Avaliação de microdanos no osso: Uso de uma ferramenta complementar para visualização tridimensional

Objetivo: Demonstrar o uso da visualização tridimensional (3D) na avaliação dos microdanos no osso com imagens histológicas. Métodos: Foram utilizadas imagens histológicas obtidas de amostras de osso não desmineralizadas, incluídas em metilmetacrilato e coradas em Calceína e com Alaranjado de Xylenol. Imagens que continham microdanos (microtrincas, danos difusos e microfraturas), analisadas por microscopia de luz polarizada ou contraste de fase, foram processadas para criar uma imagem 3D. A imagem tridimensional foi gerada utilizando-se o plugin Interactive 3D Surface Plot para o software ImageJ. Resultados: A morfologia dos microdanos foi mais bem observada nas imagens 3D obtidas neste estudo, visualizada tanto em suas cores originais ou no esquema multicor (Spectrum LUT). O esquema multicor Spectrum LUT permitiu diferenciar melhor os microdanos em relação à profundidade, uma vez que a diferenciação por cores é baseada nas características da superfície analisada. Maiores valores de um ponto no eixo z é representando na imagem por cores mais quentes. Conclusões: O uso da visualização tridimensional de forma complementar à análise convencional dos microdanos aprimorou sobremaneira sua avaliação morfológica e permitiu avaliar estes microdanos em diferentes perspectivas manipulando a imagem em diferentes eixos e posições.Objectives: This technical report demonstrates the use of a 3D visualization tool to evaluate bone microdamage in histological sections. Methods: Histological sections obtained from non-demineralized bone fragments stained with Calcein and Xylenol Orange and embedded in methyl methacrylate were used. Sections containing microdamages (microcracks, diffuse damage and/or microfractures) were assessed to create a 3D image with the use of polarization and phase-contrast microscopies by light optical and confocal microscopes, respectively. The 3D images were created with the use of a plugin named “Interactive 3D Surface Plot” for ImageJ. Results: Microdamage morphology was better evaluated by means of the 3D image obtained, visualized in both plots of original colors and Spectrum LUT multicolor. The different colors in the Spectrum LUT highlighted the damage and improved visualization. Conclusions: The use of 3D visualization to supplement classic bone microdamage evaluation improves the assessment of damage morphology and enhances their analysis by changing the perspective in different views

Periodontal therapy for patients before and after radiotherapy : a review of the literature and topics of interest for clinicians

To review and discuss important topics regarding periodontal treatment pre- and post-radiotherapy for head and neck cancer in human patients; to discuss the references for adequate techniques, the appropriate moment for tooth extractions and periodontal management; and to discuss the prevention of osteoradionecrosis. Thirty-nine studies including original studies, randomized clinical trials (RCTs) and reviews were searched in online databases MEDLINE (PubMed) and the Cochrane library. No year of publication restriction was applied. Language was restricted to English, and the following Medical Subject Heading terms were used: radiotherapy, radiation therapy and periodontal treatment. Studies regarding periodontal treatment and tooth extraction that involved clinical management of irradiated patients were selected. The treatment of periodontal diseases before radiotherapy is mainly required to avoid future dental extraction and to reduce the development of osteoradionecrosis. Periodontal treatment in irradiated patients mostly includes scaling and root planing, extraction of condemned teeth and topical and systemic antimicrobial therapy. Tooth removal should be planned at least 14 days before the first day of radiation treatment. Particular care and mouthwashes should be taken during and after radiation. The management of irradiated patients represents a challenge for health professionals, including dentists. It is important to establish recommendations for clinicians concerning dental and periodontal management in irradiated patients before, during and after treatment

Effects of ionizing radiation on cortical bone microarchitecture: specific related alterations over time

Possui versão em CDFAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas GeraisTrabalho de Conclusão de Curso (Graduação)This study aimed to evaluate the cortical bone microarchitecture in rabbit tibias at intervals 7, 14 and 21 days after ionizing irradiation. Twelve adult male New Zealand rabbits were treated with a single radiation dose of 30Gy. The animals were randomly divided into 4 groups: Control (no radiation), Ir7, Ir14 and Ir21 days. Computadorized microtomography was used to analyze the microarchitecture of the cortical bone. The following parameters were used: cortical thickness (CtTh), bone volume (BV), total porosity (Ct.Po), intracortical porosity (CtPo (cl)), fractal dimension (FD) and degree of anisotropy (Ct.DA). One-way analysis of variance (ANOVA) was performed for all data followed by Tukey and Dunnet tests. The cortical thickness was different (p <0.01) between the control and irradiated groups, with thicker cortex to Ir 7 days. There was no difference between groups for total porosity, however, intracortical porosity revealed significance difference (p <0.001) between the irradiated groups and the control group, with a lower value for Ir7 days. The number of bone channels, fractal dimension and degree of anisotropy did not show significant difference between groups. The bone volume was lower in the Ir14 group in relation to control. In this way, the microarchitecture of the cortical bone can be affected by radiotherapy and the effects appear to be time-dependent. Cortical parameters found in the group Ir21 days were similar to the control group, suggesting that the cortical bone return to the regular conformation after 21 days

Zoledronic acid effects in the cortical bone channels network, lacunocanalicular system and biomechanical properties

O objetivo do presente trabalho foi avaliar a microarquitetura, caracterizando a rede de canais e o sistema lacunocanalicular, e também, as propriedades biomecânicas, do osso cortical de ratos Wistar tratados com Ácido Zoledrônico. Vinte e um ratos machos foram divididos da seguinte forma: 12 animais alocados no grupo de animais submetidos ao experimento no quarto mês de idade e 9 alocados no grupo de animais submetidos ao experimento no nono mês de idade. Dentro destes grupos, os mesmos foram divididos em grupos controle e teste, sendo que no grupo teste os animais receberam três doses, no esquema de 7,5 g/kg, semanalmente. Após o uso da medicação, três animais foram eutanasiados nos respectivos períodos, após a última dose: 14 dias, 42 dias e 75 dias. Todos os animais tiveram suas mandíbulas, tíbias e fêmures dissecados. As tíbias e mandíbulas foram descalcificadas e processadas para inclusão em parafina, enquanto que, os fêmures foram armazenados para os testes biomecânicos. Imagens histológicas digitalizadas, provenientes das mandíbulas e tíbias, foram analisadas utilizando o processo de segmentação interativa, acessando as características da microarquitetura da rede de canais. O processo de reconstrução tridimensional, para caracterização do sistema lacunocanalicular, foi realizado nos cortes seriados proveniente das tíbias. Os fêmures foram analisados com os ensaios de microdureza, compressão e flexão em três pontos. Os resultados revelaram que a microarquitetura da rede de canais não foi alterada nas mandíbulas, no entanto, nas tíbias, houve diferença significante apenas nos animais de 4 meses de idade, nos quesitos área dos canais (p 0.0031), desvio-padrão da área (p 0.0338), perímetro dos canais (p 0.0068), desvio padrão do perímetro (p 0.0297) e porcentagem de matriz (p 0.0235). Os testes biomecânicos revelaram resultados que indicavam uma melhora nas características analisadas, que foi correlacionada apenas com o aumento da idade e não com o uso do ácido zoledrônico. A visualização tridimensional possibilitou analisar a distribuição dos osteócitos e dos canais, caracterizando o sistema lacunocanalicular, e constatou-se que nos animais de 4 meses o uso da droga causou uma descontinuidade na estabilidade da distribuição dos osteócitos. Conclui-se que o ácido zoledrônico não interferiu na microarquitetura da rede de canais do osso cortical das mandíbulas, enquanto que nas tíbias, nos animais jovens, houve uma modificação na microarquitetura e no sistema lacunocanalicular, revelando uma topologia mais heterogênea quando comparadas ao grupo controle. As propriedades biomecânicas não sofreram alterações quanto ao uso da droga, sendo evidenciada melhora nos parâmetros analisados relacionada apenas ao aumento de idade nos animais.The aim of this study was to evaluate the microstructure, characterizing the bone channels network and the lacunocanalicular system, also, the biomechanical properties of the cortical bone of Wistar rats treated with Zoledronic Acid. Twenty-one male rats were separated as follows: 4-month-old (12 animals) and 9 month-old (9 animals). For each age they were divided in control and test group, and the test group received a 7.5 g/kg dose of the drug, once a week, for 3 weeks. In the 4 month-old test group they were euthanized at 14, 42 and 75 days after the drug injection and in the 9-month-old test group they were sacrificed at 14 and 75 days after medication. All animals had their mandible, tibia and femur dissected, and then, the mandible and tibia were decalcified and embedded in paraffin, and, the femur were stored for mechanical tests. Histological images were analyzed through developed algorithms using the SCILAB mathematical environment, getting percentage of bone matrix, ROI areas, ROI perimeters, their standard deviations and Lacunarity, as well, the images were accessed and processed to tridimensional visualization, to characterize the lacunocanalicular system. The femurs were analyzed by microhardness, three point bending and compression testing. The results revealed that the bone channels network in the mandible was not affected by the drug, whereas the tibia in the 4-month-old animals revealed a statistical difference between control and test groups, with the test group revealing more heterogeneity in the channels topography, as seen in results of bone matrix (p=0.0235), ROI area (p=0.0031), ROI area standard-deviation (p=0.0338), ROI perimeter (p=0.0068) and ROI perimeter standard-deviation (p=0.0297). The biomechanical tests showed an increased in strength, and that this event was age-related and not depending on the use of the drug. The tridimensional visualization allowed to analyze the osteocyte distribution in relation to the channels position, characterizing the lacunocanalicular system, and, it was found that the 4-month-old animals the drug caused a discontinuity in the stability of osteocyte distribution. In conclusion, the zoledronic acid not interfere in the bone channels network in the cortical bone of the mandible, however, in the tibia of the young animals, theres been an alteration in bone channels network and in the lacunocanalicular system, revealing more heterogeneity in the topography in these animals. The biomechanical properties were not altered after the use of the drugs, and the increased in strength being age-related

Efeitos da radioterapia na microestrutura do osso cortical : avaliação histológica em coelhos

Radiotherapy is a well established treatment resource for head and neck cancer, however, can directly affect the bone, which receive high doses of radiation during treatment. The bone tissue when irradiated shows important alterations in their morphology and constitution. The aim of this study was evaluate the effects of radiotherapy in cortical bone of tibia, with quantification of bone matrix and empty osteocytes lacunae, also, with analysis of bone microstructure. Fourteen female rabbits were used, divided into two equal groups: Control and Test. The test group received single dose of 15 Gy cobalt-60 radiation in tibia, bilaterally. After 75 days the animals were sacrificed and 1 cm segment of the tibia were removed, fixed in 10% formalin, decalcified in EDTA and processed for embedding in paraffin. The sections were stained with HE and histologic images were digitized. Images were analyzed through developed algorithms, using SCILAB mathematical environment. Using interactive segmentation was obtained the percentage of bone matrix, area and perimeter of the bone channels and lacunarity. For the percentage of osteocytes and empty lacunae, we used the method of elements counting. The results showed significant difference in percentage of bone by area (p = 0.0003) between the control (96.71%) and irradiated (94.25%) groups. Also, there was significant difference in area (p = 0.0173) and perimeter (p = 0.0437) of the channels and their respective standard deviations (area and perimeter p = 0.0072 p = 0.0039). The lacunarity also showed significant difference (p = 0.014) among the control (16.48) and irradiated (13.80) groups. There was no significant difference in percentage of empty osteocyte lacunae (p = 0.3177). According to results of this study, the radiotherapy causes reduction of bone matrix and modifies the architecture of bone channels network, making it more heterogeneous and less organized.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorMestre em OdontologiaA radioterapia representa um recurso bem estabelecido para o tratamento do câncer de cabeça e pescoço, no entanto, nessa região, afeta diretamente o osso, que é submetido a altas doses de radiação durante o tratamento. O tecido ósseo quando irradiado apresenta alterações importantes em sua morfologia e constituição. O objetivo deste trabalho foi avaliar os efeitos da radioterapia no tecido ósseo cortical de tíbia, quantificando matriz óssea e lacunas de osteócitos vazias, além de analisar a microestrutura da rede de canais ósseos. No estudo, foram utilizados 14 coelhos fêmeas, separados em dois grupos iguais: Controle e Teste. O grupo teste recebeu dose única de 15 Gy de radiação cobalto-60 na região da tíbia, bilateralmente. Após 75 dias, os animais foram sacrificados e segmentos de 1 cm da tíbia foram removidos, fixados em formol 10%, desmineralizados em EDTA e processados para inclusão em parafina. Os cortes foram corados em HE e as imagens histológicas foram digitalizadas. As imagens foram analisadas por algoritmos desenvolvidos em ambiente de programação SCILAB. Utilizando o método de segmentação interativa obteve-se a porcentagem de matriz óssea, área e perímetro dos canais ósseos e lacunaridade. Para obtenção da porcentagem de osteócitos e lacunas vazias utilizou-se o método de contagem de elementos. Os resultados mostraram diferença estatística significante na porcentagem de matriz óssea (p=0.0003) entre o grupo não irradiado (96.71%) e irradiado (94.25%). Também, houve diferença significante nas médias da área (p=0.0173) e perímetro (p=0.0437) dos canais, e seus respectivos desviospadrão (Área p=0.0072 e Perímetro p=0.0039). A lacunaridade também apresentou diferença significante (p=0.014), entre os grupos não irradiado (16.48) e irradiado (13.80). Não houve diferença estatística significante na porcentagem de lacunas vazias (p=0.3177). De acordo com os resultados pode-se concluir que a radioterapia provoca redução da matriz óssea e altera a arquitetura da rede de canais ósseos, tornando-a mais heterogênea e menos organizada

Sialolitíase ductal da glândula submandibular contendo cálculos gigantes: relato de dois casos

Introduction: The presence of calculi in Salivary Glands is considered a quite common phenomenon, however, some of these sialoliths could reach bigger sizes, and then be considered as giant calculus. Objective: The aim of the study was to report two cases of giant calculi in the submandibular salivary gland, also, to improve their analysis by means of their surface area measurement. Case Report: Two adult patients were diagnosed with signs and symptoms suggestive of sialolithiasis. Imaging exams were conducted, with the final diagnosis of Salivary Gland Calculi. Both calculi were surgically removed, under local anesthesia at the dentist’s office. The giant calculi were photographed, measured, and classified as giant calculi because both showed more than 15 mm in the highest axis, also, by heaving a significant surface area. Both cases resolved after surgery, with no history of recurrence. Conclusion: Giant sialoliths are uncommon. It is necessary to discuss this phenomenon aiming for a consensus among the scientific community regarding the classification of the salivary gland calculi. The two cases reported in this article exemplify the complimentary use of the calculation of the calculi surface area on clinical images, which should be considered as an adjuvant maneuver in the classification of salivary sialoliths.Introdução: A presença de cálculos relacionados às glândulas salivares maiores é relativamente comum, no entanto, alguns destes sialólitos podem aumentar consideravelmente de tamanho e serem categorizados como cálculos gigantes. Objetivo: O objetivo deste estudo é relatar dois casos clínicos de sialólitos gigantes em glândula submandibular e complementar a análise por meio da mensuração de área destes cálculos. Relato de Caso: Dois pacientes adultos apresentaram sinais e sintomas sugestivos de sialolitíase. Foram realizados exames de imagem complementares que permitiram delinear o diagnóstico clínico. Foram realizadas abordagens cirúrgicas para tratamento dos sialólitos gigantes, sob anestesia local e em ambiente ambulatorial. Os cálculos foram fotografados, medidos e classificados como gigantes por terem a maior medida de extensão que 15 mm, e por terem uma área total expressiva. Os dois casos tiveram resolução satisfatória, sem história de recidiva. Conclusão: Os sialólitos gigantes são achados incomuns. Faz-se necessário um consenso na comunidade científica quanto a classificação dos cálculos salivares quanto ao seu tamanho para fins de categorização. Os dois casos aqui relatados exemplificam bem o uso do cálculo da área total de superfície dos sialólitos como manobra complementar na classificação de cálculos gigantes

Tissue and serum sclerostin in bone-related lesions: a scoping review

Bone remodeling is extremely necessary for the renewal and maintenance of a healthy skeleton and consists of a process of bone resorption and formation, carried out, respectively, by osteoclasts and osteoblasts. In the coordination of bone remodeling are the osteocytes, and, therefore, the focus on markers related to the regulation of osteocyte activities can be clinically useful as markers of diagnosis, prognosis or monitoring of bone diseases. Sclerostin has been explored as a new biomarker of bone remodeling produced by osteocytes. Understanding its expression and pathways will potentially help us predict risk groups for bone tumor and tumor-like lesions in early stages. Thus, the clinical utility of this marker as diagnostic, prognostic, or monitoring tools during treatment still needs to be studied. In view of this, a scoping review is necessary for this matter. Electronic search to identify potentially relevant articles will be conducted in the following databases: Cochrane Library, Embase, Latin American and Caribbean Health Sciences (LILACS), MEDLINE PubMed, Scopus, and Web of Science. A search in grey literature will be conducted through Google Scholar and ProQuest thesis and dissertations databases. Additionally, the reference lists of included studies will be checked to identify potentially relevant articles. Experts in the area will be contacted to retrieve ongoing or not published studies. No time or language restriction will be applied to the search

Detection of single and mixed colonization of Candida species in patients with denture stomatitis

Aim: To evaluate the profile of the colonization by Candida spp. using presumptive identification to classify the patients with denture stomatitis as having single or mixed colonization, correlating with oral and systemic status. Methods: The CHROMagar Candida™ Medium (CC) for yeast culture and exfoliative cytology was used to identify colonization by Candida spp. and distinguish the different species of the Candida genus from patients with denture stomatitis (DS) and denture wearers without DS (control group). In addition, colonization was correlated with specific habits, such as tobacco and alcohol use, as well as with the use of systemic drugs. Results: Direct swabbing of whole unstimulated saliva (WUS) and palatal mucosa revealed colonization in 97.3% of the patients with DS. In the control group, 55.0% patients presented colonization. The presumptive identification found C. albicans as the most prevalent between both groups, respectively in 89.4% of the DS group and 40.0% from the control group. Regarding the nonalbicans species in the DS group, the most frequent were C. krusei (31.5%), C. glabrata (21.0%) C. tropicalis (15.7%) and Candida spp (2.6%). Smokers presented 90% of mixed isolates, and no C.albicans single colonization in the DS group, with statistically significant difference between smokers and non-smokers (p=0.0051). In the control group, the non-albicans species were C.glabrata (23.0%) and C.tropicalis (23.0%). The results of cytology from the DS group showed positive results in 22.2% of the cases. Conclusions: The use of CC was effective as a complementary method for the diagnosis of colonization by Candida spp. and DS, with the additional advantage of enabling a rapid presumptive identification of the specie. Smoking seemed to play a role in the colonization of oral mucosa by mixed albicans and non-albicans species. Mixed colonization seems to be more prevalent between patients with DS

Detection of single and mixed colonization of Candida species in patients with denture stomatitis

evaluate the profile of the colonization by Candida spp. using presumptive identification to classify the patients with denture stomatitis as having single or mixed colonization, correlating with oral and systemic status. Methods: The CHROMagar Candida Medium (CC) for yeast culture and exfoliative cytology was used to identify colonization by Candida spp. and distinguish the different species of the Candida genus from patients with denture stomatitis (DS) and denture wearers without DS (control group). In addition, colonization was correlated with specific habits, such as tobacco and alcohol use, as well as with the use of systemic drugs. Results: Direct swabbing of whole unstimulated saliva (WUS) and palatal mucosa revealed colonization in 97.3% of the patients with DS. In the control group, 55.0% patients presented colonization. The presumptive identification found C. albicans as the most prevalent between both groups, respectively in 89.4% of the DS group and 40.0% from the control group. Regarding the nonalbicans species in the DS group, the most frequent were C. krusei (31.5%), C. glabrata (21.0%) C. tropicalis (15.7%) and Candida spp (2.6%). Smokers presented 90% of mixed isolates, and no C.albicans single colonization in the DS group, with statistically significant difference between smokers and non-smokers (p=0.0051). In the control group, the non-albicans species were C.glabrata (23.0%) and C.tropicalis (23.0%). The results of cytology from the DS group showed positive results in 22.2% of the cases. Conclusions: The use of CC was effective as a complementary method for the diagnosis of colonization by Candida spp. and DS, with the additional advantage of enabling a rapid presumptive identification of the specie. Smoking seemed to play a role in the colonization of oral mucosa by mixed albicans and non-albicans species. Mixed colonization seems to be more prevalent between patients with DS

Dimensão fractal e lacunaridade como parâmetros de avaliação da qualidade óssea na mandíbula de indivíduos saudáveis: análise por meio da tomografia computadorizada de feixe cônico

Introduction: Bone quality can be assessed trough a texture analysis in imaging exams by Fractal dimension (FD) and lacunarity (Lac) measurements. DF represents the complexity of a fractal and Lac means distribution and size of the empty spaces. Objective: To evaluate trabecular bone quality through FD, Lac, and bone volume in the posterior region of the mandible using cone-beam computed tomography (CBCT) in healthy individuals, also comparing the results between males and females. Materials and Methods: 21 CBCT exams were used. The software ImageJ was used with ten sequential axial slices were selected for each patient, and the region of interest (ROI) was defined between the lower canine and first molar in both sides. The parameters were evaluated: a) Bone Volume (BV), Tissue Volume (TV) and BV/TV by binarization process; b) FD and Lac by the box-counting method in greyscale, without binarization. Results: When comparing the sides, BV and TV had a significant difference (p=0.02 e 0.01, respectively) with higher values on the right side. When comparing the sexes, there was no significant difference. The values for FD had an average of 0.87 for females and 0.86 for males. Lac values were 0.17 for females and 0.15 for males, in average. The age had negative significant correlation with bone volume. Conclusion: DF e Lac are viable parameters for analyse to trabecular bone quality in the mandible. Values were found lower than 1 for FD and lower than 0.17 for Lac in healthy individuals. FD and Lac had no difference between males and females. The trabecular bone in the posterior region of the mandible had higher values on the right side when compared to the left side, and there was no difference between sexes.Introdução: A qualidade óssea pode ser avaliada pela análise de textura nos exames de imagem, por meio da mensuração da dimensão fractal (DF) e lacunaridade (Lac). A DF está relacionada com a complexidade da organização estrutural óssea e a Lac representa a distribuição e o tamanho dos espaços vazios. Objetivo: Avaliar a qualidade óssea trabecular em região posterior da mandíbula por meio da DF e Lac e analisar o volume ósseo no exame de tomografia computadorizada de feixe cônico (TCFC), em indivíduos saudáveis, e, ainda, comparando homens e mulheres. Material e Métodos: 21 exames de TCFC foram utilizados. Utilizou-se o software ImageJ com dez cortes axiais sequenciais de cada paciente, delimitando a região de interesse (ROI) entre canino e primeiro molar inferiores, de ambos os lados. Foram avaliados os parâmetros: a) Bone Volume (BV), Tissue Volume (TV) e BV/TV, pelo processo de binarização; b) DF e Lac pelo método de Box-couting, em escala de cinza, sem binarização. Resultados: Na comparação entre os lados, BV e TV apresentaram diferença significativa (p=0,02 e 0,01, respectivamente), com maiores valores para o lado direito. Na comparação entre os sexos não houve diferença significativa. Os valores de DF apresentaram média de 0,87 para mulheres e 0,86 para homens. Valores de Lac foram em média 0,17 para mulheres e 0,15 para homens. A idade apresentou correlação negativa significativa com o volume ósseo. Conclusão: DF e Lac são parâmetros viáveis para serem analisados quando se trata de acessar a qualidade óssea trabecular em mandíbula. Foram encontrados valores menores que 1 para DF, e abaixo de 0,17 para Lac, em indivíduos saudáveis. Tanto DF quanto Lac não mostraram diferenças entre homens e mulheres. O osso trabecular na região posterior da mandíbula apresentou maior volume no lado direito em comparação ao esquerdo, e não houve diferença entre os sexos