Abstract Studies have reported changes in the epidemiological profile of patients with oral cancer in recent decades, especially regarding gender and age. This study aimed to evaluate a historical series of oral malignant lesions prevalence over six decades and define characteristics associated with the occurrence, mainly, of oral squamous cell carcinoma (OSCC). A retrospective review of histopathological records from 1953 to 2019 was conducted in three oral pathology laboratories in South Brazil about age, sex, anatomical site, clinical aspect, and histopathological diagnosis. Descriptive and analytical analyses were performed comparing the histopathological diagnoses with other variables. Multivariable logistic regression was applied to determine the associated predictors of OSCC. Of the 53,065 records available in the institutions, 986 were oral malignant tumors (including all malignant neoplasms), representing 1.86% of all diagnoses. The occurrence of OSCC in the 1960's was 80.0%, decreasing over time reaching the lowest percentage of cases in the 1990's (75.8%) and significantly increasing to 88.7% in the 2010s. Females had a lower chance than males of having OSCC independently of the decade (odds ratio=0.30, p<0.001). This was the same for older individuals compared to those younger than 40 years. No interactions between sex, age, and decade were observed. The number of diagnoses of oral malignant lesions increased over time, and the occurrence of OSCC varied. Older individuals and males had higher chances of having OSCC independently of the decade. Therefore, in this study sample, no changes were observed in the epidemiological profile over the years concerning these predictors.

Resumo Alguns estudos relataram mudanças no perfil epidemiológico dos pacientes com câncer bucal nas últimas décadas, principalmente quanto ao gênero e a idade. Este estudo teve como objetivo avaliar, em uma série histórica, a prevalência de todas as lesões malignas bucais ao longo de seis décadas e definir características associadas na ocorrência, principalmente, de carcinoma espinocelular (CEC). Um levantamento retrospectivo dos registros histopatológicos de 1953 a 2019 foi realizado em três laboratórios de Patologia Bucal no Sul do Brasil em relação à idade, gênero, sítio anatômico, aspecto clínico e diagnóstico histopatológico. Análises descritivas e analíticas foram realizadas comparando-se os diagnósticos histopatológicos com as outras variáveis. A regressão logística multivariada foi aplicada para determinar os possíveis preditores associados ao CEC. Dos 53.065 prontuários disponíveis nas instituições, 986 eram tumores malignos bucais (incluindo todas as neoplasias malignas), representando 1,86% de todos os diagnósticos. A ocorrência de CEC na década de 1960 foi de 80,0%, diminuindo ao longo do tempo, atingindo o menor percentual de casos na década de 1990 (75,8%) e aumentando significativamente para 88,7% na década de 2010. As mulheres tiveram menor risco de desenvolver CEC do que os homens, independentemente da década (OR=0,30, p<0,001). Este foi o mesmo para indivíduos com idade mais avançada em comparação com aqueles com menos de 40 anos de idade. Não foram observadas interações entre gênero, idade e década. O número de diagnósticos de lesões malignas bucais aumentou ao longo das décadas e a ocorrência de CEC variou. Indivíduos com mais de 40 anos e do sexo masculino tiveram maiores chances de ter CEC, independentemente da década analisada. Portanto, nessa amostra estudada, não foram observadas mudanças no perfil epidemiológico ao longo dos anos com relação a esses preditores.

Abstract Traditional guidelines for determining the prognosis of patients with head and neck squamous cell carcinoma (HNSCC) are used to make therapeutic decisions. However, only 50% of the patients had lived for more than five years. The present study aimed to analyze the correlation of traditional prognostic factors such as tumor size, histological grading, regional metastases, and treatment with the survival of patients with HNSCC. A total of 78 patients diagnosed with HNSCC were followed up for 10 years after diagnosis and treatment. The health status of the patients was tracked at four time points, and according to the evolution of the patients and their final clinical status, we performed a prognostic analysis based on the clinical outcomes observed during the follow-up period. The final study cohort comprised 50 patients. Most patients had tumors < 4 cm in size (64%) and no regional metastases (64%); no patients had distant metastases at the time of diagnosis. Most individuals had tumors with good (48%) and moderate (46%) degrees of malignancy. At the end of the follow-up period, only 14% of the patients were discharged, 42% died of the tumor, and 44% remained under observation owing to the presence of a potentially malignant disorder, relapse, or metastases. This analysis showed that traditional prognostic factors were not accurate in detecting subclinical changes or predicting the clinical evolution of patients.

Resumo O objetivo deste estudo foi investigar os níveis de TGFβ1 na saliva e a proliferação/maturação das células epiteliais da mucosa em paciente diabéticos e hipertensos. Neste estudo transversal, saliva estimulada e amostras de citologia exfoliativa de mucosa oral foram coletadas de um total de 39 pacientes que se apresentavam saudáveis (controle, n=10) ou com história de hipertensão arterial (HAS, n=9), diabetes mellitus (DM, n=10) ou ambos (DM+HAS, n=10). Taxa de fluxo salivar (SFR), níveis de TGFβ1 na saliva, AgNORs e maturação epitelial foram avaliados. Teste não-paramétrico de Kruskal-Wallis, seguido de comparação múltipla de Dunn e correlação de Spearman foram utilizados para as análises. SFR diminuiu significantemente em DM e DM+HAS (0,47±0,11 e 0,64±0,43 mL/min) quando comparado ao controle (1,4±0,38 mL/min). DM+HAS apresentou os maiores valores de concentração de TGFβ1 (24,72±5,89 pg/mL). Foi observada uma correlação positiva entre TGFβ1 e glicemia (R=0,6371; p<0,001) e uma correlação negativa entre TGFβ1 e saliva (R=-0,6162; p<0,001) e glicemia e SFR (R=-0,5654; p=0,001). Número de AgNORs e o padrão da maturação das células epiteliais foram similares entre os todos grupos. DM e DM+HAS apresentaram os menores valores de SFR, os quais foram correlacionados com o aumento nos níveis de TGFβ1. Apesar da maior secreção de TGFβ1, não foram observadas mudanças na morfologia ou proliferação das células epiteliais quando o paciente apresentava diabetes ou hipertensão.

Abstract The aim of this study was to investigate salivary levels of TGFβ1 and proliferation/ maturation of epithelial mucosa cells in diabetic and hypertensive patients. Design: in this cross-sectional study, whole stimulated saliva and oral mucosa exfoliative cytology specimens were collected from 39 patients that were healthy (control, n=10) or presented history of arterial hypertension (HAS, n=9), diabetes mellitus (DM, n=10) or both (DM+HAS, n=10). Salivary flow rate (SFR), TGFβ1 level in saliva, AgNORs and the epithelial maturation were evaluated. Non-parametric Kruskal-Wallis test, followed by Dunn’s multiple comparison post-test and the Spearman test correlation analysis were used. SFR showed a significant decreased in DM and DM+HAS (0.47±0.11 and 0.64±0.43 mL/min) when compared to control (1.4±0.38 mL/min). DM+HAS presented the highest value of TGFβ1 concentration (24.72±5.89 pg/mL). It was observed a positive correlation between TGFβ1 and glycaemia (R=0.6371; p<0.001) and a negative correlation between TGFβ1 and saliva (R=-0.6162; p<0.001) and glycaemia and SFR (R=-0.5654; P=0.001). AgNORs number and status of maturation of mucosa cells were similar for all conditions. DM and DM+HAS presented the lowest SFR, which correlated with increased TGFβ1 levels. Despite the higher TGFβ1 secretion it was not observed changes in the morphology or proliferation of epithelial cells when diabetes or hypertension was present.

Resumo O objetivo deste estudo foi avaliar a associação entre a expressão imunoistoquímica de E-caderina, N-caderina e Bmi-1, com os parâmetros clínicos e o grau de diferenciação em carcinomas espinocelulares bucais. Sessenta e cinco amostras foram selecionadas para a construção de um bloco de microarranjo tecidual, e a técnica de imunoistoquímica foi realizada para os diferentes marcadores. Uma análise semi-quantitativa das células tumorais positivas foi realizada por dois observadores calibrados e cegos (Kappa>0.75). Os testes estatísticos Mann-Whitney e Kruskal-Wallis foram utilizados para a análise dos dados e a correlação entre as variáveis foi investigada com o teste de Spearman. O nível de significância foi determinado em p <0.05. Observamos maior expressão de Bmi-1 em tumores localizados em palato (p <0.0001). Além disso, tumores pobremente diferenciados apresentaram maior quantidade de células positivas para Bmi-1 (p=0.0011). Não encontramos outras correlações ou associações significativas. Em conclusão, carcinomas espinocelulares pobremente diferenciados e localizados no palato apresentam maior marcação imunoistoquímica de Bmi-1, o que pode caracterizar a ativação do processo de transição epitélio-mesênquima nesses tumores.

Abstract The aim of this study is to evaluate the immunohistochemical expression of E-cadherin, N-cadherin and Bmi-1, and their association with clinical parameters and with the degree of histopathological differentiation in oral squamous cell carcinomas. 65 squamous cell carcinoma samples were used for constructing a tissue microarray block, and then immunohistochemistry was performed for different markers. A semi-quantitative analysis of the amount of positive tumor cells was performed by two blind and calibrated observers (Kappa>0.75). The statistical Mann-Whitney and Kruskal-Wallis tests were used to evaluate the data. The correlation between variables was investigated by the Spearman test, and the significance level set at p<0.05. We observed higher expression of Bmi-1 in tumors located in the palate (p<0.0001). In addition, poorly differentiated tumors had a greater amount of Bmi-1 positive cells (p=0.0011). Regarding the other correlations between variables, no significant associations were detected. In conclusion, poorly differentiated squamous cell carcinomas located in the palate have higher immunostaining of Bmi-1, which can characterize activation of the Epithelial-Mesenchymal Transition process in these tumors.

Abstract Objectives To evaluate the number of AgNORs per nucleus and the expression of Ki-67 at the tumor invasion front (TIF) in relation to clinical parameters (TNM), TIF classification and the prognosis of oral squamous cell carcinomas in an Uruguayan population. Material and Methods This study was conducted through a retrospective survey from 2000 to 2010 at the National Institute of Cancer Montevideo, Uruguay and included 40 patients. The samples were obtained from the resection of the tumor and the TIF was defined according with Bryne, et al.5 (1992). Expression of Ki-67 was assessed by the percentage of positive tumor cells and the AgNOR was recorded as the mean AgNOR (mAgNOR) and the percentage of AgNOR per nucleus (pAgNOR). All analyzes were performed by a blinded and calibrated observer. Results No statistically significant association was observed between immunostaining of Ki-67 and AgNOR with the different types of TIF, regional metastasis and patients prognosis, however it was observed an increase in Ki-67 expression associated with worse patient’s clinical staging, although not statistically significant. Conclusions Our results suggest that proliferation markers as AgNOR and Ki-67 are not prognostic markers at the tumor invasive front of carcinoma of oral squamous cell.

Resumo A maioria dos Departamentos de Patologia em todo o mundo têm um considerável acervo de tecidos embebidos em parafina e fixados em formalina, que são passíveis para análises moleculares. Este artigo apresenta os danos ao DNA que podem ocorrer se passos básicos não forem seguidos durante o processamento e armazenamento destas amostras. Além disso, procura estabelecer parâmetros para otimizar a qualidade e quantidade do DNA extraído de tecidos FFPE.

Abstract Most Departments of Pathology around the world have a considerable archive of formalin-fixed paraffin-embedded (FFPE) tissue suitable for molecular assessment. This article points out the potential DNA damage that may occur if basic steps are not followed during processing and storage of these samples. Furthermore, it hopes to establish parameters to optimize quality and quantity of DNA extracted from FFPE tissues.

Abstract To assess the immunocytochemical and immunohistochemical correlation of adhesion (E-cadherin) and cell differentiation (involucrin) molecules in oral leukoplakia and oral squamous cell carcinoma. Cytological samples and biopsies were obtained from male and female patients aged over 30 years with oral leukoplakia (n = 30) and oral squamous cell carcinoma (n = 22). Cell scrapings and the biopsy were performed at the site of the lesion and histological slides were prepared for the immunocytochemical analysis of exfoliated oral mucosal cells and for the immunohistochemical analysis of biopsy tissues using E-cadherin and involucrin. Spearman’s correlation and kappa coefficients were used to assess the correlation and level of agreement between the techniques. Immunostaining for E-cadherin and involucrin by both techniques was similar in the superficial layers of the histological sections compared with cell scrapings. However, there was no statistical correlation and agreement regarding the immunocytochemical and immunohistochemical expression of E-cadherin and involucrin in oral leukoplakia (R = 0.01, p = 0.958) (Kappa = 0.017, p = 0.92) or in oral squamous cell carcinoma (R = 0.26, p = 0.206) (Kappa = 0.36, p = 0.07). The immunoexpression of E-cadherin and involucrin in tissues is consistent with the expression patterns observed in exfoliated oral mucosal cells, despite the lack of a statistically significant correlation. There is an association of the histopathological characteristics of leukoplakia with the expression E-cadherin and of the microscopic aspects of oral squamous cell carcinoma with immunohistochemical expression of involucrin.

RESUMO Pesquisa exploratória documental de abordagem qualitativa cujo objetivo foi compreender como está se constituindo a formação do estudante de Odontologia em relação ao cuidado em saúde, a partir de uma atividade de ensino interdisciplinar ocorrida no segundo ano da formação do cirurgião-dentista. Foi realizado um levantamento retrospectivo do material produzido pelos estudantes do terceiro semestre do curso de Odontologia da Universidade Federal do Rio Grande do Sul, no Seminário de Integração IV, de 2006 a 2013. O corpus de análise foi formado por relatos de acompanhamento de pacientes e narrativas. Foram analisados 95 relatos de casos de pacientes e 67 narrativas pelo método da análise temática de conteúdo de Bardin. A análise do material resultou em 17 unidades de significação/categorias emergentes. A inclusão das narrativas no Seminário de Integração como estratégia metodológica de ensino na saúde trouxe a qualificação dos relatos e aproximou os estudantes do ser humano a ser cuidado, passando por sua queixa principal, história de vida e subjetividades. Currículos inovadores e integrados na área da saúde devem ser acompanhados permanentemente com base na experiência concreta nesta e em outras instituições de educação superior do País.

ABSTRACT This documentary exploratory research project with a qualitative approach aimed to understand how dental students are being trained in terms of healthcare, by means of an interdisciplinary teaching activity held in the second year of dental school. A retrospective survey was performed from the material produced by the students during the third semester of the dentistry course at the Federal University of Rio Grande do Sul, by means of the IV Integration Seminar held in 2006-2013. The analysis corpus consisted of reports featuring patient monitoring and narratives. We analyzed 95 patient case reports and 67 narratives using the thematic analysis method on Bardin content. Analysis of the material resulted in 17 meaning units/emerging categories. The inclusion of narratives in the Integration Seminar as a methodological strategy for health education facilitated the qualification of reports and brought students closer to the human beings under care, by means of exposing the students to the patients’ chief complaint, life history and subjective factors. The specific experiences of this study as well as those of other Brazilian educational institutions suggest that innovative and integrated curricula in the healthcare field must be implemented on a permanent basis.

Abstract The present study aimed to assess the rate of agreement between clinical and histopathological diagnoses and to report the frequency of completed forms for specimens that were subjected to histopathological examination and retrospectively examined. Data from 8,168 specimens submitted to histopathological examination were retrieved from the records. A total of 5,368 cases were included. Agreement was defined based on the definition of lesion nature according to its diagnostic category. Sensitivity, specificity, and positive and negative predictive values were calculated for each diagnostic category. The highest rate of agreement was observed for periapical lesions (92.6%), followed by potentially malignant disorders (90.1%) and non-neoplastic proliferative disorders (89.3%). Low rates of histopathological confirmation of the clinical impression were observed for mesenchymal tumors (25.0%) and cysts (44.2%). Sensitivity values were > 0.70 for all lesions, except for cysts (0.51). Specificity was relatively high, ranging from 0.97 to 1.00. The frequency of incomplete biopsy forms ranged from 16.8% (malignant tumors of oral mucosal epithelium) to 51.0% (nonspecific inflammatory reaction). The most frequently completed biopsy forms corresponded to epithelial malignant tumors (83.2%) and glandular inflammation (72.3%). In conclusion, there was an acceptable level of agreement. The low level of completeness of biopsy forms indicates little awareness about the relevance of gathering detailed information during clinical examination.

The aim of this study was to evaluate the effects of exposure to cell phone electromagnetic radiation on the frequency of micronuclei, broken eggs cells, binucleated cells, and karyorrhexis in epithelial cells of the oral mucosa. The sample was composed of 60 cell phone users, who were non-smokers and non-drinkers, and had no clinically visible oral lesions. Cells were obtained from anatomical sites with the highest incidence of oral cancer: lower lip, border of the tongue, and floor of the mouth. The Feulgen reaction was used for quantification of nuclear anomalies in 1,000 cells/slide. A slightly increase in the number of micronucleated cells in the lower lip and in binucleated cells on the floor of the mouth was observed in individuals who used their phones > 60 minutes/week. The analysis also revealed an increased number of broken eggs in the tongue of individuals owning a cell phone for over eight years. Results suggest that exposure to electromagnetic waves emitted by cell phones can increase nuclear abnormalities in individuals who use a cell phone for more than 60 minutes per week and for over eight years. Based on the present findings, we suggest that exposure to electromagnetic radiation emitted by cell phones may interfere with the development of metanuclear anomalies. Therefore, it is demonstrated that, despite a significant increase in these anomalies, the radiation emitted by cell phones among frequent users is within acceptable physiological limits.

OBJECTIVES: The aim of this study was to analyze the immunolabeling of two cell cycle protein regulators, p53 and p21WAF1, in non-dysplastic leukoplakias with different epithelial alterations: acanthosis, hyperkeratosis and acanthosis combined with hyperkeratosis, and compare them with dysplastic leukoplakias. MATERIAL AND METHODS: This was a prospective cohort study involving 36 patients with oral homogeneous leukoplakias. excisional biopsies were performed and the patients remain under clinical follow-up. The leukoplakias were divided into four groups: 6 acanthosis, 9 hyperkeratosis, 10 acanthosis combined with hyperkeratosis, and 11 epithelial dysplasias. Paraffin-embebeded sections were immunostained for p53 and p21WAF1. Five hundred cells from the basal layer and 500 from the parabasal layer were counted to determine the percentage of positive cells. A qualitative analysis was also carried out to determine the presence or absence of immunohistochemical staining in the intermediate and superficial layers. Groups were compared with ANOVA (p<0.05). Pearson's correlation coefficient was used to test for associations between the two markers, p53 and p21WAF1. RESULTS: No leukoplakia recurred and no malignant transformation was observed whitin a follow-up period of 3-6 years. The mean percentage of p53 staining in the basal and parabasal layers was similar in all groups. p21WAF1 staining differed between layers was as follows: in the basal, only 3 to 4% of cells were stained, while in the parabasal, between 16 and 28% of the epithelial cells were stained in the four different studied groups with no statistically significant difference (p>0.05). CONCLUSIONS: Our findings failed to differentiate the non-dysplastic lesions by means of p53 and p21WAF1 immunostaining, notwithstanding similar profiles between non-dysplastic and dysplastic leukoplakias were observed.

The purpose of the present paper was to describe the range of lesions histologically diagnosed in an oral pathology laboratory in southern Brazil. A retrospective study of 8,168 specimen analyses recorded between 1995 and 2004 was conducted. The records were retrieved from the Oral Pathology Laboratory, School of Dentistry, Federal University of Rio Grande do Sul, RS, Brazil. A total of 6,831 valid cases (83.63%) were examined. Of these, inflammatory lesions were the most common occurrences (n = 4,320; 63.24%). Benign and malignant tumors accounted for 7.66% (n = 523) and 1.9% (n = 130) of the occurrences, respectively. Significant associations were observed between nonneoplastic proliferative disorders and benign mesenchymal tumors in females, and between squamous cell carcinoma and leukoplakia in males. Most diagnoses were benign in nature and had an inflammatory etiology. The association of some demographic characteristics with the occurrence of lesions suggests that these characteristics should be considered in performing differential diagnoses.

Necrotizing ulcerative gingivitis is a relatively uncommon periodontal disease, characterized by ulceration, necrosis, pain and gingival bleeding. Factors often related to its occurrence include stress and systemic viral infections, such as those caused by cytomegalovirus and Epstein-Barr virus type 1, the latter being also considered the causative agent of infectious mononucleosis. This article aims to describe a clinical case of a female patient who presented with necrotizing ulcerative gingivitis associated with a clinical picture of infectious mononucleosis, as well as to review the literature concerning a possible correlation between these pathologies. This patient presented to our health care facility with necrotizing ulcerative gingivitis accompanied by lymphadenopathy, fever and prostration, after laboratory tests, Epstein-Barr virus type 1 infection was confirmed, as well as the co-occurrence of pathologies: necrotizing ulcerative gingivitis and infectious mononucleosis. Symptom remission in both disorders also occurred concomitantly, after instruction in plaque control measures and palliative medication for control of systemic symptoms. Therefore, although there is no scientific validation of an association between these two pathologies, it is imperative that all diagnostic alternatives be considered and investigated, in order to establish the therapeutic approach most appropriate to the patient.

La gingivitis ulcerativa necrótica es una enfermedad periodontal no común caracterizada por ulceración, necrosis, dolor y sangrado gingival. Los factores a menudo relacionados con su ocurrencia incluyen el estrés y las infecciones virales sistémicas como aquellas causadas por Cytomegalovirus y el virus Epstein-Barr tipo 1, donde este último es el agente causal de la mononuclerosis infecciosa. El objetivo de este trabajo fue describir el caso clínico de una mujer con gingivitis ulcerativa necrótica asociada a un cuadro clínico de mononucleosis infecciosa, así como hacer una revisión de la literatura concerniente a una posible correlación entre estas enfermedades. Esta paciente se presentó con una gingivitis ulcerativa necrótica acompañada de linfadenopatía, fiebre y postración después de las pruebas de laboratorio, donde se confirmó una infección por Epstein-Barr tipo 1 así como la ocurrencia conjunta de gingivitis ulcerativa necrótica y mononucleosis infecciosa. También se produjo una remisión concomitante de los síntomas en ambos trastornos después de la instrucción en medidas para el control de placas y una medicación paliativa para el control de los síntomas sistémicos. Por lo tanto, aunque no existió una validación científica de una asociación entre estas dos entidades, es imperativo que se consideren e investiguen todas las alternativas diagnósticas para establecer el enfoque terapéutico más apropiado para el paciente.

O objetivo deste estudo foi comparar procedimentos de medida da altura óssea histológica e morfométrica. O método mais freqüente de mensuração da altura óssea em estudos em animais são as medidas microscópicas. No entanto, tem limitada capacidade de identificar os níveis ósseos associados com os tecidos saudáveis e doença periodontal. Foram colocadas ligaduras no segundo molar superior esquerdo de 10 ratos machos Wistar com 60 dias de vida durante um período de 30 dias. Hemimaxilas direitas e esquerdas de 5 ratos foram processadas para a análise histológica (H), cortadas no sentido vestíbulo-lingual e coradas com HE. Hemimaxilas dos outros 5 ratos tiveram toda a matéria orgânica removida para análise morfométrica (M). Medidas histométricas da junção cemento-esmalte (JCE) à crista óssea alveolar foram realizadas. Fotografias padronizadas foram utilizadas na análise morfométrica. O teste t foi utilizado para amostras dependentes e independentes (alfa = 0,05%). As distâncias entre a JCE e a crista óssea na face palatina foram de 0,95 ± 0,25 e 1,07 ± 0,30 mm para H e M, respectivamente. As medidas vestibulares foram 0,92 ± 0,16 e 1,08 ± 0,35 mm para H e M. Os valores obtidos usando H e M para áreas sem ligadura foram 0,44 ± 0,15 e 0,47 ± 0,11 mm por lingual e 0,23 ± 0,08 e 0,41 ± 0,10 mm por vestibular, respectivamente. Não houve diferenças estatisticamente significativas entre os dois métodos na detecção da altura óssea associada à colocação de ligaduras em ratos.

The purpose of this study was to compare histologic and morphometric procedures of bone height measurement. Microscopic measurements are the most frequent methods in periodontal studies with animals, but have limited capacity to identify bone levels associated with both healthy tissues and periodontal disease. Ligatures were placed in the maxillary left second molars of 10 male 60-day-old Wistar rats for 30 days. Left and right maxillary sides of 5 rats were processed for histologic analysis (H), sectioned buccolingually, and stained with HE. The maxillae of the other 5 rats were defleshed and used for morphometric analysis (M). Histometric measurements from the cementoenamel junction to the bone crest were performed. Standardized photographs were used for morphometric analysis. The t test was used for dependent or independent samples (alpha = 0.05%). Distances from cementoenamel junction to bone crest were 0.95 ± 0.25 and 1.07 ± 0.30 mm for H and M, respectively. Buccal measurements were 0.92 ± 0.16 and 1.08 ± 0.35 mm for H and M. The values obtained using H and M for areas without ligatures were 0.44 ± 0.15 and 0.47 ± 0.11 mm for lingual measurements and 0.23 ± 0.08 and 0.41 ± 0.10 mm for buccal measurements. No significant differences were found between the two methods in the detection of bone height associated with the placement of ligatures in rats.

O objetivo deste estudo foi o de investigar a distribuição de linfócitos CD8+ e CD20+ em lesões inflamatórias periapicais. Para tanto foram estudados 90 casos entre abscessos crônicos, cistos abscedados e cistos inflamatórios. A tecnica de imunohistoquímica pelo método da estreptavidina-biotina foi utilizada para identificar linfócitos T citotóxico/supressor (CD8) e linfócito B (CD20). Dentre os resultados encontrados notou-se uma distribuição das células CD8+ da seguinte forma: 1) difusa na capsula fibrosa dos abscessos crônicos (58,8%) e ausente nos cistos abscedados (64,1%) e cistos inflamatórios (70,6%); 2) zona infiltrativa: difusa nos cistos abscedados (100%) e cistos inflamatórios (82,4%); 3) zona subepitelial: ausente nos cistos inflamatórios (53,0%) e difusa nos cistos abscedados (56,4%); 4) zona de supuração: difusa nos abscessos crônicos (100%) e cistos abscedados (97,5%). As células CD20+ apresentavam a seguinte distribuição: 1) cápsula fibrosa: ausente nos cistos inflamatórios (100%), cistos abscedados (94,8%) e abscessos crônicos (88,3%); 2) zona infiltrativa: difusa nos cistos abscedados (100%) e cistos inflamatórios (53%); 3) zona subepitelial: ausente nos cistos inflamatórios (58,8%) e focal nos cistos abscedados (46,2%); 4) zona de supuração: difusa nos cistos abscedados (100%) e abscessos crônicos (100%). Em conclusão é possível afirmar que a distribuição linfocitária é predominantemente difusa para ambos os tipos de linfócitos.

The objective of this study was to investigate the distribution of CD8+ and CD20+ lymphocytes in chronic periapical inflammatory lesions. A total of 90 periapical inflammatory lesions (chronic abscesses, abscessed cysts, and inflammatory cysts) were evaluated. The biotin-streptavidin immunohistochemical technique was used to identify cytotoxic/suppressor T-lymphocytes (CD8) and B-lymphocytes (CD20). Age ranged from 10 to 67 years. Patients between 26 and 45 years old (54.4%), females (52.2%), and white patients (74.4%) were more frequently affected. CD8+ cell distribution was as follows: 1) fibrous capsule: diffuse in 58.8% of chronic abscesses and absent in 64.1% of abscessed cysts and in 70.6% of inflammatory cysts; 2) infiltration zone: diffuse in 100% of abscessed cysts and in 82.4% of inflammatory cysts; 3) sub-epithelial zone: absent in 53.0% of inflammatory cysts and diffuse in 56.4% of abscessed cysts; 4) suppurative zone: diffuse in 100% of chronic abscesses and in 97.5% of abscessed cysts. CD20+ cell distribution was as follows: 1) fibrous capsule: absent in 100% of inflammatory cysts, in 94.8% of abscessed cysts, and in 88.3% of chronic abscesses; 2) infiltration zone: diffuse in 100% of abscessed cysts and in 53% of inflammatory cysts; 3) sub-epithelial zone: absent in 58.8% of inflammatory cysts and focal in 46.2% of abscessed cysts; 4) suppurative zone: diffuse in 100% of abscessed cysts and in 100% of chronic abscesses. The distribution of the lymphocytic infiltrate in the lesions was usually diffuse for both types of lymphocytes.