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1.
Rev. Flum. Odontol. (Online) ; 1(66): 144-154, jan-abr.2025. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-1570750

RESUMO

O avanço da tecnologia de digitalização de imagens e desenvolvimento de dispositivos de fresagem possibilitaram a otimização de diversos processos na Odontologia. O emprego do escaneamento intraoral e do sistema CAD-CAM (CAD - Computer Aided Design; CAM - Computer Aided Manufacturing) aprimorou a realização de reabilitações protéticas, permitindo a obtenção de peças de alta qualidade em tempo reduzido. O objetivo deste trabalho é relatar um caso de reabilitação de um incisivo central inferior a partir de escaneamento intraoral, com scanner Omnicam (DentsplySirona Charlotte, NC, EUA) e aplicação do sistema CAD-CAM.


The advancement of image digitization technology and the development of milling devices have made it possible to optimize various processes in Dentistry. The use of intraoral scanning and the CAD-CAM system (CAD - Computer Aided Design; CAM - Computer Aided Manufacturing) has improved the performance of prosthetic rehabilitations, allowing the obtaining of high quality parts in a reduced time. The objective of this work is to report a case of rehabilitation of a lower central incisor using intraoral scanning, with an Omnicam scanner (Dentsply Sirona) and application of the CAD-CAM system.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Reabilitação , Desenho Assistido por Computador , Odontologia , Modelos Anatômicos
2.
Am J Dent ; 37(5): 263-267, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39321107

RESUMO

PURPOSE: To evaluate the marginal and internal misfit of fixed partial denture zirconia frameworks developed from conventional impression and intraoral scanning, before and after being subjected to the thermal cycle of the covering ceramic. METHODS: A three-elements fixed partial denture was prepared, molded, and poured with polyurethane. Group CI (n= 7) was impressed by the conventional technique with polyvinyl siloxane material, and the plaster models scanned on the inEosX5 bench scanner. Group DI (n=07) was scanned using the CEREC Bluecam intraoral scanner. The models and images obtained were sent to the laboratory and the frameworks were made using zirconia blocks. After this, they were subjected to the ceramic thermal cycle, simulating the ceramic application. Marginal and internal misfits of the frameworks were measured before (T1) and after (T2) thermal cycle simulation using the replica technique in an optical microscope. Statistical analysis was performed using the mixed effects of linear model tests and comparisons. RESULTS: There were no statistical differences for axial misfit. Significant differences were found between the groups for occlusal, vertical, horizontal, and absolute misfit, where group CI had higher values than group DI (P< 0.001). At the time, there was a statistical difference only in the absolute misfit, where T1 had lower values than T2. The misfit in group CI was greater than in group DI; however, the average misfit values found are low and considered clinically acceptable. CLINICAL SIGNIFICANCE: Knowing marginal and internal misfit is an important step to consolidating digital impressions in fixed partial dentures, implying a secure use of this technique.


Assuntos
Desenho Assistido por Computador , Técnica de Moldagem Odontológica , Adaptação Marginal Dentária , Planejamento de Dentadura , Prótese Parcial Fixa , Zircônio , Zircônio/química , Planejamento de Dentadura/métodos , Humanos , Siloxanas/química , Materiais para Moldagem Odontológica/química , Polivinil/química , Modelos Dentários
3.
Molecules ; 29(17)2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39275072

RESUMO

Cruzipain (CZP), the major cysteine protease present in T. cruzi, the ethiological agent of Chagas disease, has attracted particular attention as a therapeutic target for the development of targeted covalent inhibitors (TCI). The vast chemical space associated with the enormous molecular diversity feasible to explore by means of modern synthetic approaches allows the design of CZP inhibitors capable of exhibiting not only an efficient enzyme inhibition but also an adequate translation to anti-T. cruzi activity. In this work, a computer-aided design strategy was developed to combinatorially construct and screen large libraries of 1,4-disubstituted 1,2,3-triazole analogues, further identifying a selected set of candidates for advancement towards synthetic and biological activity evaluation stages. In this way, a virtual molecular library comprising more than 75 thousand diverse and synthetically feasible analogues was studied by means of molecular docking and molecular dynamic simulations in the search of potential TCI of CZP, guiding the synthetic efforts towards a subset of 48 candidates. These were synthesized by applying a Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) centered synthetic scheme, resulting in moderate to good yields and leading to the identification of 12 hits selectively inhibiting CZP activity with IC50 in the low micromolar range. Furthermore, four triazole derivatives showed good anti-T. cruzi inhibition when studied at 50 µM; and Ald-6 excelled for its high antitrypanocidal activity and low cytotoxicity, exhibiting complete in vitro biological activity translation from CZP to T. cruzi. Overall, not only Ald-6 merits further advancement to preclinical in vivo studies, but these findings also shed light on a valuable chemical space where molecular diversity might be explored in the search for efficient triazole-based antichagasic agents.


Assuntos
Cisteína Endopeptidases , Simulação de Acoplamento Molecular , Proteínas de Protozoários , Triazóis , Trypanosoma cruzi , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Cisteína Endopeptidases/química , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/química , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/enzimologia , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Cisteína Proteinase/síntese química , Simulação de Dinâmica Molecular , Relação Estrutura-Atividade , Desenho Assistido por Computador , Desenho de Fármacos , Humanos , Estrutura Molecular , Tripanossomicidas/farmacologia , Tripanossomicidas/química , Tripanossomicidas/síntese química , Doença de Chagas/tratamento farmacológico
4.
Oper Dent ; 49(5): 531-539, 2024 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-39187958

RESUMO

Although at-home bleaching can recover the optical properties of stained CAD-CAM monolithic materials, little is known about its impact on their surface and mechanical properties, especially when successive sessions are performed. This study evaluated the effect of successive at-home bleaching sessions on the microhardness, roughness, topography, biaxial flexural strength (BFS), and reliability of CAD-CAM monolithic materials. Disks from Lava Ultimate (LU), Vita Enamic (VE), and IPS Empress CAD (EMP) were fabricated and submitted to up to three bleaching sessions. At-home bleaching was performed with 10% carbamide peroxide, and each session consisted of one application for 10 hours/day for 14 days. The analyses of the aforementioned parameters were assessed before and after the first, second, and third bleaching sessions, except for BFS, which was evaluated at baseline and after the third session. The Weibull modulus was calculated from the BFS data. The microhardness of the three materials as well as the roughness of LU were not affected by the sessions, whereas the roughness of VE and EMP increased from the second session. All materials displayed topographic changes, which became more pronounced with the increase in the number of sessions. Although bleaching decreased the BFS of the materials, it did not adversely affect their reliability. Successive at-home bleaching sessions with the protocol used in the present study cannot be considered a safe procedure for the materials evaluated.


Assuntos
Peróxido de Carbamida , Desenho Assistido por Computador , Resistência à Flexão , Teste de Materiais , Propriedades de Superfície , Clareamento Dental , Clareamento Dental/métodos , Reprodutibilidade dos Testes , Clareadores Dentários , Materiais Dentários/química , Peróxidos , Humanos , Dureza , Porcelana Dentária/química , Cerâmica
5.
Biomed Mater Eng ; 35(5): 415-423, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39121111

RESUMO

BACKGROUND: Tissue engineering seeks to improve, maintain, or replace the biological functions of damaged organs or tissues with biological substitutes such as the development of scaffolds. In the case of bone tissue, they must have excellent mechanical properties like native bone. OBJECTIVE: In this work, three geometric models were designed for scaffolds with different structure lattices and porosity that could be biomechanically suitable and support cell growth for trabecular bone replacement applications in tissue engineering and regenerative medicine to the proximal femur area. METHODS: Geometries were designed using computer-aided design (CAD) software and evaluated using finite element analysis in compression tests. Three loads were considered according to the daily activity: 1177 N for slow walking, 2060 N for fast walking, and 245.25 N for a person in a bipedal position. All these loads for an adult weight of 75 kg. For each of them, three biomaterials were assigned: two polymers (poly-glycolic acid (PGA) and poly-lactic acid (PLA)) and one mineral (hydroxyapatite (HA)). 54 tests were performed: 27 for each of the tests. RESULTS: The results showed Young's modulus (E) between 1 and 4 GPa. CONCLUSION: If the resultant E is in the range of 0.1 to 5 GPa, the biomaterial is considered an appropriate alternative for the trabecular bone which is the main component of the proximal bone. However, for the models applied in this study, the best option is the poly-lactic acid which will allow absorbing the acting loads.


Assuntos
Desenho Assistido por Computador , Análise de Elementos Finitos , Engenharia Tecidual , Alicerces Teciduais , Alicerces Teciduais/química , Humanos , Engenharia Tecidual/métodos , Durapatita/química , Módulo de Elasticidade , Bioimpressão/métodos , Poliésteres/química , Porosidade , Simulação por Computador , Materiais Biocompatíveis/química , Substitutos Ósseos/química , Ácido Poliglicólico/química , Impressão Tridimensional , Teste de Materiais , Osso e Ossos
6.
Rev. ADM ; 81(4): 220-224, jul.-ago. 2024. ilus
Artigo em Espanhol | LILACS | ID: biblio-1572789

RESUMO

Introducción: el alargamiento de corona relacionado con la estética tiene como objetivo revelar una longitud adecuada de la corona y disminuir la exposición gingival. El procedimiento incluye gingivectomía y alveolectomía para restablecer el tejido gingival supracrestal requerido protésicamente según la dimensión fisiológica. Mediante un escaneo intraoral del maxilar, mandíbula y posición intercuspídea máxima y utilizando un software especializado, se diseña de manera digital la forma de los dientes y el contorno gingival. Este diseño genera una imagen de la restauración estética deseada para el prostodoncista y periodoncista. La fabricación física del diseño es asistida por computadora (CAD-CAM), creando una guía quirúrgica de resina acrílica moldeada al vacío para determinar la longitud de la corona clínica requerida en la cirugía. Objetivo: el caso interdisciplinario presentado describe una técnica innovadora empleando el flujo digital mediante un software que, a partir de un escaneo oral, diseña de manera digital un Mock-Up utilizado como guía para la cirugía periodontal. Presentación del caso: acude a clínica de la Maestría en Periodoncia de la Universidad Autónoma de Coahuila (UAdeC) paciente de 52 años, ASA I, para una cirugía periodontal con fines estéticos. Se procedió a la cirugía, colocando el Mock-Up en la región anterosuperior como guía para la gingivectomía. Luego, se realizó el levantamiento de colgajo antes de la alveolectomía, tomando en cuenta la longitud del tejido gingival supracrestal. Por último, se suturaron los tejidos blandos con técnica de colchonero horizontal. Resultados: siete días después, se retiran los puntos apreciando una cicatrización correcta y uniforme de los tejidos. Conclusiones: este abordaje digital ofrece una reducción significativa del tiempo quirúrgico, además de una estética satisfactoria y una precisa arquitectura gingival (AU)


Introduction: crown lengthening for aesthetic purposes aims to reveal an adequate crown length and reduce gingival exposure. The procedure includes gingivectomy and alveolectomy to restore the prosthetically required supracrestal gingival tissue according to physiological dimensions. Through an intraoral scan of the maxilla, mandible, and maximum intercuspidal position, and using specialized software, the shape of the teeth and the gingival contour are digitally designed. This design generates an image of the desired aesthetic restoration for the prosthodontist and periodontist. The physical fabrication of the design is computer-assisted (CAD-CAM), creating a vacuum-formed acrylic resin surgical guide to determine the clinical crown length required in surgery. Objective: the presented interdisciplinary case describes an innovative technique using digital workflow through software that, from an oral scan, digitally designs a Mock-Up used as a guide for periodontal surgery. Case presentation: a 52-year-old ASA I patient attended the Periodontics Master's clinic at Universidad Autónoma de Coahuila (UAdeC) for periodontal surgery with aesthetic purposes. The surgery was performed by placing the Mock-Up in the anterosuperior region as a guide for gingivectomy. Then, a flap was raised before the alveolectomy, considering the length of the supracrestal gingival tissue. Finally, the soft tissues were sutured with a horizontal mattress suture technique. Results: seven days later, the sutures were removed, showing correct and uniform tissue healing. Conclusions: this digital approach offers a significant reduction in surgical time, in addition to satisfactory esthetics and precise gingival architecture (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Processamento de Imagem Assistida por Computador/métodos , Aumento da Coroa Clínica , Desenho Assistido por Computador , Imageamento Tridimensional/métodos , Estética Dentária , Faculdades de Odontologia , Gengivectomia/métodos , México
7.
J Esthet Restor Dent ; 36(10): 1444-1451, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38963682

RESUMO

OBJECTIVE: To evaluate the effect of the deterioration of computer aided design/computer aided manufacturing (CAD/CAM) burs during zirconia milling, on surface roughness, contact angle, and fibroblast viability. MATERIALS AND METHODS: Ceramic blocks were milled and 75 ceramic disks (8 × 1.5 mm) made and allocated into three groups (n = 25): G1-brand new 2L and 1L burs, G2-2L bur at the end of lifetime and brand new 1L bur and G3-both burs at the end of their lifetimes. Roughness (Ra, Rq, and Rz) was evaluated using a 3D optical profilometer, the contact angle by the sessile drop method and the cell viability of the mouse NIH/3T3 fibroblast, using the Alamar Blue assay at intervals of 24, 48, and 72 h (ISO 10993-5). Data were analyzed by one-way ANOVA and Kruskal-Wallis tests (p ≤ 0.05). RESULTS: Roughness increased as the burs deteriorated and G3 (0.27 ± 0.04) presented a higher value for Ra (p < 0.001). The highest contact angle was observed in G3 (86.2 ± 2.66) when compared with G1 (63.7 ± 12.49) and G2 (75.3 ± 6.36) (p < 0.001). Alamar Blue indicated an increase in cell proliferation, with no significant differences among the groups at 24 and 72 h (p > 0.05). CONCLUSIONS: The deterioration of the burs increased the surface roughness and decreased the wettability, but did not interfere in cell viability and proliferation. CLINICAL SIGNIFICANCE: The use of custom zirconia abutments represents an effective strategy for single crowns restorations. Our findings suggest that these abutments can be efficiently milled using CAD/CAM burs within their recommended lifetime.


Assuntos
Desenho Assistido por Computador , Propriedades de Superfície , Zircônio , Zircônio/química , Camundongos , Animais , Dente Suporte , Materiais Biocompatíveis , Células NIH 3T3 , Teste de Materiais
8.
Braz Oral Res ; 38: e063, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39016369

RESUMO

Computer-aided manufacturing (CAM) technology allows the use of different manufacturing techniques. This in vitro study aimed to evaluate the marginal fit of temporary restorations manufactured using conventional chairside methods, milling, and three-dimensional printing. Fifteen 3-element temporary restorations specimens were produced and categorized into three groups: non-digital, obtained using the conventional chairside method (GC); milled (GM); and three-dimensionally printed (GP). Marginal fit was assessed using scanning electron microscopy (SEM) performed under two conditions: one with only the central screw tightened, and the other with all three screws tightened. Horizontal misfit values were categorized as over-, equal-, and under-extended and qualitatively analyzed. Statistical analysis was performed using the Tukey-Kramer test (α=0.05). In the vertical assessment, three-dimensionally printed restorations demonstrated greater misfit than restorations obtained by milling and the conventional chairside method (P<0.05). In the horizontal assessment, the misfit in the GP group was significantly higher than that in the GM and GC groups. Restorations obtained using the conventional chairside method and milled provisional restorations showed more favorable results than three-dimensionally printed restorations.


Assuntos
Desenho Assistido por Computador , Adaptação Marginal Dentária , Planejamento de Prótese Dentária , Restauração Dentária Temporária , Teste de Materiais , Microscopia Eletrônica de Varredura , Impressão Tridimensional , Propriedades de Superfície , Restauração Dentária Temporária/métodos , Planejamento de Prótese Dentária/métodos , Reprodutibilidade dos Testes , Valores de Referência , Estatísticas não Paramétricas , Humanos
9.
Radiat Prot Dosimetry ; 200(13): 1294-1305, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39007516

RESUMO

Some of the difficulties in numerical modeling of wireless communication devices for dosimetric evaluations arise from, e.g. incomplete documentation available for the numerical model, such as missing information on dielectric materials or the antenna matching circuitry. This study investigates the impact of these difficulties on the dosimetric results, such as the peak spatial average specific absorption rate at 900 and 1800 MHz and the peak spatial average power density at 28 GHz. The impact of dielectric losses, detuning, and mesh resolution is quantified using different generic and Computer Aided Design (CAD) based models of wireless transmitters. The findings show that the uncertainties of the numerical results due to detuning and mesh resolution can be reduced by normalization to the antenna feedpoint power instead of the feedpoint current. Uncertainties due to variations in dielectric losses can largely be compensated by normalization to the radiated power.


Assuntos
Tecnologia sem Fio , Incerteza , Simulação por Computador , Modelos Teóricos , Humanos , Desenho Assistido por Computador , Radiometria/métodos , Desenho de Equipamento , Ondas de Rádio
10.
J Mol Model ; 30(8): 255, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970658

RESUMO

CONTEXT: Although quantum mechanical calculations have proven effective in accurately predicting UV absorption and assessing the antioxidant potential of compounds, the utilization of computer-aided drug design (CADD) to support sustainable synthesis research of new sunscreen active ingredients remains an area with limited exploration. Furthermore, there are ongoing concerns about the safety and effectiveness of existing sunscreens. Therefore, it remains crucial to investigate photoprotection mechanisms and develop enhanced strategies for mitigating the harmful effects of UVR exposure, improving both the safety and efficacy of sunscreen products. A previous study conducted synthesis research on eight novel hybrid compounds (I-VIII) for use in sunscreen products by molecular hybridization of trans-resveratrol (RESV), avobenzone (AVO), and octinoxate (OMC). Herein, time-dependent density functional theory (TD-DFT) calculations performed in the gas phase on the isolated hybrid compounds (I-VIII) proved to reproduce the experimental UV absorption. Resveratrol-avobenzone structure-based hybrids (I-IV) present absorption maxima in the UVB range with slight differences between them, while resveratrol-OMC structure-based hybrids (V-VIII) showed main absorption in the UVA range. Among RESV-OMC hybrids, compounds V and VI exhibited higher UV absorption intensity, and compound VIII stood out for its broad-spectrum coverage in our simulations. Furthermore, both in silico and in vitro analyses revealed that compounds VII and VIII exhibited the highest antioxidant activity, with compound I emerging as the most reactive antioxidant within RESV-AVO hybrids. The study suggests a preference for the hydrogen atom transfer (HAT) mechanism over single-electron transfer followed by proton transfer (SET-PT) in the gas phase. With a strong focus on sustainability, this approach reduces costs and minimizes effluent production in synthesis research, promoting the eco-friendly development of new sunscreen active ingredients. METHODS: The SPARTAN'20 program was utilized for the geometry optimization and energy calculations of all compounds. Conformer distribution analysis was performed using the Merck molecular force field 94 (MMFF94), and geometry optimization was carried out using the parametric method 6 (PM6) followed by density functional theory (DFT/B3LYP/6-31G(d)). The antioxidant behavior of the hybrid compounds (I-VIII) was determined using the highest occupied molecular orbital (εHOMO) and the lowest unoccupied molecular orbital (εLUMO) energies, as well as the bond dissociation enthalpy (BDE), ionization potential (IP), and proton dissociation enthalpy (PDE) values, all calculated at the same level of structural optimization. TD-DFT study is carried out to calculate the excitation energy using the B3LYP functional with the 6-31G(d) basis set. The calculated transitions were convoluted with a Gaussian profile using the Gabedit program.


Assuntos
Antioxidantes , Desenho Assistido por Computador , Desenho de Fármacos , Resveratrol , Protetores Solares , Raios Ultravioleta , Protetores Solares/química , Antioxidantes/química , Antioxidantes/farmacologia , Resveratrol/química , Propiofenonas/química , Teoria da Densidade Funcional , Estilbenos/química , Estilbenos/farmacologia , Modelos Moleculares , Teoria Quântica , Estrutura Molecular
11.
Dent Med Probl ; 61(3): 417-426, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38888224

RESUMO

Severe tooth wear is related to substantial loss of tooth structure, with dentin exposure and significant loss (≥1/3) of the clinical crown. The objective of this systematic review was to summarize and analyze the scientific evidence regarding the mechanical performance of computer-aided design/computer-aided manufacturing (CAD/CAM) composite resin and CAD/CAM lithium disilicate ceramic occlusal veneers, in terms of fatigue and fracture resistance, on severely worn posterior teeth. Currently, occlusal veneers are an alternative for treating worn posterior teeth. Although scientific evidence demonstrates the good performance of lithium disilicate occlusal veneers, there are less brittle materials with a modulus of elasticity more similar to dentin than ceramics, such as resin CAD/CAM blocks. Therefore, it is important to identify which type of material is best for restoring teeth with occlusal wear defects and which material can provide better clinical performance. This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive search of the PubMed, Embase, Web of Science, Scopus, Cochrane, OpenGrey, Redalyc, DSpace, and Grey Literature Report databases was conducted and supplemented by a manual search, with no time or language limitations, until January 2022. We aimed to identify studies evaluating the fatigue and fracture resistance of CAD/CAM composite resin and ceramic occlusal veneers. The quality of the full-text articles was evaluated according to the modified Consolidated Standards of Reporting Trials (CONSORT) criteria for in vitro studies, and 400 articles were initially identified. After removing duplicates and applying the selection criteria, 6 studies were included in the review. The results demonstrated that the mechanical performance of CAD/CAM composite resin occlusal veneers is comparable to that of CAD/CAM lithium disilicate occlusal veneers in terms of fatigue and fracture resistance.


Assuntos
Cerâmica , Resinas Compostas , Desenho Assistido por Computador , Facetas Dentárias , Humanos , Porcelana Dentária , Falha de Restauração Dentária , Desgaste dos Dentes/etiologia , Desgaste dos Dentes/terapia
12.
Clin Oral Investig ; 28(7): 402, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940942

RESUMO

OBJECTIVES: Evaluate the efficacy of denture cleaners on the adhesion of Candida albicans and their effects on the surface, optical, and mechanical properties of resins for conventional, milled, and 3D-printed denture bases. MATERIALS AND METHODS: A total of 240 resin samples were made, 120 for testing Candida albicans adhesion, optical stabilities (ΔE00), roughness (Ra), hydrophilicity (°), surface free energy (Owens-Wendt) and 120 samples for testing Candida albicans adhesion, surface microhardness (Knoop), flexural strength and modulus of elasticity in a three-point test, in which they were divided into 3 groups of denture resin (n = 40) and subdivided into 5 cleaners of dentures (n = 8). Data were evaluated by two-way ANOVA and Tukey's test for multiple comparisons (α = 0.05). RESULTS: Denture cleaners with an alkaline solution and dilute acid composition were those that showed the greatest effectiveness in reducing Candida albicans (P < 0.001), however 1% NaOCl significantly affected the properties of the resins (P < 0.05). Denture 3D-printed showed that the surface microhardness was significantly lower for all cleansers (P < 0.05). CONCLUSIONS: Listerine demonstrated superior efficacy in reducing Candida albicans with minimal effect on denture properties, whereas 1% NaOCl had a significant negative impact on the properties. The mechanical properties were significantly lower in 3D-printed resin than in other resins for all denture cleansers. CLINICAL RELEVANCE: Denture base materials are being sold to adapt to the CAD/CAM system, increasing the number of users of dentures manufactured with this system. Despite this, there is little investigation into denture cleaners regarding the adhesion capacity of microorganisms and the optical, surface and mechanical properties of dentures, thus requiring further investigation.


Assuntos
Candida albicans , Desenho Assistido por Computador , Bases de Dentadura , Higienizadores de Dentadura , Teste de Materiais , Impressão Tridimensional , Propriedades de Superfície , Candida albicans/efeitos dos fármacos , Bases de Dentadura/microbiologia , Higienizadores de Dentadura/farmacologia , Dureza , Resistência à Flexão , Materiais Dentários/química
13.
J Oral Implantol ; 50(4): 431-434, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38826061

RESUMO

The purpose of the present study was to evaluate the Morse effect of different internal tapered implant-abutment connections (ITCs) using a pullout test. Implants with different ITCs were selected: Short (Bicon, USA), G1; Novo Colosso (Medens, Brazil), G2; Epkut (SIN, Brazil), G3; Strong SW (SIN, Brazil), G4; Flash (Conexão, Brazil), G5 and Bone Level (Straumann, Switzerland), G6. The respective computer-aided design (CAD) files were loaded into the analysis software to measure each ITC's taper angle and implant-abutment contact area. Six implants from each group were embedded in acrylic resin blocks, and the respective universal abutments were fixed using a mallet (G1) or by applying 20 Ncm of torque (G2 to G6). After 10 minutes, each abutment's retention screw was removed, and the force necessary for abutment rupture was recorded using a universal testing machine at a crosshead speed of 0.5 mm/min. The groups were compared using a one-way analysis of variance and Tukey's test. Spearman's correlation was used to check the correlation of the taper angle and contacting area with the pullout strength. G1, a no-screw abutment with a 3° taper, and G2, a 10° tapered abutment tightened by 20 Ncm, presented the highest pullout strength (P < .05). The increased taper angle of G4, compared to G3, reduced the Morse effect despite their similar implant-abutment contacting areas (P < .05). The G5 and G6 abutments loosened after screw removal and did not exhibit pullout resistance. The closer the tapered angle (r = -.958) and the higher the implant-abutment contact area (r = .880), the higher the pullout strength (P < .001). Within the limits of this study, the Morse effect is different among tapered implant-abutment connections. The closer the tapered angle and the higher the interface area, the higher the Morse effect between the abutment and the implant.


Assuntos
Desenho Assistido por Computador , Dente Suporte , Projeto do Implante Dentário-Pivô , Análise do Estresse Dentário , Implantes Dentários , Torque , Humanos , Teste de Materiais
14.
Prim Dent J ; 13(2): 53-57, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38888075

RESUMO

A technique is outlined for utilising a polymeric composite reinforced with glass fibres in a three-dimensional mesh as a post-core in aesthetic cases. The clinical procedure involves obtaining an impression of the root canal space, scanning the definitive cast, and milling a fibre-reinforced composite post-core. Subsequently, the intra-radicular post-core is cemented using an adhesive resin cement. The use of custom-made computer-aided design-computer-aided manufacturing (CAD-CAM) fibre-reinforced composite post-core facilitates repairability, provides better adaptation to the root canal space, avoids uneven cement thickness, ensures chemical adhesion to resin cement, and promotes favourable aesthetics when combined with all-ceramic crowns.


Assuntos
Resinas Compostas , Desenho Assistido por Computador , Planejamento de Prótese Dentária , Vidro , Técnica para Retentor Intrarradicular , Humanos , Resinas Compostas/química , Vidro/química , Cimentos de Resina/química , Coroas , Estética Dentária , Retenção em Prótese Dentária , Materiais Dentários/química , Cimentação
15.
Clin Oral Investig ; 28(6): 320, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38750145

RESUMO

OBJECTIVES: The purpose of this scoping review was to identify different methods employed for recording the maxillomandibular relationship (MMR) for computer-aided designed and manufactured (CAD-CAM) complete dentures (CDs). MATERIALS AND METHODS: This scoping review followed the PRISMA-ScR guidelines and was developed according to Arksey and O'Malley and The Joanna Briggs Institute protocol. The methods were registered on the Open Science Framework (< osf.io/rf4xm> ). The focus question was: "What are the different techniques for recording the maxillomandibular relationship in the digital workflow used in CECDs?" Two investigators searched 3 online databases [MEDLINE (PubMed), Scopus, and Science Direct] independently. The inclusion criteria were clinical studies and reviews that assessed techniques for recording MMR using digital workflow for manufacturing of CECDs. A descriptive analysis was performed considering the study design, manufacturing system, clinical steps, and tools for the determination of MMR, and the difficulty level of procedures. RESULTS: 4779 articles were identified in the electronic search and 10 studies were included for data analysis. The review identified 4 commercially available CAD-CAM denture systems and 3 innovative methods suitable for abbreviating the number of appointments (2 to 4 visits). The trial denture is inherent to the procedure for the Baltic System and 3 innovative techniques. Three techniques (2 innovative and WholeYouNexteeth) demonstrated lower difficulty levels for performing the clinical procedures, regardless of the professional skills. CONCLUSIONS: The commercially available and innovative techniques for the recording of MMR may provide predictability of the treatment. The techniques are effective, however, rely on the learning curve and the patient's clinical condition. CLINICAL RELEVANCE: Recording of the maxillomandibular relationship is paramount for the manufacturing and functionality of complete dentures. Clinicians should be aware of the different tools and techniques described for registering the jaw relationship.


Assuntos
Desenho Assistido por Computador , Planejamento de Dentadura , Prótese Total , Humanos , Planejamento de Dentadura/métodos , Registro da Relação Maxilomandibular/métodos
16.
BMJ Case Rep ; 17(5)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749520

RESUMO

This case report focuses on the replacement of ceramic laminate veneers with suboptimal marginal fit and design, employing a digital workflow and CAD-CAM technology. The patient, a woman in her 30s, expressed concerns about the appearance and hygiene challenges of her existing veneers. A comprehensive assessment, including clinical examination, facial photographs and intraoral scanning, was conducted. Utilising CAD software, facial photographs and 3D models merged to create a digital wax-up, crucial in designing suitable veneers and addressing issues like overcontouring and a poor emergence profile. Following the removal of old veneers, a mock-up was performed and approved. Preparations ensured space for restorations with well-defined margins. The final restorations, milled with Leucite-reinforced vitreous ceramic, were cemented. At the 1 year follow-up, improved aesthetics, gingival health and functional restorations were observed. This report highlights the efficacy of digital workflows in achieving consistent and aesthetically pleasing outcomes in ceramic laminate veneer replacement.


Assuntos
Cerâmica , Desenho Assistido por Computador , Facetas Dentárias , Fluxo de Trabalho , Humanos , Feminino , Adulto , Estética Dentária , Planejamento de Prótese Dentária/métodos , Porcelana Dentária
17.
J Dent ; 147: 105089, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38772449

RESUMO

OBJECTIVE: The purpose of this systematic review and meta-analysis was to evaluate the accuracy (trueness and precision), marginal and internal adaptation, and margin quality of zirconia crowns made by additive manufacturing compared to subtractive manufacturing technology. METHODS: The investigation adhered to the PRISMA-ScR guidelines for systematic reviews and was registered at the Prospero database (n°CRD42023452927). Four electronic databases, including PubMed, Scopus, Embase, and Web of Science and manual search was conducted to find relevant studies published until September 2023. In vitro studies that assessed the trueness and precision, marginal and internal adaptation, and margin quality of printed crowns compared to milled ones were included. Studies on crowns over implants, pontics, temporary restorations, laminates, or exclusively experimental materials were excluded. RESULTS: A total of 9 studies were included in the descriptive reporting and 7 for meta-analysis. The global meta-analysis of the trueness (P<0.74,I2=90 %) and the margin quality (P<0.61,I2=0 %) indicated no significant difference between the root mean square of printed and milled zirconia crowns. The subgroup analysis for the printing system showed a significant effect (P<0.01). The meta-analysis of the crown areas indicated no significant difference in most of the areas, except for the marginal (favoring milled crowns) and axial (favoring printed crowns) areas. For precision and adaptation, both methods showed a clinically acceptable level. CONCLUSIONS: Additive manufacturing technology produces crowns with trueness and margin quality comparable to subtractive manufacturing. Both techniques have demonstrated the ability to produce crowns with precision levels, internal discrepancy, and marginal fit within clinically acceptable limits. CLINICAL SIGNIFICANCE: 3D printing emerges as a promising and potentially applicable alternative method for manufacturing zirconia crowns, as it shows trueness and margin quality comparable to restorations produced by the subtractive method.


Assuntos
Coroas , Adaptação Marginal Dentária , Planejamento de Prótese Dentária , Impressão Tridimensional , Zircônio , Zircônio/química , Humanos , Planejamento de Prótese Dentária/métodos , Desenho Assistido por Computador , Materiais Dentários/química
18.
J Dent ; 147: 105100, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38797488

RESUMO

OBJECTIVE: This scoping review aimed to map the literature on the utilization of intraoral scanners (IOS) in fabricating post and core restorations. DATA: The study protocol is available at https://osf.io/ja9xh/. This scoping review followed Joanna Briggs Institute guidelines, and reporting was based on the checklist proposed by PRISMA-ScR. SOURCES: Searches were conducted in PubMed/MEDLINE, Web of Science, Scopus, and grey literature up to August 2023. RESULTS: A total of 455 studies were identified. After screening, 16 studies were deemed suitable for scoping review. Of these, 13 were in vitro studies, two were case reports, and one was a clinical study. Different IOS systems for scanning post spaces were evaluated, with Trios being most prevalent, followed by Prismescan. While most studies did not use any intraoral scanning devices, five studies reported the use of scan posts. Results regarding retention favored fully digital workflows. However, results about the adaptation and accuracy varied between included studies, highlighting the importance of standardized approaches. Future clinical studies should encompass variations in IOS systems, post space depths, scanner depth of field, light conditions, scan post utilization, operator experience, scanning time and strategy, and direct comparison with conventional techniques. CONCLUSION: IOS is increasingly important in capturing digital impressions for post spaces and provides valuable insights for clinicians and researchers. Although included studies, primarily in vitro, demonstrated promising results for the utilization of IOS systems in fully digital workflows for post and core restorations, further well-conducted studies, particularly clinical trials, are recommended due to data heterogeneity and limitations. CLINICAL SIGNIFICANCE: This mapping highlights the potential of modern IOS in fully digital workflows for post and core restorations. Despite promising results, challenges related to different variables associated with IOS require careful consideration. Standardization and additional clinical validation are essential for optimize IOS benefits in post and core restorations.


Assuntos
Desenho Assistido por Computador , Restauração Dentária Permanente , Fluxo de Trabalho , Humanos , Restauração Dentária Permanente/métodos , Planejamento de Prótese Dentária/métodos
19.
Molecules ; 29(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38675620

RESUMO

Breast cancer is a major global health issue, causing high incidence and mortality rates as well as psychological stress for patients. Chemotherapy resistance is a common challenge, and the Aldo-keto reductase family one-member C3 enzyme is associated with resistance to anthracyclines like doxorubicin. Recent studies have identified celecoxib as a potential treatment for breast cancer. Virtual screening was conducted using a quantitative structure-activity relationship model to develop similar drugs; this involved backpropagation of artificial neural networks and structure-based virtual screening. The screening revealed that the C-6 molecule had a higher affinity for the enzyme (-11.4 kcal/mol), a lower half-maximal inhibitory concentration value (1.7 µM), and a safer toxicological profile than celecoxib. The compound C-6 was synthesized with an 82% yield, and its biological activity was evaluated. The results showed that C-6 had a more substantial cytotoxic effect on MCF-7 cells (62%) compared to DOX (63%) and celecoxib (79.5%). Additionally, C-6 had a less harmful impact on healthy L929 cells than DOX and celecoxib. These findings suggest that C-6 has promising potential as a breast cancer treatment.


Assuntos
Membro C3 da Família 1 de alfa-Ceto Redutase , Anti-Inflamatórios não Esteroides , Neoplasias da Mama , Desenho de Fármacos , Humanos , Neoplasias da Mama/tratamento farmacológico , Feminino , Membro C3 da Família 1 de alfa-Ceto Redutase/antagonistas & inibidores , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/química , Células MCF-7 , Desenho Assistido por Computador , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Quantitativa Estrutura-Atividade , Simulação de Acoplamento Molecular , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Celecoxib/farmacologia , Celecoxib/química , Proliferação de Células/efeitos dos fármacos
20.
Eur J Prosthodont Restor Dent ; 32(3): 244-253, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38591546

RESUMO

PURPOSE: The composition and properties of resin-based composite materials could affect tooth wear and lead to clinical problems. Therefore, the study objective was to characterize human tooth wear behavior against a bulk-fill restorative (BF) compared to a conventional resin composite (RC) and a CAD/CAM resin nano ceramic (RN). METHODS: Square-shaped specimens of each material were prepared and sub-divided according to the number of testing cycles (n=8): 100,000, 250,000, and 500,000 cycles. An occlusal wear test was performed using a chewing machine with 49 N, 2 Hz, in 37°C distilled water. Human premolar cusps were used as antagonists. Micro-CT and laser scanner were used to scan antagonists and specimens, respectively. Wear volume was assessed using a software and the wear pattern was examined with SEM. Softening in solvent analysis was performed by measuring the materials' Knoop microhardness (KHN) before and after immersion in ethanol. Wear volume data were analyzed with two-way ANOVA and Student-Neuman-Keuls test (α=0.05). RESULTS: For tooth and specimen wear volume, there was statistical significance for material and number of cycles, but not for the interaction between factors. BF resulted in less tooth (p=0.008) and specimen (p=0.030) wear than RN and RC, which were similar (p⟩0.05). Volume loss increased from 100,000 to 500,000 cycles. BF showed the lowest microhardness (KHN1); and %ΔKHN similar to RC, but greater than RN. CONCLUSION: BF induced less volume loss to the tooth than RC and RN, while presenting greater wear resistance. The tooth wear pattern and damage progression were mild for all materials. CLINICAL SIGNIFICANCE: Resin composites show favorable wear behavior, leading to low volume loss and mild structural damage of the tooth. Regular bulk-fill resin composite stands out for its efficient restorative technique, low wear susceptibility and reduced capacity to wear down the tooth.


Assuntos
Resinas Compostas , Teste de Materiais , Desgaste dos Dentes , Resinas Compostas/química , Humanos , Restauração Dentária Permanente/métodos , Propriedades de Superfície , Desenho Assistido por Computador , Técnicas In Vitro , Desgaste de Restauração Dentária , Dureza , Materiais Dentários/química
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