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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

In vitro and in vivo studies of tissue engineering in reconstructive plastic surgery

Huss, Fredrik R.M. January 2005 (has links)
To correct, improve, and maintain tissues, and their functions, are common denominators in tissue engineering and reconstructive plastic surgery. This can be achieved by using autolo-gous tissues as in flaps or transplants. However, often autologous tissue is not useable. This is one of the reasons for the increasing interest among plastic surgeons for tissue engineering, and it has led to fruitful cross-fertilizations between the fields. Tissue engineering is defined as an interdisciplinary field that applies the principles of engineering and life sciences for development of biologic substitutes designed to maintain, restore, or improve tissue functions. These methods have already dramatically improved the possibilities to treat a number of medical conditions, and can arbitrarily be divided into two main principles: > Methods where autologous cells are cultured in vitro and transplanted by means of a cell suspension, a graft, or in a 3-D biodegradable matrix as carrier. > Methods where the tissue of interest is stimulated and given the right prerequisites to regenerate the tissue in vivo/situ with the assistance of implantation of specially designed materials, or application of substances that regulate cell functions - guided tissue regeneration. We have shown that human mammary epithelial cells and adipocytes could be isolated from tissue biopsies and that the cells kept their proliferative ability. When co-cultured in a 3-D matrix, patterns of ductal structures of epithelial cells embedded in clusters of adipocytes, mimicking the in vivo architecture of human breast tissue, were seen. This indicated that human autologous breast tissue can be regenerated in vitro. The adipose tissue is also generally used to correct soft tissue defects e.g. by autologous fat transplantation. Alas 30-70% of the transplanted fat is commonly resorbed. Preadipocytes are believed to be hardier and also able to replicate, and hence, are probably more useful for fat transplantation. We showed that by using cell culture techniques, significantly more pre-adipocytes could survive and proliferate in vitro compared to two clinically used techniques of fat graft handling. Theoretically, a biopsy of fat could generate enough preadipocytes to seed a biodegradable matrix that is implanted to correct a defect. The cells in the matrix will replicate at a rate that parallels the vascular development, the matrix subsequently degrades and the cell-matrix complex is replaced by regenerated, vascularized adipose tissue. We further evaluated different biodegradable scaffolds usable for tissue engineering of soft tissues. A macroporous gelatin sphere showed several appealing characteristics. A number of primary human ecto- and mesodermal cells were proven to thrive on the gelatin spheres when cultured in spinner flasks. As the spheres are biodegradable, it follows that the cells can be cultured and expanded on the same substrate that functions as a transplantation vehicle and scaffold for tissue engineering of soft tissues. To evaluate the in vivo behavior of cells and gelatin spheres, an animal study was performed where human fibroblasts and preadipocytes were cultured on the spheres and injected intra-dermally. Cell-seeded spheres were compared with injections of empty spheres and cell suspensions. The pre-seeded spheres showed a near complete regeneration of the soft tissues with neoangiogenesis. Some tissue regeneration was seen also in the ‘naked’ spheres but no effect was shown by cell injections. In a human pilot-study, intradermally injected spheres were compared with hyaluronan. Volume-stability was inferior to hyaluronan but a near complete regeneration of the dermis was proven, indicating that the volume-effect is permanent in contrast to hyaluronan which eventually will be resorbed. Further studies are needed to fully evaluate the effect of the macroporous gelatin spheres, with or without cellular pre-seeding, as a matrix for guided tissue regeneration. However, we believe that the prospect to use these spheres as an injectable, 3D, biodegradable matrix will greatly enhance our possibilities to regenerate tissues through guided tissue regeneration. / On the day of the defence date the status of article V was In Press.
12

Craniofacial periosteal cell capacities /

Ochareon, Pannee, January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 205-223).
13

Regeneration in periodontal and endosseous implant treatment

Mayfield, Lisa. January 1998 (has links)
Thesis (doctoral)--Lunds Universitet, Malmö, 1998. / Added t.p. and errata sheet inserted. Includes bibliographical references.
14

Regeneration in periodontal and endosseous implant treatment

Mayfield, Lisa. January 1998 (has links)
Thesis (doctoral)--Lunds Universitet, Malmö, 1998. / Added t.p. and errata sheet inserted. Includes bibliographical references.
15

Análise do processo de reparo ósseo de cavidades cirúrgicas preenchidas com osso autógeno e recobertas por membrana de matriz óssea homógena e de politetrafluoretileno em ratos

Borrasca, Albanir Gabriel [UNESP] 12 August 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-12Bitstream added on 2014-06-13T19:47:14Z : No. of bitstreams: 1 borrasca_ag_dr_araca.pdf: 844710 bytes, checksum: d1c813312e1b09f119604bb41d9ee6ab (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Proposição: O objetivo deste trabalho foi avaliar, qualitativa e quantitativamente, o comportamento da membrana de matriz óssea homógena desmineralizada e conservada em glicerinae e membrana de Ptfe no processo de reparo ósseo de cavidades cirúrgicas preenchidas com osso autógeno realizadas em tíbias de ratos Material e Métodos: Foram utilizados 60 ratos (Rattus norvegicus albinus, Wistar) machos, com aproximadamente 250 gramas divididos em três grupos: o grupo I (Controle-sem membrana), grupo II (membrana homógena) e grupo III (membrana de ptfe). Após tricotomia, anestesia e antissepsia foi realizada uma incisão longitudinal nas regiões antero-laterais de cada tibia. Após exposição das tíbias, duas cavidades cirúrgicas de 2mm de diâmetro foram preparadas com trefina em baixa-rotação refrigerada, uma no membro posterior esquerdo e outra no membro posterior direito, sendo a primeira preenchida com o osso autógeno particulado coletado durante a realização das duas cavidades e recobertas pelas membranas utilizadas no estudo. Aos 10 e 60 dias pós-operatórios os animais foram eutanaziados e as peças obtidas foram processadas laboratorialmente para a realização de cortes semi-seriados com seis micrômetros de espessura e corados pela hematoxilina e eosina para análise histomorfométrica. Resultados e Conclusão: A membrana homógena mostrou-se biocompatível e cumpriu sua função e em termos de área óssea neoformada as membranas obtiveram desempenho semelhantes / Purpose: The aim of this study was to evaluate the behavior of membrane of a demineralized homogenous bone matrix and preserved in glycerin and the Ptfe membrane in the process of bony repair of surgical cavities filled out with autogenous bone accomplished in tibias rats. Materials and Methods: Sixty male rats weighing approximately 250 g were selected and assigned to two groups, as follows. Group I (without membrane), Group II (homogenous membrane) and Group III ( Ptfe membrane). After anesthesia, shaving and antisepsis, a longitudinal incision was made in the anterolateral areas of each tibia. After exhibition of the tibias, two surgical cavities of 2mm of diameter were prepared with trefina in refrigerated low-rotation, one in the left posterior member, other in the right subsequent member, being the first filled out with particulate autogenous bone collected during the accomplishment of the two cavities and covered with the membrane. Ten and sixty days postoperatively, the animals were euthanized and the anatomical pieces were submitted to routine laboratorial processing and serially sectioned to obtain 6-μm-thick sections, which were stained by hematoxylin and eosin for histomorphometric analysis. Results and Conclusions: The homogenous membrane proved to be biocompatible and fulfilled its function and in terms of bone area formation membranes had similar performance
16

Análise do processo de reparo ósseo de cavidades cirúrgicas preenchidas com osso autógeno e recobertas por membrana de matriz óssea homógena e de politetrafluoretileno em ratos /

Borrasca, Albanir Gabriel. January 2011 (has links)
Orientador: Osvaldo Magro Filho / Coorientador: Alessandra Marcondes Aranega / Banca: Edmur Aparecido Callestini / Banca: Eleonor Álvaro Garbin Júnior / Banca: Daniela Ponzoni / Banca: Celso Koogi Sonoda / Resumo: Proposição: O objetivo deste trabalho foi avaliar, qualitativa e quantitativamente, o comportamento da membrana de matriz óssea homógena desmineralizada e conservada em glicerinae e membrana de Ptfe no processo de reparo ósseo de cavidades cirúrgicas preenchidas com osso autógeno realizadas em tíbias de ratos Material e Métodos: Foram utilizados 60 ratos (Rattus norvegicus albinus, Wistar) machos, com aproximadamente 250 gramas divididos em três grupos: o grupo I (Controle-sem membrana), grupo II (membrana homógena) e grupo III (membrana de ptfe). Após tricotomia, anestesia e antissepsia foi realizada uma incisão longitudinal nas regiões antero-laterais de cada tibia. Após exposição das tíbias, duas cavidades cirúrgicas de 2mm de diâmetro foram preparadas com trefina em baixa-rotação refrigerada, uma no membro posterior esquerdo e outra no membro posterior direito, sendo a primeira preenchida com o osso autógeno particulado coletado durante a realização das duas cavidades e recobertas pelas membranas utilizadas no estudo. Aos 10 e 60 dias pós-operatórios os animais foram eutanaziados e as peças obtidas foram processadas laboratorialmente para a realização de cortes semi-seriados com seis micrômetros de espessura e corados pela hematoxilina e eosina para análise histomorfométrica. Resultados e Conclusão: A membrana homógena mostrou-se biocompatível e cumpriu sua função e em termos de área óssea neoformada as membranas obtiveram desempenho semelhantes / Abstract: Purpose: The aim of this study was to evaluate the behavior of membrane of a demineralized homogenous bone matrix and preserved in glycerin and the Ptfe membrane in the process of bony repair of surgical cavities filled out with autogenous bone accomplished in tibias rats. Materials and Methods: Sixty male rats weighing approximately 250 g were selected and assigned to two groups, as follows. Group I (without membrane), Group II (homogenous membrane) and Group III ( Ptfe membrane). After anesthesia, shaving and antisepsis, a longitudinal incision was made in the anterolateral areas of each tibia. After exhibition of the tibias, two surgical cavities of 2mm of diameter were prepared with trefina in refrigerated low-rotation, one in the left posterior member, other in the right subsequent member, being the first filled out with particulate autogenous bone collected during the accomplishment of the two cavities and covered with the membrane. Ten and sixty days postoperatively, the animals were euthanized and the anatomical pieces were submitted to routine laboratorial processing and serially sectioned to obtain 6-μm-thick sections, which were stained by hematoxylin and eosin for histomorphometric analysis. Results and Conclusions: The homogenous membrane proved to be biocompatible and fulfilled its function and in terms of bone area formation membranes had similar performance / Doutor
17

O efeito do fator de crescimento de fibroblastos básico aplicado em superfícies radiculares condicionadas com cloridrato de tetraciclina ou EDTA na morfologia e densidade de fibroblastos. Estudo in vitro

Silvério, Karina Gonzales [UNESP] 01 March 2002 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-03-01Bitstream added on 2014-06-13T18:07:24Z : No. of bitstreams: 1 silverio_kg_me_arafo.pdf: 1644294 bytes, checksum: 5d943591d5c51a3846c75163db9a2ebb (MD5) / O objetivo do presente estudo foi avaliar in vitro o efeito do condicionamento radicular com fator de crescimento de fibroblastos básico (b-FGF) sobre a morfologia e densidade de fibroblastos. Para tal, blocos de dentina com 4 mm2 de área de superfície foram obtidos de raízes de dentes humanos extraídos devido severo envolvimento periodontal, sendo instrumentados manualmente e autoclavados. Noventa amostras foram selecionadas aleatoriamente e distribuídas em 3 grupos segundo o tratamento de superfície prévio ao condicionamento com o b-FGF: sem tratamento - controle; 50 mg/mL de cloridrato de tetraciclina e EDTA a 24%. As 30 amostras de cada um destes 3 grupos foram distribuídas em 3 subgrupos quanto à dose de b-FGF: 0 æg/mL - controle; 50 æg/mL e 125 æg/mL. Após os tratamentos, as amostras foram incubadas a 37º C e 98% de umidade com 2mL de meio Eagle, sendo 1mL com fibroblastos de linhagem contínua (células McCoy) na concentração de 1 x 105 células/mL e 1mL meio sem células, por 24 h. Após as 24 h, as amostras foram submetidas a preparo de rotina para MEV e então, fotomicrografadas nos aumentos de 500X (densidade celular) e 1000X (morfologia celular). Em seguida, as fotomicrografias foram avaliadas por 3 examinadores treinados, calibrados, independentes e cegos, os quais verificaram morfologia e densidade celular segundo os escores propostos por Gamal et al. (1998) e Jenkins et al. (1988), respectivamente. A aplicação da Análise de Regressão pela Técnica da Árvore demonstrou haver diferenças estatisticamente significantes para a densidade celular (p<0,0001) entre os grupos EDTA, tetraciclina e controle, sendo que também houve diferenças entre as doses de 0/50 æg e 125 æg de b-FGF nas amostras condicionadas com EDTA (p<0,0001) e entre as doses de 0 e 50/125 æg de b-FGF nas amostras condicionadas com tetraciclina... . / The aim of this study was to evaluate in vitro the effect of the root surface conditioning with basic fibroblast growth factor (b-FGF) about morphology and density of fibroblasts. Dentin slices of with 4 mm2 of surface area were obtained from roots of teeth extracted due to severe periodontal involvment. These were scaled and sterilized. Ninety samples were randomly distributed into 3 groups according to treatment before application of b-FGF: non-treated - control; 50mg/mL of tetracycline HCl and EDTA 24%. The thirty samples of each group were distributed into 3 subgroups according to the concentration of b-FGF: 0 æg/mL - control; 50 æg/mL and 125 æg/mL. After treatments, the samples were incubated at 37ºC and 98% humidity with 1mL of Eagle Medium with 1 x 105 cells/mL of fibroblast from continuos lineage (McCoy Cells) plus 1mL this solution without cells during 24 hours. The samples were submitted to routine preparation for SEM and photographed at 500x (density celular) and 1000x (morphology celular). Three independent and blind examiners evaluated the fibroblast`s morphology and density, according to Gamam et al. (1998) and Jenkins et al. (1998), respectively. Classification and Regression Trees test results indicated significant differences on the density (p<0,0001) among EDTA, tetracycline and control groups with also differences between concentrations of 0/50æg and 125æg of b-FGF at the samples conditioning with EDTA (p<0,0001) and between concentrations of 0 and 50/125 æg of b-FGF at the samples conditioning with tetracycline(p<0,0001). The results of this test to morphology indicated significant differences between treatment or non-treatment with b-FGF, and that concentration of 125 æg demonstrated to be more favorable than the concentration of 50 æg. In conclusion, the treatment of root surfaces with b-FGF influenced the density... (Complete abstract, click electronic address below).
18

Técnica de retalho semilunar posicionado coronariamente com ou sem associação à proteína derivada das matriz do esmalte para o tratamento de recessões gengivais : estudo clínico controlado randomizado / Semilunar coronally positioned flap with or without enamel matrix derivative for the treatment of gingival recessions : randomized controlled clinical trial

França, Isabela Lima, 1987- 02 March 2015 (has links)
Orientador: Enilson Antonio Sallum / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-26T23:34:09Z (GMT). No. of bitstreams: 1 Franca_IsabelaLima_M.pdf: 1330190 bytes, checksum: 6782efacdca31e69f907222817356c7c (MD5) Previous issue date: 2015 / Resumo: O objetivo deste estudo foi avaliar, clinicamente, a utilização do Retalho Semilunar Posicionado Coronariamente (RSPC) para tratamento de recessões gengivais, com ou sem associação à proteína derivada da matriz do esmalte (EMD). Foram selecionados 30 pacientes, que foram randomizados e alocados em dois grupos: teste (RSPC + EMD) e controle (RSPC sozinho). Para serem incluídos no estudo, os indivíduos deveriam apresentar recessões gengivais vestibulares localizadas classe I de Miller com altura maior ou igual a 2,0mm e menor que 4,0 mm, em caninos ou pré-molares superiores. Parâmetros clínicos avaliados: altura da recessão gengival (ARG), largura da recessão gengival (LRG), nível de inserção clínica (NIC), profundidade de sondagem (PS), altura de tecido queratinizado (ATQ), espessura de tecido queratinizado (ETQ) e altura (AP) e largura (LP) das papilas mesial e distal, além de índice de placa (IPL) e índice gengival (IG). Estes parâmetros foram medidos nos seguintes períodos: baseline, 90 dias e 180 dias após o procedimento cirúrgico. Nenhuma diferença estatisticamente significante foi observada entre os grupos em relação à redução da retração gengival com 6 meses de acompanhamento, embora tenha sido encontrada maior porcentagem de cobertura radicular no grupo RSPC+EMD (91%), quando comparado ao RSPC (87%) (p>0,05). Cobertura radicular completa foi obtida em 60% dos sítios no RSPC enquanto no grupo RSPC+EMD foi observada em 66,67% dos sítios. Dentro dos limites do presente estudo pôde-se concluir que o RSPC, associado ou não a EMD, levou a redução da recessão gengival, sem diferença estatística entre os grupos, após 6 meses de acompanhamento pós-operatório / Abstract: The aim of this study was to evaluate clinically the use of the Semilunar Coronally Positioned Flap (SCPF) for the treatment of gingival recessions, with or without Enamel Matrix Derivative (EMD). Thirty patients were selected, randomized and allocated in two groups: test (SCPF + EMD) and control (SCPF alone). To attend the study, subjects should present buccal Miller class I gingival recessions with height greater than or equal to 2.0 mm and less than to 4.0 mm in maxillary canines or premolars. Clinical parameters evaluated: gingival recession height (GRH), gingival recession width (GRW), clinical attachment level (CAL), probing depth (PD), height (HKT) and thickness (TKT) of keratinized tissue and papillas height (HP) and width (LP), as well as plaque and gingival index. These data were collected at baseline, 90 days and 180 days after surgery. No statistically significant difference was observed between the groups regarding the reduction of gingival recession after 6 months of follow-up, although a higher percentage of root coverage was found in SCPF + EMD group (91%), when compared to the SCPF (87%) (p> 0.05). Complete root coverage was observed in 60% of the sites of the control group (SCPF alone) and in 66,67% of the sites of the test group (SCPF+EMD). Within the limits of this study it was concluded that SCPF, associated or not with EMD may provide a reduction in gingival recession, with no statistical difference between groups / Mestrado / Periodontia / Mestra em Clínica Odontológica
19

Regeneração tecidual guiada: estudo da biocompatibilidade in vitro da membrana do compósito de poli(vinilideno-trifluoretileno)/titanato de bário / Guided tissue regeneration: in vitro biocompatibility of the membrane of poly(vinylidene-trifluoroethylene)/barium titanate composite

Teixeira, Lucas Novaes 13 April 2009 (has links)
O princípio da regeneração tecidual guiada (RTG) baseia-se na utilização de membranas biocompatíveis com a finalidade de impedir a migração dos tecidos conjuntivo e epitelial para a ferida, permitindo que células do ligamento periodontal repovoem a superfície radicular e regenerem o aparato de inserção do dente. A RTG tem sido utilizada em diversas situações clínicas para facilitar o reparo de defeitos ósseos e periodontais, sendo as membranas de politetrafluoretileno expandido (e-PTFE) as mais utilizadas. O objetivo deste estudo foi avaliar a biocompatibilidade in vitro de uma nova membrana do compósito de poli(vinilideno-trifluoretileno)/titanato de bário (P(VDF-TrFE)/BT). Para isso, osteoblastos, fibroblastos e queratinócitos, células com as quais a membrana entrará em contato durante o processo de RTG, foram cultivados sobre membranas de P(VDF-TrFE)/BT e PTFE (controle). Os seguintes parâmetros foram avaliados: 1) adesão celular por contagem em hemocitômetro; 2) proliferação celular por MTT e 3) adesão e morfologia celular por fluorescência, para as linhagens osteoblástica, fibroblástica e de queratinócitos; 1) medida do conteúdo de proteína total; 2) medida da atividade de fosfatase alcalina (ALP) e 3) formação de matriz mineralizada, para as linhagens osteoblástica e fibroblástica; 1) imunolocalização de ALP por fluorescência; 2) detecção histoquímica in situ da atividade de ALP e 3) expressão dos genes Runx2, Colágeno I (COL I), Ostepontina (OPN), ALP, Sialoproteína óssea (BSP), Osteocalcina (OC), Bax, Bcl-2 e Survivina (SUR) por PCR em tempo real, para a linhagem osteoblástica; 1) expressão dos genes Periostin (PRT), Periodontal Ligament Specific 17 (PDLs17), Calcium-binding protein (S100A4), Fibromodulina (FBM), Bax, Bcl-2 e SUR por PCR em tempo real, para a linhagem fibroblástica e 1) expressão dos genes Involucrina (IVL), Queratina 1 (QRT-1), Queratina 10 (QRT-10), Queratina 14 (QRT-14), Bax, Bcl-2 e SUR por PCR em tempo real, para a linhagem de queratinócitos. Os dados quantitativos foram submetidos ao teste estatístico Mann-Whitney (nível de significância: 5%). A adesão de células osteoblásticas foi semelhante entre P(VDF-TrFE)/BT e PTFE em 30 min, 2 e 4 h (p>0,05). A proliferação de células osteoblásticas foi maior em culturas crescidas sobre o P(VDF-TrFE)/BT em 1, 7 e 10 dias (p<0,05). A epifluorescência indicou que as células osteoblásticas estavam aderidas e mais espraiadas sobre o P(VDF-TrFE)/BT em 30 min, 4 e 24 h. A imunofluorescência revelou presença de ALP apenas em culturas crescidas sobre o P(VDF-TrFE)/BT em 7 e 14 dias. O conteúdo de proteína total foi semelhante entre as duas membranas em 10 dias (p>0,05) e maior sobre o P(VDF-TrFE)/BT em 7 e 14 dias (p<0,05). Não houve diferença estatisticamente significante para atividade de ALP em 7 dias (p>0,05), entretanto em 10 e 14 dias (p<0,05) a atividade de ALP foi maior em culturas sobre o P(VDFTrFE)/ BT. A detecção histoquímica in situ revelou atividade de ALP apenas em culturas crescidas sobre o P(VDF-TrFE)/BT, tanto aos 7 quanto aos 14 dias. A formação de matriz mineralizada ocorreu apenas em culturas crescidas sobre o P(VDF-TrFE)/BT. A expressão dos genes Runx2, COL I, OPN, ALP, BSP, OC, Bax e SUR foi maior em células cultivadas sobre o P(VDF-TrFE)/BT em 7 e 14 dias (p<0,05). Não houve expressão de Bcl-2 em culturas sobre as duas membranas. A adesão de células fibroblásticas foi semelhante entre P(VDFTrFE)/ BT e PTFE em 30 min (p>0,05) e maior sobre o P(VDF-TrFE)/BT em 2 e 4 h (p<0,05). A proliferação de células fibroblásticas foi estatisticamente semelhante entre as duas membranas em 3 dias (p>0,05) e maior em culturas crescidas sobre o P(VDF-TrFE)/BT em 1 e 7 dias (p<0,05). Os ensaios de fluorescência direta revelaram que as células fibroblásticas estavam aderidas sobre as duas membranas, porém em estágios mais avançados de espraiamento sobre o P(VDF-TrFE)/BT em 30 min, 2 e 4 h. O conteúdo de proteína total foi maior sobre o P(VDF-TrFE)/BT em 10, 14 e 21 dias (p<0,05). Não se observou atividade de ALP em culturas fibroblásticas sobre as membranas de P(VDF-TrFE)/BT e PTFE aos 7 dias. Contudo, em 14 dias (p>0,05) a atividade de ALP foi semelhante entre as duas membranas e em 21 dias (p<0,05) foi estatisticamente significante em culturas crescidas sobre o P(VDF-TrFE)/BT. Aos 21 dias não se notou formação de matriz mineralizada em ambas as membranas. A expressão dos genes PRT, PDLs17, S100A4, FBM, Bax e SUR foi maior em culturas sobre o P(VDF-TrFE)/BT em 7 e 14 dias (p<0,05). A expressão de Bcl-2 foi maior em células fibroblásticas cultivadas sobre o PTFE em 7 e 14 dias (p<0,05). A adesão de queratinócitos foi semelhante entre P(VDF-TrFE)/BT e PTFE em 30 min, 2 e 4 h (p>0,05). A proliferação de queratinócitos foi estatisticamente semelhante entre as duas membranas em 4, 7, 10 e 14 dias (p>0,05) e maior sobre culturas crescidas sobre P(VDF-TrFE)/BT em 1, 17 e 21 dias (p<0,05). Por fluorescência direta notou-se que células cultivadas sobre ambas as membranas exibiam morfologia predominantemente arredondada em 30 min, 4 e 24 h. A expressão do gene IVL foi semelhante em culturas crescidas sobre as duas membranas em 7 dias (p>0,05) e maior sobre o P(VDF-TrFE)/BT em 14 dias (p<0,05). Os genes QRT-1, QRT -10 e QRT -14, Bax e SUR estavam mais expressos em culturas sobre o P(VDF-TrFE)/BT em 7 e 14 dias (p<0,05). A expressão de Bcl-2 foi maior em queratinócitos crescidos sobre o PTFE em 7 dias (p<0,05) e semelhante entre as duas membranas em 14 dias (p>0,05). Por favorecer eventos relacionados ao desenvolvimento tecidual, como a adesão, proliferação e diferenciação celular, a membrana de P(VDF-TrFE)/BT pode representar uma boa alternativa ao PTFE para procedimentos de RTG. / The principle of guided tissue regeneration (GTR) is based on the use of physical barrier to isolate periodontal defects of the gingival connective and epithelial tissues so that bone, periodontal ligament, and cementum can be regenerated from their own cells. RTG procedure has been used in many clinical situations to promote bone and periodontal regeneration. Membranes of expanded polytetrafluoroethylene (e-PTFE) are the most commonly used material for GTR. However, several membranes have been tested to be applied in GTR. The purpose of this study was to evaluate the in vitro biocompatibility of the membrane of poly(vinylidene-trifluoroethylene/barium titanate (P(VDF-TrFE)/BT) composite. For that, osteoblasts, fibroblasts and keratinocytes, cells that will interact with the membrane during RTG, were culture P(VDF-TrFE)/BT and PTFE (control) membranes for up to 21 days. The following parameters were evaluated: 1) cell adhesion by counting in hemocytometer, 2) cell proliferation and 3) cell morphology by fluorescent labeling, for osteoblastic, fibroblastic and keratinocyte lineages; 1) total protein content; 2) alkaline phosphatase (ALP) activity and 3) mineralized bone-like nodule formation, for osteblastic and fibroblastic lineages; 1) immunolocalization of ALP by fluorescent labeling; 2) histochemistry detection in situ of ALP activity and 3) gene expression of Runx2, Collagen I (COL I), Ostepontin (OPN), ALP, Bone Sialoprotein (BSP), Osteocalcin (OC), Bax, Bcl-2 and Survivin (SUR) by real-time PCR, for osteoblastic lineage; 1) gene expression of Periostin (PRT), Periodontal ligament specific (PDLs17), Calcium-binding protein (S100A4), Fibromodulin (FBM), Bax, Bcl-2 and SUR by real-time PCR, for fibroblastic lineage; 1) gene expression of Involucrin (IVL), Keratin-1 (QRT-1), Keratin-10 (QRT-10), Keratin-14 (QRT- 14), Bax, Bcl-2 and SUR days by real-time PCR, for keratinocyte lineage. Data were submitted to Mann-Whitney test (level of significance: 5%). The adhesion of osteoblastic cells was similar between P(VDF-TrFE)/BT and PTFE at 30 min, 2 and 4 h (p>0.05). Cell proliferation was higher in ostegenic cultures grown on P(VDF-TrFE)/BT at 1, 7 and 10 days (p<0.05). Epifluorescence showed that osteoblastic cells grown on P(VDF-TrFE)/BT were more adhered and spread compared to PTFE at 30 min, 4 and 24 h. Immunofluorescence revealed the presence of ALP only in osteogenic cultures grown on P(VDF-TrFE)/BT at 7 and 14 days. Total protein content was similar between the membranes at 10 days (p>0.05) and higher on the P(VDF-TrFE)/BT at 7 and 14 days (p<0.05). There was no differences in ALP activity at 7 days (p>0.05). However, ALP activity was higher in osteogenic cultures on the P(VDF-TrFE)/BT at 10 and 14 days (p<0.05). The histochemistry reveals that only ostegenic cultures grown on P(VDF-TrFE)/BT had ALP activity in situ at 7 and 14 days. Bone-like nodule formation occurred only in cultures on the P(VDF-TrFE)/BT at 21 days. Gene expression of Runx2, COL I, OPN, ALP, BSP, OC, Bax and SUR was higher in cultures grown on P(VDF-TrFE)/BT at 7 and 14 days (p<0.05). There was no expression of Bcl-2 in cultures on both membranes. The adhesion of fibroblastic cells was similar between P(VDFTrFE)/ BT and PTFE at 30 min (p>0.05) and greater in fibroblastic cultures on P(VDFTrFE)/ BT at 2 and 4 h (p<0.05). Cell proliferation was similar in fibroblastic cultures grown on both membranes at 3 days (p>0.05) and higher in cultures on P(VDF-TrFE)/BT at 1 and 7 days (p<0.05). Epifluorescence showed that fibroblastic cells grown on P(VDF-TrFE)/BT were more adhered and more spread compared to PTFE at 30 min, 4 and 24 h. Total protein content was greater on P(VDF-TrFE)/BT at 10, 14 and 21 days (p<0.05). There was no ALP activity in fibroblastic cultures grown on both membranes at 7 days. The ALP activity was similar between P(VDF-TrFE)/BT and PTFE at 14 day (p>0.05) and higher on P(VDFTrFE)/ BT at 21 days (p<0.05). Bone-like nodule formation was not observed in fibroblastic cultures on both membranes at 21 days. Gene expression of PRT, PDLs17, S100A4, FBM, Bax and SUR was higher in cultures on the P(VDF-TrFE)/BT at 7 and 14 days (p<0.05). Bcl- 2 expression was higher in fibroblastic cultures on the PTFE at 7 and 14 days (p<0.05). Keratinocyte adhesion was similar for P(VDF-TrFE)/BT and PTFE at 30 min, 2 and 4 h (p>0.05). Keratinocyte proliferation was statistically similar on both membranes at 4, 7, 10 and 14 days (p>0.05) and higher in cultures grown on P(VDF-TrFE)/BT at 1, 17 and 21 days (p<0.05). Keratinocytes displayed a round morphology and was not observed any evidence of cell spreading at 30 min, 4 and 24 h. The gene expression of IVL was similar in cultures grown on P(VDF-TrFE)/BT and PTFE at 7 days (p>0.05) and higher on the P(VDF-TrFE)/BT at 14 days (p<0.05). Genes expression of QRT-1, QRT-10, QRT-14, Bax and SUR was greater in keratinocytes grown on P(VDF-TrFE)/BT at 7 and 14 days (p<0.05). Bcl-2 expression was higher in keratinocytes cultured on PTFE at 7 days (p<0.05) and similar on both membranes at 14 days (p>0.05). Our study indicates that P(VDF-TrFE)/BT membrane promote events related to tissue development/regeneration, such as cell adhesion, proliferation and differentiation. Thus, the membrane of P(VDF-TrFE)/BT could be used as an advantageous alternative to PTFE in GTR procedures.
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Análise histológica da utilização da matriz dérmica acelular e da matriz de pericárdio bovino, associados ao retalho reposicionado coronariamente, no tratamento de deiscências ósseas criadas cirurgicamente em cães /

Oliveira, Cristiane Aparecida de. January 2005 (has links)
Orientador: Rosemary Adriana Chiérici Marcantonio / Banca: Joni Augusto Cirelli / Banca: Elizabeth Pimentel Rosetti / Banca: Washington Rodrigues Camargo / Banca: Giuseppe Alexandre Romito / Resumo: O propósito deste estudo foi avaliar histológica e histometricamente o resultado da utilização das matrizes de colágeno de Pericárdio Bovino (MPB) e Dérmica Acelular (MAD) no tratamento de deiscências ósseas criadas cirurgicamente em cães. Foram criados defeitos periodontais do tipo deiscência óssea na superfície vestibular dos 2os, 3os e 4os pré-molares inferiores de seis cães. Estes dentes foram divididos em 3 grupos: grupo I: MAD; grupo II: controle e grupo III: MPB, ambos com reposição coronária do retalho. Após 70 dias os animais foram sacrificados, os dentes retirados em bloco e processados histologicamente. Realizou-se análise histológica descritiva e histométrica, medindo-se a extensão do tecido epitelial, neoformação óssea e cementária e nível gengival para os grupos I, II e III. Os resultados demonstraram valores estatisticamente iguais para as medianas (em mm) dos valores de epitélio: 1,49, 1,91 e 1,82; cemento: 3,18, 3,09 e 3,31 respectivamente para os grupos I, II e III. Foi encontrada diferença estatisticamente significante em relação à neoformação óssea, com medianas (em mm) de 1,23, 1,82 e 1,62, respectivamente para os grupos I, II e III. Foi observado escasso infiltrado inflamatório. Com isso, pudemos concluir que as matrizes de MPB e MAD são materiais que permitem a reparação dos tecidos periodontais. / Abstract: The goal of this investigation was to compare, histologically and histometrically, the healing process of dehiscence-type defects treated by acellular dermal matrix (AD) and bovine pericardium matrix (PB). Six mongrel dogs were used. Buccal osseous deiscences were surgically created on mesial roots of the mandibular second, third and fourth premolars. The defects were randomly assigned to one of the treatments: AD, control and PB. After 70 days of healing, the dogs were sacrificed and the blocks were processed. The histometric parameters evaluated included: gingival level, epithelial length, new cementum and new bone. No statistically significant differences were found between PB, AD and control groups for epithelial length and new cementum parameters (p<0,05). Statistically significant differences were found between PB, AD and control groups for new bone (minor for AD). The presence of a slight inflammation was observed. Withim the limits of this study, it can be concluded that PB and AD showed good biocompatibility, but did not bring a complete periodontal tissue regeneration. / Doutor

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