Prognostic value of the expression and localization of cell proliferation and apoptosis markers in unicystic ameloblastomas.

The aim of this study was to verify whether the expression of cell proliferation and apoptosis markers in different types of unicystic ameloblastoma (UA) is associated with the location of neoplastic cells. Immunohistochemical study with a sample of 32 cases of UA, 11 cases of conventional ameloblastoma (CAM) and ten dental follicles (DF) cases was performed. Cell proliferation was assessed using Ki-67 status, and apoptosis by caspase-3 expression. Mural UA (MUA) showed a higher immunostaining of Ki-67 (p < 0.05) and a lower immunostaining of Caspase-3 (p < 0.05) compared with luminal and intraluminal subtypes of UA and CAM. The neoplastic cells of the MUA's cystic capsule showed a higher expression of Ki-67 protein (p < 0.0001) and a lower expression of Caspase-3 (p < 0.0001) compared with the lumen. DF showed lower Ki-67 and Caspase-3 immunostaining (p < 0.05) than neoplasms. The higher immunoexpression of Ki-67 and the lower immunoexpression of Caspase-3 in MUA, in the parenchyma cells within the cystic capsule, suggest an association between the biological behaviour and location of neoplastic cells in a tumour.

Clinicopathological Features of Metastasis to the Oral and Maxillofacial Region-Multicenter Study.

BACKGROUND: This study aimed to investigate the clinicopathological features of metastases in the oral and maxillofacial regions. METHODS: In this retrospective study, biopsy records were obtained from referral centers for oral and maxillofacial diagnosis in Brazil, Guatemala, Mexico, and South Africa. RESULTS: A total of 120 cases were evaluated. Of these, 53.78% affected female patients, with a mean age of 57.64 years. Intraosseous lesions were more frequent, particularly in the posterior region of the mandible (49.58%). Clinically, most cases presented with symptomatic swelling, with an average evolution time of 25 months. The clinical diagnostic hypothesis in most instances was that of a malignant lesion. Breast cancer was the most common primary tumor location in females, while lung origin was most common in males. In most cases, the primary cancer was an adenocarcinoma (44.73%). The follow-up period was available for 29 cases, and out of these, 20 had died due to the disease. CONCLUSION: Although this is a rare condition, clinicians should be aware that any oral lesions have the possibility of being metastatic, particularly in individuals with a previous history of cancer. The findings from this study could assist clinicians in prompt diagnosing these lesions and subsequent conducting oncologic assessments and treatment.

Does smoking habit affect dendritic cell expression in oral squamous cell carcinoma?

The aim of this study was to determine the presence of immature CD1a+ and mature CD83+ dendritic cells in oral squamous cell carcinoma, to compare immunoreactivity between smokers and nonsmokers, and to correlate the results with histopathological grading. In this observational study, twenty-eight paraffin-embedded biopsies of oral squamous cell carcinoma were retrospectively retrieved and submitted to immunohistochemistry for immature CD1a+ and mature CD83+. Descriptive and statistical analyses were performed. The sample consisted of 18 man (64.3%) and 10 women (35.7%), with a mean age of 64.6 years in the nonsmoker group and 53.2 years in the smoker group. The tongue (11 cases, 39.2%) was the most commonly affected anatomical site, followed by gingiva (6 cases, 21.4%). Histopathological grading revealed 7 low-grade and 7 high-grade malignancy cases in each group, and no correlation with the number of positive DCs. The number of immature CD1a+ was not significantly different between smoker and nonsmoker groups, while a lower number of mature CD83+ was detected in the smoker group (p = 0.001). Smoking changes the oral immune system and decreases the ability to activate and mature dendritic cells, which may influence the development and progression of oral squamous cell carcinoma.

Impact of the COVID-19 pandemic on public University laboratories of oral and maxillofacial pathology: A Brazilian multicenter study.

OBJECTIVE: To evaluate the impact of the COVID-19 pandemic on the number of diagnoses of oral and maxillofacial lesions in public laboratories after one year of COVID-19 outbreak in Brazil. MATERIAL AND METHODS: This is a cross-sectional study. Biopsies submitted to histopathologic examination from March 2019 to February 2020 (pre-pandemic period) and from April 2020 to March 2021 (pandemic period) in nine Brazilian public oral pathology laboratories were retrieved and the number of diagnoses, types of lesion, and percentage changes during both periods were analyzed. RESULTS: There were 7389 diagnoses in the pre-pandemic period and 2728 in the pandemic era, indicating a reduction of 63.08%. The reduction was 64.23% for benign lesions and 49.48% for malignant lesions, with a 50.64% reduction in squamous cell carcinoma. The largest decreases were observed in April 2020 and January 2021. CONCLUSION: An important reduction in the diagnoses of benign and malignant lesions was noted in the Brazilian public oral pathology laboratories during the first year of the COVID-19 pandemic.

Does smoking habit affect dendritic cell expression in oral squamous cell carcinoma?

Abstract: The aim of this study was to determine the presence of immature CD1a+ and mature CD83+ dendritic cells in oral squamous cell carcinoma, to compare immunoreactivity between smokers and nonsmokers, and to correlate the results with histopathological grading. In this observational study, twenty-eight paraffin-embedded biopsies of oral squamous cell carcinoma were retrospectively retrieved and submitted to immunohistochemistry for immature CD1a+ and mature CD83+. Descriptive and statistical analyses were performed. The sample consisted of 18 man (64.3%) and 10 women (35.7%), with a mean age of 64.6 years in the nonsmoker group and 53.2 years in the smoker group. The tongue (11 cases, 39.2%) was the most commonly affected anatomical site, followed by gingiva (6 cases, 21.4%). Histopathological grading revealed 7 low-grade and 7 high-grade malignancy cases in each group, and no correlation with the number of positive DCs. The number of immature CD1a+ was not significantly different between smoker and nonsmoker groups, while a lower number of mature CD83+ was detected in the smoker group (p = 0.001). Smoking changes the oral immune system and decreases the ability to activate and mature dendritic cells, which may influence the development and progression of oral squamous cell carcinoma.

Oral and oropharyngeal lymphomas: A multi-institutional collaborative study.

BACKGROUND: Lymphomas in the oral and oropharyngeal regions are relatively uncommon, and their diagnosis is challenging and complex due to the myriad histopathological subtypes. Herein, we report a large series of oral and oropharyngeal lymphomas and compare our data with the currently available literature. METHODS: All cases diagnosed as lymphomas affecting the oral and oropharyngeal regions were retrospectively retrieved from seven Brazilian institutions. Clinicodemographic data and histopathological features were evaluated and described, while a comprehensive literature review was undertaken in order to compare our findings. RESULTS: A total of 304 cases of oral and oropharyngeal lymphomas were obtained, mostly affecting individuals aged 60-69 years (n = 68) with a mean age at diagnosis of 54.2 ± 20.1 years. Males and females were equally affected. Mature B-cell neoplasms (87.2%) were the most common group, followed by mature T- and NK-cell neoplasms (11.2%) and precursor lymphoid neoplasms (1.6%). The most frequent subtypes in each group were diffuse large B-cell lymphomas, not otherwise specified (n = 99), extranodal NK/T-cell lymphomas, nasal type (n = 12), and B-lymphoblastic leukaemia/lymphomas, not otherwise specified (n = 4). The most commonly involved sites were the palate (26.3%), mandible (13%), and maxilla (10.5%). CONCLUSION: Diffuse large B-cell lymphoma, not otherwise specified, remains the most common subtype of lymphomas in the oral and oropharyngeal region. Older patients are the most affected, with no gender predilection and the palate and jaw are usually affected.

High-fat diet effect on periapical lesions and hepatic enzymatic antioxidant in rats.

AIMS: To evaluate the effects of a high-fat diet (HFD) on the progression of apical periodontitis (AP), local inflammation, systemic antioxidant status, and blood lipid profile in rats. MAIN METHODS: Sixteen male Wistar rats were fed a standard diet (SD) or a HFD. At the sixth experimental week, the pulp chambers of the mandibular first molars were exposed to develop AP. A glucose tolerance test was performed the week before euthanasia. At the tenth experimental week, the animals were euthanized and the livers were collected to estimate catalase (CAT) and reduced glutathione (GSH) levels. Blood was acquired for biochemical analysis. The size of AP was estimated from radiographs and described as AP size-to-body weight ratio; inflammatory grade of AP was determined by histological analysis. KEY FINDINGS: At the end of the experimental period, the rats fed the HFD had 30% less weight (P < 0.0001) and higher blood glucose levels after 30 min of sucrose intake (P < 0.05) than those fed the SD. Animals from the HFD group had lower levels of CAT (P < 0.01), but the same was not observed in the GSH levels. Plasma insulin and total cholesterol were not affected by the diet. The rats fed the HFD presented greater AP than those fed the SD (P < 0.05). However, the local inflammatory infiltrate was similar in both groups. SIGNIFICANCE: The alterations promoted by the consumption of a HFD were not only observed systemically, but also locally, producing greater AP in rats than a SD.

Cytotoxicity of contemporary resin-based dental materials in contact with dentin.

In this study, the cytotoxicity of different combinations of contemporary resin-based restoratives (adhesives, composites, luting agents) against human keratinocytes (HaCaT) was evaluated under two conditions, whether materials were applied to dentin or not. Adhesives (3-step etch-and-rinse/3ER: OptiBond FL; 2-step self-etch/2SE Clearfil SE Bond; Single Bond Universal/UNI), composites (conventional composite resin/CCR: Filtek Z350XT; flowable/FCR: Filtek Z350XT Flow; self-adhesive composite resin/SACR: Dyad Flow), and luting agents (conventional luting agent/CLA: Variolink-II; self-adhesive luting agent/SLA: RelyXU200) were combined according to their clinical use. Eluates from polymerized specimens applied to dentin were placed in contact with cells grown for 1 and 7 d. The controls were defined by cells without material contact. Cell viability was determined using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)] assay. C=C conversion was investigated using Fourier-transform infrared spectroscopy. After 1 d of incubation, when dentin was not present, 2SE yielded the highest cell viability, whereas 3ER, UNI, and SACR showed higher cell viability in the presence of dentin. After 7 d, when dentin was absent, 2SE and CLA achieved significantly higher cell viability. The presence of dentin resulted in a drastically higher cell viability for all materials, except 2SE and CLA. UNI had the lowest C=C conversion. The presence of dentin was a significant factor, which resulted in higher cell viability than what was seen for the material specimens per se. All materials resulted in a lower viability of HaCaT than what was seen under the no-material control conditions, with effects mainly limited to the first 24 h.

Nitrogen-containing bisphosphonate therapy-Part II: Assessment of alveolar bone tissue inflammatory response in rats-A blind randomized controlled trial.

This study aimed to evaluate the alveolar bone tissue inflammatory response in rats undergoing zoledronic acid therapy. The study sample was composed of 28 Wistar rats. Animals from the test group GTa received a weekly intraperitoneal dose of 0.2 mg/kg of zoledronic acid for 3 weeks, while test group GTb received the same dose for 8 weeks. A physiological saline dose, equivalent to that of the medication, was administered to the controls in groups GCa and GCb. A defect was created in the dental crown of the lower first molars using a drill to simulate pulp and periapical injury. Data were evaluated regarding image grey levels by cone-beam computed tomography and histologically by assigning scores for the presence of inflammatory infiltrate, type of infiltrate, vascularization, bone necrosis and dental resorption. Grey levels in the 3-week therapy group (GTa) showed more pronounced changes in comparison with those seen in the GCa group (P < 0.05). Evaluation of the scores demonstrated no association between any of the variables amongst the groups (>0.05). However, bone remodelling decreased in the groups receiving the medication. Bone necrosis was present more frequently in group GTb than in the control group GCb. The results suggest that the drug interfered in the reaction capacity of the alveolar bone tissue as test group GTa showed higher grey levels in comparison to the control group GCa. In addition, there was less bone remodelling activity, with the appearance of bone necrosis zones and intense acute inflammatory infiltrate associated with the 8-week therapy group GTb.

A single-center 18-year experience with oral candidiasis in Brazil: a retrospective study of 1,534 cases.

Despite the large number of published studies about oral candidiasis and associated risk factors, reports of large single-center retrospective studies on the prevalence of oral candidiasis, risk factors, and the oral candidiasis types diagnosed more frequently in oral diagnostic reference centers are scarce. The objective of the present study was to retrospectively survey the demographic and clinical profiles of 1,534 patients diagnosed with candidiasis and treated at the Center for Diagnosis of Oral Diseases (CDOD), Pelotas Dental School, Federal University of Pelotas between 1997 and 2014. Using a retrospective, cross-sectional, epidemiological design, data on race, gender, age, systemic diseases, oral candidiasis type and location, symptoms, and harmful habits such as smoking and alcohol consumption were collected. The statistical analysis was performed using STATA version 13.1. Risk factors for chronic atrophic candidiasis (CAC) were evaluated using Poisson regression with robust variance (p ≤ 0.05). The majority of patients with oral candidiasis seen at the CDOD over the 18-year period of analysis were Caucasian women, aged 51-60 years, nonsmokers, and nondrinkers, with no systemic disease, and who wore some form of dental prostheses. CAC was the single most common clinical type of candidiasis detected, and the most frequently affected oral site was the palate. These data from a large single-center in Brazil agree with previous evidence about the clinical and demographic profiles of patients with oral candidiasis.

Clinicopathologic and immunohistochemical characterization of 14 cases of angioleiomyomas in oral cavity

BACKGROUND: Angioleiomyoma (ALM) is a benign neoplasm that originates from vascular smooth muscle. It is extremely rare in oral cavity. The objective of this study was to evaluate the clinicopathological and immunohistochemical characteristics of all oral angioleiomyomas registered in a Center of Diagnosis of Oral Diseases from 1959 to 2017. MATERIAL AND METHODS: Slides from 14 cases of ALM stained with hematoxylin and eosin (H&E) were analyzed to confirm the diagnosis. Moreover, an immunohistochemical panel with alpha-smooth muscle actin (alpha-SMA), desmin, AE1/AE3, CD68, S-100, and CD34 antibodies was performed to evaluate semi-quantitatively the positive cells. RESULTS: ALM correspond to 0.08% of all benign oral tumors analyzed during the 57-year period. The mean age of the patients was 45 years with a predilection to males (58%). The most frequently reported site was lips (50%). Microscopic analysis on H&E sections revealed similar pattern in all cases, showing well-circumscribed and encapsulated tumors, characterized by a proliferation of smooth muscle cells and wide vascular spaces of varying sizes. The predominant immuno profiles were: alpha-smooth muscle actin (alpha-SMA) positive (strong immunoreactivity); positive variable pattern for desmin, negative immunoprofile for AE1/AE3, CD68, and S-100. The endothelial cells of vascular spaces were CD34+. CONCLUSIONS: Based on the results, the alpha-SM actin can be elected as a good marker for angioleiomyomas and can help the confirmation of the morphologic diagnosis of this lesion

Retrospective Study of 383 Cases of Fibro-Osseous Lesions of the Jaws.

PURPOSE: The aims of this study were to describe the clinical and radiologic features of 383 fibro-osseous lesions (FOLs) from an oral pathology reference service in Brazil and to compare the findings with previous studies. The hypothesis of the study was that the most common type of FOL would differ from other investigations. MATERIALS AND METHODS: We conducted a descriptive and retrospective study with review of the records of the clinical and biopsy services (1990 to 2015). All records of the patients included showed a definitive diagnosis of FOL. The primary outcome variable was the type of FOL, and the predictor variables were gender, age, ethnicity, location, and clinical and radiologic characteristics. Descriptive analyses and χ2 tests were performed. The P value was set at .05. RESULTS: From the 27,998 records available, 383 showed FOLs, with 187 (48.8%) being cemento-osseous dysplasias (CODs), 103 (26.9%) being fibrous dysplasias (FDs), and 93 (24.3%) being ossifying fibromas (OFs). The mean age of the patients was 38.5 ± 17.5 years. CODs presented a predilection for female gender (n = 314, 82.0%), African descent (n = 134, 71.6%), and the mandible (n = 248, 64.6%). The most common radiologic feature was a mixed radiolucent-radiopaque image (n = 149, 51.7%). FDs and OFs were commonly diagnosed during the first and second decades of life (P < .001), whereas CODs were more frequently diagnosed beyond the third decade (P < .001). Secondary osteomyelitis was more significantly observed in CODs (P < .001) than in FDs and OFs. Swelling was more frequently reported for FDs and OFs than for CODs (P < .001). CONCLUSIONS: CODs were the most frequently observed FOLs in this Brazilian population. Female patients, patients of African descent, and patients with mandibular localization were most commonly affected by these conditions. The most common type of FOL differed from that in similar case reports or series from various geographic locations. It is believed that the data source (clinical and/or biopsy services) can directly influence the outcome.

Development of a dual-cure mineral trioxide aggregate-based cement: Biological, physical, and mechanical properties.

PURPOSE: The purpose of this study is to compare the physical, mechanical, and biocompatibility properties of a new dual-cure white mineral trioxide aggregate (D-W-MTA) and a commercial W-MTA. MATERIALS AND METHODS: Diametral tensile strength (DTS), water sorption (WSp), and water solubility (WSl) tests were performed. Cytotoxicity was observed in primary culture of human pulp fibroblasts (HPFs) and mouse 3T3/NIH fibroblast lineage. Specimens of both materials were embedded in 1 mL of Dulbecco's modified essential medium for 24 h. Cells were incubated for 24 h with the eluates. Cytotoxicity was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and genotoxicity by micronucleus (MN) formation. Data were analyzed by ANOVA and Kruskal-Wallis tests considering P < 0.05. RESULTS: D-MTA and W-MTA not showed cytotoxic effect on the two cell lines. However, D-MTA stimulated HPF growth. The MN count was similar to that of the control group for D-MTA and W-MTA. D-MTA presented lower DTS and WSl. Nevertheless, WSp was similar in the two groups. CONCLUSION: The results suggest that D-MTA is a promising material for pulp capping. Thus, in vivo tests should be performed to evaluate the performance of this material.

Retrospective analysis of jaw biopsies in young adults. A study of 1599 cases in Southern Brazil

Background: To evaluate the prevalence and the characteristics of jaw lesions diagnosed in young adults aged 20 to 30 years in a southern Brazil reference center, over a period of 25 years. And to analyze the concordance between clinical and histological diagnosis. Material and Methods: In this cross-sectional retrospective study, the biopsies files from this center were retrieved and data regarding sex, age, bone localization, clinical and histological diagnosis were collected. The histological diagnosis were grouped into the categories Cystic lesions of odontogenic origin, Periapical inflammation, Odontogenic tumors, Bone diseases, Health tissue and Nonspecific diagnostic. Absolute and relative frequencies were estimated with descriptive analysis. The agreement between clinical and histological diagnosis was measured through Kappa statistic. Results: A total of 18,181 histopathological analysis were performed during the period of the study, registering 1,599 jaw lesions in young adults. The average age of individuals was 24,59 years (SD 3,1). Nine hundred ninety-one (62%) lesions were found in females and 608 (38%) in males. More than half of pathologies were cystic lesions of odontogenic origin (822/51.4%), followed by periapical inflammation (282/17.6%). Regarding the site of lesions, more than half occurred in posterior mandible (877/54.8%), followed by posterior maxilla (339/21.2%). The most frequent entities were periapical cyst, chronic periapical granuloma, dental follicle and paradental cyst, corresponding to a total of 1,202 (75.2%) evaluated cases. In relation to the analysis of concordance between clinical and histological diagnosis the general Kappa index was 0.5, which is considered moderate. Finally, the findings confirm data from literature about the most frequent jaw pathologies in young adults and serve as aid for preventive measures of some entities. Additionally, they can improve the formulation of differential diagnosis and the patient management (AU)

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Demographic and Clinical Profile of Oral Squamous Cell Carcinoma from a Service-Based Population

Abstract The aim of this study was to evaluate the demographic and clinical profile of the oral squamous cells carcinoma (OSCC) cases registered in a center of oral diagnosis in southern Brazil. Eight hundred and six individuals with OSCC from 1959 to 2012 were included in this study. The variables recorded were: sex, age, occupation according to workplace, alcohol and tobacco consumption, skin color, tumor location, histological type, clinical appearance, size, evolution time, presence of pain and lymph node metastasis. Descriptive analysis was performed and the associations between variables were assessed using the chi-square and Fisher's exact test, with a confidence level of 5%. OSSC was more common in males (76.6%) aged between 51 to 70 years (53.9%). The most frequent sites were lower lip vermilion (23.3%), tongue (20.2%) and gingiva/alveolar ridge (18.1%). There was a strong association between outdoor occupation and white skin color with lip squamous cell carcinoma (LSCC). OSCC intraoral lesions were commonly more painful, larger than 2 cm and presented lymphatic metastasis. In conclusion, most of the results confirm the data from literature about sex, age, tumor location and occupation. Moreover, the positive correlations between LSCC and occupation, between LSCC and white skin color, and between bigger lesions and presence of pain/cervical metastasis also corroborate the literature data.

Resumo O objetivo desse estudo foi avaliar o perfil clínico-demográfico dos casos de carcinoma de células escamosas oral (CCEO) oral registrados em um centro de diagnóstico bucal no Sul do Brasil. Oitocentos e seis indivíduos com CCEO de 1959 a 2012 foram incluídos no estudo. As variáveis coletadas foram: sexo, idade, ocupação de acordo com o ambiente de trabalho, consumo de álcool e tabaco, cor de pele, localização do tumor, tipo histológico, aparência clínica, tamanho, tempo de evolução, presença de dor e metástase linfonodal. Foi realizada análise descritiva e as associações entre as variáveis foram avaliadas usando qui-quadrado e teste exato de Fisher, com nível de confiança de 5%. CCE oral foi mais comum em homens (76,6%), entre 51 e 70 anos de idade (53,9%). Os sítios mais frequentes foram vermelhão de lábio inferior (23,3%), língua (20,2%) e gengiva/rebordo alveolar (18,1%). Houve uma forte associação entre ocupação em ambiente externo e cor de pele branca com CCEO em lábio. Lesões intraorais de CCEO foram comumente mais dolorosas, maiores que 2 cm e apresentaram metástase linfática. Em conclusão, a maioria dos resultados confirma os dados da literatura em relação a sexo, idade, localização do tumor e ocupação. Além disso, as correlações positivas entre CCE em lábio e ocupação, entre CCEO em lábio e cor de pele branca, e entre lesões maiores e presença de dor/metástase cervical também corroboram os dados da literatura.

Demographic and Clinical Profile of Oral Squamous Cell Carcinoma from a Service-Based Population.

The aim of this study was to evaluate the demographic and clinical profile of the oral squamous cells carcinoma (OSCC) cases registered in a center of oral diagnosis in southern Brazil. Eight hundred and six individuals with OSCC from 1959 to 2012 were included in this study. The variables recorded were: sex, age, occupation according to workplace, alcohol and tobacco consumption, skin color, tumor location, histological type, clinical appearance, size, evolution time, presence of pain and lymph node metastasis. Descriptive analysis was performed and the associations between variables were assessed using the chi-square and Fisher's exact test, with a confidence level of 5%. OSSC was more common in males (76.6%) aged between 51 to 70 years (53.9%). The most frequent sites were lower lip vermilion (23.3%), tongue (20.2%) and gingiva/alveolar ridge (18.1%). There was a strong association between outdoor occupation and white skin color with lip squamous cell carcinoma (LSCC). OSCC intraoral lesions were commonly more painful, larger than 2 cm and presented lymphatic metastasis. In conclusion, most of the results confirm the data from literature about sex, age, tumor location and occupation. Moreover, the positive correlations between LSCC and occupation, between LSCC and white skin color, and between bigger lesions and presence of pain/cervical metastasis also corroborate the literature data.

Osteoma periférico mandibular: relato de caso / Mandibular peripheral osteoma: case report

Osteomas são tumores benignos compostos de osso maduro compacto ou esponjoso, podendo apresentar-se clinicamente na periferia, intraósseo, ou no interior dos tecidos moles. São essencialmente restritos ao esqueleto craniofacial, ocorrendo com maior frequência na mandíbula, sendo raramente diagnosticados em outros ossos. A variável osteoma periférico apresenta-se como uma massa óssea pediculada, de crescimento lento, assintomática, isolada e unilateral. Sua frequência é maior em homens, entre a segunda e quinta décadas de vida, sendo sua etiopatogenia amplamente discutida, podendo ser de origem reacional, traumatológica, inflamatória, ou alteração na fisiologia óssea. Comumente esta lesão está associada a pacientes portadores da Síndrome de Gardner. Objetiva-se, através de relato de caso clínico, discutir a causa, aspectos clínicos, radiográficos e histológicos desta neoplasia, assim como seu tratamento.

Osteomas are benign tumors composed of compact or cancellous mature bone, which may present clinically in the periphery, intra-bone or inside soft tissues. They are essentially restricted to craniofacial skeleton, occurring more frequently in the jaw, rarely diagnosed in other bones. The variable peripheral osteoma usually presents as a pedicled bone mass, of slow growth, asymptomatic, isolated, and unilateral. It is more frequently found in men, between the second and fifth decades of life, being its etiopathogenesis widely discussed, its origin may be reactive, inflammatory, from trauma or physiological bone changes. These lesions are commonly associated with patients with GardnerÆs Syndrome. Through a case report this study aims to discuss cause, clinical, radiographic and histological aspects of this neoplasm, as well as its treatment.

Microscopic Evaluation of the Effect of Oral Microbiota on the Development of Bisphosphonate-Related Osteonecrosis of the Jaws in Rats.

OBJECTIVES: Osteonecrosis of the jaws is a side effect associated with the use of bisphosphonates. Using histologic analysis, this study aimed to evaluate the influence of microbial colonies in the development of osteonecrosis in the jaws of rats subjected to nitrogenous and non-nitrogenous bisphosphonates, undergoing surgical procedures. MATERIAL AND METHODS: Thirty-four rats (Rattus norvegicus, Wistar strain) were allocated randomly into three groups: 12 animals treated with zoledronic acid; 12 animals treated with clodronate; and 10 animals treated with saline. Sixty days after the start of treatment, the animals underwent three extractions of the upper right molars. After 120 days of drug administration, the rats were killed. Histologic analysis was performed on specimens stained with hematoxylin and eosin by the technique of manual counting points using Image-Pro Plus software on images of the right hemimaxilla. RESULTS: Osteonecrosis was induced in the test groups. There was no statistically significant association between the presence of microbial colonies and the presence of non-vital bone (Kruskal-Wallis, P > 0.05). CONCLUSIONS: Use of zoledronic acid was associated with non-vital bone and the results suggested that the presence of microbial colonies does not lead to osteonecrosis.