Ameloblastomas are epithelial odontogenic tumours that, although benign, are locally invasive and may exhibit aggressive behaviour. In the tumour microenvironment, the concentration of oxygen is reduced, which leads to intratumoral hypoxia. Under hypoxia, the crosstalk between the HIF-1α, MMP-2, VEGF, and VEGFR-2 proteins has been associated with hypoxia-induced angiogenesis, leading to tumour progression and increased invasiveness. This work showcases 24 ameloblastoma cases, 10 calcifying odontogenic cysts, and 9 dental follicles, used to investigate the expression of these proteins by immunohistochemistry. The anti-HIF-1α, anti-MMP-2, anti-VEGF, and anti-VEGFR-2 primary antibodies are used in this work. The results have been expressed by the mean grey value after immunostaining in images acquired with an objective of 40×. The ameloblastoma samples showed higher immunoexpression of HIF-1α, MMP-2, VEGF, and VEGFR-2 when compared to the dental follicles and calcifying odontogenic cysts. Ameloblastomas show a higher degree of expression of proteins associated with intratumoral hypoxia and proangiogenic proteins, which indicates the possible role of these proteins in the biological behaviour of this tumour.

Central giant cell granuloma (CGCG) is a benign intraosseous lesion of the head and neck with potential for aggressive and locally destructive behaviour. Lesions of the maxilla tend to expand more than those of the mandible due to the thinner cortices and spongy tissue of this location. Surgical removal is the most common treatment; however, it may be disfiguring in aggressive cases, especially for lesions located in the maxilla. Alternative treatments, such as intralesional corticosteroid injections, have been performed with satisfactory results. We report a case of a 12-year-old female patient with a CGCG of the left maxilla that was treated with 40 doses of intralesional triamcinolone acetonide infiltrations combined with alendronate sodium and calcium carbonate. Clinical and imaging follow-up over 12 years demonstrates improvement in the patient's condition.

Introdução: Disseminação de infecções bucais e do trato respiratório são consequência de uma má higiene bucal ou ausência da mesma, influenciando no tempo de permanência do paciente no ambiente hospitalar. Objetivo: investigar e discutir qual o protocolo mais utilizado e eficaz descrito na literatura. Método: As estratégias de busca eletrônica foram desenvolvidas individualmente para cada um dos seguintes bancos de dados: LILACS, Scopus, Web of Science e Chrocrane. Foram encontrados 3476 estudos, após aplicação dos critérios de inclusão e exclusão, resultaram em 38 artigos entre 2016-2020, na língua portuguesa e inglesa. Resultados: Pode-se observar que o método mecânico mais eficaz e utilizado é a escovação dentária associada ou não a antissépticos ou pastas de dente. Dentre as substâncias químicas, a clorexidina, em várias concentrações, foi a mais citada e com ótimos resultados. Conclusão: Não houve uma padronização em relação à frequência diária que a higienização deve ser realizada.

Background Among cancers affecting the oral cavity, adenoid cystic carcinoma (ACC) is a relatively common malignant neoplasm. It has high rates of metastasis and recurrence and is associated with significant morbidity. During the progression of ACC, the oxygen concentration is reduced in specific areas of the tumour microenvironment, leading to intratumoural hypoxia. The expression of NOTCH1, a disintegrin and metalloproteinase 12 (ADAM-12), hypoxia-inducible factor 1 alpha (HIF-1α), and heparin-binding epidermal growth factor (HB-EGF) under hypoxic conditions has been implicated in invadopodia formation, tumour invasiveness, and metastasis. The aim of this study was to analyse the expression of these proteins to elucidate the mechanisms underlying ACC invasiveness. Methods Fifteen ACC samples and 10 normal-looking salivary gland (SG) samples were used to investigate the expression of these proteins by immunohistochemistry. Primary antibodies against NOTCH1, ADAM-12, HIF-1α, and HB-EGF were used. Results The immunoexpression of all proteins was higher in ACC samples than in SG samples (p < 0.05). Conclusions There was increased expression of proteins associated with hypoxia and tumour invasiveness in ACC samples, which indicates a possible role of these proteins in the biological behaviour of this tumour.

No abstract