Uso de ligas metálicas básicas em próteses sobre implantes: análise da adaptação marginal

The original protocol for implant prosthesis recommends the use of a gold framework for acrylic and ceramic prosthesis. However, due to its high cost, the use of alternative alloys is desired. This study compares the marginal accuracy of pre-made cylinders versus plastic cylinders cast with two different base metal casting alloys. Five samples each of (1) plastic cylinder cast in cobalt-chromium alloy, (2) plastic cylinder cast in nickel-chromium alloy, and (3) silver-palladium pre-made cylinder (control) were examined for marginal accuracy according to: (A) vertical gap; (B) horizontal gap and (C) horizontal gap depth at the abutment/cylinder interface. Data were submitted to statistical analysis (ANOVA and Student-Newman Keuls, pO protocolo para prótese sobre implantes recomenda o uso de uma infra-estrutura em ouro para próteses metalo-plásticas e metalo-cerâmicas. No entanto, devido ao seu alto custo, o uso de ligas alternativas é desejado. OBJETIVO: Este estudo compara a adaptação marginal de cilindros protéticos pré-fabricados e cilindros protéticos plásticos fundidos com dois tipos de ligas metálicas básicas. MATERIAL E MÉTODOS: 05 amostras de (1) cilindros plásticos fundidos em liga de cobalto cromo; (2) cilindros plásticos fundidos em liga de níquel cromo e (3) cilindros pré-fabricados com cinta metálica em paládio, foram examinados na interface intermediário/cilindro protético na análise de desajuste marginal, considerando-se (A) desajuste vertical, (B) desajuste horizontal e (C) profundidade de fenda. RESULTADOS: os valores médios para o desajuste vertical, horizontal e profundidade foram, respectivamente, 4,13µm, 14,5µm e 6,93µm para o cilindro pré-fabricado em paládio, 23,18µm, 33,2µm e 88µm para os cilindros plásticos fundidos em Níquel cromo e 25,6µm, 51,8µm e 114,54 µm para os cilindros fundidos em cobalto-cromo. CONCLUSÃO: não foram encontradas diferenças estatísticas entre os grupos fundidos (grupo 1 e 2), mas uma adaptação marginal significantemente superior foi observada com os cilindros pré-fabricados quando comparado aos cilindros plásticos fundidos com níquel-cromo e cobalto-cromo para todas as análises

Effect of 0.2% peracetic acid disinfection on the horizontal dimension of implant framework indexed with two autopolymerized acrylic resins.

BackgroundTo minimize misfit between prosthesis and implant, the welding of the implant fixed partial denture (IFPD) framework is recommended and autopolymerized acrylic resin (AR) is the material of choice for the indexing process. As for any prosthetic device that comes into contact with saliva and blood in the oral cavity, IFPD indexed with AR must be disinfected before sending to the laboratory. However, disinfection procedures are often neglected for fear of shrinkage or distortion caused by a dimensional change of the acrylic resin. Peracetic acid is a high-level disinfectant agent at low concentrations and immersion time, with no reported toxic residues, and it is not inactivated in the presence of organic matter when compared to other disinfectants. This study aimed to evaluate the influence of 0.2% peracetic acid disinfectant solution after different storage media and times on the horizontal dimension of IFPD frameworks indexed with AR.Material and methodsIFPD frameworks were indexed with two AR: group 1 Duralay and group 2 Pattern Resin LS. Each group was further divided into five subgroups according to disinfection procedure and storage medium: no disinfection and dry storage, no disinfection and water storage, 0.2% peracetic acid disinfection and water storage, 0.2% peracetic acid disinfection and peracetic acid storage, and 0.2% peracetic acid disinfection and dry storage. The horizontal dimension of the specimens and an average was established for analysis. Measurements were performed at four different storage times (hours): T0, T24, T48, T168.ResultsNo statistical differences were found when T0 was compared to T168 for Pattern resin groups submitted to disinfection and storage in water (group 2b, p = 1.000) or peracetic acid solution (group 2c, p = 0.352). For Duralay groups, the use of peracetic acid solution did not affect the horizontal dimension of the specimens when T0 was compared to T168 only with water as a storage medium (group 1b, p = 1.000). Additionally, T0 did not differ from T24 for groups 1c (p = 0.553), 2b (p = 1.000), 2d (p = 0.234), and 2e (p = 1.000) and from T48 for groups 1d (p = 0.118) and 2b (p = 1.000).ConclusionWithin the studied conditions, the use of 0.2% peracetic acid can be safely used as a disinfectant solution regarding dimensional stability of AR-indexed IFPD until 7 days of storage. Horizontal discrepancies are dependent on acrylic resin type, time, and medium of storage

Uso da técnica de tomografia computadorizada cone Beam modificada para avaliação padronizada dos tecidos ósseo e gengival em implantodontia/ Use of the modified cone beam computed tomography technique for standardized assessment of Bone and gingival tissues in implant dentistry

Este estudo avaliou as dimensões da unidade dentogengival pré-operatória e mudanças nos tecidos ósseo e gengival na reabilitação com implante imediato pela técnica Soft Tissue Cone-Beam Computed Tomography (ST-CBCT). Trata-se de uma série de seis pacientes submetidos à reabilitação com implante imediato em área estética da maxila. Realizou-se as seguintes medidas no pré e no pós-operatório de 03 e 06 meses: Espessura do Osso Vestibular (EO), Distância da Crista Óssea Vestibular à Junção Amelocementária ou à coroa protética (AO), Distância da Crista Óssea Vestibular à Plataforma do Implante (AO), Espessura de Tecido Mole (EG) e Distância da Margem Gengival à Crista Óssea Vestibular (AG), submetidas à estatística descritiva (média e desvio-padrão). A EO aumentou nos pacientes 01 (1,03mm), 02 (0,66mm) e 06 (0,06mm) e reduziu nos pacientes 03 (0,17mm), 04 (0,41mm) e 05 (0,38mm). Nos pacientes 02 e 03 o osso vestibular estava no nível da plataforma do implante; nos demais pacientes os implantes permaneceram infra-ósseos. A EG aumentou nos pacientes 01 (0,30mm), 02 (0,80mm), 03 (1,27mm) e 06 (0,74mm) e houve redução na altura gengival dos pacientes 01 (-0,30mm), 03 (-0,04mm) e 05 (0,06mm). Houve divergência na classificação do biótipo gengival nos pacientes 03 e 05. A técnica ST-CBCT demonstrou ser um instrumento não invasivo valioso para avaliação dos tecidos ósseo e gengival no pré e pós-operatório de reabilitação com implantes imediatos e permitiu mensuração padronizada dos tecidos periimplantares a longo prazo

Avaliação do desajuste e do destorque em pilares protéticos com conexão tipo hexágono externo e interno

Objetivou-se com este trabalho foi avaliar o desajuste marginal e o efeito da aplicação de carga cíclica no destorque dos parafusos de retenção de pilares protéticos usinados, sobrefundidos e fundidos com conexão tipo hexágono externo (HE) e interno (HI). Foram avaliados 12 pilares protéticos para cada grupo com HE:(A1) usinados em titânio; (A2) com cinta metálica em paládio-prata, sobrefundidos com paládio-prata; (A3) plásticos fundidos em NiCr e (A4) plásticos fundidos em CoCr; e 12 pilares protéticos para cada grupo com HI: (B1) usinados em titânio e (B2) com cinta metálica em paládio-prata, sobrefundidos com paládio-prata. Foram realizadas análises de desajuste marginal (profundidade de fenda, desajuste vertical e horizontal) e de desajuste rotacional na interface implante/pilar protético. Os valores de destorque foram registrados antes e depois da aplicação de cargas cíclicas. As médias de cada grupo, para cada análise, foram calculadas e comparadas com ANOVA, Student-Newman Keuls (p<0,05). Os resultados obtidos foram: profundidade de fenda (µm): (A1) 54,1±127,75, (A2) 49,4±36,56, (A3) 21,2±21,36, (A4) 33,1±23,81, (B1) 8,4±13,74 e (B2) 34,9±20,49; desajuste horizontal (µm): (A1) 89,1 ± 14,15, (A2) 39,2 ± 16,87, (A3) 13,5 ± 9,48, (A4) 23,0 ± 21,42, (B1) 10,9 ± 5,68 e (B2) 18,2 ± 10,31; desajuste vertical (µm): (A1) 5,6 ± 6,46, (A2) 11,1 ± 8,22, (A3) 8,0 ± 9,35, (A4) 6,9 ± 3,78, (B1) 2,1 ± 3,21 e (B2) 12,1 ± 4,75; desajuste rotacional (em graus): (A1) 1,2 ± 0,57, (A2) 1,8 ± 1,31, (A3) 2,0 ± 0,73, (A4) 2,8 ± 1,14, (B1) 2,8 ± 1,08 e (B2) 2,0 ± 1,03; destorque inicial (%): (A1) 92,3 ±3,0, (A2) 81,6 ± 5,0, (A3) 86,4 ± 4,6, (A4) 84,0 ± 7,7, (B1) 88,8 ± 6,8 e (B2) 84,9 ± 2,4 e destorque final (%): (A1) 41,1 ± 19,3, (A2) 19,8 ± 13,0, (A3) 27,9 ± 6,5, (A4) 37,5 ± 16,2, (B1) 17,1 ± 16,2 e (B2) 23,3 ± 10,9. Para as análises de desajuste marginal, os resultados demonstraram que as diferenças entre pilares usinados, sobrefundidos e fundidos foram variáveis. Todos os grupos apresentaram desajuste rotacional inferior a 5º, indicando adequada estabilidade das conexões estudadas. Para a conexão tipo hexágono externo avaliada neste estudo, os pilares usinados apresentaram maior destorque inicial, entretanto, o destorque final foi igual para os pilares usinados e fundidos. O destorque final dos pilares usinados com hexágono externo avaliados neste estudo foi maior que dos pilares usinados com hexágono interno.Marginal misfit and the effect of cyclic loading on screw joint stability were analyzed for machined, cast-on and cast abutments with external and internal connection. Twelve samples from each abutment type for external hexagonal implants were included: (A1) machined titanium; (A2) metal premachined with plastic sleeve cast-on with palladium alloy; (A3) plastic abutment cast with NiCr alloy, and (A4) plastic abutment cast with CoCr alloy. And 24 samples for internal hexagonal implants: (B1) machined titanium, and (B2) metal premachined with plastic sleeve cast-on with palladium. Horizontal depth gap, vertical and horizontal gap and rotational misfit were analyzed at the implant/abutment interface. Detorque values were obtained for each group before and after cyclic loading. Mean values for each group for each analysis were evaluated for difference using ANOVA and Student-Newman Keuls. Results were: horizontal depth gap (A1) 54.1±127.75, (A2) 49.4±36.56, (A3) 21.2±21.36, (A4) 33.1±23.81, (B1) 8.4±13.74 and (B2) 34.9±20.49; horizontal gap: (A1) 89.1 ± 14.15, (A2) 39.2 ± 16.87, (A3) 13.5 ± 9.48, (A4) 23.0 ± 21.42, (B1) 10.9 ± 5.68 and (B2) 18.2 ± 10.31; vertical gap: (A1) 5.6 ± 6.46, (A2) 11.1 ± 8.22, (A3) 8.0 ± 9.35, (A4) 6.9 ± 3.78, (B1) 2.1 ± 3.21 and (B2) 12.1 ± 4.75; rotational misfit: (A1) 1.2 ± 0.57, (A2) 1.8 ± 1.31, (A3) 2.0 ± 0.73, (A4) 2.8 ± 1.14, (B1) 2.8 ± 1.08 and (B2) 2.0 ± 1.03; initial detorque: (A1) 92.3 ±3.0, (A2) 81.6 ± 5.0, (A3) 86.4 ± 4.6, (A4) 84.0 ± 7.7, (B1) 88.8 ± 6.8 and (B2) 84.9 ± 2.4 and final detorque: (A1) 41.1 ± 19.3, (A2) 19.8 ± 13.0, (A3) 27.9 ± 6.5, (A4) 37.5 ± 16.2, (B1) 17.1 ± 16.2 and (B2) 23.3 ± 10.9. Marginal gap analysis showed no major differences among all groups. All groups presented less than 5 degrees of rotational misfit, indicating good screw joint stability. External hexagonal machined abutments presented higher initial detorque than all groups, however, no differences were found for final detorque values when compared to cast-on and cast abutments. External hexagonal cast abutments presented higher final detorque when compared to cast-on abutments. External hexagonal machined abutments also presented higher final detorque values when compared to internal hexagonal machined abutments

Avaliação da Adaptação da Interface Intermediário/ Cilindro de Ouro e da Compatibilidade de Diferentes Sistemas de Implantes Odontológicos: Análise Inrta e Entre - Sistemas.

A adaptação passiva entre prótese e intermediário é considerada um requisito básico para o sucesso do tratamento protético em implantes odontológicos, embora pouco se saiba do grau de adaptação apresentado pelos componentes usinados, antes mesmo de serem utilizados. As diferentes soluções protéticas aumentaram o número de sistemas de implantes chamados compatíveis, mas existe uma dificuldade em prever a resposta biológica de um implante frente a estresses constantes, recomendando-se, em qualquer sistema utilizado, uma adaptação passiva. O objetivo deste trabalho foi avaliar a adaptação na interface intermediário e cilindro de ouro utilizando-se componentes de um mesmo sistema de implantes e combinações de componentes de diferentes sistemas. Componentes de 6 sistemas de implantes compatíveis foram utilizados: 3I, Lifecore, Conexão, Implamed, Nobelbiocare e NAPIO. Após a adaptação dos mesmos, o aperto dos parafusos foi padronizado com o auxílio de um torquímetro eletrônico. Os resultados da análise intra-sistema, após leitura em microscópio, não foram estatisticamente significantes entre os sistemas em relação ao desajuste (desajuste médio de 7,85µm), por outro lado, o melhor ajuste foi encontrado para os sistemas Nobelbiocare (94.44%) e Implamed (90.27%) e o pior para os sistemas Lifecore (33.33%) e 3I (26,38%). Analisados os resultados da análise entre-sistemas, sugere-se que nem todas as combinações podem ser consideradas compatíveis.The absolutely precise fit between prosthesis framework and abutment is very important for the long-term success of the implant-prosthetic treatment, although little is known about the fit of the machined components. The different prosthetic solutions has increased the number of implant systems that claim to be compatible" to all Branemark-like Systems, but due to the current impossibility to predict the biologic response of an implant under constant strain, it is highly recommended to achieve a passive fitting framework. The purpose of this investigation was to determine the fit and the compatibility within and between different implant systems components at the abutment/gold cylinder interface. Implants components from 3I, Lifecore, Conexão, Implamed, Nobelbiocare and NAPIO were evaluated. Assembly of the components were standardized by using an electronic torquing device. The within systems results for misfit were not different (mean=7,85µm), but the best fit was found for Nobelbiocare and Implamed components and the worst for Lifecore and 3I. The between-systems results suggest that compatibility can not be achieved with all combinations

Avaliação da Adaptação da Interface Intermediário/ Cilindro de Ouro e da Compatibilidade de Diferentes Sistemas de Implantes Odontológicos: Análise Inrta e Entre - Sistemas.

A adaptação passiva entre prótese e intermediário é considerada um requisito básico para o sucesso do tratamento protético em implantes odontológicos, embora pouco se saiba do grau de adaptação apresentado pelos componentes usinados, antes mesmo de serem utilizados. As diferentes soluções protéticas aumentaram o número de sistemas de implantes chamados compatíveis, mas existe uma dificuldade em prever a resposta biológica de um implante frente a estresses constantes, recomendando-se, em qualquer sistema utilizado, uma adaptação passiva. O objetivo deste trabalho foi avaliar a adaptação na interface intermediário e cilindro de ouro utilizando-se componentes de um mesmo sistema de implantes e combinações de componentes de diferentes sistemas. Componentes de 6 sistemas de implantes compatíveis foram utilizados: 3I, Lifecore, Conexão, Implamed, Nobelbiocare e NAPIO. Após a adaptação dos mesmos, o aperto dos parafusos foi padronizado com o auxílio de um torquímetro eletrônico. Os resultados da análise intra-sistema, após leitura em microscópio, não foram estatisticamente significantes entre os sistemas em relação ao desajuste (desajuste médio de 7,85µm), por outro lado, o melhor ajuste foi encontrado para os sistemas Nobelbiocare (94.44%) e Implamed (90.27%) e o pior para os sistemas Lifecore (33.33%) e 3I (26,38%). Analisados os resultados da análise entre-sistemas, sugere-se que nem todas as combinações podem ser consideradas compatíveis.The absolutely precise fit between prosthesis framework and abutment is very important for the long-term success of the implant-prosthetic treatment, although little is known about the fit of the machined components. The different prosthetic solutions has increased the number of implant systems that claim to be compatible" to all Branemark-like Systems, but due to the current impossibility to predict the biologic response of an implant under constant strain, it is highly recommended to achieve a passive fitting framework. The purpose of this investigation was to determine the fit and the compatibility within and between different implant systems components at the abutment/gold cylinder interface. Implants components from 3I, Lifecore, Conexão, Implamed, Nobelbiocare and NAPIO were evaluated. Assembly of the components were standardized by using an electronic torquing device. The within systems results for misfit were not different (mean=7,85µm), but the best fit was found for Nobelbiocare and Implamed components and the worst for Lifecore and 3I. The between-systems results suggest that compatibility can not be achieved with all combinations

Use of base metal casting alloys for implant framework: marginal accuracy analysis

The original protocol for implant prosthesis recommends the use of a gold framework for acrylic and ceramic prosthesis. However, due to its high cost, the use of alternative alloys is desired. This study compares the marginal accuracy of pre-made cylinders versus plastic cylinders cast with two different base metal casting alloys. Five samples each of (1) plastic cylinder cast in cobalt-chromium alloy, (2) plastic cylinder cast in nickel-chromium alloy, and (3) silver-palladium pre-made cylinder (control) were examined for marginal accuracy according to: (A) vertical gap; (B) horizontal gap and (C) horizontal gap depth at the abutment/cylinder interface. Data were submitted to statistical analysis (ANOVA and Student-Newman Keuls, p<0.05). Mean values for vertical, horizontal and gap depth were 4.13&micro;m, 14.5&micro;m and 6.93&micro;m for pre-made cylinder, 23.18&micro;m, 33.2&micro;m and 88&micro;m for Ni-Cr cast cylinder and 25.6&micro;m, 51.8&micro;m and 114.54&micro;m for Co-Cr cast cylinder. No statistically significant differences were found between cast groups (1 and 2), but significant better fit was obtained with pre-made metal cylinders when compared to cast cylinders with Ni-Cr and Co-Cr alloys, for all analyses

Influence of polishing systems on roughness and color change of two dental ceramics

Made available in DSpace on 2019-09-20T14:08:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2019PURPOSE. To evaluate the polishing effect on roughness and color change of pressed and layering ceramics after immersion in coffee solution. MATERIALS AND METHODS. 88 ceramic discs (1.0 mm x 10.0 mm) were manufactured - 44 nano-fluorapatite layering ceramics (IPS e.max Ceram. Group C) and 44 pressed lithium disilicate ceramic discs (IPS e. max Press - Group P). Each group was divided into 4 subgroups according to surface treatments: (G) Glaze, (S) Shofu polishing system (Shofu Inc.), (E) Edenta AG polishing System, (KG) 30-pm diamond granulation tip. Surface roughness (Ra) and color change (Delta E) measurings after the surface treatments were performed, before and 12 days after the immersion in coffee solution. A sample's qualitative analysis was conducted with a scanning electron microscopy (SEM). Data were statistically-treated with oneway-ANOVA and Duncan's tests, apart from paired t-test and Pearson's correlation test (alpha=5%). RESULTS. The decrescent order, both for surface roughness (Ra) and Delta E for both ceramics were: KG > E > S > G (P<.05). With exception for PG and CG subgroups, which did not present statistical difference between them, all other pressed ceramics subgroups presented smaller Ra values and greater Delta E values than the layering ceramics subgroups (P<.05). CONCLUSION. Although mechanical polishing systems presented intermediate Ra values, their colors were considered clinically acceptable. There is a strong correlation between the surface roughness and the color change of tested ceramics.[Maciel, Lucas Campagnaro; da Silva Concilio, Lais Regiane] Univ Taubate UNITAU, Dent Sch, Taubate, SP, Brazil[Bettcher Silva, Carlos Frederico] Sch Higher Educ Sao Francisco Assis ESFA, Dent Sch, Santa Teresa, ES, Brazil[de Jesus, Ricardo Huver] Univ Veiga de Almeida, Dent Sch, Rio de Janeiro, RJ, Brazil[Kano, Stefania Carvalho; Xible, Anuar Antonio] Fed Univ Espirito Santo UFES, Dent Sch, Vitoria, ES, Brazi

Use of base metal casting alloys for implant framework: marginal accuracy analysis

The original protocol for implant prosthesis recommends the use of a gold framework for acrylic and ceramic prosthesis. However, due to its high cost, the use of alternative alloys is desired. This study compares the marginal accuracy of pre-made cylinders versus plastic cylinders cast with two different base metal casting alloys. Five samples each of (1) plastic cylinder cast in cobalt-chromium alloy, (2) plastic cylinder cast in nickel-chromium alloy, and (3) silver-palladium pre-made cylinder (control) were examined for marginal accuracy according to: (A) vertical gap; (B) horizontal gap and (C) horizontal gap depth at the abutment/cylinder interface. Data were submitted to statistical analysis (ANOVA and Student-Newman Keuls, p<0.05). Mean values for vertical, horizontal and gap depth were 4.13&micro;m, 14.5&micro;m and 6.93&micro;m for pre-made cylinder, 23.18&micro;m, 33.2&micro;m and 88&micro;m for Ni-Cr cast cylinder and 25.6&micro;m, 51.8&micro;m and 114.54&micro;m for Co-Cr cast cylinder. No statistically significant differences were found between cast groups (1 and 2), but significant better fit was obtained with pre-made metal cylinders when compared to cast cylinders with Ni-Cr and Co-Cr alloys, for all analyses