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1.
Int J Esthet Dent ; 19(3): 212-225, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092817

RESUMO

Digital technologies are gradually gaining ground in dentistry. In particular, taking impressions with intraoral scanners is becoming routine; however, even this must often be preceded by the use of retraction cords. This article presents an innovative technique to record digital impressions of natural tooth abutments using interim restorations relined with impression material instead of retraction cords. In the laboratory, using computer-aided design, the technician can segment the internal surface of the interim restoration and use it to replace the abutment of the intraoral scan, thus obtaining an accurate coping that yields more detailed information about the supragingival and intrasulcular surface of the preparation.


Assuntos
Desenho Assistido por Computador , Dente Suporte , Técnica de Moldagem Odontológica , Humanos , Materiais para Moldagem Odontológica/química
2.
Br Dent J ; 237(1): 28-32, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38997367

RESUMO

Introduction A little over ten years ago, zirconia crowns made their debut in the field of dentistry. Despite early problems with the chipping of veneering porcelain, clinical studies have demonstrated excellent performance. It is essential for a ceramic crown to have good aesthetic qualities, in addition to having good mechanical characteristics. The exceptional mechanical qualities of zirconia crowns and the simplicity with which they may be machined, employing computer-aided design and computer-aided manufacturing schemes, are primarily responsible for the widespread use of these materials in clinical settings. New ceramic-based materials, including monolithic zirconia, zirconia-containing lithium disilicate ceramics, and graded glass/zirconia/glass, have recently been launched in the field of dentistry. These newly discovered zirconia crown materials stem from varied technological approaches, each likely to lead to additional clinical advancements. At this point, it seems imperative to offer a concentrated report on the newer developments, along with essential clinical recommendations for best clinical outcomes with zirconia crowns.Types of studies This review article is a consolidation of several case studies, cohort studies and systematic reviews, as well as experimental and observational randomised control trials and other peer-reviewed articles.Results On reviewing, a concise list of clinical recommendations is generated, demonstrating that monolithic zirconia offers some clinical advantages over veneered zirconia crowns.Conclusion This review article discloses various clinical revelations and in-office recommendations for favourable usage of zirconia ceramic crowns that can lead to better patient outcomes and long-term clinical success rates.


Assuntos
Cerâmica , Coroas , Zircônio , Humanos , Desenho Assistido por Computador , Planejamento de Prótese Dentária/métodos , Materiais Dentários , Estética Dentária , Porcelana Dentária
3.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(4): 481-485, 2024 Aug 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39049636

RESUMO

OBJECTIVES: This study aimed to evaluate the application of digital impression and resin model technology in removable partial dentures (RPD) for Kennedy classⅠandⅡdentition defects. METHODS: Patients with Kennedy classⅠorⅡdental defect were selected and grouped in accordance with the following denture production processes: digital impression/resin model/cast cobalt-chromium alloy framework group (group A), digital impression/resin model/laser printed titanium framework group (group B), alginate impression/plaster model/cast cobalt-chromium alloy framework group (group C), and alginate impression/plaster model/laser printed titanium framework group (group D), with 40 cases in each group. The final RPD was examined in place in the mouth, and the evaluation indicators included the retention force of clamp ring, the tightness of connector and base, and the accuracy of occlusion. The evaluation scores of each index were used for analysis on the Kruskal-Wallis rank-sum test. RESULTS: No statistically significant difference in the score of each index was found among the four groups in RPD. CONCLUSIONS: The cast cobalt-chromium alloy and laser-printed titanium framework RPD using digital impression and resin model can meet the clinical restoration requirements of patients with Kennedy classⅠandⅡdentition defects.


Assuntos
Técnica de Moldagem Odontológica , Planejamento de Dentadura , Prótese Parcial Removível , Humanos , Ligas de Cromo , Titânio , Lasers , Desenho Assistido por Computador
4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(4): 538-542, 2024 Aug 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39049643

RESUMO

This study explores the potential application of computer aided design (CAD)/computer aided manufac-turing (CAM) for one-piece glass fiber posts and cores in restoring tooth defects post-removal of a broken fiber post using a digital guide plate. This paper reports a fractured left upper incisor fiber post removed using a customized needle and digital guide plate. Following root canal retreatment, CAD/CAM integrated fiber post-core and zirconia full crown restoration were completed. The occlusion testing was conducted using the T-Scan Ⅲ system. This study offers insights for managing secondary repair after fiber post fractures.


Assuntos
Vidro , Técnica para Retentor Intrarradicular , Humanos , Desenho Assistido por Computador , Incisivo/cirurgia , Zircônio , Coroas , Tratamento do Canal Radicular
5.
PeerJ ; 12: e17793, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39040936

RESUMO

Artificial intelligence (AI) is increasingly prevalent in biomedical and industrial development, capturing the interest of dental professionals and patients. Its potential to improve the accuracy and speed of dental procedures is set to revolutionize dental care. The use of AI in computer-aided design/computer-aided manufacturing (CAD/CAM) within the restorative dental and material science fields offers numerous benefits, providing a new dimension to these practices. This study aims to provide a concise overview of the implementation of AI-powered technologies in CAD/CAM restorative dental procedures and materials. A comprehensive literature search was conducted using keywords from 2000 to 2023 to obtain pertinent information. This method was implemented to guarantee a thorough investigation of the subject matter. Keywords included; "Artificial Intelligence", "Machine Learning", "Neural Networks", "Virtual Reality", "Digital Dentistry", "CAD/CAM", and "Restorative Dentistry". Artificial intelligence in digital restorative dentistry has proven to be highly beneficial in various dental CAD/CAM applications. It helps in automating and incorporating esthetic factors, occlusal schemes, and previous practitioners' CAD choices in fabricating dental restorations. AI can also predict the debonding risk of CAD/CAM restorations and the compositional effects on the mechanical properties of its materials. Continuous enhancements are being made to overcome its limitations and open new possibilities for future developments in this field.


Assuntos
Inteligência Artificial , Desenho Assistido por Computador , Materiais Dentários , Humanos , Restauração Dentária Permanente/métodos , Planejamento de Prótese Dentária/métodos
6.
Shanghai Kou Qiang Yi Xue ; 33(2): 200-204, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-39005100

RESUMO

PURPOSE: To analyse the types of chairside CAD/CAM all-ceramic restorations and the color range of all-ceramic materials used so as to provide reference for the application of clinical chairside all-ceramic restoration and the color selection of all-ceramic materials. METHODS: IPS e.max CAD prostheses and related data were collected from January 2021 to December 2021 from the Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine. The number and type of restorations and the color of materials were investigated and analyzed by descriptive statistics. RESULTS: A total of 1 374 restorations were included, of which 624 were crown restorations, accounting for 45.41% of the total restorations. 516 cases were veneer, accounting for 37.55%; 219 were inlays, accounting for 15.94%; fixed bridges were all adhesive bridges, with the least number with only 15 cases, accounting for 1.09%. In terms of the selection of restoration materials, the use rate of low-transparent(LT) ceramic blocks was significantly higher than that of other transparent ceramic blocks. A was the most frequently used ceramic color. The most frequently used porcelain blocks for veneers were LTA2 and LTA1; for inlay were LTA3; for crowns were LTA2 and LTA3. The blocks used in the fixed bridges were all LT, and A3 color was the majority. CONCLUSIONS: Chairside CAD/CAM all-ceramic prostheses made of IPS e.max CAD materials have been widely used in clinical practice. The types of prostheses include veneer, inset, crown and fixed bridge. The most commonly used IPS e.max CAD blocks are LTA2, LTA3 and LTA1. These findings have certain guiding significance for the clinical restoration decision and the reserve of porcelain blocks in primary hospitals.


Assuntos
Cerâmica , Desenho Assistido por Computador , Coroas , Cerâmica/química , Planejamento de Prótese Dentária/métodos , Porcelana Dentária/química , Cor , Humanos , Facetas Dentárias , Restaurações Intracoronárias/métodos , Restauração Dentária Permanente/métodos
7.
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.
Bioinspir Biomim ; 19(5)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38991522

RESUMO

This work examines the acoustically actuated motions of artificial flagellated micro-swimmers (AFMSs) and compares the motility of these micro-swimmers with the predictions based on the corrected resistive force theory (RFT) and the bar-joint model proposed in our previous work. The key ingredient in the theory is the introduction of a correction factorKin drag coefficients to correct the conventional RFT so that the dynamics of an acoustically actuated AFMS with rectangular cross-sections can be accurately modeled. Experimentally, such AFMSs can be easily manufactured based on digital light processing of ultra-violet (UV)-curable resins. We first determined the viscoelastic properties of a UV-cured resin through dynamic mechanical analysis. In particular, the high-frequency storage moduli and loss factors were obtained based on the assumption of time-temperature superposition (TTS), which were then applied in theoretical calculations. Though the extrapolation based on the TTS implied the uncertainty of high-frequency material response and there is limited accuracy in determining head oscillation amplitude, the differences between the measured terminal velocities of the AFMSs and the predicted ones are less than 50%, which, to us, is well acceptable. These results indicate that the motions of acoustic AFMS can be predicted, and thus, designed, which pave the way for their long-awaited applications in targeted therapy.


Assuntos
Simulação por Computador , Desenho de Equipamento , Modelos Biológicos , Natação , Natação/fisiologia , Análise de Falha de Equipamento , Materiais Biomiméticos/química , Biomimética/métodos , Robótica/métodos , Robótica/instrumentação , Som , Acústica , Desenho Assistido por Computador , Animais
10.
Clin Oral Investig ; 28(8): 417, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38972945

RESUMO

OBJECTIVES: The treatment of fractures prioritizes the restoration of functionality through the realignment of fractured segments. Conventional methods, such as titanium plates, have been employed for this purpose; however, certain limitations have been observed, leading to the development of patient-specific plates. Furthermore, recent advancements in digital technology in dentistry enable the creation of virtual models and simulations of surgical procedures. The aim was to assess the clinical effectiveness of patient-specific plates utilizing digital technology in treating mandibular fractures compared to conventional titanium plates. MATERIALS AND METHODS: Twenty patients diagnosed with mandibular fractures were included and randomly assigned to either the study or control groups. The surgical procedure comprised reduction and internal fixation utilizing patient-specific plates generated through virtual surgery planning with digital models for the study group, while the control group underwent the same procedure with conventional titanium plates. Assessment criteria included the presence of malunion, infection, sensory disturbance, subjective occlusal disturbance and occlusal force in functional maximum intercuspation (MICP). Statistical analysis involved using the Chi-square test and one-way repeated measures analysis of variance. RESULTS: All parameters showed no statistically significant differences between the study and control groups, except for the enhancement in occlusal force in functional MICP, where a statistically significant difference was observed (p = 0.000). CONCLUSION: Using patient-specific plates using digital technology has demonstrated clinical effectiveness in treating mandibular fractures, offering advantages of time efficiency and benefits for less experienced surgeons. CLINICAL RELEVANCE: Patient-specific plates combined with digital technology can be clinically effective in mandibular fracture treatment.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas , Fraturas Mandibulares , Titânio , Humanos , Fraturas Mandibulares/cirurgia , Titânio/química , Masculino , Feminino , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Adulto , Resultado do Tratamento , Pessoa de Meia-Idade , Desenho Assistido por Computador , Cirurgia Assistida por Computador/métodos
11.
BMC Oral Health ; 24(1): 770, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38982396

RESUMO

BACKGROUND: High precision intra-oral scans, coupled with advanced software, enable virtual bracket removal (VBR) from digital models. VBR allows the delivery of retainers and clear aligners promptly following debonding, thus reducing the patients' appointments and minimizing the likelihood of tooth movement. The objective of this study was to compare the enamel surface before bonding and after VBR using three different Computer-aided design (CAD) software and to compare their accuracy. METHODS: Maxillary scans of 20 participants starting orthodontic treatment were selected for inclusion in the study, who exhibited mild to moderate crowding and required bonding of brackets on the labial surface of permanent maxillary teeth (from the maxillary left first molar to the maxillary right first molar). Two intra-oral scans were conducted on the same day, before bonding and immediately after bonding using CEREC Omnicam (Sirona Dental Systems, Bensheim, Germany). The virtual removal of the brackets from the post-bonding models was performed using OrthoAnalyzer (3Shape, Copenhagen, Denmark), Meshmixer (Autodesk, San Rafael, Calif, USA), and EasyRx (LLC, Atlanta, GA, USA) software. The models that underwent VBR were superimposed on the pre-bonding models by Medit Link App (Medit, Seoul, South Korea) using surface-based registration. The changes in the enamel surface following VBR using the three software packages were quantified using the Medit Link App. RESULTS: There was a significant difference among the 3Shape, Meshmixer, and EasyRx software in tooth surface change following VBR. Specifically, EasyRx exhibited lower levels of accuracy compared to the other two VBR software programs (p<.001, p<.001). A significant difference in enamel surface change was observed between tooth segments across all software groups, in both incisors and molars, with VBR of the molars exhibiting the lowest level of accuracy (3Shape p=.002, Meshmixer p<.001, EasyRx p<.001). Regarding the direction of tooth surface changes following VBR, it was observed that all three groups exhibited a significant increase in the percentage of inadequate bracket removal across all teeth segments. CONCLUSIONS: 3Shape and Meshmixer manual VBR software were found to be more accurate than EasyRx automated software, however, the differences were minimal and clinically insignificant.


Assuntos
Braquetes Ortodônticos , Software , Humanos , Desenho Assistido por Computador , Descolagem Dentária/métodos , Feminino , Adolescente , Masculino , Modelos Dentários , Esmalte Dentário , Má Oclusão/terapia , Colagem Dentária/métodos
13.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 59(7): 690-695, 2024 Jul 09.
Artigo em Chinês | MEDLINE | ID: mdl-38949137

RESUMO

Objective: To investigate the effect of zirconia personalized gingival structure on peri-implant soft and hard tissue stability after single-tooth implant restorations in patients with thin gingival biotypes in the anterior region, with a view to provide a clinical guideline. Methods: This retrospective study included 20 patients with thin gingival biotype and implant restorations in the anterior region. These patients included 9 males and 11 females, and the age was (35.2± 10.3) years. The patients were from the Department of Periodontal Implantology, Stomatology Hospital, Southern Medical University from January 2018 to December 2022. Computer-aided design/computer-aided manufacturing (CAD/CAM) techniques were used to fabricate a titanium base zirconia personalized gingival structure to maintain the soft-tissue perforated gingival contour of the anterior esthetic zone. This structure consists of two modalities: titanium base + zirconia outer crown or titanium base personalized zirconia abutment + zirconia outer crown. Clinical outcomes were recorded immediately and after delivery of the final restorations. Implant retention was recorded, esthetic scoring was performed using the pink esthetic index, the amount of bone resorption at the implant margins was measured based on digitized apical radiographs, and periodontal health was evaluated using the modified plaque index and the modified bleeding index. Results: The survival rate of the 20 implants was 100% after 3 years of wearing the final restorations, with a pink aesthetic score of 9.3±0.9. Bone resorption at the proximal and distal mesial margins of the implants was 0.09 (-0.21, 0.20) mm, 0.17 (-0.12, 0.27) mm after 3 years, respectively, and the difference was not statistically significant when compared to bone resorption immediately after placement of the final restoration [0(0, 0) mm] (Z=-1.03, P=0.394; Z=-2.05, P=0.065). Conclusions: Zirconia personalized gingival structure maintains the stability of peri-implant hard and soft tissues of thin gingival biotypes in the anterior region.


Assuntos
Estética Dentária , Gengiva , Zircônio , Humanos , Masculino , Feminino , Estudos Retrospectivos , Adulto , Desenho Assistido por Computador , Implantes Dentários para Um Único Dente , Titânio , Coroas
14.
BMC Oral Health ; 24(1): 760, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965507

RESUMO

BACKGROUND: Preservation of the remaining structures while maintaining an esthetic appearance is a major objective in removable partial prosthodontics. So, the aim of the current study was to compare the stresses induced on the supporting structures by two digitally produced esthetic core materials; Zirconia and Polyetheretherketone when used as an extracoronal attachment in distal extension removable partial dentures using strain gauge analysis. METHODS: A mandibular Kennedy class II stone cast with the necessary abutments' preparations was scanned. The mandibular left canine and first premolar teeth were virtually removed. An acrylic mandibular left canine and first premolar teeth were prepared with heavy chamfer finish line and scanned. Virtual superimposition of the acrylic teeth in their corresponding positions was done. Two strain gauge slots were designed: distal to the terminal abutment and in the residual ridge. Two models and two sets of scanned teeth were digitally printed. The printed teeth were then placed in their corresponding sockets in each model and scanned. The attachment design was selected from the software library and milled out of Zirconia in the model ZR and Polyetheretherketone in the model PE. Five removable partial dentures were constructed for each model. The strain gauges were installed in their grooves. A Universal testing machine was used for unilateral load application of 100 N (N). For each removable partial denture, five measurements were made. The data followed normal distribution and were statistically analyzed by using unpaired t test. P value < 0.05 was considered to be statistically significant. RESULTS: During unilateral loading unpaired t test showed statistically significant difference (p = 0.0001) in the microstrain values recorded distal to the abutment between the models ZR (-1001.6 µÎµ ± 24.56) and PE (-682.6 µÎµ ± 22.18). However, non statistically significant difference (p = 0.3122) was observed in the residual ridge between them; ZR (16.2 µÎµ ± 4.53) and PE (15 µÎµ ± 3.74). CONCLUSIONS: In removable partial dentures, Polyetheretherketone extracoronal attachment induces less stress on the supporting abutments compared to the zirconia one with no difference in the stresses induced by them on the residual ridge.


Assuntos
Benzofenonas , Planejamento de Dentadura , Prótese Parcial Removível , Cetonas , Polímeros , Zircônio , Cetonas/química , Humanos , Zircônio/química , Polietilenoglicóis , Análise do Estresse Dentário , Materiais Dentários/química , Desenho Assistido por Computador , Dente Suporte , Estresse Mecânico , Estética Dentária , Teste de Materiais
15.
Compend Contin Educ Dent ; 45(7): 372-374, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39029965

RESUMO

In the past decade, the shifting of dentistry into the digital world has become obvious to any dentist or dental specialist. Many restorative dentists now consider themselves "digital dentists," performing all their crown and bridge restorative planning and fabrication in a digital environment. In preparation for this article, the author asked both a prosthodontist and the owner of a large state-of-the-art dental laboratory with whom he has worked closely the following questions: "These days, what percentage of your crown and bridge cases are being done fully digital?" Then, "What is the answer to the same question 5 years ago?" The prosthodontist answered that for crowns and bridges (with some exceptions for bridges), including implants (but not full arches), "close to 100 percent" of cases are now fully digital, while "maybe 25 percent" were 5 years ago (personal communication with Jason Sauer, DDS, of Westchester Prosthodontics, White Plains, New York, March 29, 2024). The dental laboratory owner answered, "My lab is different than others. We're about 60 percent digital, but digital is rapidly increasing. I'd say the majority of labs are 80 to 90 percent digital. Five years ago, we were 70 to 80 percent hand (analog.) We went from three mills pre-Covid to 30 different machines post-Covid (printers, mills, and scanners)" (personal communication with Steven Pigliacelli, MDT, of Marotta Dental Studio, Farmingdale, New York, March 29, 2024). It's fair to say that these comments show that the implementation of digital technologies in dentistry has been dramatic and will continue to expand.


Assuntos
Tecnologia Digital , Humanos , Desenho Assistido por Computador , Planejamento de Prótese Dentária/métodos , Implantação Dentária/métodos , Implantes Dentários
16.
BMC Oral Health ; 24(1): 845, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060942

RESUMO

BACKGROUND: The fit of a metal-ceramic restoration is essential to its long-term durability. Regarding marginal and internal fit, there is not enough information about the technologies used in the production of metal-ceramic restorations. The aim of this in vitro study is to compare, both before and after porcelain firing, the marginal, axial, axio-occlusal, and occlusal fit of metal-ceramic restorations manufactured using casting, additive or subtractive computer-aided design, and computer-aided manufacturing techniques (CAD/CAM). METHODS: CAD/CAM were used to create 50 prepared maxillary first molar-shaped Co-Cr die models, which were randomly divided into 5 groups (n = 10). Cobalt-chrome copings were produced by casting (C), hard metal milling (HM), soft metal milling (SM), selective laser melting (SLM), and selective laser sintering (SLS) techniques. Before and after porcelain firing, discrepancies of the copings were measured using the silicone replica technique. The data obtained by measurements with a stereomicroscope at x80 magnification were analyzed statistically in the SPSS program. The ROBUST three-way analysis of variance (ANOVA) method was used to compare the discrepancy values. RESULTS: There were statistically significant differences among fabrication methods (P < .001). The HM method showed the highest discrepancy (90.1 µm), and the C (63 µm) method showed the lowest discrepancy in terms of the die model- crown fit. The C, SLS, and SM methods (63 µm; 61.6 µm; 67.7 µm) were statistically similar (P > .001). The highest discrepancy was observed on the occlusal area (87.1 µm), and the lowest discrepancy was observed on the axial area (47.7 µm) of the coping. Porcelain firing had a decrease in the discrepancy values (P = .001). CONCLUSION: All CAD/CAM techniques are appropriate for clinical use; selective laser sintering and soft milling can be the more recommended methods for the compatibility of metal-porcelain restorations, as they have lower discrepancy values than the SLM and HM methods.


Assuntos
Desenho Assistido por Computador , Coroas , Porcelana Dentária , Planejamento de Prótese Dentária , Ligas Metalo-Cerâmicas , Ligas Metalo-Cerâmicas/química , Porcelana Dentária/química , Humanos , Técnica de Fundição Odontológica , Adaptação Marginal Dentária , Técnicas In Vitro , Ligas de Cromo/química
17.
Comput Methods Programs Biomed ; 254: 108318, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38991374

RESUMO

BACKGROUND AND OBJECTIVE: While numerous in silico tools exist for target-based drug discovery, the inconsistent integration of in vitro data with predictive models hinders research and development productivity. This is particularly apparent during the Hit-to-Lead stage, where unreliable in-silico tools often lead to suboptimal lead selection. Herein, we address this challenge by presenting a CADD-guided pipeline that successfully integrates rational drug design with in-silico hits to identify a promising DDR1 lead. METHODS: 2 × 1000 ns MD simulations along with their respective FEL and MMPBSA analyses were employed to guide the rational design and synthesis of 12 novel compounds which were evaluated for their DDR inhibition. RESULTS: The molecular dynamics investigation of the initial hit led to the identification of key structural features within the DDR1 binding pocket. The identified key features were used to guide the rational design and synthesis of twelve novel derivatives. SAR analysis, biological evaluation, molecular dynamics, and free energy calculations were carried out for the synthesized derivatives to understand their mechanism of action. Compound 4c exhibited the strongest inhibition and selectivity for DDR1, with an IC50 of 0.11 µM. CONCLUSIONS: The MD simulations led to the identification of a key hydrophobic groove in the DDR1 binding pocket. The integrated approach of SAR analysis with molecular dynamics led to the identification of compound 4c as a promising lead for further development of potent and selective DDR1 inhibitors. Moreover, this work establishes a protocol for translating in silico hits to real world bioactive druggable leads.


Assuntos
Receptor com Domínio Discoidina 1 , Desenho de Fármacos , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases , Receptor com Domínio Discoidina 1/antagonistas & inibidores , Humanos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Desenho Assistido por Computador , Sítios de Ligação , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular
18.
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
19.
BMC Oral Health ; 24(1): 764, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970004

RESUMO

BACKGROUND: This clinical study aims to evaluate the accuracy of the conventional implant impression techniques compared to the digital impression ones in bilateral distal extension cases. METHODS: A total of 32 implants were placed in eight patients missing all mandibular posterior teeth except the first premolars. Each patient received a total of four implants, with two implants placed on each side, in order to provide support for three units of screw-retained zirconia restorations. Following osteointegration, the same patient underwent two implant-level impression techniques: Conventional open-tray impressions CII (splinted pick-up) and digital implant impressions DII with TRIOS 3 Shape intraoral scanner. The accuracy of impressions was evaluated utilizing a three-dimensional superimposition analysis of standard tessellation language (STL) files. Subsequently, the scan bodies were segmented using Gom inspect software to measure three-dimensional deviations in a color-coding map. Data were statistically analyzed using the Kruskal Wallis test and then a post-hoc test to determine the significance level (P < 0.05). RESULTS: The study revealed that higher angular and positional deviations were shown toward distal scan bodies compared to mesial ones for both impression techniques. However, this difference was not statistically significant (P > 0.05). CONCLUSION: Splinted open-tray conventional impression and intraoral scanning implant impression techniques have demonstrated comparable accuracy. TRIAL REGISTRATION: Clinical Trials.gov Registration ID NCT05912725. Registered 22/06/ 2023- Retrospectively registered, https://register. CLINICALTRIALS: gov .


Assuntos
Técnica de Moldagem Odontológica , Humanos , Feminino , Masculino , Implantes Dentários , Desenho Assistido por Computador , Adulto , Pessoa de Meia-Idade , Imageamento Tridimensional/métodos
20.
BMC Oral Health ; 24(1): 765, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970080

RESUMO

OBJECTIVE: To determine the effects of conventional cigarette smoking (CS) and recent heated tobacco products (HTPs) on the surface roughness and color stability of different indirect restorative materials. MATERIALS AND METHODS: One hundred disc-shaped samples were constructed of three different restorative CAD/CAM materials: lithium disilicate glass-ceramic (IPS e.max CAD; Ivoclar Vivadent, Liechtenstein), zirconia (BruxZir® Zirconia, Glidewell, USA) and polyetheretherketone (BioHPP® bredent GmbH, Germany). Of the IPS e.max CAD and the Bruxzir samples, 20 samples were glazed, and 20 samples were polished, while the BioHPP samples were all polished according to the manufacturer's instructions. Fifty samples were subjected to conventional cigarette smoking (LM, Philip Morris International Inc., Egypt) (Groups: IPS e.max CAD_Glazed exposed to CS (LD_G_Cig), IPS e.max CAD_Polished exposed to CS (LD_P_Cig), Bruxzir_Glazed exposed to CS (Zr_G_Cig), Bruxzir _Polished exposed to CS (Zr_P_Cig) and BioHPP exposed to CS (PEEK_Cig) and fifty samples were exposed to heated tobacco product smoking (Heets, Russet selection, Philip Morris International Inc., Italy) (Groups: IPS e.max CAD_Glazed exposed to HTP (LD_G_HTP), IPS e.max CAD_Polished exposed to HTP (LD_P_HTP), Bruxzir_Glazed exposed to HTP (Zr_G_HTP), Bruxzir CAD_Polished exposed to HTP (Zr_P_HTP) and BioHPP exposed to HTP (PEEK_HTP).. Six hundred cigarettes/heets representing 30 days of medium smoking behavior (20 cigarettes/day) were used. Before and after exposure to smoke, the surface roughness of all the samples was measured using JITAI8101 surface roughness tester (Beijing Jitai Tech Detection Device Co., Ltd, China, and the color parameters were assessed using VITA Easyshade Advance 4.01 (VITA shade, VITA made, VITA). The data were analyzed using One-way ANOVA, paired sample t-test and independent sample t-test. The significance level was set at α < 0.05. The surface topography was evaluated by scanning electron microscopy (SEM) and analyzed using energy-dispersive X-ray (EDX) spectroscopy to determine changes in the surface chemical composition. RESULTS: Both types of smoking caused significant increases in the surface roughness of all the samples. There was a significant difference in color change between CS and HTP for all materials with different surface finish (P < 0.01) and zirconia had the greatest effect on color change (P < 0.001). In contrast, polyetheretherketone (PEEK) "BioHPP" had the least effect (P < 0.001). CONCLUSION: Exposure to different types of smoking induce changes in the surface topography and color of different esthetic restorative materials. Compared with HTP, conventional cigarette smoke has a greater effect on the surface roughness and color stability of esthetic restorative materials. The glazed surfaces showed less change in surface topography than did the polished surfaces. Zirconia showed better color stability when compared to polyetheretherketone (PEEK).


Assuntos
Cerâmica , Fumar Cigarros , Desenho Assistido por Computador , Materiais Dentários , Porcelana Dentária , Cetonas , Polietilenoglicóis , Polímeros , Propriedades de Superfície , Produtos do Tabaco , Zircônio , Polietilenoglicóis/química , Zircônio/química , Produtos do Tabaco/efeitos adversos , Cerâmica/química , Cetonas/química , Porcelana Dentária/química , Fumar Cigarros/efeitos adversos , Materiais Dentários/química , Benzofenonas , Teste de Materiais , Temperatura Alta , Humanos , Cor , Restauração Dentária Permanente
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