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1.
Med Oral Patol Oral Cir Bucal ; 27(4): e310-e318, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35660729

RESUMO

BACKGROUND: Actinic cheilitis is a potentially malignant lesion most commonly found in the lower lip of individuals with chronic exposure to ultraviolet radiation. The aim of this study was to develop and to test a clinical index that can be used to assess the severity of actinic cheilitis. MATERIAL AND METHODS: The clinical index of actinic cheilitis was applied to 36 patients. An incisional biopsy was obtained to grade oral epithelial dysplasias following the World Health Organization (WHO) and binary systems, and to evaluate their association with clinical characteristics by Fisher's exact test (P<0.05). The accuracy of the index was evaluated based on sensitivity, specificity, positive and negative predictive values, and receiver operating curve. RESULTS: The blurring between the border of the lip and the skin was significantly associated with cases without dysplasia/mild epithelial dysplasia (P=0.041) and with low risk of malignancy (P=0.005). Ulcers and crusts were significantly associated with moderate/severe epithelial dysplasia (P=0.002 and P=0.012, respectively) and high risk of malignancy (P=0.005 and P=0.045, respectively). Erosion showed a significant association only with high-risk cases of malignancy (P=0.024). The cut-off values of the diagnostic test showing the best performance were 10 for the WHO grading system and 11 for the binary system. CONCLUSIONS: The index cut-offs with the highest accuracy were considered indicators for a biopsy. Erosion, ulceration and crusts were associated with more severe oral epithelial dysplasias.


Assuntos
Queilite , Neoplasias Labiais , Queilite/diagnóstico , Queilite/etiologia , Queilite/patologia , Humanos , Hiperplasia/patologia , Lábio/patologia , Neoplasias Labiais/diagnóstico , Raios Ultravioleta
2.
Med Oral Patol Oral Cir Bucal ; 25(3): e370-e374, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32040463

RESUMO

BACKGROUND: The objective of this study was to describe the upper and lower lip lesion occurrence in an oral diagnostic service. MATERIAL AND METHODS: Retrospective descriptive sectional study was performed. Clinical records were obtained from the archives of an Oral Diagnostic Service referral center between 2006 and 2016. Data such as gender, age, anatomical location, and diagnosis were collected and categorized. The collected data were submitted to a descriptive analysis and Pearson's chi-square test (p ≤ 0.05). RESULTS: A total of 587 patient records of lip lesions were analyzed. Most lesions were diagnosed in female (52.1%) and adults (56.9%) patients in the lower lip (76.2%). Among all lip lesions, the reactive/inflammatory lesions (n = 238; 40.5%) and oral potentially malignant disorders (n = 164; 28%) were the most frequent group lesions. Mucocele (n = 147; 25%), actinic cheilitis (n = 136; 23.1%) and vascular lesions (n = 51; 8.7%) were the most frequent lesion in the sample. Actinic cheilitis was significant in relation to gender (p < 0.001), all three most frequent lesions were significant in concerning to age group and anatomical site. CONCLUSIONS: Mucocele was the most common lower lip lesion in all age groups, followed by actinic cheilitis and vascular lesions, which mainly affected adults and the elderly.


Assuntos
Queilite , Neoplasias Labiais , Doenças da Boca , Adulto , Idoso , Serviços de Diagnóstico , Feminino , Humanos , Lábio , Estudos Retrospectivos
3.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1631-1638, set.-out. 2019. ilus, mapas
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1038660

RESUMO

The objective of the present study was to establish the bioclimatic zoning by the temperature and humidity index (THI), considering a historical period and a future scenario, in order to represent the thermal environment for broiler breeding in the State of Minas Gerais. A historical series (1976 - 2014) of THI minimum, average and maximum calculated based on data from 48 conventional meteorological stations was used, belonging to the National Institute of Meteorology of the State of Minas Gerais. The analysis of the temporal series was based on the Mann-Kendall test and linear regression. A geostatistical analysis was also carried out to determine the comfort zoning of broilers as a function of the THI intervals. In this way, the THI spatial mapping methodologies and trend analysis for the prediction of a possible future climate scenario can help in the development of risk maps for monitoring thermal comfort of broilers, being indispensable in the planning of actions for the mitigation of the climatic change impacts on the productive chain of the State of Minas Gerais.(AU)


O objetivo do presente trabalho foi estabelecer o zoneamento bioclimático por meio do índice de temperatura e umidade (ITU), considerando-se um período histórico e um cenário futuro, de forma a representar o ambiente térmico para criação de frangos de corte no estado de Minas Gerais. Foi utilizada uma série histórica (1976 - 2014) de ITU mínimo, médio e máximo, que foram calculados com base em dados oriundos de 48 estações meteorológicas convencionais, pertencentes ao Instituto Nacional de Meteorologia do Estado de Minas Gerais. A análise da série temporal se baseou no teste de Mann-Kendall e na regressão linear. Procedeu-se, também, à análise geoestatística para determinação do zoneamento do conforto de frangos de corte segundo os intervalos de ITU. Dessa forma, as metodologias de mapeamento espacial do ITU e a análise de tendência para predição de um possível cenário climático futuro podem auxiliar no desenvolvimento de mapas de risco para o monitoramento do conforto térmico de frangos de corte, sendo indispensáveis no planejamento de ações para mitigação dos impactos das mudanças climáticas sobre a cadeia produtiva do estado de Minas Gerais.(AU)


Assuntos
Animais , Aves Domésticas/crescimento & desenvolvimento , Temperatura , Mudança Climática/estatística & dados numéricos , Galinhas , Umidade
4.
Int Endod J ; 51(6): 674-683, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29226342

RESUMO

AIM: To evaluate the effects of 2.8% or 10% calcium chloride (CaCl2 ) in calcium aluminate cement (CAC) with either bismuth oxide (Bi2 O3 ) or zinc oxide (ZnO) as radiopacifiers on the progression of osteogenic cell cultures. METHODOLOGY: Rat calvaria-derived cells were grown on Thermanox® coverslips for 24 h and exposed to samples of (i) CACb: with 2.8% CaCl2 and 25% Bi2 O3 ; (ii) CACb+: with 10% CaCl2 and 25% Bi2 O3 ; (iii) CACz: with 2.8% CaCl2 and 25% ZnO; or (iv) CACz+: with 10% CaCl2 and 25% ZnO, placed on inserts. Nonexposed cultures served as the control. Calcium and phosphorus contents in culture media were quantified. The effects of the cements on cell apoptosis, cell viability and acquisition of the osteogenic cell phenotype were evaluated. Data were compared by Kruskal-Wallis test (α = 5%). RESULTS: CACb+ promoted the highest levels of calcium in the culture media; CACz+, the lowest levels of phosphorus (P < 0.05). CACz+ and CACb increased cell apoptosis (P < 0.05). CACb reduced cell viability (P < 0.05) and the expression of the osteoblastic phenotype. CACz+ and CACb+ promoted greater cell differentiation and matrix mineralization compared to CACz and CACb (P < 0.05). CONCLUSION: For CAC with the lower CaCl2 content, the use of Bi2 O3 was detrimental for osteoblastic cell survival and differentiation compared to ZnO, while CAC with the higher CaCl2 content supported the acquisition of the osteogenic cell phenotype in vitro regardless of the radiopacifier used. Thus, CAC with 10% CaCl2 would potentially promote bone repair in the context of endodontic therapies.


Assuntos
Compostos de Alumínio/farmacologia , Cloreto de Cálcio/farmacologia , Compostos de Cálcio/farmacologia , Cimentos Dentários/farmacologia , Osteogênese/efeitos dos fármacos , Animais , Apoptose , Bismuto/farmacologia , Sobrevivência Celular , Células Cultivadas , Cimentos Dentários/química , Fenótipo , Ratos , Ratos Wistar , Crânio/citologia , Óxido de Zinco/farmacologia
5.
Int Endod J ; 50(8): 771-779, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27521570

RESUMO

AIM: To evaluate the effect of a calcium aluminate-based cement (CAC+) on the development of the osteogenic phenotype in vitro. METHODOLOGY: Rat calvaria-derived cells were grown on Thermanox® coverslips for 24 h and then exposed to either samples (4-h set) of CAC+ or mineral trioxide aggregate (MTA) placed on Transwell® inserts for periods of up to 14 days. Nonexposed cultures were used as the controls. The comparisons were made using the nonparametric Kruskal-Wallis test, followed by the Student-Newman-Keuls post hoc test when appropriate. RESULTS: The results showed that proximity to MTA or CAC+ samples inhibited cell growth, whereas at a distance, viable and proliferative cells adhered to and spread on the Thermanox® , expressing osteoblast differentiation markers prior to mineralization of the extracellular matrix. Compared with MTA, the osteogenic cell cultures exposed to CAC+ exhibited significantly greater cell viability, alkaline phosphatase (ALP) activity and expression of runt-related transcription factor 2, osterix, ALP, bone sialoprotein and osteocalcin (P < 0.05 for all). For the osteogenic cell cultures exposed to CAC+, the quantification of matrix mineralization was not altered (P > 0.05). CONCLUSIONS: CAC+ supported the acquisition of the osteogenic cell phenotype in vitro, rendering this novel material a potential alternative to MTA in endodontic procedures. Further in vivo studies are needed to verify if the beneficial in vitro effects of CAC+ on osteoblastic cells correspond to an increase and/or acceleration of bone repair in the periapical region.


Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Cimentos Dentários/farmacologia , Osteogênese/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Combinação de Medicamentos , Osteoblastos/efeitos dos fármacos , Óxidos/farmacologia , Ratos Wistar , Silicatos/farmacologia
6.
Oral Dis ; 22(6): 536-42, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27090966

RESUMO

OBJECTIVES: To determine the prevalence of oral potentially malignant disorders (OPMDs) in a population of rural workers in the northeast of Brazil and to investigate the association with sociodemographic, occupational, and health factors. METHODS: A total of 1385 workers answered a validated questionnaire and were examined by calibrated dentists. A descriptive analysis, chi-square homogeneity test, and binary logistic regression were performed. RESULTS: The prevalence of OPMDs was 29.6%. Actinic cheilitis was the most predominant (28.4%), followed by leukoplakia (2.3%) and erythroplakia (0.3%). Gender, type of skin, and time exposed to the sun explained the presence of OPMD (P < 0.0001). The study found increased prevalence, especially for males over the age of 60 years and being exposed to the sun for more than 45 years. CONCLUSION: Rural workers showed high vulnerability to the presence of OPMDs, as estimated prevalence exhibited was high.


Assuntos
Neoplasias Bucais/epidemiologia , População Rural , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Queilite/epidemiologia , Estudos Transversais , Eritroplasia/epidemiologia , Feminino , Humanos , Leucoplasia Oral/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/etiologia , Prevalência
7.
Oral Dis ; 20(3): e31-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23607403

RESUMO

OBJECTIVES: Autografts from mandibular symphysis and ramus are often used for bone reconstruction. Based on this, we hypothesized that these sites could be useful cell sources for bone tissue engineering approaches. Thus, our study aimed at evaluating the proliferation and osteoblast phenotype development of cells derived from mandibular symphysis and ramus. MATERIALS AND METHODS: Cells were isolated from bone fragments of four patients by enzymatic digestion and cultured under osteogenic condition for up to 17 days. Cultures were assayed for cell proliferation, gene expression of key bone markers runt-related transcription factor 2 (Runx2), distal-less homeobox 5 (DLX5), SATB homeobox 2 (SATB2), Osterix (OSX), family with sequence similarity 20, member C (FAM20C), bone sialoprotein (BSP), osteopontin (OPN) and osteocalcin (OC), alkaline phosphatase (ALP) expression and activity, and extracellular matrix mineralization. Data were compared by two-way ANOVA or t-test for independent samples when appropriate. RESULTS: Cells derived from ramus displayed lower proliferative activity and higher gene expression of Runx2, DLX5, SATB2, OSX, FAM20C, BSP, OPN and OC, ALP protein expression and activity and extracellular matrix mineralization compared with symphysis-derived cells. CONCLUSION: Symphysis and ramus may be considered as cell sources for bone tissue engineering approaches but due to the higher osteogenic potential, ramus-derived cells are more appealing for constructing cell-based biomaterials.


Assuntos
Osso e Ossos , Mandíbula/citologia , Osteoblastos/citologia , Engenharia Tecidual/métodos , Proliferação de Células , Células Cultivadas , Humanos , Osteoblastos/transplante , Osteogênese/genética , Fenótipo
8.
J Cell Biochem ; 115(3): 540-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24122940

RESUMO

The aim of our study was to investigate the osteoinductive potential of a titanium (Ti) surface with nanotopography, using mesenchymal stem cells (MSCs) and the mechanism involved in this phenomenon. Polished Ti discs were chemically treated with H2 SO4 /H2 O2 to yield nanotopography and rat MSCs were cultured under osteogenic and non-osteogenic conditions on both nanotopography and untreated polished (control) Ti surfaces. The nanotopography increased cell proliferation and alkaline phosphatase (Alp) activity and upregulated the gene expression of key bone markers of cells grown under both osteogenic and non-osteogenic conditions. Additionally, the gene expression of α1 and ß1 integrins was higher in cells grown on Ti with nanotopography under non-osteogeneic condition compared with control Ti surface. The higher gene expression of bone markers and Alp activity induced by Ti with nanotopography was reduced by obtustatin, an α1ß1 integrin inhibitor. These results indicate that α1ß1 integrin signaling pathway determines the osteoinductive effect of nanotopography on MSCs. This finding highlights a novel mechanism involved in nanosurface-mediated MSCs fate and may contribute to the development of new surface modifications aiming to accelerate and/or enhance the process of osseointegration.


Assuntos
Integrina alfa1beta1/genética , Células-Tronco Mesenquimais/citologia , Nanotecnologia , Osteoblastos/citologia , Titânio/química , Animais , Adesão Celular/genética , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Integrina alfa1beta1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteogênese/genética , Ratos , Transdução de Sinais/efeitos dos fármacos , Propriedades de Superfície , Venenos de Víboras/farmacologia
9.
Int J Oral Maxillofac Surg ; 41(11): 1361-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22633468

RESUMO

The objective of this study was to compare the bone repair along a mandibular body osteotomy stabilized with 2.0 mm absorbable and metallic systems. 12 male, adult mongrel dogs were divided into two groups (metallic and absorbable) and subjected to unilateral osteotomy between the mandibular third and fourth premolars, which was stabilized by applying two 4-hole plates. At 2 and 18 weeks, three dogs from each group were killed and the osteotomy sites were removed and divided equally into three parts: the upper part was labelled the tension third (TT), the lower part the compression third (CT), and the part between the TT and CT the intermediary third (IT). Regardless of the treatment system, union between the fragments was observed at 18 weeks and the CT showed more advanced stages of bone repair than the TT. Histometric analysis did not reveal any significant differences among the 3 parts or systems in the distance between bone fragments at 2 weeks. Although at 18 weeks the proportions of newly formed bone did not differ among TT, IT and CT, significantly enhanced bone formation was observed in all sections for the metallic group. The patterns of repair were distinct between treatments.


Assuntos
Materiais Biocompatíveis , Fixadores Internos , Mandíbula/cirurgia , Metais , Osteotomia , Animais , Cães
10.
Int J Oral Maxillofac Surg ; 41(9): 1097-101, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22487807

RESUMO

This study investigated the effect of pore size on osteoblastic phenotype development in cultures grown on porous titanium (Ti). Porous Ti discs with three different pore sizes, 312 µm (Ti 312), 130 µm (Ti 130) and 62 µm (Ti 62) were fabricated using a powder metallurgy process. Osteoblastic cells obtained from human alveolar bone were cultured on porous Ti samples for periods of up to 14 days. Cell proliferation was affected by pore size at day 3 (p=0.0010), day 7 (p=0.0005) and day 10 (p=0.0090) in the following way: Ti 62

Assuntos
Proliferação de Células , Osteoblastos/citologia , Titânio/química , Adulto , Processo Alveolar/citologia , Técnicas de Cultura de Células , Diferenciação Celular , Células Cultivadas , Humanos , Masculino , Porosidade , Propriedades de Superfície , Adulto Jovem
11.
J Mater Sci Mater Med ; 22(1): 151-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21107658

RESUMO

This study investigated the response of human alveolar bone-derived cells to a novel poly(vinylidene fluoride-trifluoroethylene)/barium titanate (P(VDF-TrFE)/BT) membrane. Osteoblastic cells were cultured in osteogenic conditions either on P(VDF-TrFE)/BT or polytetrafluoroethylene (PTFE) for up to 14 days. At 7 and 14 days, the mRNA expression of Runt-related transcription factor 2 (RUNX2), Type I collagen (COL I), Osteopontin (OPN), Alkaline phosphatase (ALP), Bone sialoprotein (BSP), and Osteocalcin (OC), key markers of the osteoblastic phenotype, and of Bcl2-associated X protein (Bax), B-cell CLL/lymphoma 2 (Bcl-2), and Survivin (SUR), associated with the control of the apoptotic cell death, was assayed by real-time PCR. In situ ALP activity was qualitatively evaluated by means of Fast red staining. Surface characterization was also qualitatively and quantitatively assayed in terms of topography, roughness, and wettability. Cells grown on P(VDF-TrFE)/BT exhibited a significantly higher mRNA expression for all markers compared to the ones on PTFE, except for Bcl-2, which was not detected for both groups. Additionally, Fast red staining was noticeably stronger in cultures on P(VDF-TrFE)/BT at 7 and 14 days. At micron- and submicron scale, SEM images and roughness analysis revealed that PTFE and P(VDF-TrFE)/BT exhibited a smooth topography and a similar roughness, respectively. PTFE membrane displayed higher contact angles compared with P(VDF-TrFE)/BT, as indicated by wettability assay. The novel P(VDF-TrFE)/BT membrane supports the acquisition of the osteoblastic phenotype in vitro, while up-regulating the expression of apoptotic markers. Further in vivo experiments should be carried out to confirm the capacity of P(VDF-TrFE)/BT membrane in promoting bone formation in guided bone regeneration.


Assuntos
Compostos de Bário/química , Osso e Ossos/efeitos dos fármacos , Membranas Artificiais , Polivinil/química , Titânio/química , Alvéolo Dental/citologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Compostos de Bário/farmacologia , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/genética , Regeneração Óssea/fisiologia , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Genes bcl-2/efeitos dos fármacos , Regeneração Tecidual Guiada , Humanos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/fisiologia , Polivinil/farmacologia , Titânio/farmacologia
12.
Acta Biomater ; 6(3): 979-89, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19703597

RESUMO

The aim of this work was to evaluate the biocompatibility of poly(vinylidene fluoride-trifluoroethylene)/barium titanate (P(VDF-TrFE)/BT) membrane to be used in guided tissue regeneration (GTR). Fibroblasts from human periodontal ligament (hPDLF) and keratinocytes (SCC9) were plated on P(VDF-TrFE)/BT and polytetrafluorethylene membranes at a cell density of 20,000 cells well(-1) and cultured for up to 21 days. Cell morphology, adhesion and proliferation were evaluated in hPDLF and keratinocytes, while total protein content and alkaline phosphatase (ALP) activity were assayed only for hPDLF. Using a higher cell density, real-time polymerase chain reaction (PCR) was performed to assess the expression of typical genes of hPDLF, such as periostin, PDLs17, S100A4 and fibromodulin, and key phenotypic markers of keratinocytes, including involucrin, keratins 1, 10 and 14. Expression of the apoptotic genes bax, bcl-2 and survivin was evaluated for both cultures. hPDLF adhered and spread more on P(VDF-TrFE)/BT, whereas keratinocytes showed a round shape on both membranes. hPDLF adhesion was greater on P(VDF-TrFE)/BT at 2 and 4h, while keratinocyte adhesion was similar for both membranes. Whereas proliferation was significantly higher for hPDLF on P(VDF-TrFE)/BT at days 1 and 7, no signs of keratinocyte proliferation could be noticed for both membranes. Total protein content was greater on P(VDF-TrFE)/BT at 7, 14 and 21 days, and higher levels of ALP activity were observed on P(VDF-TrFE)/BT at 21 days. Real-time PCR revealed higher expression of phenotypic markers of hPDLF and keratinocytes as well as greater expression of apoptotic genes in cultures grown on P(VDF-TrFE)/BT. These results indicate that, by favoring hPDLF adhesion, spreading, proliferation and typical mRNA expression, P(VDF-TrFE)/BT membrane should be considered an advantageous alternative for GTR.


Assuntos
Compostos de Bário/química , Materiais Biocompatíveis/química , Fibroblastos/fisiologia , Regeneração Tecidual Guiada Periodontal/métodos , Hidrocarbonetos Fluorados/química , Queratinócitos/fisiologia , Ligamento Periodontal/fisiologia , Polivinil/química , Titânio/química , Células Cultivadas , Fibroblastos/citologia , Humanos , Queratinócitos/citologia , Teste de Materiais , Ligamento Periodontal/citologia
13.
Anat Histol Embryol ; 36(5): 371-4, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17845228

RESUMO

The microscopic description of the teeth of pacas (Agouti paca) bred in captivity was developed for providing biological data on one of the largest American wild rodents, as not many references exist in the literature about this species. Two newborn males, two adult males (9 and 72 months old), one newborn female and two adult females (30 and 54 months old) were used after death due to fights, neonatal cannibalism or unknown causes. Animals were radiographed, and their teeth were extracted and put on an acrylic resin block, cut on a diamond-like disc microtome and diaphanized. It was noted that enamel surrounds the coronary dentine and projects to the root region, besides being present as internal laminae, arranged in a parallel way and in the vestibulolingual direction. The dentine is located between the enamel laminae and surrounds the pulp horns. The cementum is located internal to the enamel laminae. From scanning electronic microscopy, we find that the enamel is the outer element on the vestibular surface, and it is in direct contact with the dentine. On the lingual surface, the cementum and dentine are the outer elements.


Assuntos
Roedores/anatomia & histologia , Dente/anatomia & histologia , Dente/ultraestrutura , Animais , Esmalte Dentário/anatomia & histologia , Esmalte Dentário/ultraestrutura , Dentina/anatomia & histologia , Dentina/ultraestrutura , Feminino , Masculino , Microscopia Eletrônica de Transmissão
14.
Anat Histol Embryol ; 35(5): 316-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16968251

RESUMO

Two newborn males, two adult males 9 and 72 months old, one newborn female and two adult females of 30 and 54 months old pacas were used. Animals were radiographed on lateral recumbency, teeth were extracted and the vestibulolingual and mesiodistal lengths were achieved at the occlusal surface, besides the longitudinal length. The lower incisors presented greater length in relation to the other ones and sinuous shape; the upper incisors, relatively smaller, are practically straight. There is no canine tooth, and after a great diastema there is one premolar and three molars in each hemiarcade. In adult pacas, the enamel of incisors presents yellowish colour, mainly in the labial surface; in the premolars and molars, the enamel is present as internal sheets disposed nearly in a parallel way and in vestibulolingual direction, through practically all the dental length, which provides several joined teeth aspect.


Assuntos
Roedores/anatomia & histologia , Dente/anatomia & histologia , Animais , Dente Canino/anatomia & histologia , Esmalte Dentário/anatomia & histologia , Feminino , Incisivo/anatomia & histologia , Masculino , Coroa do Dente/anatomia & histologia , Raiz Dentária/anatomia & histologia
15.
J Mater Sci Mater Med ; 13(11): 1071-5, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15348178

RESUMO

The aim of this study was to determine the relationship between changes in microporosity and the osseointegration and the osseoconductivity of hydroxyapatite (HAp). HAp cylinders were manufactured by a combination of uniaxial powder pressing and different sintering conditions, with different percentages of microporosity: HAp-I with 3.96+/-0.75% microporosity, HAp-II with 15.66+/-1.60% microporosity, and HAp-III with 29.72+/-0.69% microporosity. These HAp cylinders were surgically implanted in rabbit femurs. After 8 and 12 weeks, the femurs were removed, fixed, sectioned, ground, and stained by Stevenel's blue/Van Gieson for light microscopy and histomorphometry. Some ground sections were routinely processed for SEM. The osseointegration and the osseoconductivity were determined by means of image analysis and the data were submitted to ANOVA. In all cases the cortical bone was repaired and the HAp facing the medullary canal was lined with endosteum, which in some areas exhibited thin bone tissue formation. SEM observations showed no differences in the morphology of tissue-HAp interfaces for the three different porosities of HAp. There were no statistical differences between the groups related to either osseointegration or osseoconductivity. These results suggest that neither osseointegration nor osseoconductivity of HAp are influenced by changes in HAp microporosity.

16.
Virchows Arch ; 439(4): 571-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11710645

RESUMO

We have already demonstrated that a reconstituted basement membrane (Matrigel) is a key modulator of morphogenetic changes and cytodifferentiation of pleomorphic adenoma cells in culture. Myoepithelioma is considered to be a neoplasm closely related to pleomorphic adenoma and should experience similar induction processes. Thus, the aim of this study was to investigate whether Matrigel would influence myoepithelioma cells. We used a cell line derived from a human salivary gland plasmacytoid myoepithelioma (M1 cells) grown in a three-dimensional preparation of Matrigel. Phenotype differences were assessed using conventional light microscopy technique (haematoxylin and eosin) and phase and differential interference contrast (Nomarski). Immunofluorescence was carried out to detect smooth-muscle actin, laminin and type-IV collagen. M1 cells exhibited all proteins studied, showing a myoepithelial differentiation. M1 cells grown inside Matrigel presented morphological changes and changes in smooth-muscle actin status. By growing M1 cells inside Matrigel, it was possible to reproduce the tumour architecture with no duct-like structures. Based on our findings, we suggest that myoepithelioma would be derived from a cell with a commitment to myoepithelial differentiation. We also suggest that the mechanical properties of the matrix environment will likely regulate smooth-muscle actin expression in myoepithelioma.


Assuntos
Materiais Biocompatíveis/metabolismo , Colágeno , Combinação de Medicamentos , Matriz Extracelular/metabolismo , Laminina , Mioepitelioma/patologia , Proteoglicanas , Neoplasias das Glândulas Salivares/patologia , Actinas/análise , Actinas/metabolismo , Colágeno Tipo IV/análise , Colágeno Tipo IV/metabolismo , Meios de Cultura , Técnica Direta de Fluorescência para Anticorpo , Humanos , Laminina/análise , Laminina/metabolismo , Mioepitelioma/química , Mioepitelioma/metabolismo , Neoplasias das Glândulas Salivares/química , Neoplasias das Glândulas Salivares/metabolismo , Células Tumorais Cultivadas
17.
J Periodontol ; 72(5): 612-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11394396

RESUMO

BACKGROUND: The purpose of this study was to evaluate the influence of root trunk concavities on guided tissue regeneration. METHODS: The second, third, and fourth mandibular bicuspids of 4 healthy mongrel dogs were used. Full flaps were elevated and furcation lesions (5 mm in height and 2 mm in depth) were surgically created. One mm deep concavities were prepared on the root trunks and part of the crown of all teeth. The second bicuspids remained as controls (C); the left third and fourth bicuspids received normal expanded polytetrafluoroethylene (ePTFE) membranes (NM) and the right bicuspids received modified ePTFE membranes (MM). The MM were made by removing the collar from an NM, cutting it into 2 mm segments, and suturing each of the segments to the collar of each MM. Normal and modified membranes were sutured to their corresponding teeth and the flaps sutured. After the healing period, the mandibles were removed and the teeth processed for histomorphometry. RESULTS: The results showed that the junctional epithelium measured a mean of 0.71 mm for C, 0.64 mm for NM, and 0.14 mm for MM. The differences between C and MM and between NM and MM were both statistically significant at the 5% level (Kruskal-Wallis test). Mean bone height measurements for the buccal surfaces from the furcation roofs were 2.79 mm for C, 2.60 mm for NM, and 1.06 mm for MM and for the mid-portion 1.10 mm for C, 1.23 mm for NM, and 0.30 mm for MM. Differences were statistically significant at the 1% level between C and MM and between NM and MM for the buccal measurements, and at the 5% level between NM and MM for the mid-portion measurements. CONCLUSIONS: Root trunk concavities are important risk factors for regenerative procedures. The collars of the membranes should be modified to improve results when concavities are present.


Assuntos
Defeitos da Furca/cirurgia , Regeneração Tecidual Guiada Periodontal , Raiz Dentária/patologia , Processo Alveolar/patologia , Animais , Dente Pré-Molar/patologia , Tecido Conjuntivo/patologia , Cemento Dentário/patologia , Cães , Inserção Epitelial/patologia , Desenho de Equipamento , Defeitos da Furca/classificação , Regeneração Tecidual Guiada Periodontal/métodos , Membranas Artificiais , Ligamento Periodontal/patologia , Politetrafluoretileno/química , Fatores de Risco , Estatística como Assunto , Estatísticas não Paramétricas , Propriedades de Superfície , Técnicas de Sutura , Colo do Dente/patologia , Coroa do Dente/patologia , Cicatrização
18.
Oral Oncol ; 37(3): 326-31, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11287290

RESUMO

We present four new cases of verruciform xanthoma (VX) in the oral mucosa and review the literature. Clinical, histological, and immunohistochemical features of four new cases of VX were analysed together with cases found in a review of the literature. Expression of CD-68 was studied by immunohistochemistry. Only 162 cases were reported in the oral mucosa. Ninety were males (55.5%) and 72 were females (44.5%). Mean age was 44.9 years. The majority of cases occurred in masticatory mucosa (69.7%). Our cases exhibited papillary or verrucous proliferation of squamous epithelium associated with hyperparakeratosis and with numerous foamy cells confined to the lamina propria papillae. Foamy cells were positive to CD-68 antibody, showing a macrophagic nature. VX is a rare benign lesion, and is probably inflammatory. However, its aetiology and pathological mechanisms remain unknown.


Assuntos
Doenças da Boca/patologia , Mucosa Bucal/patologia , Xantomatose/patologia , Adulto , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Biomarcadores/análise , Células Espumosas/química , Células Espumosas/patologia , Humanos , Imuno-Histoquímica , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Doenças da Boca/imunologia , Mucosa Bucal/imunologia , Xantomatose/imunologia
19.
J Periodontol ; 72(12): 1734-41, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11811510

RESUMO

BACKGROUND: Due to its concave morphology, a COL creates difficulties for proper oral hygiene. When this characteristic is accentuated by tooth position or caries and when restorations are necessary, they should be corrected by preprosthetic surgery. However, there are no data proving the efficacy of the procedures. The purpose of this study was to evaluate tissue response to preprosthetic surgery to modify COL morphology. METHODS: Five mongrel dogs received apically positioned flaps, osteotomy/plasty, and RAI (restorative alveolar interface technique) on the maxillary right third bicuspid and first molar; on the same teeth on the left side, a large tissue excision similar to gingivectomy and RAI were performed. Histologic specimens stained with hematoxylin and eosin and Mallory were evaluated at hour 0 and 1, 2, 3, and 4 weeks under light microscopy. RESULTS: At hour 0, hemorrhage in the remaining interproximal tissue on the left side, and denuded bone modified by the osteotomy on the right side, were observed. At 1 week, both sides showed the presence of granulation tissue and the beginning of reepithelialization and fiber formation. At 2 weeks, the papillae were rebuilt and epithelialized, with fewer inflammatory cells and dilated blood vessels, with a convex morphology. At 3 weeks, the papillae were convex and saddle shaped, with thicker epithelium and denser connective tissue. The general aspect was similar to attached gingiva. However, on the right side, the total extension of the interproximal tissues was longer and had a less accentuated convex curvature. At 4 weeks, the tissues were more mature, but the morphologic and histological findings were similar to 3 weeks. CONCLUSION: Both techniques modified the COL morphology, suggesting that the RAI technique was effective; but the apically positioned flap with osteotomy and RAI created a more extensive convex surface and more interproximal space for the prosthesis. It is recommended that this technique be considered for use in humans.


Assuntos
Gengiva/cirurgia , Gengivectomia/métodos , Procedimentos Cirúrgicos Pré-Protéticos Bucais/métodos , Processo Alveolar/cirurgia , Alveolectomia/métodos , Animais , Cães , Masculino , Osteotomia/métodos , Retalhos Cirúrgicos
20.
Artigo em Inglês | MEDLINE | ID: mdl-9127381

RESUMO

The glandular odontogenic cyst is a rare lesion that was recognized as a distinct entity in the latest WHO typing of odontogenic tumors. We report a glandular odontogenic cyst that recurred after surgical removal from the anterior mandible of a 54-year-old white man. Immunohistochemical study showed that the cystic epithelium reacted positively to antibodies directed against cytokeratins (CKs) 7, 13, 14, and 19 and negatively to CKs 8 and 18.


Assuntos
Doenças Mandibulares/patologia , Cistos Odontogênicos/patologia , Epitélio/patologia , Humanos , Queratinas/biossíntese , Masculino , Doenças Mandibulares/metabolismo , Pessoa de Meia-Idade , Cistos Odontogênicos/metabolismo
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