Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 484
Filter
1.
Braz. j. oral sci ; 21: e224265, jan.-dez. 2022. tab
Article in English | LILACS, BBO | ID: biblio-1354719

ABSTRACT

Aim: This study assessed the color and translucency stability of a polymer infiltrated ceramic network (PICN) and compared it with a resin composite (RC) and a feldspathic ceramic (FEL). Methods: Disc-shaped samples of a PICN (Vita Enamic), a feldspathic ceramic (Vitablocks Mark II), and a resin composite (Brava block) were prepared from CAD/CAM blocks. PICN and RC surfaces were finished with a sequence of polishing discs and diamond paste. FEL samples received a glaze layer. The samples were subjected to 30-min immersions in red wine twice a day for 30 days. CIEL*a*b* coordinates were assessed with a spectrophotometer at baseline and after 15 and 30 days of immersion. Color alteration (ΔE00) and translucency parameter (TP00) were calculated with CIEDE2000. Average roughness was measured before the staining procedures. Color difference and translucency data were analyzed with repeated-measures ANOVA and Tukey's tests. Roughness was analyzed with the Kruskal-Wallis test. Results: Roughness was similar among the experimental groups. All materials had their color alteration significantly increased from 15 to 30 days of staining. PICN reached an intermediate ΔE00 between FEL and RC at 15 days. PICN revealed a color alteration as high as the composite after 30 days. No statistical difference was observed regarding translucency. Conclusion: PICN was not as color stable as the feldspathic ceramic at the end of the study. Its color alteration was comparable to the resin composite when exposed to red wine. However, the translucency of the tested materials was stable throughout the 30-day staining


Subject(s)
Surface Properties , Materials Testing , Ceramics , Computer-Aided Design , Color , Composite Resins
2.
Braz. dent. sci ; 25(1): 1-8, 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1354530

ABSTRACT

Several treatment options for replacement of anterior missing teeth exist, varying from no-prep (no preparation) adhesive restorations to implants. Patients' biological, psychological, economic conditions or age have an effect on the treatment choice. It is important to perform the most conservative and beneficial treatment option considering the patient based factors. The aim of this case report was to demonstrate a single session, minimally invasive, cantilevered 2-unit all-ceramic restorations replacing anterior missing teeth combined with the advantages of CAD/CAM technology and materials. (AU)


Existem várias opções de tratamento para reabilitação de dentes anteriores ausentes, variando de restaurações adesivas sem preparo (sem preparação) até implantes. As condições biológicas, psicológicas, econômicas ou a idade dos pacientes têm um efeito na escolha do tratamento. É importante realizar a opção de tratamento mais conservadora e benéfica, considerando os fatores baseados no paciente. O objetivo deste relato de caso foi demonstrar em sessão única, minimamente invasiva, um cantiléver de restaurações de cerâmica pura de 2 unidades, reabilitando a região de dentes anteriores ausentes combinadas com as vantagens da tecnologia CAD/CAM.(AU)


Subject(s)
Humans , Male , Adult , Denture, Partial, Fixed, Resin-Bonded , Dental Prosthesis , Computer-Aided Design
3.
Braz. dent. sci ; 25(1): 1-11, 2022. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1354726

ABSTRACT

Objective: To compare the three different methods of complete denture fabrication assessing patient satisfaction and retention after insertion for six months' follow-up period. Material and Methods: The study was conducted in the Prosthodontic Department where a total of forty-eight patients were recruited from the outpatient clinics fulfilling the inclusion criteria. This study was designed as a randomized controlled clinical trial. All patients followed the steps of complete denture construction till jaw relation record. Then, all eligible patients were randomized to intervention and control groups. For intervention groups digital scanning, designing, manufacturing of complete dentures was done; 3D printing for first and milling for second intervention. For the comparator group, complete dentures were manufactured the conventional way. After 2 weeks of delivery of the dentures, patients received a patient satisfaction questionnaire, retention was measured by retention force gauge. Both readings were also recorded after 3 months and at 6 months. The mean and standard deviation values were calculated for each group in each test. The significance level was set at P≤ 0.05. Results: No statistical difference was found in terms of patient satisfaction and retention between the three groups at different time intervals. Conclusion: The manufacturing technique seemed to have no influence on patient satisfaction and retention with milled showing the least results.(AU)


Objetivo: Comparar três métodos diferentes de fabricação de prótese total avaliando a satisfação do paciente e a retenção após a inserção por um período de acompanhamento de seis meses. Material e Métodos: O estudo foi conduzido no departamento de Prótese onde um total de quarenta e oito pacientes foram recrutados das clínicas ambulatoriais atendendo os critérios de inclusão. Este estudo foi designado como um ensaio clínico randomizado controlado. Todos os pacientes seguiram as mesmas etapas de confecção de prótese total até o registro da relação maxilo-mandibular. Então, todos os pacientes qualificados foram divididos de forma aleatória nos grupos de intervenção e grupo controle. Para os grupos de intervenção foram realizados escaneamento digital, projeto e fabricação de próteses totais; Impressão 3D para o primeiro e fresagem para o segundo grupo de intervenção. Para o grupo de comparação, próteses totais foram feitas com o método convencional. Depois de 2 semanas após a entrega das próteses os pacientes receberam um questionário de satisfação e a retenção foi mensurada com um medidor de força de retenção. Ambas as leituras também foram registradas após 3 e 6 meses. Os valores de média e desvio padrão foram calculados para cada grupo em cada teste. O nível de significância foi estabelecido em P ≤ 0,05. Resultados: Nenhuma diferença estatística foi encontrada em termos de satisfação do paciente e retenção entre os três grupos em diferentes intervalos de tempo. Conclusão: A técnica de fabricação pareceu não ter influência na satisfação do paciente e retenção da prótese, com o grupo fresado apresentando o mínimo de resultados.(AU)


Subject(s)
Patient Satisfaction , Dental Prosthesis Retention , Computer-Aided Design , Denture, Complete , Printing, Three-Dimensional
4.
Pesqui. bras. odontopediatria clín. integr ; 22: e210044, 2022. tab, graf
Article in English | LILACS, BBO | ID: biblio-1365224

ABSTRACT

ABSTRACT Objective To assess the effects of coloring beverages on the color stability of two types of hybrid ceramics with different surface treatments. Material and Methods 180 specimens of two hybrid ceramics (Vita Enamic and Mazic Duro) and a feldspathic ceramic (Vita Mark II) were prepared (n=60 in each group). Half of the discs in each group were glazed while the other was polished. The specimens were then divided into three subgroups and immersed in distilled water, carrot juice, and coffee. The overall color difference (∆E) was calculated based on CIE L*a*b* color space. Data were analyzed using three-way and one-way ANOVA; Tukey's honest significant difference was also done for pairwise comparisons (α=0.05). Results Vita Mark II specimens revealed less overall color changes compared to other groups. The ∆E of the glazed Vita Enamic specimens was greater than polished specimens following immersion in distilled water (p=0.03) and coffee (p=0.001), but it was not significant for carrot juice. The same results were obtained for polished Mazic Duro specimens. Relatively similar amounts of ∆E were recorded in polished and glazed subgroups of Vita Mark II. Conclusion The ∆E of hybrid ceramics was higher than Vita Mark II. Polishing could be recommended for surface treatment of hybrid ceramics instead of glazing, saving time and facilitating the process.


Subject(s)
Spectrophotometry/instrumentation , Surface Properties , Beverages , Color , Dental Cements , Distilled Water , Ceramics , Analysis of Variance , Dental Prosthesis , Computer-Aided Design/instrumentation , Coffee , Dental Porcelain , Coloring Agents , Fruit and Vegetable Juices , Iran/epidemiology
5.
Braz. j. oral sci ; 20: e214873, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1254742

ABSTRACT

Aim: To compare the marginal fit of lithium disilicate CAD/CAM crowns and heat-pressed crowns fabricated using milled wax patterns, and evaluate its effect on stress distribution in implantsupported rehabilitation. Methods: A CAD model of a mandibular first molar was designed, and 16 lithium disilicate crowns (8/group) were obtained. The crown-prosthetic abutment set was evaluated in a scanning electron microscopy. The mean misfit for each group was recorded and evaluated using Student's t-test. For in silico analysis, a virtual cement thickness was designed for the two misfit values found previously, and the CAD model was assembled on an implant-abutment set. A load of 100 N was applied at 30° on the central fossa, and the equivalent stress was calculated for the crown, titanium components, bone, and resin cement layer. Results: The CAD/CAM group presented a significantly (p=0.0068) higher misfit (64.99±18.73 µm) than the heat-pressed group (37.64±15.66 µm). In silico results showed that the heat-pressed group presented a decrease in stress concentration of 61% in the crown and 21% in the cement. In addition, a decrease of 14.5% and an increase of 7.8% in the stress for the prosthetic abutment and implant, respectively, was recorded. For the cortical and cancellous bone, a slight increase in stress occurred with an increase in the cement layer thickness of 5.9% and 5.7%, respectively. Conclusion: The milling of wax patterns for subsequent inclusion and obtaining heat-pressed crowns is an option to obtain restorations with an excellent marginal fit and better stress distribution throughout the implant-abutment set


Subject(s)
Microscopy, Electron, Scanning , Computer-Aided Design , Dental Marginal Adaptation , Dental Prosthesis, Implant-Supported , Finite Element Analysis , Dental Materials
6.
Rev. Odontol. Araçatuba (Impr.) ; 42(3): 25-31, set.-dez. 2021. ilus
Article in Portuguese | LILACS, BBO | ID: biblio-1284114

ABSTRACT

Os pilares personalizados são usados em reabilitações protéticas sobre implantes quando há exigências de angulação, perfil de emergência e margem gengival, em que os pilares convencionais não conseguem reabilitar de forma correta os conceitos de forma, função e estética. Através de um relato de caso clínico, onde houve a reabilitação dos elementos 21 e 22, com o uso de implante e próteses, usando o pilar personalizado em zircônia sobre o implante do 22, confeccionado com a tecnologia CAD/CAM. Esse sistema de pilares personalizados oferecem o desenho mais próximo do ideal e o ajuste mais perfeito em relação ao implante e ao tecido gengival, além de considerar as vantagens e desvantagen em relação aos pilares convencionais pré-fabricados nas questões de tempo de tratamento, custos e resultado estético e biológico. Concluimos que a reabilitação com pilares personalizados CAD/CAM confere uma excelente alternativa reabilitadora, devolvendo função e estética aos pacientes, desde que haja conhecimento adequado por parte dos profissionais envolvidos(AU)


Custom abutments are used in prosthetic rehabilitation on implants when angulation, emergence profile and gingival margin are used, where abutments are not recovered in a correct way to rehabilitate the concepts of shape, functions and aesthetics. Through a clinical case, where the elements 21 and 22 were rehabilitated, with the use of implants and practices, using the personalized abutments in zirconia, made with CAD / CAM technology. This customized system and abutments offers the closest ideal design and the most perfect fit in relation to the implant and gingival tissue, in addition to considering advantages and disadvantages in relation to the prefabricated applied abutments in terms of treatment time, costs and results aesthetic and biological. Conclude that a rehabilitation with customized CAD / CAM abutments provides an excellent rehabilitation alternative, returning function and aesthetics to patients, as long as there is adequate knowledge for part of the professionals involved(AU)


Subject(s)
Humans , Female , Aged , Dental Implants , Computer-Aided Design , Biocompatible Materials , Dental Prosthesis, Implant-Supported , Esthetics, Dental
7.
Rev. cuba. estomatol ; 58(2): e3265, 2021. tab, graf
Article in Spanish | LILACS, CUMED | ID: biblio-1289407

ABSTRACT

Introducción: Gracias a su eficiencia y al uso exclusivo de cerámicas libres de metal, en rehabilitación oral se ha logrado alcanzar los estándares estéticos y mecánicos, manteniendo o, incluso, superando, la calidad de los tratamientos en comparación con las restauraciones metal cerámicas tradicionales. Actualmente los mecanismos de confeccion de cerámica libre están evolucionando cada vez mas hacia las tecnologías maquinadas CAD-CAM y disminuyendo su producción mediante la técnica de Inyeccion PRESS. Objetivo: Comparar la tasa de supervivencia de prótesis fija unitaria realizadas con cerámicas feldespáticas convencionales y reforzadas con disilicato de litio, confeccionadas con sistema CAD/CAM de CEREC® chair-side, en comparación con el método de inyección de laboratorio PRESS convencional de prensión. Métodos: Revisión sistemática realizada a través de búsqueda de evidencia científica en PubMed, PubMed Clinical Queries, Epistemónikos, Tripdatabase, Cochrane Library, recursos electrónicos de la Universidad de los Andes y bibliografía retrógrada, de artículos publicados hasta el año 2019. Se incluyeron todos aquellos estudios referentes a prótesis fija unitaria de cerámicas feldespática convencional y feldespática reforzada con disilicato de litio, confeccionadas mediante CAD/CAM y/o método convencional. Resultados: Un total de 28 artículos cumplieron los criterios de inclusión: 21 estudios observacionales de cohorte, 4 ensayos clínicos aleatorizados y 3 no aleatorizados. A corto y mediano plazo, CAD/CAM de CEREC® registró tasas de supervivencia de 98 por ciento y 91,9 por ciento, respectivamente. El sistema convencional registró tasas de supervivencia de 97,5 por ciento a corto plazo y 93 por ciento a mediano. Conclusiones: A corto plazo se describe en la literatura que CAD/CAM de CEREC® tuvo una tasa de supervivencia ligeramente superior al sistema convencional. Por otro lado, a mediano plazo CAD/CAM de CEREC® presentó una leve disminución respecto al sistema convencional. Aún no hay estudios disponibles para determinar la supervivencia clínica de los tratamientos a largo plazo(AU)


Introduction: Thanks to its efficiency and the exclusive use of metal-free ceramics, in oral rehabilitation it has been possible to achieve aesthetic and mechanical standards, maintaining or even exceeding the quality of the treatments compared to traditional metal-ceramic restorations. Currently, free ceramic manufacturing mechanisms are increasingly evolving towards CAD-CAM machined technologies and decreasing their conventional production through the PRESS Injection technique. Objective: Compare the survival rate of single-unit fixed prostheses made with conventional feldspathic ceramics and reinforced with lithium disilicate by the CEREC® CAD/CAM chairside system, with the conventional PRESS laboratory injection method. Methods: A systematic review was conducted of scientific evidence included in papers published until the year 2019 in PubMed, PubMed Clinical Queries, Epistemonikos, Tripdatabase, Cochrane Library, electronic resources of Los Andes Peruvian University, and retrograde bibliography. The papers selected dealt with conventional and lithium-disilicate reinforced feldspathic ceramic single-unit prostheses made by CAD/CAM and/or the conventional method. Results: A total 28 papers met the inclusion criteria. Of these, 21 were observational cohort studies, four were randomized clinical assays and three were non-randomized assays. Short- and mid-term, CEREC® CAD/CAM achieved survival rates of 98 percent and 91.9 percent, respectively. The conventional system achieved survival rates of 97.5 percent short-term and 93 percent mid-term. Conclusions: As described in the literature, CEREC® CAD/CAM had a slightly higher survival rate than the conventional system in the short term. In the medium term, however, CEREC® CAD/CAM displayed a slight reduction in comparison with the conventional system. No studies are available to determine the clinical survival of the treatments in the long term(AU)


Subject(s)
Humans , Ceramics/adverse effects , Dental Prosthesis Design/methods , Computer-Aided Design/trends , Denture, Partial, Fixed/adverse effects , Review Literature as Topic , Survival Rate , Cohort Studies , Observational Studies as Topic , Esthetics, Dental
8.
Braz. dent. j ; 32(3): 44-55, May-June 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1345505

ABSTRACT

Abstract In the RLT (Rapid Layer Technology), veneering ceramic and framework are fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) and then cemented to obtain the restoration. This study aimed to evaluate the effect of the thickness of veneering ceramic manufactured by the RLT technique on the fracture resistance (FR) of bilayer crowns with zirconia frameworks. Twenty zirconia frameworks and twenty feldspathic posterior crowns with two different veneering ceramic occlusal thicknesses (1mm=TF1; 2mm=TF2) were manufactured using CAD/CAM system. The specimens were luted to an epoxy resin abutment with resin cement and mechanically cycled (200N and 4.5×105 Pa, 37°C, 2×106 cycles, 3Hz). The FR test was performed (10kN, 0.5mm/min), and the specimens were analyzed in a stereomicroscope. For the stress analysis (finite element analysis, FEA), a 10kN load was equal to the in vitro test, and the principal stress was evaluated. The FR data were analyzed by Student's t-test and Weibull's analysis. The thickness influenced the FR of bilayer crowns. The FR was higher in the TF2 than in the TF1 group. The TF2 group presented the highest characteristic strength compared to the group TF1. The predominant type of failure was delamination. The FEA showed higher stress concentrations below the loading application point at the veneering cement interface in the 1-mm-thick model. The bilayer crowns manufactured using the approach of 2mm of veneering ceramic promoted higher FR compared to the group with 1mm veneering ceramic. Also, the FEA showed that the veneer ceramic thickness has an effect on stress distribution in zirconia-based bilayer crowns.


Resumo Na RLT (Rapid Layer Technology), a cerâmica de cobertura e infraestrutura são fabricados pelo Computer-Aided Design / Computer-Aided Manufacturing (CAD / CAM) e cimentados para obter a restauração. Este estudo teve como objetivo avaliar o efeito da espessura da cerâmica de cobertura fabricada pela técnica RLT na resistência à fratura (RF) de coroas bilaminadas com infraestrutura de zircônia. Vinte infraestruturas de zircônia e vinte coroas posteriores feldspáticas com duas espessuras oclusais da cerâmica de cobertura (1mm = TF1; 2mm = TF2) foram fabricadas usando o sistema CAD / CAM. Os espécimes foram cimentados em preparos de resina epóxi com cimento resinoso dual e ciclados mecanicamente (200N e 4,5×105 Pa, 37° C, 2×106 ciclos, 3Hz). O teste de RF foi realizado (10kN, 0,5mm / min) e, posteriormente, os espécimes foram analisados em estereomicroscópio. Para a análise de tensão (análise de elementos finitos, FEA), uma carga de 10kN foi aplicada igual ao teste in vitro, e a tensão principal foi avaliada. Os dados de RF foram analisados pelo teste t de Student e análise de Weibull. A espessura mostrou forte influência na RF das coroas bilaminadas. A RF foi maior em TF2 do que no grupo TF1. O grupo TF2 apresentou a maior resistência característica em relação ao grupo TF1. O tipo de falha predominante foi a delaminação. O FEA mostrou maiores concentrações de tensões abaixo do ponto de aplicação da carga, na interface cimento e cerâmica de cobertura no modelo de coroa de 1 mm de espessura. As coroas de bilaminadas confeccionadas com 2 mm de cerâmica de cobertura promoveram maior RF em comparação ao grupo com cerâmica de cobertura de 1 mm. Além disso, a FEA mostrou que a espessura da cerâmica de cobertura tem um efeito na distribuição de tensões em coroas bilaminadas à base de zircônia.


Subject(s)
Humans , Dental Porcelain , Dental Veneers , Technology , Zirconium , Materials Testing , Ceramics , Computer-Aided Design , Dental Restoration Failure , Crowns , Dental Stress Analysis
9.
Braz. dent. j ; 32(3): 56-64, May-June 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1345501

ABSTRACT

Abstract It aims on evaluate the effect of the test environment on static fatigue behavior of lithium disilicate-based (LD), and yttrium oxide-stabilized zirconia (YSZ) ceramics. Specimens of LD (IPS e.max CAD, Ivoclar Vivadent) and YSZ (IPS e.max ZirCAD MO, 3 mol% Y2O3, Ivoclar Vivadent) were randomly allocated into three groups: tested in air, inert (paraffin oil, Sigma Aldrich) or distilled water. The static fatigue test (n=15) was performed using a piston-on-three ball assembly, adapted from ISO 6872, as follows: starting load 100 N for LD and 300 N for YSZ; loading application time set to 1 hour for each loading step; step size of 50 N for LD and 100 N for YSZ, applied successively until fracture. Data from static fatigue strength (MPa) and time to fracture (hours) were recorded. Fractographic analysis was executed. Survival analysis corroborates absence of influence of environment on static fatigue outcomes (fatigue strength, time to fracture and survival rates) for YSZ. For LD, specimens tested in air presented statistically superior survival rate and static fatigue strength (p= 0.025). In regards of time to fracture, LD tested in air were superior than when tested in distilled water (p=0.019) or inert (p=0.017) environments. No statistical differences for Weibull modulus were observed. Failures started on the tensile stress surface. Thus, the test environment did not affect slow crack growth (SCG) mechanisms during static fatigue test of YSZ ceramics, but it plays a significant role for the static fatigue behavior of lithium disilicate-based glass ceramics, indicating a high susceptibility to SCG.


Resumo O presente estudo objetivou investigar a influência do ambiente de teste no comportamento a fadiga estática (resistência à fratura e tempo para falha) de cerâmicas à base de dissilicato de lítio (LD) e zircônia estabilizada com ítria (YSZ). Espécimes de LD (IPS e.max CAD, Ivoclar Vivadent) e YSZ (IPS e.max ZirCAD MO, 3mol% Y2O3, Ivoclar Vivadent) foram obtidos e alocados aleatoriamente em três grupos: testado em ar, em líquido inerte (óleo de parafina) ou em água destilada. O teste de fadiga estática (n= 15) foi realizado usando o teste pistão sobre três esferas, ISO 6872, da seguinte forma: carga inicial 100 N para LD e 300 N para YSZ; tempo de aplicação de carregamento definido para 1 hora para cada etapa de carregamento; tamanho do passo de 50 N para LD e 100 N para YSZ, aplicados sucessivamente até a fratura. Dados de resistência à fadiga estática (MPa) e tempo até a fratura (horas) foram registrados. A análise fractográfica foi executada. A análise de sobrevivência corrobora a ausência de influência do ambiente de teste nos resultados de fadiga estática (resistência à fadiga, tempo de fratura e taxas de sobrevivência) para a YSZ. Para LD, os corpos de prova testados em ar apresentaram taxa de sobrevivência e resistência à fadiga estática estatisticamente superiores (p= 0,025). Em relação ao tempo de fratura, os espécimes LD testados em ar foram superiores aos testados em água destilada (p= 0,019) ou em ambiente inerte (p= 0,017). Não foram observadas diferenças estatísticas para o módulo de Weibull. Todas as falhas começaram no lado onde se concentra a tensão de tração (lado de baixo) durante o teste. Com base nisso, observa-se que o ambiente de teste não afetou os mecanismos de crescimento lento de trinca durante o teste de fadiga estática da cerâmica YSZ, mas desempenha um papel significativo na resistência à fadiga estática da cerâmica de vidro à base de dissilicato de lítio, indicando alta susceptibilidade ao crescimento lento e subcrítico de trincas.


Subject(s)
Ceramics , Dental Porcelain , Surface Properties , Zirconium , Materials Testing , Computer-Aided Design , Dental Stress Analysis , Glass
10.
São José dos Campos; s.n; 20210000. 66 p. ilus, graf.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1358950

ABSTRACT

O presente trabalho teve como objetivos: (1) relatar uma série de casos e apresentar uma metodologia para medição de desgaste usando software de metrologia comparando dois tipos de materiais em blocos CAD-CAM (dissilicato de lítio e resina composta) usados para restaurações onlay; (2) avaliar, in silico, a distribuição de tensões de dois materiais restauradores, IPS emax CAD e Grandio Blocs, em dois tipos de desenho de preparo dentário para onlay envolvendo cúspides funcionais ou não funcionais. (1) O estudo clínico foi registrado para avaliação do comitê de ética local e foi realizado com voluntários que necessitaram de procedimento restaurador indireto, seguindo os critérios de inclusão/exclusão. Quatro restaurações do tipo onlay (IPS emax CAD e GrandioBlocs) foram confeccionadas pelo método CAD-CAM chairside por um único operador treinado. A alocação dos tratamentos foi feita de forma aleatória. Após a cimentação das restaurações, a avaliação foi feita por examinador calibrado, não sendo o operador, nos períodos de 7 dias, 6 meses e 1 ano. Neste estudo foi analisada a quantidade de desgaste das restaurações por software de medição de dados (Gom Inspect) com acompanhamento de 6 meses e 1 ano com 4 pacientes avaliados sendo 2 restaurações de GrandioBlocs e 2 para IPS emax CAD. O resultado foi representado por um mapeamento de cores onde cada tonalidade representa uma quantidade de desgaste. O resultado obtido pelas imagens foi insignificante mostrando leve diferença nas imagens com restauração de GrandioBlocs. (2) Os molares foram modelados em quatro desenhos de preparação para restauração onlay: preparo tradicional com cobertura da cúspide funcional (TFC), preparo não retentivo com cobertura da cúspide funcional (NFC), preparo tradicional com cobertura da cúspide não funcional (TNFC), preparo não retentivo com cobertura de cúspide não funcional (NNFC). As restaurações foram simuladas com dois materiais restauradores CAD / CAM: LD - dissilicato de lítio (IPS emax CAD) e RC - resina composta (GrandioBlocs). Uma carga axial de 100 N foi aplicada à superfície oclusal simulando o ponto de contato cêntrico. As tensões de Von Mises (VM) e as tensões principais máximas (Pmax) foram avaliadas tanto para restaurações onlay, camada de cimento e substrato dentário. O desenho do preparo não retentivo melhorou a concentração de tensões na estrutura dentária em comparação com o desenho retentivo convencional. Para as onlays LD, a distribuição de tensões na superfície interna da restauração mostrou que o desenho da preparação influenciou a distribuição de tensões, bem como a opção de cúspide preparada. O desenho do preparo não retentivo proporcionou melhor distribuição de carga em ambos os materiais restauradores e mais vantajoso para a estrutura dentária. A restauração de resina composta em cúspides não funcionais é recomendada quando a cúspide funcional está preservada, para ser mais conservadora.


The aim of the present study was (1) to report a series of cases and to present a methodology for measurement of wear using metrology software comparing two types of CAD-CAM materials (lithium disilicate and composite resin) used for onlay restorations; (2) to evaluate, in silico, the stress distribution of two restorative materials, IPS emax CAD and Grandio Blocs, in two types of dental preparation design for onlay involving functional or non-functional cusps. (1) The clinical study was registered for evaluation by the local ethics committee and was carried out with volunteers who needed an indirect restorative procedure, following the inclusion / exclusion criteria. Four onlay restorations (IPS emax CAD and Grandio Blocs) were made using the chairside CAD-CAM method by a single trained operator. The allocation of treatments was done at random. After the cementation of the restorations, the assessment was made by a calibrated examiner, not being the operator, in the periods of 7 days, 6 months and 1 year. In this study, the amount of wear of the restorations was analyzed by data measurement software with 6-month and 1-year follow-up with 4 patients evaluated, 2 of which were GrandioBlocs and 2 for , IPS emax CAD restorations. The result is represented by a color mapping where each shade represents a quantity of wear. The result obtained by the images was insignificant, showing a slight difference in the images with restoration of GrandioBlocs. (2) Molars were modeled in four preparation designs for onlay restoration: traditional design with functional cusp coverage (TFC), non- retentive design with functional cusp coverage (NFC), traditional design with non-functional cusp coverage (TNFC), non-retentive design with non-functional cusp coverage (NNFC). Restorations were simulated with two CAD-CAM restorative materials: LD - lithium-disilicate (IPS emax CAD) and RC - resin composite (GrandioBloc). A 100 N axial load was applied to the occlusal surface simulating the centric contact point. Von Mises (VM) and maximum principal (Pmax) stresses were evaluated for onlay restorations, the cement layer and the dental substrate. The non-retentive preparation design improved the stress concentration in the tooth structure in comparison to the conventional retentive design. For LD onlays, the stress distribution on the restoration intaglio surface showed that the preparation design influenced the stress distribution as well as the prepared cusp option. The design of non-retentive preparation provided better load distribution in both restorative materials and more advantageous for tooth structure. The resin composite restoration on non- functional cusp is recommended when functional cusp is preserved, in order to be more conservative.


Subject(s)
Ceramics , Computer-Aided Design , Composite Resins , Finite Element Analysis , Inlays
11.
Rev. Cient. CRO-RJ (Online) ; 6(1): 39-44, abr. 2021.
Article in English | LILACS, BBO | ID: biblio-1354415

ABSTRACT

Introduction: Biocorrosion is a multifactorial disorder that causes dissolution of hard tissues by extrinsic/ intrinsic factors. Traditionally, restoring biocorrosion wear involves invasive preparations. Objective: This case report aims to describe the rehabilitation of biocorrosion with a minimally invasive approach (thin occlusal and vestibular ceramic laminates) in a fully digital workflow using natural algorithms. Case report: A 23-year-old patient was presented to clinic with generalized tooth wear associated to dentin hypersensitivity. In anamnesis, eating disorders and acid food consumption were reported, supporting the diagnosis of biocorrosion. The restoration of worn tissues involved an additive approach (minimizing additional wear), using a face guided planning protocol and a natural tooth anatomy database to achieve greater naturalness at the final restorations. Rehabilitation of worn tissues was performed using occlusal, anterior ceramic veneers and additive composite restorations. The patient's natural teeth characteristics were preserved, restoring aesthetic and self-esteem, and after 2- year follow-up the patient remains very satisfied. Conclusion: Additive approaches involving the least amount of tissue wear are essential for the biocorrosion restoration. In addition, the integration of natural algorithms to digital workflows brings more aesthetic and precision to definitive restorations, overcoming one of the main challenges of milled aesthetic restorations: the naturalness.


Introdução: A biocorrosão é uma desordem multifatorial que causa a dissolução dos tecidos duros por fatores extrínsecos/intrínsecos. Tradicionalmente, a restauração do desgaste por biocorrosão envolve preparações invasivas. Objetivo: Este relato de caso tem como objetivo descrever a reabilitação da biocorrosão com uma abordagem minimamente invasiva (laminados cerâmicos oclusais e vestibulares finos) em um fluxo de trabalho totalmente digital usando algoritmos naturais. Relato de caso: Paciente de 23 anos foi atendido na clínica com desgaste dentário generalizado associado à hipersensibilidade dentinária. Na anamnese, foram relatados transtornos alimentares e consumo de alimentos ácidos, corroborando o diagnóstico de biocorrosão. A restauração de tecidos desgastados envolveu uma abordagem aditiva (minimizando o desgaste adicional), usando um protocolo de planejamento guiado pela face e um banco de dados de anatomia natural do dente para obter maior naturalidade nas restaurações finais. A reabilitação dos tecidos desgastados foi realizada usando facetas oclusais, anteriores de cerâmica e restaurações de resina composta aditiva. As características dos dentes naturais do paciente foram preservadas, restabelecendo a estética e a autoestima, e após 2 anos de acompanhamento o paciente continua muito satisfeito. Conclusão: As abordagens aditivas que envolvem o menor desgaste tecidual são essenciais para a restauração da biocorrosão. Além disso, a integração de algoritmos naturais aos fluxos de trabalho digitais traz mais estética e precisão às restaurações definitivas, superando um dos principais desafios das restaurações estéticas fresadas: a naturalidade.


Subject(s)
Tooth Erosion , Tooth Diseases , Computer-Aided Design , Dental Veneers , Tooth Wear
12.
Braz. dent. sci ; 24(2): 1-7, 2021. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1178409

ABSTRACT

Background: To present the benefits of high power lasers (Er: YAG and Nd: YAG) over the use of the high speed turbine for the extraction of ceramics restorations, without damaging the surfaces of the teeth; being a relatively easier and faster procedure without the use of anesthetic agents, and the preparation of the ceramic restorations and cementing in the single session; with a follow-up of 1 year. Objective: The benefits of lasers over high-speed turbine mechanical instrumentation for crown removal encompass efficient restoration recovery without damage to tooth surfaces; and a relatively easier and faster procedure without the use of anesthetic agents. Methods: The Er: YAG laser (no contact; 3.2-4.0 W, 20 Hz) was used to extract the porcelain prosthesis, followed by a gingivectomy with the Nd: YAG laser on tooth 12 to improve the gingival contour. The dental surfaces where the ceramic prosthesis will be cemented were scanned. Then, CAD / CAM technology was used to make the ceramic veneers that were cemented in the same session. Results: The efficacy the Er:YAG laser energy was observed by the decreased of the time to remove all-ceramic materials through ablation of bonding cements, reducing working time by 75% compared to a high-speed turbine. Conclusions: An Er: YAG laser can safely remove lithium disilicate crowns with the settings used in this study. Laser-assisted removal of all ceramic PDFs is a promising treatment protocol. The use of the Nd: YAG (2.0 W power, short 20Hz, 320 µm optical fiber, in contact) laser allowed gingivoplasty to be performed, automatically cauterizing avoiding post-operative bleeding, and facilitating the preparation of ceramic restorations the same day. The use of high-power lasers and the use of accompanying CAD / CAM technology allowed this clinical case to be completed in a single visit without the use of temporary restorations, achieving absolute patient satisfaction. (AU)


Antecedentes: Apresentar os benefícios dos lasers de alta potência (Er: YAG e Nd:YAG) sobre o uso da turbina de alta velocidade para a remoção de restaurações cerâmicas, sem danificar as superfícies dos dentes; sendo um procedimento relativamente mais fácil e rápido evitando o uso de agentes anestésicos, conseguindo fazer o preparo das restaurações de cerâmica e cimentação em uma única sessão; com seguimento de 1 ano. Objetivo: Os benefícios dos lasers sobre a instrumentação mecânica com turbina de alta velocidade para a remoção da coroa abrangem a recuperação eficiente da restauração sem danos às superfícies dos dentes; e um procedimento relativamente mais fácil e rápido sem o uso de agentes anestésicos. Métodos: O laser Er: YAG (sem contato; 3,2-4,0 W, 20 Hz) foi utilizado para remover a prótese de porcelana, seguido de gengivectomia com o laser Nd: YAG no dente 12 para melhorar o contorno gengival. As superfícies dentais onde a prótese de cerâmica será cimentada foram escaneadas. Em seguida, a tecnologia CAD / CAM foi utilizada para confeccionar as facetas de cerâmicas que foram cimentadas na mesma sessão. Resultados: A eficácia da energia do laser Er: YAG foi observada pela diminuição do tempo na remoção dos materiais cerâmicos por meio da ablação dos cimentos de ligação, reduzindo o tempo de trabalho em 75% em relação a uma turbina de alta velocidade. Conclusão: Um laser Er: YAG pode remover com segurança as coroas de dissilicato de lítio com as configurações usadas neste estudo. A remoção assistida por laser de todos os PDFs de cerâmica é um protocolo de tratamento promissor. O uso do laser Nd: YAG (2,0 W potência, curta 20Hz, 320 µm fibra ótica, em contato) permitiu a realização da gengivoplastia, cauterizando automaticamente evitando sangramento pós-operatório e facilitando o preparo das restaurações cerâmicas no mesmo dia. O uso de lasers de alta potência e o uso da tecnologia CAD / CAM que o acompanha permitiram que este caso clínico fosse concluído em uma única visita, sem o uso de restaurações temporárias, alcançando a satisfação absoluta do paciente (AU)


Subject(s)
Humans , Female , Middle Aged , Computer-Aided Design , Dental Materials , Lasers, Solid-State
13.
Chinese Journal of Biotechnology ; (12): 4415-4429, 2021.
Article in Chinese | WPRIM | ID: wpr-921517

ABSTRACT

The zearalenone hydrolase (ZHD101) derived from Clonostachys rosea can effectively degrade the mycotoxin zearalenone (ZEN) present in grain by-products and feed. However, the low thermal stability of ZHD101 hampers its applications. High throughput screening of variants using spectrophotometer is challenging because the reaction of hydrolyzing ZEN does not change absorbance. In this study, we used ZHD101 as a model enzyme to perform computation-aided design followed by experimental verification. By comparing the molecular dynamics simulation trajectories of ZHD101 at different temperatures, 32 flexible sites were selected. 608 saturated mutations were introduced into the 32 flexible sites virtually, from which 12 virtual mutants were screened according to the position specific score and enzyme conformation free energy calculation. Three of the mutants N156F, S194T and T259F showed an increase in thermal melting temperature (ΔTm>4 °C), and their enzyme activities were similar to or even higher than that of the wild type (relative enzyme activity 95.8%, 131.6% and 169.0%, respectively). Molecular dynamics simulation analysis showed that the possible mechanisms leading to the improved thermal stability were NH-π force, salt bridge rearrangement, and hole filling on the molecular surface. The three mutants were combined iteratively, and the combination of N156F/S194T showed the highest thermal stability (ΔTm=6.7 °C). This work demonstrated the feasibility of engineering the flexible region to improve enzyme performance by combining virtual computational mutations with experimental verification.


Subject(s)
Computer-Aided Design , Edible Grain , Enzyme Stability , Hydrolases/metabolism , Hypocreales/enzymology , Protein Engineering , Zearalenone
14.
Article in English | WPRIM | ID: wpr-887749

ABSTRACT

The correct implant site design and placement are the basic clinical techniques that must be known for implant restoration. For a long time, most implants have been placed by free hands, and the choice of site is mostly dependent on the accumulation of long-term experience of the surgeon. The selection of implant site guided by this experience analogy logic is often based on the surgeon's level of experience,which often makes it very easy to produce complications related to the implant restoration of the incorrect site. In contrast, a clinical program using digital guidance and real-time measurable verification has emerged based on the restoration-oriented implantation concept, which marks the formation of an accurate, measurable and verifiable whole-process digital implant prototype. Furthermore, from the perspective of surveying, the numerical requirements that digital implant restoration relies on are actually incomplete to the four elements of measurement, which leading to the doubts about its authenticity. This article will question the numbers in implant restoration, and conduct a preliminary demonstration, and propose a new reliable actual measurement and verification method of the correct location and the numerical requirements of the restoration space and a new clinical program that relies on numbers from the perspective of the evolution of digital restoration, guided implantology and actual measurement technology. And this article further discusses the current mainstream implant restoration technology based on experience analogy which cannot effectively support the whole process of digital implant restoration and provides a new logical cognitive basis for the final realization of the entire process of digital implant restoration.


Subject(s)
Computer-Aided Design , Dental Implantation, Endosseous , Dental Implants , Humans , Prosthodontics
15.
Article in English | WPRIM | ID: wpr-878402

ABSTRACT

Digital technologies use high-precision three-dimensional scanning, intelligence-aided design software, and multi-axis numerical control milling or 3D printing, which can produce restorations with reliable precision and suitable function. However, the development of digital technologies in the field of complete denture restoration has been slow due to the complexity of prosthesis. This review article introduces the current research status and clinical applications of digital complete dentures in prosthodontic clinics and dental laboratories to provide beneficial references to prosthodontists and dental technicians.


Subject(s)
Computer-Aided Design , Denture, Complete , Printing, Three-Dimensional
16.
Braz. dent. sci ; 24(4): 1-7, 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1337660

ABSTRACT

Digital dentistry has gained space in several dental specialties. It is possible to achieve excellent results with the digital workflow, which combines the efficiency of the restorative material with a greater marginal adaptation. This study aimed to report a clinical case through the digital workflow, with a faster and clinically acceptable prosthetic resolution. In this clinical case report, digital workflow allowed a faster and clinically acceptable prosthetic resolution. A 45-year-old female patient reported cementation failure of the prosthetic crown on tooth 14. As it was a vital tooth, the tooth received a total crown preparation. In the same clinical session, the patient's mouth was scanned then a capture software obtained a virtual model. After, the design software planned a digital "diagnostic wax-up", so a leucitic ceramic was chosen for the rehabilitation. The ceramic block was milled and receive stain and glaze, dispensing the prosthesis laboratory. Then, the adhesive cementation was performed with a dual-polymerized resin cement. The final crown had ideal adaptation, with no need for interproximal and occlusal adjustments, with an excellent marginal fit. Within the limitations of this study, this case report showed that the digital workflow allowed a favorable result in a shorter working time, which brought back function and aesthetics, without the need for interproximal and occlusal adjustments. (AU)


A odontologia digital vem ganhando espaço em diversas especialidades odontológicas. Com o fluxo de trabalho digital, é possível alcançar excelentes resultados na reabilitação protética, combinando a eficiência do material restaurador com a adaptação marginal proporcionada pela odontologia digital. O objetivo desse estudo foi relatar um caso clínico através do fluxo de trabalho digital, com uma resolução protética mais rápida e clinicamente aceitável. Paciente do sexo feminino, 45 anos, relatou falha de cimentação da coroa protética do dente 26. Por ser um dente vital, o dente recebeu um preparo de coroa total e os dentes foram escaneados e um software de captura obteve um modelo virtual. Posteriormente, o software de projeto planejou um "enceramento diagnóstico" digital, sendo escolhida uma cerâmica leucítica para a reabilitação. O bloco cerâmico foi fresado e recebeu acabamento, maquiagem e glaze pelo próprio dentista, dispensando um técnico laboratorial de prótese dentária. Em seguida, foi realizada cimentação adesiva definitiva. Este relato de caso mostra que, dentro das limitações desse estudo, o fluxo digital permite um resultado favorável em um menor tempo de trabalho, devolvendo a função e estética, sem necessidade de ajustes interproximais e oclusais (AU)


Subject(s)
Humans , Female , Adult , Dental Prosthesis , Computer-Aided Design , Esthetics, Dental
17.
Pesqui. bras. odontopediatria clín. integr ; 21(supl.1): e210028, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1351224

ABSTRACT

ABSTRACT Objective To evaluate the accuracy of three different digital bracket positioning systems, comparing vertical, mesiodistal and buccolingual accuracy. Material and Methods The same case was sent to Orapix, Insignia, and Orthocad systems and the brackets were bonded to the malocclusion models.Damon 3 MX brackets were used with all systems and the brackets were bonded to the models with the same bonding protocol and materials. The comparison of the position of each single bracket was made with digital photography, and ImageJ software was used to find the length in pixels and then convert it to hundredths of a mm for vertical, mesiodistal and buccolingual displacement, compared to the setup. Results Insignia System reported the average higher vertical displacement (0.28 mm), compared with the other two appliances (0.22-0.23 mm), and showed the lowest average displacement for the mesiodistal and buccolingual positioning (0.14 and 0.07 mm, respectively).However, these slight bracket positioning variations between these bonding systems were not statistically different (p>0.05). Conclusion The three systems analyzed were shown to be accurate in positioning the brackets, and none of them was statistically better.


Subject(s)
Humans , Adult , Orthodontics, Corrective/instrumentation , Orthodontic Brackets , Computer-Aided Design/instrumentation , Data Accuracy , Malocclusion , Analysis of Variance , Statistics, Nonparametric , Photography, Dental/instrumentation , Italy
18.
Rev. Assoc. Med. Bras. (1992) ; 66(11): 1498-1502, Nov. 2020. graf
Article in English | SES-SP, LILACS, SES-SP | ID: biblio-1143638

ABSTRACT

SUMMARY Additive Manufacturing (AM), also known as Rapid Prototyping, is a set of production technologies used in the synthesis of a particular physical object by adding layers to form a part based on data generated by Computer-Aided Design (CAD) systems. These technologies are widely used to quickly create prototypes of products and tools for commercial purposes. Over time, it has also been integrated with other areas, such as healthcare, since these tools have allowed health professionals to assist in diagnoses, surgical planning, and synthesis of orthoses and prostheses for patient rehabilitation. OBJECTIVE: To develop models for the construction of dilators for the treatment of vaginal agenesis. METHODS: Use CAD software and create a physical model using AM to analyze the viability of its production in the elaboration of customized dilators for each patient. RESULTS: The production through AM provides an advantage in the development, facilitating physical alterations just by adjusting the three-dimensional models made by the software in a quick way, thus making the customization process viable. CONCLUSION: The proposed procedure for the manufacture of dilators presented good results and technological feasibility, indicating that it can be a good solution for the production and customization of gynecological devices.


RESUMO A Manufatura Aditiva (MA), também conhecida como Prototipagem Rápida, é um conjunto de tecnologias de produção utilizado na síntese de determinado objeto físico por meio da adição de camadas para formar uma peça com base em dados gerados por sistemas de projeto auxiliado por computador (CAD - Computer Aided Design). Essas tecnologias são muito utilizadas para criação de protótipos de produtos e ferramentas de maneira rápida para fins comerciais. Com o tempo, também se integrou a outras áreas, como a área da saúde, uma vez que essas ferramentas permitiram auxiliar o profissional da saúde em diagnósticos, planejamento cirúrgico e na síntese de órteses e próteses para reabilitação de pacientes. OBJETIVO: Elaborar modelos computadorizados para a construção de dilatadores para tratamento de agenesia vaginal pela impressão 3D. MÉTODO: Utilização de software CAD e criação do modelo físico por meio de MA para análise da viabilidade de sua produção na elaboração de dilatadores customizados para cada paciente. RESULTADOS: A produção por meio de MA atribui uma vantagem ao desenvolvimento, facilitando as alterações físicas apenas ajustando os modelos tridimensionais feitos pelos softwares de maneira rápida, tornando o processo de customização viável. CONCLUSÃO: O procedimento proposto para a fabricação dos dilatadores apresentou bons resultados e viabilidade tecnológica, indicando que pode ser uma boa solução de produção e customização de dispositivos ginecológicos.


Subject(s)
Humans , Prostheses and Implants , Printing, Three-Dimensional , Vagina , Computer-Aided Design
19.
J. oral res. (Impresa) ; 9(5): 414-422, oct. 31, 2020. ilus, tab
Article in English | LILACS | ID: biblio-1179033

ABSTRACT

Purpose: Two important factors in dental prosthesis are making an accurate impression and producing a suitable cast which represents the exact relationship between prepared tooth and oral structures. This study, aimed to investigate the effects of different combinations of impression and pouring materials on marginal and internal adaptation of premolar zirconia crowns. Material and Methods: Forty maxillary premolars were prepared considering round shoulder finish line. The impressions were made either by additional (Panasil) or condensation (Speedex) silicon, and poured by two different types of gypsum materials (Siladent or GC gypsum) (N=10). Zirconia crowns were fabricated using a CAD-CAM system. The crowns were cemented, and the samples were cut in bucco-lingual direction. Marginal and internal gaps were measured by stereomicroscope (×25). Results: The mean marginal gaps for Pansil-Siladent, Panasil-GC, Speedex-Siladent, and Speedex-GC were 141 µm, 143 µm, 131 µm, and 137 µm respectively. The internal gaps were 334 µm, 292 µm, 278 µm, and 257 µm respectively. The independent T-Student test showed no significant differences in average marginal or internal gap among various impression and gypsum materials or their interactions (p>0.05). Two-way ANOVA test showed no significant differences in maximum marginal or internal gap among various impression and gypsum materials and their interactions (p>0.05). Conclusion: The present study revealed no statistically significant difference in marginal/internal gap among crowns prepared using different combinations of impression-pouring materials evaluated.


Introducción: Dos factores importantes en la prótesis dental son hacer una impresión precisa y la producción de un modelo adecuado que represente la relación exacta entre el diente preparado y las estructuras orales. Este estudio, tuvo como objetivo investigar los efectos de diferentes combinaciones de materiales de impresión y vertido sobre la adaptación marginal e interna de coronas de zirconio premolar. Material y Métodos: Se prepararon cuarenta premolares maxilares considerando la línea de meta del hombro redondo. Las impresiones se realizaron con silicio adicional (Panasil) o de condensación (Speedex) y se vertieron con dos tipos diferentes de materiales de yeso (yeso Siladent o GC) (N = 10). Las coronas de zirconio se fabricaron utilizando el sistema CAD-CAM. Las coronas se cementaron y las muestras se cortaron en dirección buco-lingual. La brecha marginal e interna se midió con estereomicroscopio (×25). Resultados: Las brechas marginales medias para Pansil-Siladent, Panasil-GC, Speedex-Siladent y Speedex-GC fueron de 141µm, 143µm, 131µm y 137µm, respectivamente. Las brechas internas fueron 334µm, 292µm, 278µm y 257µm, respectivamente. La prueba de T-Student independiente no mostró diferencias significativas en la brecha marginal o interna promedio entre varios materiales de impresión y yeso o sus interacciones (p>0.05). La prueba ANOVA bidireccional no mostró diferencias significativas en el espacio marginal o interno máximo entre varios materiales de yeso y de impresión y sus interacciones (p>0.05). Conclusión: El presente estudio no reveló diferencias estadísticamente significativas en la brecha marginal/interna entre las coronas preparadas con diferentes combinaciones de materiales de impresión y vertido evaluados.


Subject(s)
Humans , Dental Prosthesis/methods , Crowns , Dental Impression Materials , Zirconium/chemistry , Bicuspid , Calcium Sulfate , Computer-Aided Design , Dental Cements , Dental Restoration, Permanent
20.
Rev. Eugenio Espejo ; 14(1): 28-40, 20200615.
Article in Spanish | LILACS | ID: biblio-1117185

ABSTRACT

El objetivo de esta investigación fue analizar los ángulos de convergencia en preparaciones dentarias para coronas realizadas en tipodontos, por estudiantes de décimo semestre de Odontología Unach. Las preparaciones dentales para coronas poseen características de retención y resistencia, principios fundamentales que ofrecen éxito y longevidad de la corona definitiva. Varios investigadores a nivel mundial han desarrollado diversos métodos para evaluar los ángulos de convergencia de las preparaciones extracoronarias; sin embargo, en nuestro medio, no existen estudios acerca de la medición de estos ángulos. Esta investigación fue de carácter experimental, transversal y observacional, se obtuvieron 32 preparaciones dentarias para coronas de recubrimiento completo, cada estudiante tuvo 60 minutos para tallar dos preparaciones dentarias en simuladores clínicos. Los tipodontos fueron escaneados y digitalizados mediante el escáner CAD-CAM Ceramill Database versión 1.0 año 2010 del Laboratorio "BrothersDent" para producir imágenes tridimensionales. El software iTero midió los ángulos vestíbulo-lingual (VL) y mesio-distal (MD) de cada preparación. Los ángulos más pequeño y más grande observados fueron 3.1° y 102.5° para molares mandibulares. El promedio del ángulo VL para dientes anteriores fue 40,38 ±4,38° en varones y 36,97 ±3,95° en mujeres y el promedio del ángulo MD fue 44,68 ±5,51° en varones y 40,08 ±3,99° en mujeres. Para dientes posteriores el promedio VL fue 27,46 ±7,82° en varones y 40,98 ±4,63° en mujeres; y el promedio del ángulo MD fue 40,73 ±5,95° en varones y 50,62 ±7,00° en mujeres. En conclusión, los ángulos de convergencia logrados por estudiantes fueron mayores que los ideales recomendados según Shillingburg.


This research aimed to analyze the angles of convergence in dental preparations for crowns performed on typodont, by 10th semester students of school of dentistry, UNACH. Dental preparations for crowns have retention and resistance characteristics, fundamental principles that offer success and longevity of the final crown. Various researchers worldwide have developed various methods to evaluate the convergence angles of extra coronary preparations; however, in our context, there are no studies on the measurement of these angles. This research was experimental, cross-sectional and observational, 32 dental preparations were obtained for fully covered crowns, each student had 60 minutes to carve two dental preparations in clinical simulators. The typodonts were scanned and digitized using the scanner CAD-CAM Ceramill Database version 1.0 - 2010 of "BrothersDent" Laboratory in order to produce three-dimensional images. The iTero software measured the vestibule-lingual (VL) and mesio-distal (MD) angles of each preparation. The smallest and largest angles observed were 3.1 ° and 102.5 ° for mandibular molars. The mean VL angle for anterior teeth was 40.38 ± 4.38 ° in males and 36.97 ± 3.95 ° in females, and the mean MD angle was 44.68 ± 5.51 ° in males and 40, 08 ± 3.99 ° in women. For posterior teeth the average VL was 27.46 ± 7.82 ° in men and 40.98 ± 4.63 ° in women; and the mean MD angle was 40.73 ± 5.95 ° in men and 50.62 ± 7.00 ° in women. In conclusion, the convergence angles achieved by students were greater than the recommended ideals according to Shillingburg.


Subject(s)
Humans , Male , Female , Adult , Computer-Aided Design , Crowns , Molar , Research , Students, Dental , Tooth
SELECTION OF CITATIONS
SEARCH DETAIL