Análise fractal do osso mandibular e a ocorrência de osteorradionecrose: um estudo transversal com grupo controle / Fractal analysis of mandibular bone and occurrence of osteoradionecrosis: a cross-sectional study with control group

A radioterapia (RT) é amplamente utilizada para o tratamento do câncer em região de cabeça e pescoço. A osteorradionecrose (ORN) é uma das mais severas complicações desta modalidade terapêutica. Todos os pacientes tratados com radioterapia são considerados de alta risco para o desenvolvimento da ORN, devido à falta de fatores preditivos dessa comorbidade, a morbidade e a imprevisibilidade da resposta ao tratamento. A análise fractal é utilizada para descrever a complexidade de uma estrutura e avaliar anormalidades e gravidade de distúrbios da arquitetura óssea. Entretanto, poucos estudos utilizaram a análise fractal para avaliar a estrutura óssea de pacientes submetidos à RT em região de cabeça e pescoço. Portanto, o objetivo deste trabalho foi avaliar a dimensão fractal (DF) e lacunaridade do osso mandibular em indivíduos submetidos à RT para tratamento de câncer de cabeça e pescoço, comparando aqueles desenvolveram ORN (grupo caso) com aqueles que não desenvolveram ORN (grupo controle). O estudo foi aprovado pelo Comitê de Ética em Pesquisa da UFMG (CAAE 30560820.9.0000.5149). É um estudo transversal com grupo controle, no qual 34 pacientes foram incluídos e divididos em grupo caso (com ORN, n=17) e grupo controle (sem ORN, n=17). Uma radiografia panorâmica digital, adquirida após o término da RT, foi avaliada para cada paciente. A DF e lacunaridade do osso mandibular foram determinados usando o software ImageJ. Foi realizada análise estatística bivariada, bem como análise da curva ROC. A significância foi estabelecida em p< 0,05. Os valores médios de DF e lacunaridade não foram significativamente diferentes entre os grupos. A área sob a curva para DF foi de 0,576 e para lacunaridade foi de 0,626. O ponto de corte encontrado para DF foi ≤1,1736 e >0,4155 para lacunaridade, os quais classificaram corretamente casos e controles. A maioria dos pacientes com ORN (92.9%) tiveram DF> 1.1736 e todos os controles tiveram DF≤ 1.1736 (p< 0.001). Para a lacunaridade, a maioria dos pacientes com ORN (71.4%) apresentaram valor > 0.4155 e todos os controles tiveram valor ≤ 0.4155 (p< 0.001). Em conclusão, os pontos de corte da DF e lacunaridade do osso mandibular, estabelecidos pela análise de radiografias panorâmicas, puderam classificar corretamente pacientes com ORN e sem ORN.

Radiotherapy (RT) is widely used in the treatment of head and neck cancer. Osteoradionecrosis (ORN) is one of the most severe complication of this therapeutic modality. All patients treated with RT are considered at high risk for the development of ORN, due to the lack of predictive factors for ORN, the morbidity, and the unpredictable response to treatment. Fractal analysis is used to describe the complexity of a structure and to assess abnormalities and the severity of bone architecture disorders. However, few studies have used fractal analysis to assess the bone structure of patients undergoing RT in head and neck region. Therefore, the aim of this study was to evaluate the FD and lacunarity of the mandibular bone in individuals who received radiation therapy for HNC, comparing those who had developed ORN to those who had not developed ORN (control group). The study was approved by the Research Ethics Committee of the Universidade Federal de Minas Gerais (certificate number: 30560820.9.0000.5149). This is a cross-sectional study with a control group and thirty-four patients were included and divided into case group (with ORN, n=17) and control group (without ORN, n=17). One digital panoramic radiograph acquired after the end of RT was evaluated for each patient. FD and lacunarity of the mandibular bone were determined using ImageJ software. Bivariate statistics was done, as well as ROC curve analysis. Significance was stablished at p< 0.05. The mean FD and lacunarity values were not significantly different between the groups. The area under the curve for FD and lacunarity were 0.576 and 0.626, respectively. The cut-off point found for FD was ≤1.1736 and >0.4155 for lacunarity, allowing us to correctly classify cases and controls. Most participants in the case group (92.9%) had a FD >1.1736 and all participants in the control group had a FD ≤ 1.1736 (p < 0.001). For lacunarity, most individuals in the case group (71.4%) had a value >0.4155 and all participants in the control group had a value ≤0.4155 (p <0.001). Conclusion: The cut-off values of FD and lacunarity of mandibular bone, assessed on panoramic radiographs, differ between patients with and without ORN.

Differential diagnoses of solitary and multiple pigmented lesions of the oral mucosa: Evaluation of 905 specimens submitted to histopathological examination.

BACKGROUND: The aim was to analyze the frequency, clinical and demographic features of solitary and multiple/diffuse oral pigmented lesions submitted to histopathological examination, and to summarize the features that guide the clinical differential diagnosis. METHODS: Clinical and demographic data were retrieved from biopsy records and descriptive statistics were performed. RESULTS: Nine hundred and five (0.51%) oral pigmented lesions were retrieved among 177 356 specimens, being 95.9% solitary and 4.1% multiple/diffuse lesions. Regardless the overlapping clinical presentation, age, site, association with amalgam restoration, and a nodular appearance may help in the clinical differential diagnosis of solitary oral pigmentations. Patient's habits, site, and systemic signs and symptoms are helpful in the clinical differential diagnosis of multiple/diffuse lesions. CONCLUSIONS: Oral pigmented lesions are a rare diagnosis in oral pathology and solitary lesions are more commonly submitted to biopsy. Some key features help in the differential diagnosis, though biopsy can be warranted in doubtful cases.

Benign connective and soft-tissue neoplasms of the oral and maxillofacial region: Cross-sectional study of 1066 histopathological specimens.

BACKGROUND: Benign connective and soft-tissue neoplasms (CSTNs) are unusual in the head and neck region. The aim of the present study was to evaluate the demographic and clinicopathological features of these neoplasms. METHODS: A cross-sectional study was conducted of cases diagnosed as benign CSTNs, with data collected from biopsy records. The chi-square test was used. A p-value <0.05 was considered indicative of statistical significance. RESULTS: Among the 38 119 specimens, 1066 (2.79%) were benign CSTNs: 369 fibroblastic/myofibroblastic, 250 adipocytic, 179 vascular, 130 neural, 94 osseous/cartilaginous, 19 muscular, and two fibrohistiocytic. Most patients were female (62.8%) and white-skinned (45.8%). Mean age was 42 years. The tongue (25.2%) was the most affected site for extraosseous neoplasms. CONCLUSION: This study had the largest sample of benign oral and maxillofacial CSTNs. Although these tumors have similar clinical features, the characterization and differentiation detailed here may help clinicians with regards to the correct diagnosis.