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INTRODUCTION: Medication-associated osteonecrosis of the jaws (MRONJ) is characterized by the presence of exposed bone or an intraoral or extraoral fistula in the maxillofacial region in patients with a history of treatment with anti-resorptive and anti-angiogenic drugs, such as monoclonal antibodies, and without a history of radiotherapy or metastatic diseases in the area. OBJECTIVE: The aim of this study is to report a case of a pathological mandibular fracture in an area of MRONJ in a patient diagnosed with Crohn's disease treated with infliximab. CASE REPORT: A 53-year-old male patient, an active smoker for 35 years, diagnosed with Crohn's disease, undergoing intravenous administration of infliximab 300 mg for 1 year and 3 months, with no previous history of anti-angiogenic or anti-resorptive medication, presenting with an extraoral fistula in the submandibular region for 4 months, with painful symptoms, diagnosed as MRONJ. He was initially treated conservatively, using antimicrobial photodynamic therapy (aPDT), antibiotic therapy, and the PENTO protocol. However, the patient evolved with a pathological fracture in the mandibular parasymphysis, requiring surgical reconstruction. FINAL CONSIDERATIONS: Pathological fracture of the mandible is a complication of MRONJ that compromises the patient's quality of life. The management of patients with MRONJ is complex and challenging.

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OBJECTIVE: Assess the impact of photobiomodulation therapy (PBMT) on xerostomia, salivary flow rate (SFR) and composition in patients undergoing radiotherapy (RT) for head and neck cancer (HNC). STUDY DESIGN: Thirty patients undergoing RT (65 Gy) for HNC were enrolled. Saliva and xerostomia evaluations collected pre- and post-PBMT-RT. PBMT involved irradiation of extra and intraoral points, 15-20 sessions, 2-3 times/week. SFR, trace elements, total protein, alkaline phosphatase, xerostomia, and pH were analyzed. RESULTS: The average age was 60.7 years. After treatment, there was not a significant reduction in SFR and there was no difference on xerostomia. Significant reductions in Al, Cd, Fe, Ni, P, and Sb concentrations were observed, along with a significant increase in Mg concentration. Sample data were organized into 3 groups based on a self-organizing map. Low concentrations of Al, As, Co, Cr, Cu, Fe, Mn, Mo, S, Sr, and Zn were the primary discriminatory factors for group A, while group B consisted of post-PBMT-RT samples with high concentrations of Ca, K, Mg, Na, and S. CONCLUSIONS: PBMT prevented a significant reduction in SFR and xerostomia induced by radiation therapy. These findings suggest that PBMT prevents salivary gland damage minimizing the decline in salivary flow.

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MYH9 disease is a rare genetic disorder in which there is a mutation in the gene for the non-muscle myosin heavy chain IIA. It initially causes macrothrombocytopenia followed by other clinical manifestations. When the patient reaches adulthood, he can develop chronic kidney failure. Thus, the risk of suffering a hemorrhage, difficulty in repairing and, infections increases in individuals with this disease. In addition, the use of drugs in these patients should be carefully evaluated. An adult patient sought dental care with a complaint associated with a tooth with advanced dental caries. He had severe thrombocytopenia (7000 platelets/mm3 ), hearing loss, and chronic kidney failure. The diagnosis of MYH9 disease was confirmed through genotyping. After clinical examination, extraction was planned. Local and systemic procedures were used to prevent hemorrhage, especially postoperatively. Although the patient had an infection at the surgical wound site and no episode of postoperative bleeding, the repair process occurred normally. The purpose of this article is to report the surgical management of a patient with MYH9 disease.

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Parameter reproducibility in photobiomodulation therapy (PBMT) is still scarce in literature for the management of oral mucositis (OM). This study aimed to identify the most used PBMT dosimetry parameters (DP) and their efficacy in OM management after preconditioning for hematopoietic stem cell transplantation (HSCT). This research was conducted according to the PRISMA guidelines. The search for primary studies was in PubMed/MEDLINE, Web of Science, Embase, BVS, and Cochrane Library. Gray literature was verified on BDTD-Ibict and Open Gray. A total of 1044 studies were identified. Nine met the eligibility criteria for qualitative assessment and 7 for meta-analysis. The studies involved 396 patients submitted to preconditioning for HSCT, 211 with PBMT and 185 without PBMT in the OM management. The WHO scale was the most used to assess OM degree. The most used parameters were 660-nm wavelength, 40-mw power, 0.16-J energy, 1-W/cm2 power density, 4-J/cm2 energy density, and 0.04-cm2 spot size. The meta-analysis demonstrated that PBMT decreased the severity of OM, with a protection factor 20% higher than the control group (without PBMT), and when the parameters are similar to the DP mentioned, the protection factor increases to 94%. These most used DP with similarity seem to be a therapeutic strategy for the management of OM in this population.

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This study aimed to analyze Facebook's use as a pedagogical tool for teaching didactics for graduate students in Dentistry. Seventy-two adult students participated in this study. These students attended theoretical classes, developed practical activities by Facebook, and evaluated the course through a questionnaire. Tasks were analyzed concerning the following criteria: time torespond to assignments and whether they have been finished or not. Additionally, post type and students' reactions to posts were also evaluated. Forty-three (59.8%) students have considered Facebook as a good pedagogical resource. Only 5 (22%) students answered that they had some difficulty in responding to the assignments of the course through Facebook. Most students completed their tasks through Facebook. However, in general, most students only fulfilled the assignments close to the deadline. The main reactions of the students were likes and comments. Despite its limitations, Facebook seems to be a great pedagogical resource to be inserted in post-graduate education. In addition, the students still show little participation even being in the virtual environment of Facebook (AU).

O objetivo deste estudo foi analisar a utilização do Facebook como ferramenta pedagógica para o ensino de didática para alunos de graduação em Odontologia. Setenta e dois alunos adultos participaram da pesquisa. Esses alunos participaram de aulas teóricas, desenvolveram atividades práticas no Facebook e avaliaram o curso por meio de um questionário. As tarefas foram analisadas em relação aos seguintes critérios: tempo para responder às atividades e se elas foram realizadas de forma completa ou incompleta. Além disso, os tipos de postagens e as reações dos alunos às postagens também foram avaliados. Quarenta e três (59,8%) alunos consideraram o Facebook um bom recurso pedagógico. Apenas 5 (22%) alunos responderam que tiveram alguma dificuldade em responder às atividades do curso pelo Facebook. A maioria dos alunos concluiu suas tarefas por meio do Facebook. No entanto, em geral, a maioria dos alunos só cumpriu astarefas perto do prazo. As principais reações dos alunos foram curtidas e comentários. Apesar de suas limitações, o Facebook parece ser um grande recurso pedagógico a ser inserido na pós-graduação. Além disso, os alunos ainda se mostram pouco participativos mesmo estando no ambiente virtual do Facebook (AU).

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Epilepsy is defined as a group of symptoms resulting from several neuronal complications ranging from changes in consciousness and motor activity to sensory phenomena and aberrant behaviors. This health problem has been associated with cases of stigma that can seriously affect the patient's quality of life. This study's main objectivewas to investigate the knowledge and attitudes regarding the treatmentof patients diagnosed with epilepsy by undergraduate dentistry students. The methodology was based on applyinga structured questionnaire with 17 close-endedquestions that evaluated information such as sociodemographic data, knowledge about epilepsy and social tolerance. The sample consisted of 397 students enrolled in the Dentistry course atFederal University of Paranáand divided into: group 1, students attending the 1st to the 7th semester of the course,and group 2, students in the last semester of the course. Group 1 students had more opportunities to care for patients with epilepsy than group 2. Most students expressed positive attitudes towardliving with people suffering from epilepsy and considered that they could not exercise certain professional activities. The question with the least number of correct answers dealt with the treatment of patients with the disease. Students' knowledge of epilepsy was low. However, the level of positive attitudes towardliving with this type of patient was considered high (AU).

A epilepsia é definida como um complexo de sintomas resultantes de diversas complicações neuronais que variam de alterações da consciência e da atividade motora até fenômenos sensoriais e comportamentos aberrantes. Esse problema de saúde tem sido associado a casos de estigma que podem repercutir seriamente na qualidade de vida do paciente. Este estudo teve por objetivo principal investigar o conhecimento e as atitudes em relação ao manejo de pacientes com diagnóstico de epilepsia dos estudantes de graduação do curso de Odontologia. A metodologia foi baseada na aplicação de um questionário estruturado com 17 perguntas fechadas que avaliaram informações como dados sociodemográficos, conhecimento sobre epilepsia e tolerância social. A amostra foi composta por 397 estudantes matriculados no curso de Odontologia da Universidade Federal do Paraná e dividida em: grupo 1, alunos cursando do 1º até o 7º semestre do curso e grupo 2, alunos do último semestre do curso. Os estudantes dogrupo 1 tiveram mais oportunidades para atender pacientes com epilepsia do que os do grupo 2. A maioria dos estudantes manifestou atitudes positivas em relação ao convívio com pessoas que sofrem de epilepsia e considerou que elas não poderiam exercer determinadas atividades profissionais. A questão com menor número de acertos tratava do tratamento de pacientes com a doença. O conhecimento dos estudantes em relação à epilepsia foi baixo. Porém, o nível de atitudes positivas em relação ao convívio com esse tipo de paciente foi considerado alto (AU).

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BACKGROUND: Viral reactivation in patients undergoing immunosuppressive therapy after hematopoietic stem cell transplantation (HSCT) is a serious complication associated with significant morbidity and mortality. Infections caused by human herpes viruses such as herpes simplex virus (HSV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) can result in oral lesions. CASE PRESENTATION: A 40-year-old male patient who had undergone HSCT presented with ulcerated lesions in different areas of the mouth, for 7 months. The lesions had evolved to painful exophytic nodules with an erythematous, ulcerated surface. They were present on the tongue margins and soft and hard palate. Histological, immunohistochemical (IHC), and polymerase chain reaction analyses were performed, and the results were compatible with HSV-1 and -2 and CMV infections. Treatment comprised five sessions of antimicrobial photodynamic therapy (aPDT) and oral valganciclovir. Thirty days after combined antiviral therapy and aPDT, the lesions were completely resolved. Patient was followed up for 12 months without recurrence. CONCLUSION: Diagnosis and treatment of atypical oral infections in immunosuppressed patients is challenging. Assessment of both clinical and laboratory findings is mandatory for a conclusive diagnosis. The use of local antimicrobial and systemic therapies contributes to positive clinical response in such cases.

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The limited options for bone repair have led to an extensive research of the field and the development of alloplastic and xenogeneic grafts. The purpose of this study was to evaluate bone repair with two bone substitutes: deproteinized bovine bone (DBB) and biphasic calcium phosphate ceramic (BCP) in critical-size defect. A total of 8-mm defects were made in the parietal bones of rabbits (n=12). The animals were divided into three experimental groups: sham (defect filled with a blood clot), DBB (defect filled with DBB), and BCP (defect filled with BCP). After the experimental periods of 15 and 45 days, the animals were euthanized and submitted to histomorphometric analysis. The total defect area, mineralized tissue area, biomaterial area, and soft tissue area were evaluated. A greater amount of immature bone tissue and biomaterial particles were observed in the BCP group compared to DBB and sham at 45 days (p<0.05). There was no difference in the qualitative pattern of bone deposition between DBB and BCP. However, the sham group did not show osteoid islands along with the defect, presenting a greater amount of collagen fibers as well in relation to the DBB and BCP groups. There was a greater number of inflammatory cells in the DBB at 45 days compared to BCP and sham groups. In conclusion, BCP and DBB are options for optimizing the use of bone grafts for maxillofacial rehabilitation. Bone defects treated with BCP showed greater deposition of bone tissue at 45 days.

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BACKGROUND: Schizophrenia (SCZ) presents complex challenges related to diagnosis and clinical monitoring. The study of conditions associated with SCZ can be facilitated by using potential markers and patterns that provide information to support the diagnosis and oral health. METHODS: The salivary composition of patients diagnosed with SCZ (n = 50) was evaluated and compared to the control (n = 50). Saliva samples from male patients were collected and clinical parameters were evaluated. The concentration of total proteins and amylase were determined and salivary macro- and microelements were quantified by ICP OES and ICP-MS. Exploratory data analysis based on artificial intelligence tools was used in the investigation. RESULTS: There was a significant increase in the salivary concentrations of Al, Fe, Li, Mg, Na, and V, higher prevalence of caries (p < 0.001), periodontal disease (p < 0.001), and reduced salivary flow rate (p = 0.019) in SCZ patients. Also, samples were grouped into six clusters. As, Co, Cr, Cu, Mn, Mo, Ni, Se, and Sr were correlated with each other, while Fe, K, Li, Ti, and V showed the highest concentrations in the samples distributed in the clusters with the highest association between SZC patients and controls. CONCLUSIONS: The results obtained indicate changes in salivary flow, organic composition, and levels of macro- and microelements in SCZ patients. Salivary concentrations of Fe, Mg, and Na may be related to oral conditions, higher prevalence of caries, and periodontal disease. The exploratory analysis showed different patterns in the salivary composition of SCZ patients impacted by associations between oral health conditions and the use of medications. Future studies are encouraged to confirm the results investigated in this study.

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Abstract The limited options for bone repair have led to an extensive research of the field and the development of alloplastic and xenogeneic grafts. The purpose of this study was to evaluate bone repair with two bone substitutes: deproteinized bovine bone (DBB) and biphasic calcium phosphate ceramic (BCP) in critical-size defect. A total of 8-mm defects were made in the parietal bones of rabbits (n=12). The animals were divided into three experimental groups: sham (defect filled with a blood clot), DBB (defect filled with DBB), and BCP (defect filled with BCP). After the experimental periods of 15 and 45 days, the animals were euthanized and submitted to histomorphometric analysis. The total defect area, mineralized tissue area, biomaterial area, and soft tissue area were evaluated. A greater amount of immature bone tissue and biomaterial particles were observed in the BCP group compared to DBB and sham at 45 days (p<0.05). There was no difference in the qualitative pattern of bone deposition between DBB and BCP. However, the sham group did not show osteoid islands along with the defect, presenting a greater amount of collagen fibers as well in relation to the DBB and BCP groups. There was a greater number of inflammatory cells in the DBB at 45 days compared to BCP and sham groups. In conclusion, BCP and DBB are options for optimizing the use of bone grafts for maxillofacial rehabilitation. Bone defects treated with BCP showed greater deposition of bone tissue at 45 days.

Resumo As opções limitadas para reparo ósseo levaram ao desenvolvimento de abrangente pesquisa na área de enxertos aloplásticos e xenogênicos. O objetivo deste estudo foi avaliar o reparo ósseo com dois substitutos ósseos: osso bovino desproteinizado (DBB) e cerâmica fosfática de cálcio bifásica (BCP) em defeito de tamanho crítico. Material e métodos: defeitos críticos de 8 mm foram feitos nos ossos parietais de coelhos (n=12). Os animais foram divididos em três grupos experimentais: sham (defeito preenchido com coágulo sanguíneo), DBB (defeito preenchido com DBB) e BCP (defeito preenchido com BCP). Após os períodos experimentais de 15 e 45 dias, os animais foram sacrificados e submetidos à análise histomorfométrica. Foram avaliadas a área total de defeitos, área de tecidos mineralizados, área de biomateriais e área de tecidos moles. Resultados: maior quantidade de tecido ósseo imaturo e de partículas de biomaterial foram observados no grupo BCP em comparação aos grupos DBB e sham aos 45 dias (p<0,05). Não houve diferença no padrão qualitativo de deposição óssea entre DBB e BCP. Ainda, o grupo sham não apresentou ilhas osteóides ao longo do defeito, apresentando maior quantidade de fibras colágenas em relação aos grupos DBB e BCP. Houve maior quantidade de células inflamatórias no DBB aos 45 dias em comparação aos grupos BCP e sham. Conclusões: BCP e DBB são opções para otimizar o uso de enxertos ósseos na reabilitação de pacientes. Defeitos ósseos tratados com BCP mostraram maior deposição de tecido ósseo aos 45 dias.

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AIMS: The aim of this study was to compare individuals with and without schizophrenia through the characteristics of the palate, such as width, length, depth, palate shape, and upper dental arch shape. METHODS AND RESULTS: The sample was divided into one case group (n = 45) and two control groups (n = 90; 45 individuals each group). Groups were paired by variables: sex, age, and malocclusion type. All analyses were performed on upper dental arch plaster models. All individuals were male and the mean age was 28.56 (SD: 7.82) years. The frequency of the malocclusion type observed was 54.1% (Class I), 22.2% (Class II), and 23.7% (Class III). Statistically significant difference was observed between the case and control groups for the variables palate shape (P = .004) and upper dental arch shape (P = .003). The case group had a higher frequency of the deep or grooved palate shape (57.8%) and parabolic dental arch shape (48.9%). There was no statistically significant difference for the palate width, length, and depth (P > .05). CONCLUSIONS: There was an evidence that the deep or grooved palate shape and parabolic dental arch shape are morphological characteristics of the palate in men with schizophrenia.

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The aim of this study was to evaluate the effect of acute sepsis in the periodontal ligament, alveolar and furcation bone in absence of periodontitis induction through histological and immunohistochemical analyses. A septic rat model was established by cecal ligation and puncture (CLP). Twelve rats were randomly divided into CLP (n=6) and Sham (n=6) groups. The animals were euthanized at 24 h and hemimandibles were submitted to histomorfometric (bone matrix, collagenous fibers, fibroblasts, osteocytes, inflammatory cells, and blood vessels) and immunohistochemical (BMP-2/4, RANKL and osteocalcin) evaluation in alveolar bone, furcation bone and periodontal ligament. Our results demonstrated that histomorphometric parameters were similar in alveolar bone, furcation bone and periodontal ligament of Sham and CLP rats. Regarding to immunohistochemical analyses, the number of BMP-2/4 and RANKL immunolabeled cells was also similar in both groups. Furthermore, it was detected a reduction in the osteocalcin immunolabeled cells in periodontal ligaments of CLP compared to Sham rats (p=0.0014). In conclusion, the acute sepsis induction resulted in reduced number of osteocalcin labelled cells in periodontal ligament region. Moreover, no significant histological differences were observed in the periodontium of rats under acute sepsis. Considering the role of osteocalcin in bone remodeling, the study contributes to revealing the importance of careful periodontal evaluation in the presence of sepsis.

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Abstract The aim of this study was to evaluate the effect of acute sepsis in the periodontal ligament, alveolar and furcation bone in absence of periodontitis induction through histological and immunohistochemical analyses. A septic rat model was established by cecal ligation and puncture (CLP). Twelve rats were randomly divided into CLP (n=6) and Sham (n=6) groups. The animals were euthanized at 24 h and hemimandibles were submitted to histomorfometric (bone matrix, collagenous fibers, fibroblasts, osteocytes, inflammatory cells, and blood vessels) and immunohistochemical (BMP-2/4, RANKL and osteocalcin) evaluation in alveolar bone, furcation bone and periodontal ligament. Our results demonstrated that histomorphometric parameters were similar in alveolar bone, furcation bone and periodontal ligament of Sham and CLP rats. Regarding to immunohistochemical analyses, the number of BMP-2/4 and RANKL immunolabeled cells was also similar in both groups. Furthermore, it was detected a reduction in the osteocalcin immunolabeled cells in periodontal ligaments of CLP compared to Sham rats (p=0.0014). In conclusion, the acute sepsis induction resulted in reduced number of osteocalcin labelled cells in periodontal ligament region. Moreover, no significant histological differences were observed in the periodontium of rats under acute sepsis. Considering the role of osteocalcin in bone remodeling, the study contributes to revealing the importance of careful periodontal evaluation in the presence of sepsis.

Resumo O objetivo deste estudo foi avaliar o efeito da sepse aguda no ligamento periodontal, osso alveolar e osso da furca por meio de análise histológica e imunohistoquímica. O modelo de sepse em ratos foi estabelecido pelo procedimento de ligação e perfuração do ceco (CLP). Doze ratos foram divididos de forma randomizada em ratos sépticos (n=6) e controle - grupo Sham (n=6). Os animais foram eutanasiados após 24 horas e suas hemimandíbulas foram submetidas aos procedimentos histotécnicos para análise histomorfométricos (matriz óssea, fibras colágenas, fibroblastos, osteócitos, células inflamatórias e vasos sanguíneos) e imunohistoquímicos (BMP-2/4, RANKL e osteocalcina) no osso alveolar, osso de furca e ligamento periodontal. Nossos resultados demonstraram que os parâmetros histomorfométricos foram similares no osso alveolar, osso de furca e ligamento periodontal dos animais do grupo sepse e do grupo Sham. Em relação à análise por imunohistoquímica, o número de células imunomarcadas para BMP-2/4 e RANKL também foi similar em ambos os grupos. Entretanto, houve redução (p=0.0014) no número de células imunomarcadas para osteocalcina no ligamento periodontal de ratos sépticos em relação ao grupo Sham. Como conclusão, o estabelecimento de sepse aguda resultou em um número reduzido de células imunomarcadas para osteocalcina na região do ligamento periodontal (p=0,0014). Além disso, não foram observadas diferenças histológicas significativas no periodonto de ratos na presença de sepse aguda. Considerando o papel da osteocalcina na remodelação óssea, este estudo contribui para revelar a importância da avaliação periodontal cuidadosa na presença de sepse.

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Objective: To evaluate the effects of alendronate (AL), a bisphosphonate, on visual bone density by means of a radiographic analysis. Material and methods: Sixty-two Wistar rats were divided into four groups: Group AA (AL with autogenous graft); group AW (AL without autogenous graft) both receiving AL on alternate days for 4 weeks before surgery; control group CA (with autogenous graft); group CW (without autogenous graft) both receiving saline solution before surgery. Experimental periods of evaluation were 2 weeks and 4 weeks postsurgery. Conventional and digital radiographs were obtained, and a 5-point grading system (score) was used to assess visual radiographic bone density. Results: There were no statistical differences between CA and AA groups at 2 and 4 weeks. The AA group had a higher mean score of bone density than the CW and AW groups at 2 weeks (P < 0.05). The CA and AA groups had higher scores of bone density than the CW and AW groups at 4 weeks (P < 0.05). Conclusions: Treatment with AL did not affect radiographic bone density at 2 and 4 weeks after surgery. The presence of an autograft resulted in higher scores of bone density. (AU)

Objetivo: Avaliar os efeitos do alendronato (AL), um bisfosfonato, na densidade óssea através de uma análise radiográfica. Material e métodos: Sessenta e dois ratos Wistar foram divididos em quatro grupos: Grupo AA (AL com enxerto ósseo autógeno); grupo AW (AL sem enxerto ósseo autógeno); ambos receberam AL em dias alternados durante 4 semanas antes da cirurgia; grupo controle CA (com enxerto ósseo autógeno); grupo CW (sem enxerto ósseo autógeno) ambos receberam solução salina antes da cirurgia. Os tempos experimentais de avaliação foram 2 e 4 semanas após a cirurgia. Radiografias convencionais e digitais foram realizadas, e um sistema de escore de 5 pontos foi utilizado para avaliar a densidade óssea radiográfica visualmente. Resultados: Não houve diferença estatisticamente significativa entre os grupos CA e AA em 2 e 4 semanas. O grupo AA apresentou maior escore de densidade óssea do que os grupos CW e AW em 2 semanas (p < 0.05). Os grupos CA e AA apresentaram maior escore de densidade óssea do que os grupos AW e CW em 4 semanas (p < 0.05). Conclusões: O tratamento com AL não interferiu na densidade óssea radiográfica em 2 e 4 semanas após cirurgia. A presença do enxerto resultou em maior escore de densidade óssea. (AU)

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Aim: The aim of this study was to evaluate knowledge and attitudes regarding potentially malignant oral lesions and oral cancer among undergraduate dental students with or without training in the oral medicine. Methods: A cross-sectional study was undertaken to assess all undergraduate dental student (1st to 5th year) in two private universities in the state of Paraná, Brazil. A structured questionnaire about knowledge regarding potentially malignant oral lesions, continuing education, and different approaches to diagnosis was administered to dental students with or without training in the oral medicine discipline between May and July 2015. Descriptive statistics were obtained, and the data were analyzed using a chi-square test to compare knowledge in dental students. Results: A total of 662 undergraduate dental students were invited to participate, and the response rate was 97.6% (n = 646). Of the responders, 472 were female (73.1%), 168 were male (26.0%), and 6 did not declare what sex they were (0.9%). Undergraduate dental students who had previously studied oral medicine tended to report that they always perform complete intraoral examination (76.3%) and identified alcohol (87%) and tobacco consumption (97%) and sun exposure (80%) as major risk factors for developing oral cancer. While students who had not yet studied oral medicine poorly identified these factors. Students who had previously studied the discipline did not identify cheilitis actinica (26%) and erythroplakia (32%) as potentially malignant lesions. Only, 32.6% of dental students participate in continuing education during the past year. Conclusions: Dental students trained in the oral medicine discipline exhibited satisfactory knowledge necessary for the prevention and early identification of potentially malignant oral lesions and oral cancer. Continuing education during undergraduate and after academic training is very important

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PURPOSE: Low-level laser therapy (LLLT) can increase bone metabolism, cell proliferation, and maturation, and reduce inflammation, while platelet concentrate (PC) assists bone healing process by releasing proteins and growth factors. Here, we evaluated the efficacy of combined LLLT and PC therapy in the healing of critical-size bone defects. MATERIALS AND METHODS: Calvarial critical-size defects 5 mm in diameter were made in 48 Wistar rats. Bones were removed, milled, and used as autogenous bone grafts. Animals were randomized into four groups: LP (LLLT + PC), PC, L (LLLT), and C (control, autogenous graft only). Animals were sacrificed at day 30 and 60 post-surgery. Specimens were submitted to radiographic (digital and conventional), histological, histomorphometric, and immunohistochemical analyses. RESULTS: Digital radiography was shown to be a better image analysis method compared with conventional radiography. Histological analysis demonstrated a significant difference in bone formation between animals in group L (p = 0.049) at day 60 than in other groups. Higher rates of inflammatory infiltrates and fibrosis were observed in the LP and PC groups at days 30 and 60, whereas the groups not receiving PC showed a higher rate of bone maturity. The inflammatory processes were reduced in the animals in the L group, together with new bone formation and maturation. Groups L and C had higher scores of positive osteocalcin immunostaining in bone and extracellular matrix. CONCLUSIONS: LLLT reduces inflammation and contributes to increased bone formation. PC treatment was shown to maintain connective tissue and to induce fibrosis during bone repair. Combined LLLT and PC treatment did not improve bone repair.

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OBJECTIVES: The aim of this study was to verify the likely influence of presurgical administration of low doses of alendronate sodium in craniofacial bone repair and correlate the histological frame found on reparative tissue to the immunohistochemical presence of IGF1, IGF2, and osteopontin (OP). MATERIALS AND METHODS: In total, 120 rats were randomly allocated into four groups: group C (control), group OA (autogenous bone), group B (bisphosphonates), and group OA-B (autogenous bone + bisphosphonates). Groups B and OA-B received alendronate sodium (ALN) 0.01 mg/kg subcutaneously on alternate days for 4 weeks. Groups C and OA received saline solution. Critical 5-mm defects were created in rat calvaria, which were filled with blood clot in groups C and B and with autogenous bone in groups OA and OA-B. The animals were euthanized at 15 or 30 days postoperatively. Histological analysis and immunohistochemistry of IGF1, IGF2, and OP proteins was performed. Immunohistochemistry evaluated the expression in cells and extracellular matrix. RESULTS: Groups C and B revealed healing predominantly characterized by connective tissue. In groups OA and OA-B, healing of connective tissue and neoformation of compact bone was observed. Expression of IGF1 an OP was present in all specimens. IGF1 expression in cells was more pronounced in groups OA and OA-B 15 days postoperatively. The expression of IGF2 was only observed in groups OA and OA-B, with greater intensity in group OA-B 30 days postoperatively. OP expression was only observed in cells and not in the extracellular matrix and was more pronounced in group OA 15 days postoperatively. CONCLUSIONS: The application of systemic ALN at a dose of 0.01 mg/kg did not improve cranial bone matrix deposition. Nevertheless, the expression of IGF1 and OP and a slight marking of IGF2 were observed especially in groups OA and OA-B in the wound healing process. Future studies should assess higher doses of ALN to verify its influence on bone repair. CLINICAL RELEVANCE: The systemic use of ALN 0.01 mg/kg on alternate days 4 weeks prior to surgery did not interfere with bone repair.

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Abstract The aim of this study was to evaluate the stress and dislodgement resistance by finite element analysis of different types of fixation in mandibular orthognathic surgery. A 3D solid finite element model of a hemi-mandible was obtained. A bilateral sagittal split osteotomy was simulated and the distal segment was advanced 5 mm forward. After the adjustment and superimposing of segments, 9 different types of osteosynthesis with 2.0 miniplates and screws were simulated: A, one 4-hole conventional straight miniplate; B, one 4-hole locking straight miniplate; C, one 4-hole conventional miniplate and one bicortical screw; D, one 4-hole locking miniplate and 1 bicortical screws; E, one 6-hole conventional straight miniplate; F, one 6-hole locking miniplate; G, two 4-hole conventional straight miniplates; H, two 4-hole locking straight miniplates; and I, 3 bicortical screws in an inverted-L pattern. In each model, forces simulating the masticatory muscles were applied. The values of stress in the plates and screws were checked. The dislodgement resistance was checked at the proximal segment since the distal segment was stable because of the screen at the occlusal tooth. The regions with the lowest and highest displacement were measured. The offset between the osteotomized segments was verified by millimeter intervals. Inverted-L with bicortical screws was the model that had the lowest dislodgment and the model with the lowest tension was the one with two conventional plates. The results suggest that the tension was better distributed in the locking miniplates, but the locking screws presented higher concentration of tension.

Resumo O objetivo deste estudo foi verificar o estresse e a resistência ao deslocamento, pela análise de elementos finitos, de diferentes tipos de fixação em cirurgia ortognática mandibular. Um modelo 3D de elementos finitos sólidos de uma hemi-mandíbula foi obtido. Uma osteotomia sagital bilateral foi simulada e o segmento distal foi avançado 5 mm. Após o ajuste e sobreposição dos segmentos, foram simulados 9 diferentes tipos de osteossíntese com miniplacas e parafusos 2.0: A, uma miniplaca reta convencional de 4 furos; B, uma miniplaca reta lock de 4 furos; C, uma miniplaca convencional de 4 furos e um parafuso bicortical; D, uma placa lock de 4 furos e 1 parafuso bicortical; E, uma miniplaca reta convencional de 6 furos; F, uma miniplaca lock de 6 furos; G, duas miniplacas retas convencionais de 4 furos; H, duas miniplacas lock de 4 furos; e I, três parafusos bicorticais em um padrão L invertido. Em cada modelo foram aplicadas forças simulando os músculos mastigatórios. Foram verificados os valores da tensão nas placas e parafusos. A resistência ao deslocamento foi verificada no segmento proximal, uma vez que o segmento distal era estável. Foi medida a região com o maior deslocamento inferior e superior. O deslocamento entre os segmentos osteotomizados foi verificado por intervalos milimétricos. Parafusos bicorticais em L invertido foram o modelo que teve o menor descolamento inferior, e o modelo com a tensão mais baixa foi o de duas placas convencionais. Os resultados sugerem que a tensão foi melhor distribuída nas miniplacas do tipo lock, mas os parafusos de fixação apresentaram maior concentração de tensão.

Assuntos

RESUMO

The aim of this study was to evaluate the stress and dislodgement resistance by finite element analysis of different types of fixation in mandibular orthognathic surgery. A 3D solid finite element model of a hemi-mandible was obtained. A bilateral sagittal split osteotomy was simulated and the distal segment was advanced 5 mm forward. After the adjustment and superimposing of segments, 9 different types of osteosynthesis with 2.0 miniplates and screws were simulated: A, one 4-hole conventional straight miniplate; B, one 4-hole locking straight miniplate; C, one 4-hole conventional miniplate and one bicortical screw; D, one 4-hole locking miniplate and 1 bicortical screws; E, one 6-hole conventional straight miniplate; F, one 6-hole locking miniplate; G, two 4-hole conventional straight miniplates; H, two 4-hole locking straight miniplates; and I, 3 bicortical screws in an inverted-L pattern. In each model, forces simulating the masticatory muscles were applied. The values of stress in the plates and screws were checked. The dislodgement resistance was checked at the proximal segment since the distal segment was stable because of the screen at the occlusal tooth. The regions with the lowest and highest displacement were measured. The offset between the osteotomized segments was verified by millimeter intervals. Inverted-L with bicortical screws was the model that had the lowest dislodgment and the model with the lowest tension was the one with two conventional plates. The results suggest that the tension was better distributed in the locking miniplates, but the locking screws presented higher concentration of tension.

Assuntos