RESUMO
BACKGROUND: The aim of this study was to evaluate the incidence of preloading crestal bone loss (PLCBL) and to identify the patient-related and implant-related factors associated with PLCBL. METHODS: This retrospective cohort examined the dental records of patients who received at least one dental implant. PLCBL was defined as a reduction ⩾0.5 mm and severe PLCBL (primary variable) as a reduction ⩾1.5 mm in mesial and/or distal bone level, measured from the day of implant placement to uncovering or abutment installation/crown delivery. The incidence of PLCBL and patient and implant variables were recorded. Bivariate analysis and binary logistic regression identified factors associated with PLCBL ⩾0.5 mm and ⩾1.5 mm. RESULTS: A total of 746 dental implants placed in 361 patients from January 2011 to July 2021 was included in the analyses. Of the implants assessed, 24.4% (n = 182) exhibited PLCBL ⩾ 0.5 mm and 10.5% (n = 78) presented severe PLCBL (i.e., ⩾1.5 mm). Males (odds ratio [OR] = 1.85, 95% confidence interval [CI] = 1.11-3.07), patients with diabetes (OR = 3.33, 95% CI = 1.73-6.42), and those allergic to penicillin (OR = 3.13, 95% CI = 1.57-6.22) were more likely to experience severe PLCBL (p < 0.05). Implants placed in the anterior area (OR = 2.08, 95% CI = 1.16-3.73), with bone-level platform-abutment connection (OR = 4.73, 95% CI = 1.94-11.49) and inserted supracrestally (OR = 3.77, 95% CI = 1.84-7.72), presented a greater risk of developing severe PLCBL (p < 0.05). Implants placed in a previously grafted area presented a lower likelihood of developing severe PLCBL (OR = 0.489, 95% CI = 0.28-0.84). CONCLUSION: The incidence of PLCBL ⩾ 0.5 mm and ⩾1.5 mm was 24.4% and 10.5%, respectively. Male sex, diabetes, allergy to penicillin, anterior location, bone-level platform-abutment connection, and supracrestal implant placement are potential risk factors for severe PLCBL. A previously grafted area is a potential protective factor.
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Perda do Osso Alveolar , Implantes Dentários , Humanos , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Perda do Osso Alveolar/epidemiologia , Incidência , Idoso , Adulto , Fatores de Risco , Implantação Dentária Endóssea/métodos , Fatores Sexuais , Idoso de 80 Anos ou maisRESUMO
OBJECTIVE: Maintenance of adequate interproximal tissue height between an implant and a natural tooth or between adjacent implants represents an esthetic challenge in implant dentistry. The aim of this case report is to describe a modified technique referred to as the beyond the gap filling (BGF) approach designed to improve the horizontal and vertical components of the facial aspect and particularly the height of interproximal bone peaks around immediately placed implants into fresh extraction sockets. CLINICAL CONSIDERATIONS: Four patients (five teeth) requiring anterior tooth extraction were treated with the BGF approach that included: (a) minimally traumatic tooth extraction; (b) immediate implant placement without flap elevation; (c) installation of a narrow profile healing abutment to protect the implant during grafting; (d) grafting with a construct with 90% bovine bone granules and 10% porcine collagen packed coronally to the facial and interproximal bone walls above the level of the bone crest; and (e) delivery of an immediate restoration. CONCLUSIONS: The current report suggests that the level/height of the interproximal bone crests between an implant and a natural tooth or between two adjacent implants can be improved by the BGF approach and, consequently, papilla height can be maintained in cases with a high risk of papilla height collapse and, consequently, esthetic outcomes can be maximized. CLINICAL SIGNIFICANCE: The BGF is a simple technique to be used by clinicians to prevent significant papilla collapse in anterior immediate implants and consequently achieve maximum esthetic outcomes in implant dentistry.
Assuntos
Implantes Dentários para Um Único Dente , Carga Imediata em Implante Dentário , Implantação Dentária Endóssea/métodos , Estética Dentária , Humanos , Carga Imediata em Implante Dentário/métodos , Maxila/cirurgia , Extração Dentária , Alvéolo Dental/cirurgia , Resultado do TratamentoRESUMO
PURPOSE: To evaluate the local effect of simvastatin (SVT) combined with deproteinized bovine bone (DBB) with hydroxyapatite/ß-tricalcium phosphate biphasic ceramics (HA/TCP) and with collagen sponge (CS) on bone repair in critical size defects (CSDs) in rat calvaria. METHODS: Forty-two 5-mm diameter CSDs were made bilaterally in the calvaria of 18 rats. The animals were allocated according to the type of biomaterial and associations used to fill the CSD. After 8 weeks, the animals were euthanized, and their calvaria were evaluated for repaired tissue composition using histologic and histometric analyses. RESULTS: In the histometric analysis, the use of SVT showed to increase bone formation in the CSDs when combined with all the bone substitutes tested in this study (p<0.05). Greater bone formation was observed in the groups with SVT compared to the groups without SVT. CONCLUSIONS: The use of SVT without the need for a vehicle and combined with a commercially available biomaterial may be a cheaper way to potentiate the formation of bone tissue without the need to produce new biomaterials. Therefore, SVT combined with DBB induced significantly greater new bone formation than did the other treatments.
Assuntos
Materiais Biocompatíveis/farmacologia , Substitutos Ósseos/farmacologia , Colágeno/farmacologia , Osteogênese/efeitos dos fármacos , Sinvastatina/farmacologia , Crânio/efeitos dos fármacos , Animais , Anticolesterolemiantes/farmacologia , Regeneração Óssea/efeitos dos fármacos , Transplante Ósseo/métodos , Bovinos , Modelos Animais de Doenças , Feminino , Ratos , Ratos Wistar , Crânio/cirurgiaRESUMO
Purpose To evaluate the local effect of simvastatin (SVT) combined with deproteinized bovine bone (DBB) with hydroxyapatite/β-tricalcium phosphate biphasic ceramics (HA/TCP) and with collagen sponge (CS) on bone repair in critical size defects (CSDs) in rat calvaria. Methods Forty-two 5-mm diameter CSDs were made bilaterally in the calvaria of 18 rats. The animals were allocated according to the type of biomaterial and associations used to fill the CSD. After 8 weeks, the animals were euthanized, and their calvaria were evaluated for repaired tissue composition using histologic and histometric analyses. Results In the histometric analysis, the use of SVT showed to increase bone formation in the CSDs when combined with all the bone substitutes tested in this study (p<0.05). Greater bone formation was observed in the groups with SVT compared to the groups without SVT. Conclusions The use of SVT without the need for a vehicle and combined with a commercially available biomaterial may be a cheaper way to potentiate the formation of bone tissue without the need to produce new biomaterials. Therefore, SVT combined with DBB induced significantly greater new bone formation than did the other treatments.(AU)
Assuntos
Animais , Ratos , Sinvastatina/administração & dosagem , Sinvastatina/uso terapêutico , Materiais Biocompatíveis , Colágeno , Regeneração ÓsseaRESUMO
Abstract Purpose To evaluate the local effect of simvastatin (SVT) combined with deproteinized bovine bone (DBB) with hydroxyapatite/β-tricalcium phosphate biphasic ceramics (HA/TCP) and with collagen sponge (CS) on bone repair in critical size defects (CSDs) in rat calvaria. Methods Forty-two 5-mm diameter CSDs were made bilaterally in the calvaria of 18 rats. The animals were allocated according to the type of biomaterial and associations used to fill the CSD. After 8 weeks, the animals were euthanized, and their calvaria were evaluated for repaired tissue composition using histologic and histometric analyses. Results In the histometric analysis, the use of SVT showed to increase bone formation in the CSDs when combined with all the bone substitutes tested in this study (p<0.05). Greater bone formation was observed in the groups with SVT compared to the groups without SVT. Conclusions The use of SVT without the need for a vehicle and combined with a commercially available biomaterial may be a cheaper way to potentiate the formation of bone tissue without the need to produce new biomaterials. Therefore, SVT combined with DBB induced significantly greater new bone formation than did the other treatments.
Assuntos
Humanos , Animais , Feminino , Bovinos , Ratos , Osteogênese/efeitos dos fármacos , Crânio/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Colágeno/farmacologia , Substitutos Ósseos/farmacologia , Sinvastatina/farmacologia , Crânio/cirurgia , Regeneração Óssea/efeitos dos fármacos , Transplante Ósseo/métodos , Ratos Wistar , Modelos Animais de Doenças , Anticolesterolemiantes/farmacologiaRESUMO
PURPOSE: To investigate the effects of locally applied simvastatin plus biphasic calcium phosphate (BoneCeramic(r)) or collagen sponge on bone formation in critical-sized bone defects. METHODS: Thirty defects of 5mm in diameter were created bilaterally with a trephine bur in the calvariae of fifteen Wistar rats. The defects were divided into five groups: group 1 - control, no treatment; group 2 (BoneCeramic(r)); group 3 (BoneCeramic(r) + 0.1mg simvastatin); group 4 (collagen sponge); and group 5 (collagen sponge + 0.1mg simvastatin). After eight weeks the animals were euthanized and their calvariae were histologically processed. Hematoxylin and eosin-stained sections were subjected to histological and histomorphometrical analyses. The area of newly formed bone was calculated and compared between groups. RESULTS: The greater amount of a bone-like tissue was formed around the carrier in group 3 (BoneCeramic(r) + 0.1mg simvastatin) followed by group 2 (BoneCeramic(r)), and almost no bone was formed in the other groups. Group 3 was significantly different compared to group 2, and both groups were significantly different compared to the other groups. CONCLUSION: Simvastatin combined with BoneCeramic(r) induced significantly greater amounts of newly formed bone and has great potential for the healing of bone defects.
Assuntos
Anticolesterolemiantes/farmacologia , Hidroxiapatitas/farmacologia , Osteogênese/efeitos dos fármacos , Sinvastatina/farmacologia , Crânio/efeitos dos fármacos , Animais , Matriz Óssea/ultraestrutura , Colágeno/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Ratos Wistar , Crânio/lesões , Crânio/patologia , CicatrizaçãoRESUMO
ABSTRACT PURPOSE: To investigate the effects of locally applied simvastatin plus biphasic calcium phosphate (BoneCeramic(r)) or collagen sponge on bone formation in critical-sized bone defects. METHODS: Thirty defects of 5mm in diameter were created bilaterally with a trephine bur in the calvariae of fifteen Wistar rats. The defects were divided into five groups: group 1 - control, no treatment; group 2 (BoneCeramic(r)); group 3 (BoneCeramic(r) + 0.1mg simvastatin); group 4 (collagen sponge); and group 5 (collagen sponge + 0.1mg simvastatin). After eight weeks the animals were euthanized and their calvariae were histologically processed. Hematoxylin and eosin-stained sections were subjected to histological and histomorphometrical analyses. The area of newly formed bone was calculated and compared between groups. RESULTS: The greater amount of a bone-like tissue was formed around the carrier in group 3 (BoneCeramic(r) + 0.1mg simvastatin) followed by group 2 (BoneCeramic(r)), and almost no bone was formed in the other groups. Group 3 was significantly different compared to group 2, and both groups were significantly different compared to the other groups. CONCLUSION: Simvastatin combined with BoneCeramic(r) induced significantly greater amounts of newly formed bone and has great potential for the healing of bone defects.
Assuntos
Animais , Feminino , Osteogênese/efeitos dos fármacos , Crânio/efeitos dos fármacos , Sinvastatina/farmacologia , Hidroxiapatitas/farmacologia , Anticolesterolemiantes/farmacologia , Crânio/lesões , Crânio/patologia , Cicatrização , Matriz Óssea/ultraestrutura , Colágeno/efeitos dos fármacos , Ratos Wistar , Modelos Animais de DoençasRESUMO
PURPOSE:To investigate the effects of locally applied simvastatin plus biphasic calcium phosphate (BoneCeramic(r)) or collagen sponge on bone formation in critical-sized bone defects.METHODS:Thirty defects of 5mm in diameter were created bilaterally with a trephine bur in the calvariae of fifteen Wistar rats. The defects were divided into five groups: group 1 - control, no treatment; group 2 (BoneCeramic(r)); group 3 (BoneCeramic(r) + 0.1mg simvastatin); group 4 (collagen sponge); and group 5 (collagen sponge + 0.1mg simvastatin). After eight weeks the animals were euthanized and their calvariae were histologically processed. Hematoxylin and eosin-stained sections were subjected to histological and histomorphometrical analyses. The area of newly formed bone was calculated and compared between groups.RESULTS:The greater amount of a bone-like tissue was formed around the carrier in group 3 (BoneCeramic(r) + 0.1mg simvastatin) followed by group 2 (BoneCeramic(r)), and almost no bone was formed in the other groups. Group 3 was significantly different compared to group 2, and both groups were significantly different compared to the other groups.CONCLUSION:Simvastatin combined with BoneCeramic(r) induced significantly greater amounts of newly formed bone and has great potential for the healing of bone defects.(AU)
Assuntos
Animais , Ratos , Sinvastatina/efeitos adversos , Sinvastatina/análise , Fosfatos de Cálcio/análise , Osteogênese , Crânio/lesões , Regeneração Óssea , Ratos WistarRESUMO
Dr. David L. Cochran é graduado pela University of Virginia e recebeu os títulos de DDS, MS e PhD em Bioquímica pela Medical College of Virginia. Especializou-se em Periodontia pela Harvard School of Dental Medicine, onde também recebeu um segundo título de mestre. Recentemente, o Dr. Cochran recebeu o título de Doctor HonorisCausa pela University of Bern, na Suíça. Atualmente, é professor e chefe do Departamento de Periodontia na Faculdade de Odontologia da University of Texas Health Science Center, na cidade de San Antonio, nos Estados Unidos. Antes de assumir o cargo em San Antonio, era diretor do programa de pós-graduação em Periodontia naMedical College of Virginia. Dr. Cochran é membro de muitas organizações profissionais de Odontologia e diplomado pelo American Board of Periodontology. Além disso, é membro do American College of Dentistry e do International College of Dentistry.Dr. Cochran publicou inúmeros artigos científicos e resumos sobre vários tópicos relacionados à Periodontia, Bioquímica e Implantodontia. Recebeu prêmios nacionais e internacionais por suas pesquisas, e é um pesquisador clínico e científico ativo financiado tanto pela NIH-NIDCR (National Institutes of Health / National Institute of Dental and Craniofacial Research) quanto pela indústria privada...
Dr. David L. Cochran is a graduate of the University of Virginia and received hisDDS., MS. and PhD degrees in Biochemistry from the Medical College of Virginia (MCV). He was trained in Periodontology at the Harvard School of Dental Medicine where he also obtained a second Masters degree. He recently received an Honorary Doctorate from the University of Bern in Switzerland. Dr. Cochran is currently Professor and Chairman of the Department of Periodontics at The University of Texas Health Science Center at San Antonio, Dental School. Prior to his appointmentat San Antonio, Dr. Cochran was Director of Postgraduate Periodontics atMCV. Dr. Cochran is a member of many professional dental organizations and isa Diplomate of the American Board of Periodontology. He is a fellow of the American College of Dentistry and the International College of Dentistry. Dr. Cochran has published numerous scientific articles and abstracts on various periodontal, biochemistry, and implant topics. He has received awards for his research work at both the national and international levels. Dr. Cochran is an active basic science and clinical researcher who has received funding from both the NIH-NIDCR andprivate industry...
Assuntos
Humanos , Masculino , Feminino , Implantes Dentários , OsseointegraçãoRESUMO
PURPOSE: To analyze the effects of simvastatin (SVT) in the locomotion, anxiety and memory of rats, as a reflection of the administration of a minimum dose capable of stimulating bone regeneration in defects in the calvariae. METHODS: Surgical procedures were performed in 15 female Wistar rats, 2-month old, to insert the grafting material regenerator (Bone-ceramic®) and/or SVT, followed by behavioural and cognitive assessments in the 7th, 30th and 60th days post surgery. RESULTS: The SVT locally applied with the goal of bone regeneration in defects created in rat calvariae does not interfere with locomotion, anxiety levels and/or memories of rats, except for the first week following surgery, when an anxiolytic effect was observed, as a result of a possible central action. CONCLUSION: Failure to provoke any response within 30 and 60 days post surgical procedures suggests that SVT may constitute a good choice in stimulating bone regeneration without affecting the long term neural functions.
Assuntos
Anticolesterolemiantes/administração & dosagem , Comportamento Animal/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Cognição/efeitos dos fármacos , Sinvastatina/administração & dosagem , Animais , Ansiedade/induzido quimicamente , Modelos Animais de Doenças , Feminino , Locomoção/efeitos dos fármacos , Memória/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Ratos Wistar , Crânio/efeitos dos fármacos , Crânio/cirurgia , Fatores de TempoRESUMO
To analyze the effects of simvastatin (SVT) in the locomotion, anxiety and memory of rats, as a reflection of the administration of a minimum dose capable of stimulating bone regeneration in defects in the calvariae. METHODS: Surgical procedures were performed in 15 female Wistar rats, 2-month old, to insert the grafting material regenerator (Bone-ceramic(r)) and/or SVT, followed by behavioural and cognitive assessments in the 7th, 30th and 60th days post surgery. RESULTS: The SVT locally applied with the goal of bone regeneration in defects created in rat calvariae does not interfere with locomotion, anxiety levels and/or memories of rats, except for the first week following surgery, when an anxiolytic effect was observed, as a result of a possible central action. CONCLUSION: Failure to provoke any response within 30 and 60 days post surgical procedures suggests that SVT may constitute a good choice in stimulating bone regeneration without affecting the long term neural functions.(AU)
Assuntos
Animais , Ratos , Sinvastatina , Regeneração Óssea/fisiologia , Cirurgia Geral , RatosRESUMO
To analyze the effects of simvastatin (SVT) in the locomotion, anxiety and memory of rats, as a reflection of the administration of a minimum dose capable of stimulating bone regeneration in defects in the calvariae. METHODS: Surgical procedures were performed in 15 female Wistar rats, 2-month old, to insert the grafting material regenerator (Bone-ceramic(r)) and/or SVT, followed by behavioural and cognitive assessments in the 7th, 30th and 60th days post surgery. RESULTS: The SVT locally applied with the goal of bone regeneration in defects created in rat calvariae does not interfere with locomotion, anxiety levels and/or memories of rats, except for the first week following surgery, when an anxiolytic effect was observed, as a result of a possible central action. CONCLUSION: Failure to provoke any response within 30 and 60 days post surgical procedures suggests that SVT may constitute a good choice in stimulating bone regeneration without affecting the long term neural functions.
Assuntos
Animais , Ratos , Cirurgia Geral , Regeneração Óssea/fisiologia , Sinvastatina , RatosRESUMO
As tendências atuais na terapia com implantes odontológicostêm incluído o uso de implantes com superfícies modificadasutilizando nanotecnologia. Ciência que permite a construçãode novos materiais e dispositivos pela manipulação de átomosindividuais e moléculas (escala menor do que 100nm). O objetivodeste trabalho foi avaliar o papel das modificações em escalananométrica de superfícies de implantes osseointegradospara melhorar o processo de osseointegração. Nanotecnologiaoferece a engenheiros e profissionais da área de biologia e saúdenovos meios para entender e otimizar funções e respostasespecíficas de células. As várias técnicas utilizadas para adicionarcaracterísticas nanométricas às superfícies de implantesosseointegrados são descritas neste trabalho. Vários trabalhostem apresentado os efeitos da nanotecnologia na modulaçãode etapas fundamentais do processo de osseointegração. Asvantagens e desvantagens da utilização da nanotecnologia nasuperfície de implantes também são discutidas nesse trabalho.Posteriormente, em uma série de experimentos in vitro e in vivo,foi possível avaliar o efeito específico destas modificações emdois diferentes modelos. Como efeitos observados da aplicaçãode nanoestruturas à superfície dos implantes osseointegradosfoi possível verificar-se uma melhor e mais rápida resposta deosseointegração destes materiais, atuando efetivamente na cascatade diferenciação de osteoblastos.
Current trends in clinical dental implant therapy include useof endosseous dental implant surfaces embellished with nanoscaletopographies. Nanotechnology deals with materials withat least one significant dimension less than 100nm. The goal ofthis study was to consider the role of nanoscale topographic modificationof titanium substrates for the purpose of improvingosseointegration. Nanotechnology offers engineers and biologistsnew ways of interacting with relevant biological processes.Moreover, nanotechnology has provided means of understandingand achieving cell specific functions. The various techniquesthat can impart nanoscale topographic features to titaniumendosseous implants are described. Existing data supportingthe role of nanotopography suggests that critical steps in osseointegrationcan be modulated by nanoscale modification ofthe implant surface. Important distinctions between nanoscaleand micron-scale modification of the implant surface are presentlyconsidered. The advantages and disadvantages of nanoscalemodification of the dental implant surface are discussed.Finally, available data concerning the current dental implantsurfaces that utilize nanotopography in clinical dentistry aredescribed. Nanoscale modification of titanium endosseous implantsurfaces can alter cellular and tissue responses that maybenefit osseointegration and dental implant therapy. In a seriesof in vitro and in vivo experiments it was possible to evaluatethe effect of this modifications in different study designs. Theadvantages of the use of nanocues added to the surface of theosseointegrated dental implants allowed to a better and fasterosseointegration response of these materials, by acting on thedifferentiation of the osteoblasts.
RESUMO
A correção cirúrgica do sorriso gengival decorrente de uma erupção passiva alterada é um procedimento comumente realizado em Periodontia. Uma das dificuldades desse procedimento é a obtenção de um arquitetura gengival harmoniosa bilateralmente, assim como a definição precisa dos contornos gengivais, os quais são importantes na estética do sorriso. Portanto, os reparos cirúrgicos são relativamente frequentes, o que é algo problemático tanto para o paciente como para o periodontista. O caso clínico aqui apresentado descreve um protocolo utilizado há vários anos pelo nosso grupo para a correção de sorrisos gengivais, o qual oferece previsibilidade, precisão e tem possibilitado resultados estáveis a longo prazo, sem a necessidade de reparos cirúrgicos.
Assuntos
Humanos , Feminino , Adolescente , Aumento da Coroa Clínica , Gengiva/cirurgia , Sorriso , Colo do Dente , Protocolos Clínicos , Estética Dentária , Procedimentos Cirúrgicos BucaisRESUMO
PURPOSE: The use of nanotechnology to enhance endosseous implant surfaces may improve the clinical control of interfacial osteoblast biology. This study investigated the influence of a nanostructure-coated implant surface on osteoblast differentiation and its effects on bone-to-implant contact (BIC) and removal torque values. MATERIALS AND METHODS: Titanium disks were machined (M) or machined and subsequently treated by acid etching (Ac) or by dipping in an aluminum oxide solution (Al2O3). Surfaces were characterized by scanning electron microscopy, atomic force microscopy, and x-ray microanalysis. For the in vitro experiment, rat mesenchymal stem cells (rMSCs) were grown in osteogenic supplements on the disk surfaces for 3 days. Real-time polymerase chain reaction (PCR) was used to measure mRNA levels of several gene products (bone sialoprotein, osteocalcin, osteopontin, and RUNX-2). For the in vivo experiment, titanium implants were placed in rat tibiae and harvested after 3 to 21 days for measurement of bone-specific mRNA levels by real-time PCR. Removal torque and BIC were measured 3 to 56 days after placement. RESULTS: Average height deviation (Sa, in nm) values for M, Ac, and Al2O3 implants were 86.5, 388.4, and 61.2, respectively. Nanostructured Al2O3 topographic features applied to machined implants promoted MSC commitment to the osteoblast phenotype. Greater bone-specific gene expression was observed in tissues adjacent to Al2O3 implants, and associated increases in BIC and torque removal were noted. CONCLUSION: Nanostructured alumina may directly influence cell behavior to enhance osseointegration.
Assuntos
Óxido de Alumínio/administração & dosagem , Materiais Revestidos Biocompatíveis/administração & dosagem , Implantes Dentários , Células-Tronco Mesenquimais/metabolismo , Nanoestruturas , Osseointegração/efeitos dos fármacos , Óxido de Alumínio/química , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Materiais Revestidos Biocompatíveis/química , Subunidade alfa 1 de Fator de Ligação ao Core/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Remoção de Dispositivo , Regulação da Expressão Gênica , Sialoproteína de Ligação à Integrina , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osseointegração/fisiologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteocalcina/efeitos dos fármacos , Osteocalcina/genética , Osteocalcina/metabolismo , Osteopontina/efeitos dos fármacos , Osteopontina/genética , Osteopontina/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Sialoglicoproteínas/efeitos dos fármacos , Sialoglicoproteínas/genética , Sialoglicoproteínas/metabolismo , Propriedades de Superfície , Tíbia/citologia , Tíbia/cirurgiaRESUMO
AIM: The aim of this study was to apply a novel method to obtain high-quality images by cone-beam computerized tomography (CBCT) that consistently allowed the determination of the dimensions of the palatal mucosa. MATERIALS AND METHODS: Thirty-one patients participated in this study. At the time of the CBCT scanning, the patients wore a plastic lip retractor and wooden spatulas to retract soft tissues away from the teeth and gingiva. The thickness of the palatal mucosa was obtained at forty different locations on each patient. RESULTS: Retraction of the lips and cheek allowed a clear observation and measurements of the thickness of the palatal masticatory mucosa. The average thickness of the palatal mucosa was 2.92 mm in the canine area, 3.11 mm at the first pre-molar, 3.28 mm at the second pre-molar, 2.89 mm at the first molar and 3.15 mm at the second molar. Statistical differences were observed at different ages and heights of measurements. CONCLUSIONS: A new non-invasive method to consistently obtain high-quality images of the palatal masticatory mucosa is described. Measurements of this mucosa could be obtained at different locations on the palate.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Mucosa Bucal/anatomia & histologia , Palato/anatomia & histologia , Radiografia Dentária Digital/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/diagnóstico por imagem , Palato/diagnóstico por imagem , Radiografia Dentária Digital/instrumentação , Valores de Referência , Adulto JovemRESUMO
This study investigated the influence of nanoscale implant surface features on osteoblast differentiation. Titanium disks (20.0 x 1.0 mm) with different nanoscale materials were prepared using sol-gel-derived coatings and characterized by scanning electron microscopy, atomic force microscopy and analyzed by X-ray Photoelectron Spectrometer. Human Mesenchymal Stem Cells (hMSCs) were cultured on the disks for 3-28 days. The levels of ALP, BSP, Runx2, OCN, OPG, and OSX mRNA and a panel of 76 genes related to osteogenesis were evaluated. Topographical and chemical evaluation confirmed nanoscale features present on the coated surfaces only. Bone-specific mRNAs were increased on surfaces with superimposed nanoscale features compared to Machined (M) and Acid etched (Ac). At day 14, OSX mRNA levels were increased by 2-, 3.5-, 4- and 3-fold for Anatase (An), Rutile (Ru), Alumina (Al), and Zirconia (Zr), respectively. OSX expression levels for M and Ac approximated baseline levels. At days 14 and 28 the BSP relative mRNA expression was significantly up-regulated for all surfaces with nanoscale coated features (up to 45-fold increase for Al). The PCR array showed an up-regulation on Al coated implants when compared to M. An improved response of cells adhered to nanostructured-coated implant surfaces was represented by increased OSX and BSP expressions. Furthermore, nanostructured surfaces produced using aluminum oxide significantly enhanced the hMSC gene expression representative of osteoblast differentiation. Nanoscale features on Ti implant substrates may improve the osseointegration response by altering adherent cell response.
Assuntos
Expressão Gênica , Nanoestruturas , Osteoblastos/fisiologia , Próteses e Implantes , Óxido de Alumínio/química , Animais , Diferenciação Celular/fisiologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/metabolismo , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Osseointegração/fisiologia , Osteoblastos/citologia , Propriedades de Superfície , Titânio/química , Zircônio/químicaRESUMO
O objetivo deste estudo foi avaliar uma superfície de implante dentário compatível biologicamente e que aumente a resposta celular de osteoblastos de maneira a estimular o processo de diferenciação do tecido ósseo. Neste estudo foram utilizados discos de titânio comercialmente puro (cpTi) grau IV (6,0 mm x 1,0 mm) divididos em três grupos. Estes discos foram somente usinados (grupo U) ou usinados e subsequentemente tratados com ataque ácido (grupo Ac) ou usinado, jateamento e ataque ácido (grupo J/Ac). Células mesenquimais humanas indiferenciadas foram cultivadas sobre os discos e diferenciadas em osteoblastos. Os níveis de expressão de genes relacionados à diferenciação do tecido ósseo (Fostatase Alcalina-ALP; Sialoproteína Óssea-BSP; e Runx2) foram avaliados após sete e 21 dias através de PCR-tempo real (o gene GAPDH foi utilizado como controle endógeno). Após 35 dias avaliou-se a formação de nódulos de mineralização corados com Alizarin Red S. Observou-se um aumento relativo nos níveis de expressão dos genes ALP, BSP e Runx2 para a superfície com J/Ac quando comparada com as superfícies U e Ac. Após 21 dias a expressão de ALP estava 80 vezes maior na superfície J/Ac e o aumento no nível de BSP foi de 25 vezes. Após 35 dias a área mineralizada foi de 18%, 71% e 80%, para as superfícies U, Ac e J/Ac, respectivamente. Estes resultados sugerem que o jateamento da superfície previamente ao ataque ácido permitiu um maior nível de expressão de genes relacionados à cascata de diferenciação do tecido ósseo e formação de nódulos de mineralização in vitro, podendo levar a uma maior e melhor resposta de osseointegração destas superfícies.
Novel implant surfaces have been developed to improve/accelerate the osseointegration process. The mechanism by which implant surface improves osteoblast response at endosseous titanium implants is not fully understood. One of the mechanisms is related to induction of expression of bone-tissue specific genes inducing cells to differentiate into osteoblasts. The aim of this study was to evaluate a biologically compatible implant surface that can improve osteoblast responses and leads to a faster osseointegration. Commercially pure grade IV titanium disks (6.0x1.0mm) were machined (U) or machined acid etching (Ac) or sandblasted/acid etching (J/Ac), and divided into three groups. Human Mesenchymal Stem Cells were plated onto the disks and differentiated into osteoblasts. The expression levels of osteoblast-specific genes were evaluated by Real Time PCR to measure the mRNA levels of alkaline phosphatase (ALP), bone sialoprotein (BSP), and Runx2 after 7 and 21 days. The housekeeping gene GAPDH was used as a control. At 35 days, mineralization nodules were evaluated by Alizarin Red S staining. After 21 days, the expression levels of ALP for J/Ac and BSP were upregulated 80-fold and 25-fold, respectively. After 35 days, the mineralized area U, Ac and J/Ac was 18%, 71%, and 80%, for, respectively. The results demonstrated that a sandblasted/acid etched surface can affect adherent cell-bone specific gene expression, leading to a higher expression of osteoblast-specific genes and an increased in vitro mineralization response.
Assuntos
Condicionamento Ácido do Dente , Abrasão Dental por Ar , Fosfatase Alcalina , Expressão Gênica , Implantes Dentários , Células-Tronco Mesenquimais , Osteoblastos , SialoglicoproteínasRESUMO
Objetivo: Verificar se existe variação da espessura corneana com a midríase após instilação de Tropicamida a 1 por cento. Local: Clínica de Olhos da Santa Casa de Misericórdia de Belo Horizonte. Métodos: Medidas paquimétricas foram realizadas em 70 olhos de 36 pacientes antes e 30 minutos após a midríase com Tropicamida a 1 por cento. Em cada olho foram realizadas três medidas centrais utilizando o paquímetro ultra-sônico TopconP. G. H. Resultados: A média da espessura corneana encontrada antes da mídriase foi de 527,50mm no olho direito (OD) e 531,15mm no olho esquerdo (OE); após a midríase, 531,57mm e 531,71mm, respectivamente. Não houve diferenças estatisticamente significativas entre a espessura corneana antes a após a mídriase (p+0,083). Conclusão: A mídriase por tropicamida a 1por cento não interfere, estatisticamente, na medida paquimétrica corneana.