Optimizing cone-beam computed tomography exposure for an effective radiation dose and image quality balance.

Purpose: The aim of this study was to evaluate the influence of different cone-beam computed tomography (CBCT) acquisition protocols on reducing the effective radiation dose while maintaining image quality. Materials and Methods: The effective dose emitted by a CBCT device was calculated using thermoluminescent dosimeters placed in a Rando Alderson phantom. Image quality was assessed by 3 experienced evaluators. The relationship between image quality and confidence was evaluated using the Fisher exact test, and the agreement among raters was assessed using the kappa test. Multiple linear regression analysis was performed to investigate whether the technical parameters could predict the effective dose. P-values<0.05 were considered to indicate statistical significance. Results: The optimized protocol (3 mA, 99 kVp, and 450 projection images) demonstrated good image quality and a lower effective dose for radiation-sensitive organs. Image quality and confidence had consistent values for all structures (P<0.05). Multiple linear regression analysis resulted in a statistically significant model. The milliamperage (b=0.504; t=3.406; P=0.027), kilovoltage peak (b=0.589; t=3.979; P=0.016) and number of projection images (b=0.557; t=3.762; P=0.020) were predictors of the effective dose. Conclusion: Optimized CBCT acquisition protocols can significantly reduce the effective radiation dose while maintaining acceptable image quality by adjusting the milliamperage and projection images.

Diagnostic capability of artificial intelligence tools for detecting and classifying odontogenic cysts and tumors: a systematic review and meta-analysis.

OBJECTIVE: To evaluate the diagnostic capability of artificial intelligence (AI) for detecting and classifying odontogenic cysts and tumors, with special emphasis on odontogenic keratocyst (OKC) and ameloblastoma. STUDY DESIGN: Nine electronic databases and the gray literature were examined. Human-based studies using AI algorithms to detect or classify odontogenic cysts and tumors by using panoramic radiographs or CBCT were included. Diagnostic tests were evaluated, and a meta-analysis was performed for classifying OKCs and ameloblastomas. Heterogeneity, risk of bias, and certainty of evidence were evaluated. RESULTS: Twelve studies concluded that AI is a promising tool for the detection and/or classification of lesions, producing high diagnostic test values. Three articles assessed the sensitivity of convolutional neural networks in classifying similar lesions using panoramic radiographs, specifically OKC and ameloblastoma. The accuracy was 0.893 (95% CI 0.832-0.954). AI applied to cone beam computed tomography produced superior accuracy based on only 4 studies. The results revealed heterogeneity in the models used, variations in imaging examinations, and discrepancies in the presentation of metrics. CONCLUSION: AI tools exhibited a relatively high level of accuracy in detecting and classifying OKC and ameloblastoma. Panoramic radiography appears to be an accurate method for AI-based classification of these lesions, albeit with a low level of certainty. The accuracy of CBCT model data appears to be high and promising, although with limited available data.

Traumatic Ulcerative Granuloma with Stromal Eosinophilia on the Tongue.

BACKGROUND: Traumatic Ulcerative Granuloma with Stromal Eosinophilia, commonly known as Eosinophilic Ulcer, is a reactive solitary and self-limiting benign lesion. It manifests as a punched-out ulcer with a distinct surrounding indurated border, often raising concerns about malignancy. METHODS: A 44-year-old male presented with a painless, indurated tongue ulcer evolving over three months. Despite being asymptomatic, the patient underwent an incisional biopsy due to suspicions of oral squamous cell carcinoma. RESULTS: Histological analysis revealed a disrupted epithelial lining, dense necrotic connective tissue, and a fibrino-purulent pseudomembrane. Proximal to the ulcer, a collar-like projection of reactive epithelial tissue hyperplasia was noted, accompanied by mononuclear cells and a predominantly histiocytic infiltrate in the submucosal layer surrounding skeletal muscle fibers. The final diagnosis was Traumatic Ulcerative Granuloma with Stromal Eosinophilia. Remarkably, the lesion spontaneously healed within 2 weeks post-biopsy, with no recurrence over 6 months. CONCLUSION: This case emphasizes considering this benign condition in the differential diagnosis of oral ulcers, highlighting the importance of accurate histopathological evaluation to rule out cancer.

Prevalence of oral manifestations of leprosy: a systematic review and meta-analysis.

OBJECTIVE: To evaluate the prevalence of oral manifestations of leprosy. STUDY DESIGN: This systematic review with meta-analysis was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and included cross-sectional studies by 2 independent reviewers in 2 phases, who reported bacilloscopic-confirmed oral manifestations of leprosy. Studies were selected based on predetermined eligibility criteria. Searches in 6 main databases were performed, such as PubMed/MEDLINE, Embase, Scopus, Web of Science, LILACS/BVS, and LIVIVO, in addition to the gray literature. The risk of bias was assessed using the JBI Checklist for Analytical Cross-Sectional Studies, and the quantitative synthesis of the data was performed using the Jamovi 2.3 application. RESULTS: Ten studies were included, and the meta-analysis was performed with 917 patients with different types of leprosy. The overall prevalence of oral alterations was 6.0% (95% IC, 0.02-0.11; I2 = 97.01%; Q = 75.56), with plaques (27.2%), infiltrations (18.1%), and macules (15.1%) being the most prevalent fundamental lesions, especially in multibacillary patients. CONCLUSIONS: Even though there is no oral pathognomonic lesion of leprosy, this infectious disease can manifest in oral tissues in different ways, depending mainly on the leprosy type and stage of treatment.

Risk of oral cancer in patients with graft-vs-host disease: A systematic review and meta-analysis.

OBJECTIVE: This systematic review was undertaken to determine the risk of oral cancer in patients with chronic graft-vs-host disease (cGvHD). STUDY DESIGN: The search was conducted in 6 electronic databases (PubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, and LIVIVO) and gray literature (Google Scholar, Open Gray, and ProQuest) for studies published up to November 2021. RESULTS: Of the 13 cohorts included in qualitative synthesis, 9 were eligible for the quantitative analysis. The meta-analysis showed that the presence of cGvHD increased the risk of developing oral cancer (risk ratio [RR] = 2.78; 95% CI, 1.27-6.08; I2 = 46%; P = .01). A subgroup meta-analysis revealed a higher risk of oral cancer in Asian samples exposed to cGvHD (RR = 2.50; 95% CI, 1.54-4.04; I2 = 0%; P = .0002), which was not seen in the pooled analysis of European samples (P = .24). The overall methodological quality of most studies included was "good." The cumulative evidence (Grading of Recommendations Assessment, Development and Evaluation) was considered moderate and of very low confidence for Asian and European studies, respectively. CONCLUSIONS: Patients with cGvHD resulting from allogenic hematopoietic stem cell transplantation run an increased risk of developing oral cancer. Hence, it is recommended that patients with cGvHD be monitored to allow for the early detection and treatment of secondary malignant disease.

Binary and WHO dysplasia grading systems for the prediction of malignant transformation of oral leukoplakia and erythroplakia: a systematic review and meta-analysis.

OBJECTIVES: The aim of this systematic review was to examine the evidence of the binary histologic grading system capacity for predicting malignant transformation and to compare it with that of the WHO systems. MATERIAL AND METHODS: A systematic review was conducted, using PubMed, EMBASE, LILACS, Web of Science, Scopus, and LIVIVO databases without any language or timeframe restrictions. Studies were included if they compared the binary and the WHO histologic grading systems in the prediction of malignant transformation of oral epithelial dysplasia (OED). RESULTS: The capacity of the WHO and binary grading systems to predict malignant transformation ranged from 16 to 80% and from 5 to 80%, respectively. The pooled malignant transformation rate of lesions classified as severe dysplasia or carcinoma in situ by the WHO grading was 40% (95% confidence interval (CI), 0.02-0.87; I2 = 92%; P = 0.00), while the corresponding value for lesions classified as high-risk by the binary grading system was 31% (95% CI, 0.00-0.84; I2 = 97%; P = 0.00). Overall, there was no significant difference in prognostication accuracy between the WHO and the binary systems (odds ratio = 2.02; 95% CI, 0.88-4.64). CONCLUSIONS: Although some studies suggest that the binary system is associated with lower inter-rater variability when grading OED, the evidence remains inconclusive on whether this system is superior to that of the WHO at predicting malignant transformation. CLINICAL RELEVANCE: The reproducibility of the binary system has the potential to be better for prognostic purposes. However, there is no high-quality evidence to confirm if this advantage may assist clinicians in decision-making.

Avaliação da Aplicação dos Filtros de Imagem na Detecção de Fraturas Radiculares / Evaluation of Enhacement Filters in the Detection of Vertical Root Fractures

Objetivo: Avaliar a acurácia, sensibilidade e especificidade de diferentes filtros do software Cliniview™ (versão 10.1) em radiografias periapicais digitais na detecção de fraturas radiculares verticais em dentes unirradiculares. Material e Métodos: Foram utilizados 31 dentes humanos recém-extraídos divididos em dois grupos: controle (CTL) e fraturado (FTR), constituídos por 15 e 16 dentes, respectivamente. Realizou-se o tratamento endodôntico dos dentes para posterior desobturação de 2/3 da raiz e confecção dos pinos metálicos. Após cimentação dos pinos, as raízes dos dentes grupo FTR foram fraturadas na máquina de ensaio (Instron). As radiografias periapicais digitais foram obtidas em todos os dentes com sistema digital Express™. As radiografias originais e com aplicação dos filtros (inversão na escala de cinza, hot, nitidez 1, vertical e vertical + horizontal) foram salvas e avaliadas por dois especialistas. Após as análises, foram calculados os valores de sensibilidade, especificidade, preditivo positivo, preditivo negativo e acurácia da radiografia periapical digital com e sem a aplicação dos filtros. Resultados: Considerando os dois examinadores, os maiores valores de acuraria, sensibilidade e especificidade para as imagens originais foram de 85,2%, 100% e 95,2% respectivamente. Para as radiografias com aplicação de filtro, os maiores valores de acurácia, sensibilidade e especificidade foram de 82,6%, 71,4% e 87,5%, respectivamente. Conclusão: O uso de filtros não aumentou os valores de acurácia, sensibilidade e especificidade das radiografias periapicais digitais para a detecção das fraturas radiculares verticais. De fato, pelo contrário, em alguns casos, o diagnóstico piorou.

Objective: To evaluate the accuracy, sensitivity, and specificity of different Cliniview™ (version 10.1) software filters in digital periapical radiographs for the detection of vertical root fractures in single-rooted teeth. Materials and Methods: Thirty-one human teeth freshly extracted were divided into two groups: control (CTL) and fractured (FTR), constituted by 15 and 16 teeth respectively. The endodontic treatment of the teeth was performed and followed by desobturation of ⅔ of the root canal and the metallic posts confection. After the cementation of the posts, the fractures were made using the universal test machine (Instron) only in the FTR group. The digital periapical radiographs were performed in all the teeth using the ExpressTM digital system. The original radiographs and the ones with applied filters (gray scale, hot, sharpness 1, vertical and vertical + horizontal) were saved and evaluated by two specialists. After the analysis, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the digital periapical radiographs with and without the application of filters were calculated. Results: Taking into consideration the two examiners, the highest accuracy, sensitivity and specificity values for the original images were 85,2%, 100% and 95,2% respectively. For the radiographs with applied filters, the highest accuracy, sensitivity and specificity values found were of 82,6%, 71,4% and 87,5%, respectively. Conclusion: The use of filters did not increase the accuracy, sensitivity and specificity values of the digital periapical radiographs for the detection of VRF. In fact, on the contrary, for some cases, the diagnosis became worse.

Mesenchymal Stem Cell Marker Expression in Periapical Abscess.

INTRODUCTION: There is evidence that acute periapical lesions present a greater potential for cyst formation. Recently, it was found that these lesions have cells with characteristics of pluripotent stem cells, which may influence cyst development. However, a more complete phenotype investigation of stem cells in a specific sample of periapical abscesses is required. The aim of this study was to analyze the immunohistochemical expression of mesenchymal stem cell (MSC) markers in periapical abscesses and to evaluate differences in their expression in relation to acute and chronic periapical lesions. METHODS: Immunohistochemistry was used to access MSC marker expression (CD44, CD73, and CD105) in samples of periapical abscesses (n = 10), granulomas (n = 10), cysts (n = 10), and apical papillae (n = 10). Immunohistochemical expression was evaluated by a quantitative scoring system. The chi-square test was used to assess the association between MSC marker expression and the histopathological diagnosis at a 5% significance level. RESULTS: CD44 and CD73 immunostaining was observed in mesenchymal cells located in the outer portion of the abscess and periapical cyst specimens. CD105 immunoexpression was found predominantly in mesenchymal and vascular endothelial cells of the lesions studied. MSC marker expression was higher in the periapical abscesses, with a significant association between MSCs and the histopathological diagnosis of an abscess (P < .05). CONCLUSIONS: The periapical region is a rich source of MSCs. The greater presence of MSCs in periapical abscesses found in this study could hold an important clue into understanding the pathological pathway of periapical cyst formation.

Contribution of cone-beam computed tomography in the decision of surgical management for bone lesions of the maxillofacial region.

The aim of this study was to evaluate the contribution of cone-beam computed tomography (CBCT) in the decision of surgical management for bone lesions of the maxillofacial region. It is a retrospective cross-sectional observational study that includes a sample of panoramic radiography (PR) and CBCT from patients with some type of bone lesion in the maxillofacial region. PR and CBCT images were evaluated by three previously assessed examiners, specialists in oral and maxillofacial surgery. Each image was evaluated randomly, and a surgical procedure was suggested, initially in PR and then in CBCT. The obtained results were submitted to the McNemar test to evaluate the frequencies of changes in the surgical management between the first and the second evaluation in PR and CBCT, and intra-examiner and inter-examiner agreements were analyzed by the Cohen's kappa test. The level of significance was set at 5% (p < 0.05). Intra-examiner agreement increases when CBCT is used. Inter-examiner agreement was low, independently of the evaluated exam, which shows that the choice of treatment plan is examiner-dependent and not exam-dependent. CBCT increases the certainty of the professional in the evaluation of the bone lesions of the maxillofacial region; however, it does not change the indication of the treatment type.

Effect of Alendronate on Bone Microarchitecture in Irradiated Rats With Osteoporosis: Micro-CT and Histomorphometric Analysis.

PURPOSE: The aim of the present study was to evaluate the effect of alendronate (ALN) on the bone microarchitecture of irradiated rats with estrogen deficiency, using microcomputed tomography (micro-CT) and histomorphometric analysis. MATERIALS AND METHODS: Forty adult Wistar rats were subjected to ovariectomy and randomly divided into the following groups: control (CON), ALN, irradiated (IRR), and ALN/irradiated (ALN/IRR). Approximately 50 days after ovariectomy, the hind limbs of the rats in the IRR and ALN/IRR groups were irradiated with 15 Gy of x-radiation. The rats were euthanized 7 and 30 days after irradiation. The bone microarchitecture was analyzed using micro-CT and histomorphometry. The bone microarchitecture was evaluated using the Mann-Whitney U test, analysis of variance, and the post hoc Tukey test, with statistical significance set at 5%. RESULTS: Irradiation had increased the thickness of the cortical bone at 7 days (P < .05) and also decreased the number of trabeculae per unit length and increased the average distance between the trabeculae (P < .05) at 30 days. ALN inhibited the deleterious effect of x-radiation, preventing the distance between the trabeculae from increasing and the number of trabeculae per unit length from decreasing (P < .05). CONCLUSIONS: The present results have demonstrated that the initial effect of ALN could be positive, because it checked the deleterious action in the bone tissue submitted to x-radiation.

Chondroblastic osteosarcoma mimicking periapical abscess.

CASE REPORT: The present report describes a case of chondroblastic osteosarcoma in the periapical region of teeth #29, #30, and #31 of an 18-year-old male. Clinical history showed self-reported discomfort in the right posterior gingiva for over a month. Physical examination showed a small expansion and redness of the right mandibular buccal and lingual cortical plates, but no signs of pain or inflammation were observed. All the teeth responded positively to pulp sensibility. Periapical and panoramic radiographs showed slight periapical radiolucency in the roots of teeth #29 and #30, clear periodontal ligament space widening, and evident loss of lamina dura. Incisional biopsy was performed, and based on microscopic findings the diagnosis of chondroblastic osteosarcoma was confirmed. CONCLUSIONS: Non-endodontic diseases associated with tooth root apex, such as chondroblastic osteosarcoma, should be included in differential diagnosis of jaw lesions that resemble periapical abscess.

20-year Follow-up of Recurrent Glandular Odontogenic Cyst Mimicking a Periapical Lesion.

Periapical lesions usually are caused by root canal infection; nevertheless, other pathologies may eventually involve the tooth apex, making the correct diagnosis more difficult. Glandular odontogenic cysts (GOCs) are uncommon and, despite their cystic nature, may present an aggressive behavior and a high recurrence rate. This report describes a recurrent GOC mimicking a periapical lesion that was followed up for 20 years. A 45-year-old woman described tooth discomfort for several years in the anterior region of the mandible that was not exacerbated during eating or occlusion. Clinical examination revealed no signs of swelling, redness, or inflammation in the gingival or surrounding soft tissue. Nevertheless, periapical radiography showed a well-defined large radiolucent lesion in the periapical region of teeth #22, #23, #24, and #25. The pulp test confirmed that all these teeth were vital. An incisional biopsy was performed, and with the histopathological diagnosis of an odontogenic cyst, the lesion was enucleated surgically. After recurrence, the extensive periapical multilocular lesions were again surgically removed. Based on the microscopic findings, the final diagnosis was GOC. One year later, there were no signs of recurrence. GOCs associated with the root apex may mimic periapical inflammatory diseases. Clinical, radiographic, and histopathological findings are essential for the diagnosis of inconclusive radiolucent findings in the periapical region. Biopsy specimens should be sent to a specialized oral pathology laboratory.

Chondroblastic osteosarcoma mimicking periapical abscess

Abstract Lesions of non-endodontic origin may mimic periapical abscess. Osteosarcoma is a rare malignant lesion. Case report The present report describes a case of chondroblastic osteosarcoma in the periapical region of teeth #29, #30, and #31 of an 18-year-old male. Clinical history showed self-reported discomfort in the right posterior gingiva for over a month. Physical examination showed a small expansion and redness of the right mandibular buccal and lingual cortical plates, but no signs of pain or inflammation were observed. All the teeth responded positively to pulp sensibility. Periapical and panoramic radiographs showed slight periapical radiolucency in the roots of teeth #29 and #30, clear periodontal ligament space widening, and evident loss of lamina dura. Incisional biopsy was performed, and based on microscopic findings the diagnosis of chondroblastic osteosarcoma was confirmed. Conclusions Non-endodontic diseases associated with tooth root apex, such as chondroblastic osteosarcoma, should be included in differential diagnosis of jaw lesions that resemble periapical abscess.

Systemic corticosteroid in the treatment of a 9-year-old boy with oral mucous membrane pemphigoid: a case report / Utilização de corticóide sistêmico no tratamento do penfigóide benigno das membranas mucosas em uma criança de 9 anos de idade: um relato de caso

Objective: The aim of this report is present a rare case of oral Mucous Membrane Pemphigoid (MMP) in a 9-year-old-boy successfully treated with low doses of systemic corticosteroid. Case description: A 9-year-old boy was referred to our service with the complaint of painful gingiva and generalized burning mouth sensation over 1 year. Intraoral examination revealed desquamative lesions affecting the entire attached gingiva of both the maxilla and the mandible. After the incisional biopsy the MMP diagnosis was confirmed, and the patient was initially treated with dexamethasone 0,1mg/Ml mouth rinse twice daily for 24 weeks. Due the difficulty in eating and the presence of persistent large oral lesions, systemic prednisone 20 mg (1 mg/Kg) was prescribed for 4 weeks with a 5 mg gradual reduction per week over 3 weeks. After initiating the systemic corticosteroid therapy, the patient showed total regression of the lesions, and no indication of recurrence has been observed in the past 6 months. Conclusion: There is no cure for MMP; however, treatment can provide complete and long-lasting remission. Based on this premise, it is plausible to consider not only topical but also low doses of systemic corticosteroids in resistant cases of oral MMP, even in children. These measures could improve the quality of life of these patients by reducing pain and, consequently, improving the child's eating behavior.

Objetivo: O objetivo deste relato é apresentar um caso raro de Penfigóide Benigno das Membranas Mucosas (PBMM) em um menino de 9 anos de idade tratado com sucesso com baixas doses de corticosteróide sistémico. Relato de caso: Um menino de 9 anos de idade foi encaminhado ao nosso serviço com a queixa de gengiva dolorida e sensação de queimação na boca há aproximadamente 1 ano. Ao exame físico intraoral constatou-se a presença de lesões descamativas que afetavam toda a gengiva inserida, tanto na maxila quanto na mandíbula. Após a realização de uma biópsia incisional o diagnóstico de PBMM foi confirmado, e o paciente foi inicialmente tratado com elixir de dexametasona 0,1mg / ml duas vezes por dia durante 24 semanas. Devido a dificuldade em comer e a presença de grandes lesões orais persistentes, foi prescrito prednisona sistêmica 20 mg (1 mg / Kg) por 4 semanas com uma redução gradual de 5 mg por semana durante 3 semanas. Depois de iniciar a corticoterapia sistêmica, o paciente apresentou regressão total das lesões, e nenhum sinal de recorrência tem sido observado nos últimos 6 meses. Conclusão: Não há cura para o PBMM; no entanto, o tratamento pode proporcionar a remissão completa e de longa duração. Com base nesta premissa, é plausível considerar a terapia tópica, mas também a utilização de corticosteroides sistêmicos em casos resistentes de PBMM oral, mesmo em crianças. Estas medidas poderiam melhorar a qualidade de vida desses pacientes, reduzindo a dor e, consequentemente, melhorando a alimentação da criança.

Estudo in vitro do padrão de crescimento e proliferação celular de pré-osteoblastos humanos com bio-oss® e genox® / In vitro study of growth and proliferation of human pre-osteoblast on bio-oss® and genox®

Objetivo: O presente trabalho avaliou o padrão de crescimento, o índice de proliferação celular e morfologia de pré-osteoblastos humanos cultivados com Bio-Oss® e GenOx®. Material e Método: Pré-osteoblastos humanos MC3T3-E1 foram cultivados em contato com os biomateriais por 1, 24 e 72horas para avaliação da proliferação celular, medido com o teste colorimétrico MTS. Para a avaliação do padrão de crescimento e da morfologia celular, as células foram cultivadas por 24 e 72 horas, respectivamente e avaliadas sob microscopia de contraste de fase e microscopia eletrônica de varredura (MEV). Para verificação de diferenças no crescimento celular entre os grupos foi utilizado o teste one-way de ANOVA, sendo considerados significantes valores de p<0,05. Resultados: A proliferação celular foi maior na primeira hora nas amostras em contato com os biomateriais em comparação ao grupo controle. Nos períodos de 24 e 72 horas de cultivo celular, a curva de crescimento não mostrou diferença estatisticamente significante entre os grupos (p>0.05). Na microscopia de contraste de fase observou-se que as células cresceram em proximidade aos biomateriais, iniciando a formação da monocamada de maneira semelhante. Quando analisadas no MEV, as células cultivadas sobre os biomateriais apresentaram-se com formato fusiforme e núcleo arredado. Conclusão: Com a comparação do comportamento biológico de Bio-Oss® e GenOx®, realizada in vitro neste estudo, pôde-se observar que apesar das diferenças físico-químicas, o padrão, índice de crescimento e morfologia celular de Bio-Oss® e GenOx® se mostraram semelhantes, e que ambos materiais são biocompatíveis e representam uma boa opção como substitutos ósseos.

Objective: The present study aimed to evaluate the growth pattern, cell proliferation index and morphology of human preosteoblasts cultured with Bio-Oss® and GenOx®. Material and Methods: MC3T3-E1 human pre-osteoblasts were cultured in contact with biomaterials for 1, 24 and 72 hours for the cell proliferation assay with the colorimetric test MTS. For the growth pattern and cell morphology analysis, the cells were cultured for 24 and 72 hours, respectively, and evaluated under phase contrast microscopy and scanning electron microscopy. To verify differences in cell growth among the groups, the one-way ANOVA test was used (p <0.05). Results: In the first hour of cell culture the cell proliferation was pronounced in samples in contact with the biomaterials. At 24 and 72 hours of cell culture, no significant differences between the groups was observed in respect of cell proliferation. In phase contrast microscopy it was noted that the cells grew in proximity to the biomaterials, initiating the formation of a monolayer. When analyzed in the scanning electron microscopy, the cells cultured on the biomaterials presented a fusiform morphology and a round nucleus. Conclusion: Despite the physico-chemical differences between Bio- Oss® and GenOx®, these two biomaterials presented a similar growth index and cell morphology analysis, showing that both biomaterials are biocompatible and represent a good choice as bone substitutes.

Cytotoxic Effect of Erythroxylum suberosum Combined with Radiotherapy in Head and Neck Cancer Cell Lines.

The mouth and oropharynx cancer is the 6th most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as "cabelo-de-negro". The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas.

Cytotoxic Effect of Erythroxylum suberosum Combined with Radiotherapy in Head and Neck Cancer Cell Lines

Abstract The mouth and oropharynx cancer is the 6th most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as "cabelo-de-negro". The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas.

Resumo O câncer de boca e de orofaringe emerge como o 6º tipo de câncer mais comum no mundo. O tratamento pode envolver cirurgia, quimioterapia e radioterapia. Mais de 50% das drogas com atividade de combate ao câncer foram isoladas de fontes naturais, tais como a Catharanthus roseus e a epipodofilotoxina, isolada de Podophyllum. O maior desafio é maximizar o controle da doença, enquanto minimiza a morbidade e toxicidade para os tecidos normais circundantes. O Erythroxylum suberosum é uma planta comum no bioma Cerrado brasileiro e é popularmente conhecida como "cabelo-de-negro". O objetivo deste estudo foi avaliar a citotoxicidade dos extratos da planta Erythroxylum suberosum do bioma Cerrado brasileiro, associados à radioterapia em linhagens celulares humanas de carcinomas de língua e de hipofaringe. As células foram tratadas com os extratos aquoso, etanólico e hexânico do Erythroxylum suberosum e irradiadas com 4 Gy, 6 Gy e 8 Gy. A citotoxidade foi avaliada pelo ensaio de MTT e a absorvância foi medida a 570 nm em uma leitora Beckman. A cisplatina, quimioterápico padrão, foi utilizada como controle positivo. O uso de extratos de Erythroxylum suberosum mostrou potencial efeito radiosensibilizante in vitro no câncer de cabeça e pescoço. O efeito da citotoxicidade nas linhagens foi de forma não seletiva e muito semelhante ao efeito da quimioterapia padrão. O extrato aquoso de Erythroxylum suberosum, combinado com radioterapia, foi o extrato mais citotóxico para os carcinomas de língua e hipofaringe, associados à radioterapia.

Altered ß-catenin expression in oral mucosal dysplasia: a comparative study.

OBJECTIVE: The current study aimed to investigate the ß-catenin expression in oral leukoplakia (OL) with different degrees of epithelial dysplasia and normal oral mucosa. MATERIAL AND METHODS: Formalin-fixed, paraffin-embedded tissue samples of 39 OL (mild dysplasia n=19, moderate dysplasia n=13, and severe dysplasia n=7), and 10 normal oral mucosa (control group) were submitted to immunohistochemical reactions to anti-ß-catenin primary antibody. A qualitative ß-catenin analysis was performed based on the percentage of positive cells. The cellular location and the epithelial layer were also considered. The Chi-square test and the Fisher's exact test were used to verify possible differences in the ß-catenin expression among the OL groups. A p-value of <0.05 was considered statistically significant. RESULTS: Membranous expression of ß-catenin in parabasal and basal layers was gradually lost in the higher degrees of epithelial dysplasia. In normal oral mucosa, ß-catenin was detected only in the cytoplasmic membrane. However, a significant increase in cytoplasmic ß-catenin could be observed between mild and moderate dysplasia (Fisher Exact test - p<0.001) and between mild and severe dysplasia (p<0.001). CONCLUSIONS: The ß-catenin cytoplasmic expression observed in this study may represent the initial stage of modifications in the E-cadherin-catenin complex, along with morphological cellular changes.