Journal of Dental Medicine

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Nucleolar organizer regions (NORs) are loops of rDNA, which in human, occur on the short arms of five acrocentric chromosomes, namely, 13, 14, 15, 21 and 22. NORs are usually demonstrated by binding If their associated proteins (NORAPsO to silver (Ag+) ions. The reaction is called AgNORs. It has been determined that, the number and the size of NORs is related to the proliferative activity and grade of malignancy. This has led to the application of AgNOR method to a wide range of diagnostic problem cases, including breast, salivary glands and lung malignant neoplasms.The purpose of this study was to determine the value of AgNOR method in assessment of the grade of malignancy in non- Hodgkin's lymphoma of head & neck, which often is difficult and essentially important in relation to the prognosis and treatment.41 cases of paraffin embedded specimens of NHL, which were classified by working formulation system,were selected and then AgNORs method was applied on them.AgNORs were enumerated for all 41 cases of NHL (Standard Crocker).The mean AgNORs in 11 cases of low grade 15 cases of intermediate grade and 15 cases of high grade NHL was 1.66 (SEM= 0.098), 2.25 (SEM= 0.084) and 5.19 (SEM= 0.11), respectively.In analysis of variance and multiple comparisons, a significant difference was found between the three groups of NHL (P<0.000I).It is concluded that the AgNORs, as a reliable method, could be used in differentiation of low,intermediate and high grade NHL in head and neck area.

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Melanoma is a malignant tumor that originates from melanocyte cells. Its oral type is rare. The goal of this investigation was to determine the prevalence of oral malignant melanoma in Iran, as determined by age, sex and location. This research reviewed 623 cases of oral and non-oral malignant melanoma in Immam-Khomeini hospital, Mearaj cancer institute and department of oral pathology of dental faculty, Tehran University of Medical Sciences in a period of 19 years from 1981-1999. The results showed that 54 cases of biopsy lesions were melanoma of oral cavity that included 7.8% of these lesions. The mean age incidence of oral melanoma was 55.5(between 26-86 years). The most prevalent sites were palate (37.1%) and alveolar mucosa (20.4%) and less common sites included floor of mouth. buccal mucosa and tongue.

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Cancer is considered as one of human's complications, particularly in oral and maxillofacial region which leads to undesirable effects and sometimes endangers individual's life. The aim of this study was to investigate the frequency of maxillofacial malignant tumors, during 13 years, (1985- 1998),in Hamedan. Three hundred and eighty - six records of biopsies were selected from the private files of physicians, 7 private and governmental pathological centers and other educational and research organizations in Hamedan. After observing the samples by oral pathologist, they were presented as the statistical population for this retrospective study. The highest rate of biopsies was observed in the sixth (42.7%), seventh (39.6%) and third (10.6%) decades. The average age was 43.5 years, for women and 1.52 45.5 for men. The ratio of men to women was . The oldest patient was a 91- year - old man with malignant melanoma, while the youngest was a 3-year-old girl with Burkit lymphoma. The commonest site of involvement was nasal region (17.3%) and the anterior neck triangle showed the least common tumoral site (2.3%). The commonest tumor, observed in this study, was BBC (41.4%) and the least common was malignant fibrous histocytoma (0.2%). Baso cellular and epidermoid carcinomas have been the commonest cancers in this investigation, while lymphoma and salivary galnd cancers have been placed as the second ones. The results of this study showed that the lower lip and tongue are considered as the commonest sites for cancer.