Ameloblastic fibro-odontoma: A case report

Ameloblastic fibro-odontoma (AFO) is a rare, benign, slow-growing odontogenic tumor, generally asymptomatic and more prevalent in children and adolescents. We report a case of AFO in the mandible of an eight-year-old Caucasian male patient, and review the literature. Intraoral examination revealed a swelling extending from the deciduous second molar to the retromolar triangle, covered with normal mucosa. A panoramic radiograph showed a large, well-demarcated radiolucency with radiopaque areas. The provisional diagnosis was of AFO, and so an incisional biopsy was performed. Histologically, the lesion was composed of connective tissue resembling the dental papilla, with epithelial strands or islands, as well as denticles and amorphous masses of enamel and dentin consistent with a diagnosis of AFO. Surgical excision and curettage of the lesion were performed. The patient has been monitored for eight years and the lesion has not recurred.

Clinicopathological analysis of oral mucous autoimmune disease: A 27-year study

Objectives: The aim of the present study was to analyze the main clinical and histopathological features of autoimmune diseases with oral manifestations such as oral lichen planus (OLP); mucous membrane pemphigoid (MMP); pemphigus vulgaris (PV) and erythema multiforme (EM). Study design: Retrospective review of 5770 files from the Oral Pathology Laboratory of Sao Jose dos Campos Dental School, São Paulo State University (UNESP) comprising a 27- year period from 1974 to 2000.Results: The cases accounted for 64 (1.10%) of 5770 anatomopathological examinations performed over the study period. Among the autoimmune diseases diagnosed, 49 (76.56%) were OLP, 6 (9.37%) were MMP, 5 (7.82%) were em and 4 (6.25%) were PV. Descriptive statistical analysis was used.Conclusion: The initial manifestations of most autoimmune diseases occur in the oral mucosa. An earlier diagnosis and proper therapeutic protocol will delay the dissemination of the lesions, thus greatly contributing to a better prognosis and quality of life of the patient.

Intraosseous foreign-body granuloma in the mandible subsequent to a 20-year-old work-related accident

The purpose of this article was to describe the clinical and microscopic features of an intraosseous foreign-body granuloma in the mandible that developed after the traumatic implantation of metal fragments during a work-related accident. A 65-year-old male patient had a severe pain in the body of mandible. Clinical examination showed facial asymmetry and a scar, extending to the left mental region. Intraoral examination revealed a soft mass involving the left alveolar bone with normal appearance of the mucosa surface. Panoramic radiographs showed a radiolucent lesion along the mandible extending from the central incisive to the first molar. Computed tomography revealed an osteolytic mass in the same area. His medical history included a work-related accident twenty years prior to evaluation. During the biopsy an important amount of bright metal-like pieces surrounded by soft tissue were found. A microscopic examination showed a foreign body associated with an aggregation of multinucleated giant cells. The final diagnosis was a foreign body granuloma. Even though foreign-body granulomas in the mandible are rare lesions, dentists should be familiar with their features and include them in the differential diagnosis of tissue masses.

Effects of Chamomilla recutita (L.) on oral wound healing in rats

Objectives. The purpose of this study was to evaluate the effect of Chamomilla recutita on the healing of ulcers in rats.Study Design. A 5-mm wound was inflicted on the tongue of 36 rats. Treatment group animals were treated topically with 0.04 mL/day of chamomile ointment, whereas control group animals were not treated. Animals were sacrificed after 3, 7 or 10 days. Semi-quantitative analysis of the degree of inflammation, fibroblast count and wound size was performed, as well as histometric analysis of re-epithelialization and percentage of collagen fibers of the lesion.Results. Animals treated with chamomile showed the best results regarding epithelialization and percentage of collagen fibers after 10 days. As expected, time had a statistically significant effect (p<0.05) on fibroblast count, epithelialization, inflammation and wound size; animals sacrificed at 3 days showed the worst results.Conclusions. Chamomile stimulated re-epithelialization and the formation of collagen fibers after 10 days of treatment; it did not, however, influence inflammation or fibroblast count.

Porous titanium for biomedical applications: An experimental study on rabbits

Objective: The aim of this study was to carry out an in vivo assessment of bone ingrowth in two different types of porous titanium -the first being completely porous, and the second with a porous surface and dense nucleus, manufactured by powder metallurgy- and to evaluate their mechanical properties. Study design: Ten scaffolds from each group were submitted to metallographic analysis and compression tests. Next, two scaffolds of each type were inserted into 14 rabbits, which were sacrificed 8 weeks after surgery. The samples were submitted for histological examination. Results: Metallographic analysis revealed interconnected pores, and the average interconnected pore diameter was about 360 mm, with 36% total porosity. The totally porous titanium samples and the titanium samples with porous surface and dense nucleus showed an average compressive strength of 16.19 MPa and 69.27 MPa, respectively. After 8 weeks, the animals showed bone ingrowth, even into the most internal pores. Conclusions: The pore morphology was effective in permitting bone ingrowth in both groups. Titanium scaffolds with a porous surface and dense nucleus showed the best mechanical properties and most adequate interface.

Comparative analysis of cell proliferation ratio in oral lichen planus, epithelial dysplasia and oral squamous cell carcinoma

Background: Although oral lichen planus has been classified by the World Health Organization (WHO) as a potentially malignant disorder, such classification is still the target of much controversy. Aim: To evaluate the cell proliferation rate in oral lichen planus, comparing it to the rate observed in epithelial dysplasia and oral squamous cell carcinoma, aiming at indications which might indicate the potential for malignant transformation. Material and Methods: Twenty-four cases of each lesion were submitted to the streptoavidin-biotin and AgNOR technique to evaluate the immunohistochemical expression of PCNA and the mean NORs/ nucleus, respectively. Results: Positivity for PCNA was observed in 58.33% of oral lichen planus cases, 83.33% of epithelial dysplasia cases and 91.67% of oral squamous cell carcinoma cases. Chi-squared test showed that the number of positive cases for PCNA was significantly lower in oral lichen planus than in oral squamous cell carcinoma (p<0.05). No significant statistical difference between oral lichen planus and epithelial dysplasia (p>0.05) and between the epithelial dysplasia and oral squamous cell carcinoma (p>0.05) was observed. The mean NORs/ nucleus in oral lichen planus, epithelial dysplasia and oral squamous cell carcinoma were 1.74 +/- 0.32, 2.42 +/- 0.62 e 2.41 +/- 0.61, respectively. Variance analysis (ANOVA) revealed significant statistical difference between oral lichen planus and the other studied lesions (p<0.05). Conclusion: Oral lichen planus cell proliferation rate was less than in oral epithelial dysplasia and oral squamous cell carcinoma which might explain the lower malignant transformation rate.

Rational use of antimicrobials in dentistry during pregnancy

The use of medicines during pregnancy deserves special attention from dentists due to the potential risks to fetal development. The prescription of antimicrobial drugs during this period must be based not only on the etiology of the disease but also on the drug's effect on the embryo, which may be toxic, possibly leading to irreversible lesions. Interest in studies of the teratogenic effects of drugs increased in response to reports of the high incidence of phocomelia in patients treated with thalidomide. Although teratogenicity has long been known, pregnant women today are still exposed to this risk. The effects of drugs depend on the level of susceptibility of the fetus and on the period of exposure during pregnancy. In this context, and considering the paucity of studies on this subject in dentistry, the aim of this review was to offer an up-to-date compilation of data on the antimicrobial drugs most frequently used during pregnancy and the effects of their use.

Effect of low-calcium diet and grind diet on bone turnover of ovariectomized female rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A influência da deficiência estrogênica no processo de remodelação e reparação óssea

INTRODUÇÃO: Nestes últimos anos, descobriu-se a complexidade dos mecanismos que influenciam a atividade óssea, e grande parte das pesquisas direcionou-se para o estudo de fatores capazes de modular as funções ósseas. Essa expansão da pesquisa deve-se, em parte, ao reconhecimento da osteoporose como importante problema na velhice. A osteoporose constitui uma das osteopatias mais comuns, caracterizando-se pela redução da massa óssea, determinada, por sua vez, pelo desequilíbrio entre reabsorção e neoformação. OBJETIVO: Apresentar uma revisão da literatura sobre os principais aspectos da remodelação e da reparação associados à deficiência estrogênica. Remodelação óssea: O osso apresenta processo contínuo de remodelação, entretanto anormalidades nesse processo ocorrem em algumas doenças, entre elas a osteoporose, sendo que a deficiência estrogênica parece ter o papel principal na sua gênese. Reparação óssea: Tal processo envolve uma cascata complexa de respostas biológicase, assim como a remodelação, é afetado por fatores locais e externos e regulado pela interação de diferentes mecanismos. Portanto, o aumento ou o decréscimo da capacidade de reparação óssea têm sido relacionados a alterações ocorridas na remodelação. Deficiência estrogênica e metabolismo ósseo: A maioria dos autores sugere uma redução na capacidade de remodelação e de reparação do tecido. DISCUSSÃO: Ainda não está determinado qual estágio da reparação é mais alterado, se a fase inicial de formação do calo ósseo, se a de mineralização ou se a fase tardia da reparação, a remodelação óssea. CONCLUSÃO: Como os mecanismos fisiológicos e a patogênese das alterações ósseas causadas pela deficiência estrogênica não estão completamente estabelecidos, novas pesquisas ainda são necessárias.

Leiomioma vascular bucal: relato de dois casos, revisão da literatura e estudo imuno-histoquímico

INTRODUÇÃO: Os leiomiomas são neoplasias benignas do músculo liso que ocorrem mais comumente nos tratos geniturinário e gastrintestinal, entretanto são raros na cavidade bucal, na qual provavelmente a maioria desses tumores tem sua origem a partir de músculo liso vascular. OBJETIVOS: Relatar dois casos com história clínica semelhante, confrontando seus aspectos com aqueles encontrados na literatura. RELATO DOS CASOS: Dois casos de mulheres na quinta e sexta décadas de vida apresentando nódulo submucoso em ventre lingual. Após exame microscópico que revelou numerosos vasos sangüíneos entremeados a células fusiformes, com núcleos ovalados ou alongados, e exame imuno-histoquímico com positividade para actina de músculo liso nos dois casos, o diagnóstico final foi leiomioma vascular. CONCLUSÃO: O estudo do leiomioma vascular bucal é de extrema importância devido à raridade e semelhança desse com outras lesões da cavidade bucal. A análise imuno-histoquímica é importante para o diagnóstico final do leiomioma.

Biocompatibility of a chlorhexidine local delivery system in a subcutaneous mouse model

Objective: This study aimed evaluating histologically and histomorphometrically the response of the conjunctive tissue face to the implant of chlorhexidine chips in the subcutaneous tissues of rats. Study Design: In this research 35 male rats Wistar were used to analyze the biocompatibility and the degradation process of chlorhexidine chip. In each animal, it was made 2 incisions for subcutaneous implantation of chlorhexidine chip (test group) and a polytetrafluorethylene membrane (control group). The morphological changes in subcutaneous implantations were assessed after 1, 3, 5, 7, 10, 14, 21 days. The data were submitted to Friedman nonparametric test to analyze the comparisons among observation periods and to allow the comparison among groups. Results: Differences were found in the analysis of the inflammatory response when comparing the tested materials (p values <= 0.05). In test group was observed hemorrhage, edema and intense inflammatory infiltrate predominantly neutrophilic around material. From 3-day and subsequent periods was verified granulation tissue externally at this infiltrate. From 10-day on was observed crescent area of degradation of chlorhexidine chip, associated with neutrophilic and macrophagic infiltrate, that maintained until 21-day. In the control group, moderate inflammatory infiltrate was observed initially, predominantly polymorphonuclear, edema and granulation tissue 3-day period. The inflammatory infiltrate was gradually replaced for granulation tissue, culminating in a fibrous capsule. Giant multinucleate cells situated at contact interface with the coating was examined since 3-day and persisted until 21-day. Conclusion: The chlorhexidine chip induces an intense acute inflammatory response at subcutaneous tissue of rats. Therefore, at conditions of this study was not biocompatible.

Calcium sulfate and PTFE nonporous barrier for regeneration of experimental bone defects

The aim of the study was to evaluate the possibility to obtain guided bone regeneration with two types of physical barriers (calcium sulfate and PTFE nonporous barrier) in surgical defects created in rat parietal bones. In the right parietal bone the calcium sulfate barrier filled out the whole defect and in the left parietal bone the barrier of PTFE was positioned in the floor and externally to the surgical defect. After 7, 14, 30 and 45 days four animals were sacrificed in each period and the bone containing the defects were submitted to the microscopic analysis. The results of the study revealed that the PTFE barrier was more effective for bone regeneration in shallow transcortical defects compared to the calcium sulfate. However, additional experiments are necessary to determine if calcium sulfate would be successful in other bone defects types or the use of the material under another consistence could complement the results obtained in this work.

Dental fluorosis: Exposure, prevention and management

Dental fluorosis is a developmental disturbance of dental enamel, caused by successive exposures to high concentrations of fluoride during tooth development, leading to enamel with lower mineral content and increased porosity. The severity of dental fluorosis depends on when and for how long the overexposure to fluoride occurs, the individual response, weight, degree of physical activity, nutritional factors and bone growth. The risk period for esthetic changes in permanent teeth is between 20 and 30 months of age. The recommended level for daily fluoride intake is 0.05 - 0.07 mg F/Kg/day, which is considered of great help in preventing dental caries, acting in remineralization. A daily intake above this safe level leads to an increased risk of dental fluorosis. Currently recommended procedures for diagnosis of fluorosis should discriminate between symmetrical and asymmetrical and/or discrete patterns of opaque defects. Fluorosis can be prevented by having an adequate knowledge of the fluoride sources, knowing how to manage this issue and therefore, avoid overexposure.

Terapia celular em doenças pulmonares: existem perspectivas?

A terapia celular poderia ser conceituada de forma ampla e genérica como o emprego de células para tratamento de doenças. Apesar de um número não tão expressivo de relatos tendo o pulmão como objeto de estudo na terapia celular em pacientes humanos, há dados consistentes da literatura, tanto em humanos, quanto em modelos animais,que evidenciam a migração de células-tronco da medula óssea para o pulmão,em diferentes situações experimentais. Esses resultados forneceram o embasamento experimental para o emprego de células-tronco na regeneração do tecido pulmonar em modelos animais. em nosso laboratório, vários projetos de pesquisa têm sido conduzidos com a finalidade de avaliar a resposta pulmonar (morfológica e funcional) ao tratamento com células-tronco adultas em camundongos com doença pulmonar obstrutiva crônica (DPOC) induzida experimentalmente. Os resultados obtidos, aliados àqueles de outros grupos de pesquisa, permitem aventar a possibilidade de aplicação, a curto prazo, da terapia celular em pacientes com DPOC. em outra patologia pulmonar, fibrose cística (FC), cuja abordagem terapêutica com células-tronco apresenta aspectos particulares em relação às patologias pulmonares crônico-degenerativas, há avanços promissores e potencialmente interessantes; no entanto, os resultados podem ser considerados incipientes e deve-se assinalar, portanto, que a associação da terapia gênica e celular apresenta-se como uma alternativa possível, mas ainda muito distante quanto à sua consolidação e incorporação como opção terapêutica segura e eficaz em FC. Por outro lado, tendo por embasamento os resultados obtidos em modelos experimentais, é possível postular que a terapia celular com células-tronco hematopoéticas (ou de outras fontes) encerra perspectivas consistentes de aplicação em diversas outras patologias pulmonares humanas, especialmente em DPOC.

Validade da citologia cervicovaginal na detecção de lesões pré-neoplásicas e neoplásicas de colo de útero

Introdução: O exame colpocitológico ou teste de Papanicolaou permite o diagnóstico precoce do câncer de colo do útero. O êxito no rastreamento desta doença dependerá, além de outros fatores, da acuidade diagnóstica do exame colpocitológico. Objetivos: Avaliar a acurácia diagnóstica da citologia cervicovaginal na detecção de lesões cervicais através da comparação citoistopatológica. Material e métodos: Avaliou-se o grau de concordância entre os exames citológico e histopatológico de 373 pacientes atendidas em um hospital universitário no período de 1990 a 1997 e foram calculados os indicadores: sensibilidade, especificidade, valores preditivos positivos e negativos e as taxas de falsos positivos e falsos negativos do exame. Resultados: A taxa bruta de concordância citoistopatológica foi de 65,1%. A sensibilidade do exame foi alta (96,0%), no entanto sua especificidade foi baixa (51,5%), significando a inclusão de muitos resultados falsos positivos. A taxa de falsos positivos foi de 48,4%, enquanto a de falsos negativos foi de 4%. Discussão: Apesar de a sensibilidade do teste ser alta, sua especificidade é baixa, significando que muitas mulheres seriam falsamente diagnosticadas como doentes, levando a um número elevado de resultados falsos positivos e custos desnecessários, além do potencial caráter iatrogênico que esta ação poderia assumir. No entanto, um exame altamente sensível é o teste de escolha para programas de rastreamento de câncer cervical na população feminina. Conclusões: Para garantir a acuidade diagnóstica do teste de Papanicolaou são essenciais atividades de controle de qualidade nos laboratórios, tanto do procedimento colpocitológico quanto do histopatológico, permitindo, assim, o êxito na detecção precoce e no tratamento das lesões cervicais.