cases diagnosed as COD in the CBCT images (prevalence of 0.4%). The distribution of patients was 11 (13.4%) male and 71 (86.6%) female, with a mean age of 49.8 years (age-range 17-85 years). There were 47 (57.3%) cases of periapical COD, 23 (28%) of focal COD and 12 (14.6%) of florid COD. The mandible was more affected than the maxilla. In most cases, the lesions were mixed or hyperdense. All COD had well-defined limits and there were no cases of tooth displacement. In conclusion, periapical COD was the most common type and the most affected bone was the mandible. Imaging evaluation is critical for diagnosis and dentists should bear in mind all possible radiographic presentations of COD in order to prevent misleading diagnoses and consequently, inadequate treatments.

Odontogenic keratocyst: The role of the orthodontist in the diagnosis of initial lesions.

Odontogenic keratocysts (OKCs) are locally infiltrative odontogenic cysts that are usually diagnosed during routine radiographic examinations. Therefore, it is critical that dental practitioners, in particular orthodontists, recognize and diagnose OKCs to recommend appropriate treatment. This report describes a patient whose OKC was not initially identified during orthodontic pretreatment. In addition, this report discusses the clinical and radiographic features of OKCs, as well as the differential diagnoses of these lesions.

Effects of Zoledronic Acid in Experimental Periapical Lesions in Rats: An Imaging and Histological Analysis

Abstract The aim of this study was to assess the imaging and histological features of experimental periapical lesions, including the adjacent alveolar bone, in rats under zoledronic acid treatment. The study used 40 male Wistar rats distributed into 8 groups of 5 animals each: G1: induction of periapical lesion (PL) and weekly intraperitoneal administration (WIPA) of saline solution (0.9% NaCl) for 4 weeks; G2: PL induction and WIPA of zoledronic acid (0.15 mg/kg/week) for 4 weeks; G3: PL induction and WIPA of saline solution for 8 weeks; G4: PL induction and WIPA of zoledronic acid for 8 weeks; G5:WIPA of saline solution for 4 weeks and subsequent PL induction; G6: WIPA of zoledronic acid for 4 weeks and subsequent PL induction; G7: WIPA of saline solution for 8 weeks and subsequent PL induction; G8: WIPA of zoledronic acid for 8 weeks and subsequent PL induction. The administration of zoledronic acid or saline solution continued after PL induction until the euthanasia. Thus, cone beam computed tomography and histological analysis were performed. Statistical analyzes were performed by ANOVA and Kruskal-Wallis test. Groups treated with zoledronic acid showed significantly smaller size of PL than the groups treated with 0.9% NaCl (p<0.05). PLs were formed by chronic inflammation ranging from mild to moderate, with no difference between groups. In all specimens, no mandibular necrosis was observed. In conclusion, the presence of PLs apparently does not represent an important risk factor for the development of bisphosphonate-related osteonecrosis of the jaws.

Resumo O objetivo deste estudo foi avaliar as características histológicas e de imagem de lesões periapicais experimentais, incluindo o osso alveolar adjacente, em ratos sob tratamento com ácido zoledrônico. O estudo utilizou 40 ratos Wistar, machos, distribuídos em 8 grupos de animais cada: G1: indução de lesão periapical (LP) e administração intraperitoneal semanal (AIS) de solução salina (NaCl 0.9%) por 4 semanas; G2: indução de LP e AIS de ácido zoledrônico (0,15 mg/kg/week) por 4 semanas; G3: indução de LP e AIS de solução salina por 8 semanas; G4: indução de LP e AIS de ácido zoledrônico por 8 semanas; G5- AIS de solução salina por 4 semanas e subsequente indução de LP; G6- AIS de ácido zoledrônico por 4 semanas e subsequente indução de LP; G7: AIS de solução salina por 8 semanas e subsequente indução de LP; G8: AIS de ácido zoledrônico por 8 semanas e subsequente indução de LP. A administração de ácido zoledrônico ou solução salina continuou após indução de LP até a eutanásia. Após isso, tomografia computadorizada de feixe cônico e análise histológica foram realizadas. Análises estatísticas foram realizadas por ANOVA e teste de Kruskal-Wallis. Os grupos tratados com ácido zoledrônico mostraram LPs significativamente menores que os grupos tratados com NaCl 0.9% (p <0.05). LPs eram formadas por inflamação crônica variando de leve a moderada, sem diferença entre os grupos. Em todos os espécimes, necrose mandibular não foi observada. Em conclusão, a presença de LPs aparentemente não representa um fator de risco importante para o desenvolvimento de osteonecrose relacionada ao uso de bisfosfonatos.

Mandibular destructive radiolucent lesion: The first sign of multiple myeloma.

The occurrence of a mandibular lesion as the first sign of multiple myeloma (MM) is uncommon. This report describes a case of MM diagnosed because of a mandibular lesion. A 62-year-old woman presented a destructive radiolucent lesion in the right mandibular ramus. The lesion caused rupture of the anterior cortical bone and extended from the retromolar area to the coronoid process. An incisional biopsy was performed. Histopathological examination revealed numerous pleomorphic plasma cells, some with binucleated nuclei. The tumor cells showed kappa light-chain restriction. Bone marrow biopsy showed findings of massive infiltration of neoplastic plasma cells, besides lesions in the vertebrae. The diagnosis of MM was established. The patient underwent autologous hematopoietic stem-cell transplantation. Currently, the patient is under regular follow up after 40 months of initial treatment. In conclusion, MM should be considered in the differential diagnosis of destructive mandibular lesions. Key words:Mandible, multiple myeloma, radiolucent lesion.

Evaluation of temporomandibular joint disk displacement and its correlation with pain and osseous abnormalities in symptomatic young patients with magnetic resonance imaging.

OBJECTIVE: To evaluate the occurrence of temporomandibular joint disk displacement and its correlation with pain and osseous abnormalities using magnetic resonance imaging (MRI) in patients under 21 years of age. STUDY DESIGN: MRI images in open- and closed-mouth positions from 102 patients, under 21 years of age (mean age 17 years), were studied retrospectively. Patients were divided into six groups according to the disk-condyle relationship. Chi-square, Marascuilo procedure, and Cochran-Mantel-Haenszel tests were used to evaluate the relationships among pain, abnormalities, and the groups. RESULTS: There was a statistically significant correlation between bilateral disk displacement without reduction and pain (P = .011), and osseous changes (P < .0001). There was no proven link between pain and osseous abnormality (P = .414). CONCLUSION: Young patients are susceptible to all stages of disk displacement. There was a strong correlation only between each variable (osseous abnormalities and pain) and the most severe stage of disk displacement (bilateral disk displacement without reduction).

Mixed periapical lesion: an atypical radicular cyst with extensive calcifications.

The radicular cyst is an inflammatory odontogenic cyst of endodontic origin. Radiographically, the lesion appears as a periapical radiolucent image. This report describes a very rare case of a mixed periapical radiographic image diagnosed as a radicular cyst. A 37-year-old female patient presented a mixed, well-circumscribed image located in the periapical region of the left maxillary central incisor, which presented unsatisfactory endodontic treatment. Microscopic examination revealed a cavity lined by non-keratinized squamous epithelium and extensive calcifications in the cystic lumen and lining epithelium. Diagnosis of radicular cyst with extensive calcifications was established. Endodontic retreatment was performed and no radiographic signs of recurrence were observed 18 months after treatment. Although very rare, a radicular cyst should be considered in the differential diagnosis of a mixed periapical image associated to teeth with pulp necrosis.

Mixed Periapical Lesion: An Atypical Radicular Cyst with Extensive Calcifications

The radicular cyst is an inflammatory odontogenic cyst of endodontic origin. Radiographically, the lesion appears as a periapical radiolucent image. This report describes a very rare case of a mixed periapical radiographic image diagnosed as a radicular cyst. A 37-year-old female patient presented a mixed, well-circumscribed image located in the periapical region of the left maxillary central incisor, which presented unsatisfactory endodontic treatment. Microscopic examination revealed a cavity lined by non-keratinized squamous epithelium and extensive calcifications in the cystic lumen and lining epithelium. Diagnosis of radicular cyst with extensive calcifications was established. Endodontic retreatment was performed and no radiographic signs of recurrence were observed 18 months after treatment. Although very rare, a radicular cyst should be considered in the differential diagnosis of a mixed periapical image associated to teeth with pulp necrosis.

O cisto radicular é um cisto odontogênico inflamatório de origem endodôntica. Radiograficamente, a lesão se apresenta como uma imagem radiolúcida periapical. Este relato descreve um caso muito raro de uma imagem radiográfica periapical mista diagnosticada como cisto radicular. Uma paciente de 37 anos de idade, do gênero feminino, apresentava uma imagem mista, bem circunscrita, localizada na região periapical do incisivo central superior esquerdo, que apresentava tratamento endodôntico insatisfatório. Avaliação microscópica revelou uma cavidade revestida por epitélio escamoso não-queratinizado e calcificações extensas na cavidade cística e revestimento epitelial. O diagnóstico de cisto radicular com extensas calcificações foi estabelecido. Retratamento endodôntico foi realizado e não foram observados sinais radiográficos de recorrência da lesão após 18 meses de tratamento. Embora muito raro, um cisto radicular deve ser considerado no diagnóstico diferencial de uma imagem periapical mista associada a dentes com necrose pulpar.

Ameloblastic fibroma: A rare case appearing as a mixed radiographic image.

Ameloblastic fibroma (AF) is a benign tumor of mixed odontogenic origin, which affects predominantly young individuals. AF appearing as a mixed radiographic image is very rare. This report describes a case of AF in a 12-year-old male identified during a routine radiographic exam for orthodontic treatment planning. The panoramic radiography revealed a well-defined multilocular mixed image located in the mandible between the roots of the left mandibular second premolar and first molar. The lesion was excised under local anesthesia. Histopathological analysis revealed islands of epithelial cells and columnar peripheral cells showing a nucleus in inverted polarization, interspersed with spindle-shaped cells and abundant extracellular matrix deposition. No atypia was observed. The diagnosis of AF was established. No tumor recurred up to 30 months after treatment. Although rare, AF should be also considered in the differential diagnosis of mixed radiographic images of the jaws in young patients. Key words:Ameloblastic fibroma, differential diagnosis, incidental finding, mixed image, radiographic features.

Evaluation of condyle defects using different reconstruction protocols of cone-beam computed tomography

This study was conducted to investigate how well cone-beam computed tomography (CBCT) can detect simulated cavitary defects in condyles, and to test the influence of the reconstruction protocols. Defects were created with spherical diamond burs (numbers 1013, 1016, 3017) in superior and/or posterior surfaces of twenty condyles. The condyles were scanned, and cross-sectional reconstructions were performed with nine different protocols, based on slice thickness (0.2, 0.6, 1.0 mm) and on the filters (original image, Sharpen Mild, S9) used. Two observers evaluated the defects, determining their presence and location. Statistical analysis was carried out using simple Kappa coefficient and McNemar's test to check inter- and intra-rater reliability. The chi-square test was used to compare the rater accuracy. Analysis of variance (Tukey's test) assessed the effect of the protocols used. Kappa values for inter- and intra-rater reliability demonstrate almost perfect agreement. The proportion of correct answers was significantly higher than that of errors for cavitary defects on both condyle surfaces (p < 0.01). Only in identifying the defects located on the posterior surface was it possible to observe the influence of the 1.0 mm protocol thickness and no filter, which showed a significantly lower value. Based on the results of the current study, the technique used was valid for identifying the existence of cavities in the condyle surface. However, the protocol of a 1.0 mm-thick slice and no filter proved to be the worst method for identifying the defects on the posterior surface.

Ossifying Fibroma of the Jaws: A Clinicopathological Case Series Study

The aim of this study was to assess the clinical, radiographic and microscopic features of a case series of ossifying fibroma (OF) of the jaws. For the study, all cases with OF diagnosis from the files of the Oral Pathology Laboratory, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil, were reviewed. Clinical data were obtained from the patient files and the radiographic features were evaluated in each case. All cases were reviewed microscopically to confirm the diagnosis. Eight cases were identified, 5 in females and 3 in males. The mean age of the patients was 33.7 years and most lesions (7 cases) occurred in the mandible. Radiographically, all lesions appeared as unilocular images and most of them (5 cases) were of mixed type. The mean size of the tumor was 3.1 cm and 3 cases caused displacement of the involved teeth. Microscopically, all cases showed several bone-like mineralized areas, immersed in the cellular connective tissue. From the 8 cases, 5 underwent surgical excision and 1 patient refused treatment. In the remaining 2 cases, this information was not available. In conclusion, OF occurs more commonly in women in the fourth decade of life, frequently as a mixed radiographic image in the mandible. Coherent differential diagnoses are important to guide the most adequate clinical approach. A correlation between clinical, imaginological and histopathological features is the key to establish the correct diagnosis.

O objetivo deste estudo foi analisar as características clínico-radiográficas e microscópicas de uma série de casos de fibroma ossificante (FO). Para o estudo, todos os casos com diagnóstico de FO do arquivo do Laboratório de Patologia Bucal da Universidade de Ribeirão Preto, Ribeirão Preto, São Paulo, Brasil, foram estudados. Os dados clínicos foram coletados das fichas de encaminhamento das lesões ao Laboratório. As características radiográficas foram avaliadas em cada caso. Todos os casos foram revisados microscopicamente para confirmação do diagnóstico. Oito casos foram identificados, 5 em mulheres e 3 em homens. A idade média dos pacientes foi de 33,7 anos e a maioria das lesões (7 casos) ocorreu na mandíbula. Radiograficamente todas as lesões se apresentavam como imagens uniloculares e a maioria (5 casos) se mostravam como imagem mista. O tamanho médio do tumor foi de 3,1 cm e 3 casos causavam deslocamento dos dentes envolvidos. Microscopicamente, todos os casos apresentavam várias áreas mineralizadas semelhantes a osso, imersas em um tecido conjuntivo celularizado. Dos 8 casos, 5 foram submetidos a excisão cirúrgica da lesão e 1 paciente recusou tratamento. Nos outros 2 casos, essa informação não estava disponível. Conclui-se que o FOs ocorrem mais comumente na mandíbula de pacientes do gênero feminino durante a quarta década de vida e se apresentam frequentemente como uma imagem radiográfica mista. Diagnósticos diferenciais coerentes são importantes para guiar a conduta clínica mais adequada. A correlação entre as características clínicas, imaginológicas e histopatológicas é a chave para estabelecer o diagnóstico correto.

Radioprotective Effect of Sodium Selenite on Developing Teeth

Radioprotective agents like selenium are used to reduce the damage caused by radiation in healthy tissues. The aim of this study was to evaluate the effect of sodium selenite on the development of the molars of offspring of rats irradiated during odontogenesis. Twenty pregnant rats were randomly divided into 4 groups: control, irradiated, selenium and selenium/irradiated. The selenium and selenium/irradiated groups received 0.3 mg/kg of sodium selenite at 18 days of pregnancy. The rats of the irradiated and selenium/irradiated groups received a single dose of 4 Gy of X rays on the abdominal region at the 19th day of pregnancy. The offspring was sacrificed at 3 and 4 days after birth for evaluation of the birefringence of the enamel organic matrix, and at 30 days for evaluation of the intercuspal dimensions of the molars. The selenium/irradiated group was similar to the irradiated group with respect to the thickness and irregularity of the enamel organic matrix region in the evaluated birefringence, as the intercuspal dimensions of the molars. In conclusion, sodium selenite had no radioprotective action on the development of the molars of offspring of rats irradiated during odontogenesis and had a toxic effect in the initial time.

Agentes radioprotetores, como o selênio, são utilizados para reduzir os danos causados pela radiação nos tecidos sadios. O objetivo nesse estudo foi avaliar o efeito do selenito de sódio no desenvolvimento de molares de filhotes de ratas irradiadas. Vinte ratas grávidas foram aleatoriamente divididas em 4 grupos: controle, irradiado, selênio e selênio/irradiado. Os animais dos grupos selênio e selênio/irradiado receberam 0.3 mg/kg de selenito de sódio aos 18 dias de gestação. Os animais dos grupos irradiado e selênio/irradiado receberam dose única de 4 Gy de radiação X na região abdominal aos 19 dias de gestação. Os filhotes foram sacrificados aos 3 e 4 dias após o nascimento para avaliação da birrefringência da matriz orgânica do esmalte, e aos 30 dias para avaliação das dimensões dos molares. Os resultados do grupo selênio/irradiado foram similares aos do irradiado, tanto em relação à espessura e irregularidade região da matriz orgânica do esmalte quanto às dimensões dos molares. Dessa forma, foi possível concluir que o selenito de sódio não exerceu ação radioprotetora no desenvolvimento de molares de filhotes de ratas irradiadas durante a odontogênese e apresentou efeito tóxico nos tempos iniciais.

Radioprotective Effect of Vitamin E in Parotid Glands: a Morphometric Analysis in Rats

The aim of this study was to evaluate the radioprotective effect of vitamin E on rat parotid glands by morphometric analysis. Sixty male rats were divided into 5 groups (n=6): control, in which animals received olive oil solution; olive oil/irradiated, in which animals received olive oil and were irradiated with a dose of 15 Gy of gamma radiation; irradiated, in which animals were irradiated with a dose of 15 Gy gamma radiation; vitamin E, which received α-tocopherol acetate solution; vitamin E/irradiated, which received α-tocopherol acetate solution before irradiation with a dose of 15 Gy gamma rays. Half of the animals were euthanized at 8 h, and the remaining at 30 days after irradiation. Both parotid glands were surgically removed and morphometric analysis of acinar cells was performed. Data were subjected to two-way ANOVA and Tukey's test (α=0.05). Morphometric analysis showed a significant reduction in the number of parotid acinar cells at 30 days in olive oil/irradiated and irradiated groups. In groups evaluated over time a significant reduction was shown at 30 days in olive oil/irradiated and irradiated groups, indicating that ionizing radiation caused tissue damage. The vitamin E/irradiated group presented more acinar cells than the irradiated group, but no statistically significant difference was observed (p>0.05). In conclusion, vitamin E seems to have failed as a radioprotective agent on acinar cells in rat parotid glands.

O objetivo neste estudo foi avaliar o efeito radioprotetor da vitamina E sobre glândulas parótidas de ratos por meio de análise morfométrica. Sessenta ratos machos foram divididos em cinco grupos: controle, no qual os animais receberam solução de óleo de oliva; óleo de oliva irradiado, em que os animais receberam óleo de oliva e foram irradiados com uma dose de 15 Gy de radiação gama; irradiado, em que os animais foram irradiados com uma dose de 15 Gy de radiação gama; vitamina E, no qual receberam solução de acetato α-tocoferol; vitamina E irradiado, os quais receberam solução de acetato de α-tocoferol antes da irradiação com uma dose de 15 Gy de radiação gama. Metade dos animais foi eutanasiada em 8 h, e o restante aos 30 dias após a irradiação. Ambas as glândulas parótidas foram removidas cirurgicamente e análise morfométrica das células acinares foi realizada. Os dados foram submetidos à Análise de Variância com 2 fatores e teste de Tukey (α=0,05). A análise morfométrica mostrou uma redução significativa no número de células acinares da glândula parótida aos 30 dias nos grupos óleo irradiado e irradiado. Nos grupos avaliados ao longo do tempo uma redução significativa foi mostrada aos 30 dias nos grupos óleo irradiado e irradiado, indicando que a radiação ionizante causou danos teciduais. O grupo vitamina E/irradiado apresentou mais células acinares que o grupo irradiado, mas diferença estatisticamente significante não foi observada. Em conclusão, a vitamina E parece ter fracassado como um agente radioprotetor nas células acinares das glândulas parótidas de ratos.

Ossifying fibroma of the jaws: a clinicopathological case series study.

The aim of this study was to assess the clinical, radiographic and microscopic features of a case series of ossifying fibroma (OF) of the jaws. For the study, all cases with OF diagnosis from the files of the Oral Pathology Laboratory, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil, were reviewed. Clinical data were obtained from the patient files and the radiographic features were evaluated in each case. All cases were reviewed microscopically to confirm the diagnosis. Eight cases were identified, 5 in females and 3 in males. The mean age of the patients was 33.7 years and most lesions (7 cases) occurred in the mandible. Radiographically, all lesions appeared as unilocular images and most of them (5 cases) were of mixed type. The mean size of the tumor was 3.1 cm and 3 cases caused displacement of the involved teeth. Microscopically, all cases showed several bone-like mineralized areas, immersed in the cellular connective tissue. From the 8 cases, 5 underwent surgical excision and 1 patient refused treatment. In the remaining 2 cases, this information was not available. In conclusion, OF occurs more commonly in women in the fourth decade of life, frequently as a mixed radiographic image in the mandible. Coherent differential diagnoses are important to guide the most adequate clinical approach. A correlation between clinical, imaginological and histopathological features is the key to establish the correct diagnosis.

Radioprotective effect of sodium selenite on bone repair in the tibia of ovariectomized rats.

This study evaluated protection by selenium (Se) in the bone repair process in ovariectomized rats after irradiation. For such purpose, 80 ovariectomized female Wistar rats were randomly divided into 4 experimental groups: ovariectomized (Ov), Ov/Se, Ov/irradiated (Irr) and Ov/ Se/Irr. A bone defect was created on the tibia of all animals 40 days after ovariectomy. Two days after surgery, only the Ov/Se and Ov/Se/Irr rats received 0.8 mg Se/kg. Three days after surgery, only the Ov/Irr and Ov/Se/Irr rats received 10 Gy of x-rays on the lower limb region. The animals were euthanized at 7, 14, 21 and 28 days after surgery to assess the repair process, which was evaluated by analysis of trabecular bone number (Masson Trichrome) and birefringence analysis (Picrosirius). It was possible to observe a delay in the bone repair process in the ovariectomized/irradiated group and similarity between the ovariectomized, Ov/Se and Ov/Se/Irr groups. In conclusion, sodium selenite exerted a radioprotective effect in the bone repair of tibia of ovariectomized rats without toxicity.

Radioprotective effect of sodium selenite on bone repair in the tibia of ovariectomized rats

This studyevaluated protection by selenium (Se) in the bone repair process in ovariectomized rats after irradiation. For such purpose, 80 ovariectomized female Wistar rats were randomly divided into 4 experimental groups: ovariectomized (Ov), Ov/Se, Ov/irradiated (Irr) and Ov/ Se/Irr. A bone defect was created on the tibia of all animals 40 days after ovariectomy. Two days after surgery, only the Ov/Se and Ov/Se/Irr rats received 0.8 mg Se/kg. Three days after surgery, only the Ov/Irr and Ov/Se/Irr rats received 10 Gy of x-rays on the lower limb region. The animals were euthanized at 7, 14, 21 and 28 days after surgery to assess the repair process, which was evaluated by analysis of trabecular bone number (Masson Trichrome) and birefringence analysis (Picrosirius). It was possible to observe a delay in the bone repair process in the ovariectomized/irradiated group and similarity between the ovariectomized, Ov/Se and Ov/Se/Irr groups. In conclusion, sodium selenite exerted a radioprotective effect in the bone repair of tibia of ovariectomized rats without toxicity.

Esse estudo avaliou a proteção do selênio no processo de reparação óssea em ratas ovariectomizadas após irradiação. Para isso, 80 ratas Wistar foram divididas aleatoriamente em 4 grupos experimentais: ovariectomizado, ovariectomizado/selênio, ovariectomizado/irradiado e ovariectomizado/selênio/irradiado. Foi realizado um defeito ósseo na tíbia de todos os animais 40 dias após ovariectomia. Dois dias após essa cirurgia, os animais dos grupos ovariectomizado/selênio e ovariectomizado/selênio/irradiado receberam 0,8 mg Se/kg. Três dias após a cirurgia, os animais dos grupos ovariectomizado/irradiado e ovariectomizado/selênio/irradiado receberam 10 Gy de radiação X na região de membros inferiores. Os animais foram sacrificados 7, 14, 21 e 28 dias após a cirurgia para avaliação do processo de reparo ósseo, que foi realizado pela análise do número de trabéculas ósseas (coloração Tricrômico de Masson) e pela análise de birrefringência (coloração de Picrosirius). Foi observado atraso no processo de reparo ósseo no grupo ovariectomizado/irradiado e semelhança entre os grupos ovariectomizado, ovariectomizado/selênio e ovariectomizado/selênio/irradiado. Foi possível concluir que o selenito de sódio exerceu efeito radioprotetor no processo de reparação de tíbias em ratas ovariectomizadas sem toxicidade.

Comparative evaluation among different materials to replace soft tissue in oral radiology studies

OBJECTIVE: The aim of this study was to establish which materials afford better simulation of soft tissues in Oral Radiology studies. MATERIAL AND METHODS: The sample was composed of four materials in eleven different thicknesses to simulate the soft tissues of the face. The mean values of the relative amounts of radiographic contrast of the materials were determined and compared to a gold standard value, which was obtained from 20 patients who were referred to have periapical radiographs taken of the left mandibular molars. Data were subjected to statistical analysis with Dunnett's test (p<0.05). RESULTS: The mean value of the relative amounts of contrast encountered in the patients was 0.47, with a range between 0.36 and 0.64 for all 44 material/thickness combinations. The majority of the tested materials showed values close to those of the patients' tissues, without statistically signifcant differences among them. The values of only three materials/thickness combinations differed statistically from those of the patients' tissues. CONCLUSIONS: Based on the results of the present study, it may be concluded that except for utility wax (4 mm and 8 mm) and water (4 mm), all materials tested at different thickness could be used as soft tissue substitute materials in Oral Radiology studies.