Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.006
Filtrar
1.
Niger J Clin Pract ; 23(8): 1178-1181, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32788499

RESUMEN

Restoration of the malaligned dental implants in the esthetic zone is a challenge for dental practitioner because of the difficulty in obtaining balance and harmony between position and color of the final prosthesis and the adjacent teeth. Mesostructure is a part of the prosthesis that located ontop of the dental implant and bearing the final prosthesis. It has a form of milled bar to bear an overdenture or as abutment used for the correction of malaligned dental implants. Such approach maintains screw-retained prosthesis option while allowing complete retrievability, improved accessibility, usage of thicker abutment screws, and acceptable esthetic outcomes. In this case report, a two-piece mesostructure was designed to correct the malposition of dental implants in the esthetic zone with 1-year follow-up system.


Asunto(s)
Tornillos Óseos , Implantes Dentales , Diseño de Prótesis Dental , Estética Dental , Maxilar/cirugía , Anciano , Diseño de Prótesis Dental/métodos , Prótesis Dental de Soporte Implantado , Odontólogos , Prótesis de Recubrimiento , Femenino , Humanos , Rol Profesional , Resultado del Tratamiento
2.
BMC Oral Health ; 20(1): 201, 2020 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-32650758

RESUMEN

BACKGROUND: The premature loss of primary teeth is a common problem in pediatric dentistry, resulting in disruption of the arch integrity. Hence, space maintainers (SM) used for maintaining spaces are necessary. However, current methods of making removable space maintainers (RSM) have some limitations. METHODS: Digital models of dentition defects were obtained by using a scanning technique coupled with laser medical image reconstruction. The digital RSMs were designed using the 3Shape software. They were manufactured using two methods: polyetheretherketone (PEEK), and conventional methods (20 RSMs per group). For qualitative evaluation, the Likert five-point scale was used by 10 experts to obtain a score for 40 RSMs. The spaces between the tissue surfaces of the RSMs and the models were replaced using silicone, and the maximum and mean distances, as well as the standard deviation, were measured. A three-dimensional variation analysis was used to measure these spaces. The student's t-test and Satterthwaite t-test were used to compare the differences in the spaces for the various materials. RESULTS: The PEEK RSMs were found to fit the models well. In the qualitative assessment, the mean experts' scores for the PEEK and conventional groups were 1.80 ± 0.40 and 1.82 ± 0.40, and there was no significant difference between the two groups (p = 0.875). In the quantitative assessment, the mean spaces for the PEEK digital RSMs and the conventional RSMs were 44.32 ± 1.75 µm, and 137.36 ± 18.63 µm, respectively, and the differences were statistically significant (p < 0.001). In addition, there were significant differences in the maximum space and the standard deviation between the two groups. CONCLUSION: Digitally designed and integrated RSMs were found to be superior to those produced using the conventional method. 3D variation analysis results showed that the mean distances and standard deviations of the PEEK groups were significantly smaller than those of conventional group (p < 0.01). A PEEK-manufactured RSM produced using CAD/CAM would be extremely suitable for clinical applications.


Asunto(s)
Diseño Asistido por Computadora , Diseño de Prótesis Dental/métodos , Dentadura Parcial Removible , Cetonas , Polietilenglicoles , Niño , Humanos
3.
BMC Oral Health ; 20(1): 20, 2020 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-31973720

RESUMEN

BACKGROUND: Advanced digital workflows in orthodontics and dentistry often require a combination of different software solutions to create patient appliances, which may be a complex and time-consuming process. The main objective of this technical note is to discuss treatment of craniofacial anomalies using digital technologies. We present a fully digital, linear workflow for manufacturing palatal plates for infants with craniofacial anomalies based on intraoral scanning. Switching to intraoral scanning in infant care is advantageous as taking conventional impressions carries the risk of impression material aspiration and/or infections caused by material remaining in the oronasal cavity. MATERIAL AND METHODS: The fully digital linear workflow presented in this technical note can be used to design and manufacture palatal plates for cleft palate patients as well as infants with functional disorders. We describe the workflow implemented in an infant with trisomy 21. The maxilla was registered using a digital scanner and a stimulation plate was created using dental CAD software and an individual impression tray module on a virtual model. Plates were manufactured using both additive and subtractive methods. Methacrylate based light curing resin and Poly-Ether-Ether-Ketone were the materials used. RESULTS: The palatal area was successfully scanned to create a virtual model. The plates fitted well onto the palatal area. Manual post-processing was necessary to optimize a functional ridge along the vestibular fold and remove support structures from the additively manufactured plate as well as the milled plate produced from a blank. The additively manufactured plate fitted better than the milled one. CONCLUSION: Implementing a fully digital linear workflow into clinical routine for treatment of neonates and infants with craniofacial disorders is feasible. The software solution presented here is suitable for this purpose and does not require additional software for the design. This is the key advantage of this workflow, which makes digital treatment accessible to all clinicians who want to deal with digital technology. Whether additive or subtractive manufacturing is preferred depends on the appliance material of choice and influences the fit of the appliance.


Asunto(s)
Anomalías Craneofaciales/diagnóstico por imagen , Diseño de Prótesis Dental/métodos , Síndrome de Down , Impresión Tridimensional , Flujo de Trabajo , Diseño Asistido por Computadora , Técnica de Impresión Dental/instrumentación , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Lactante , Recién Nacido , Tecnología Odontológica/métodos
4.
PLoS One ; 15(1): e0227050, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31945072

RESUMEN

OBJECTIVES: To better guide clinicians to choose the appropriate chairside system, we compared and evaluated the morphology of crowns generated by three different biogeneric design modes (biogeneric copy (BC), biogeneric individual (BI), and biogeneric reference (BR)) of the CEREC software. METHODS: Maxillary and mandibular casts were obtained from twelve volunteers and digital impressions were acquired. All ceramic crown preparations of all right maxillary central incisors were prepared and digital impressions were taken. Then, crowns were automatically designed under BC, BI and BR modes separately and their morphologies were evaluated by six doctors. The "optimal fitting alignment" and "3D analysis" functions of the Geomagic Qualify software were carried out between original teeth and auto-generated full crowns. The auto-generated crowns were modified by a technician according to clinical criteria and the adjustment time was recorded. The discrepancies between technician modified crowns and the auto-generated full crowns were evaluated with the same functions in the Geomagic Qualify software. RESULTS: The subjective evaluation results of BC group were significantly better than those of BI and BR group (p < 0.05). Compared with the original teeth and modified crowns, auto-generated crowns in BC group all had the smallest differences, followed by BR and BI group (p < 0.05). BC group needed the shortest adjustment time than BI and BR group (p < 0.05). CONCLUSIONS: Using crowns generated by BC mode is more aesthetic and suitable in clinics use than those generated by BI and BR modes and can reduce clinic adjustment time.


Asunto(s)
Cerámica , Coronas/normas , Diseño de Prótesis Dental/normas , Automatización , Porcelana Dental , Diseño de Prótesis Dental/métodos , Humanos , Incisivo , Programas Informáticos , Factores de Tiempo
5.
Niger J Clin Pract ; 23(1): 1-6, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31929199

RESUMEN

Objective: The aim of this study was to evaluate the marginal adaptation and fracture resistance of feldspathic and Polymer-Infiltrated Ceramic Network (PICN) CAD/CAM endocrowns for maxillary premolars. Materials and Methods: Twenty extracted human permanent maxillary premolars were randomly divided into two groups (n = 10); Group CEREC (GC), which was produced by feldspathic ceramic and the Group Enamic (GE), which was produced by PICN. All teeth were endodontically treated and decoronated horizontally at 2 mm above the cemento-enamel junction. Endocrown preparations were done with 4 mm depth into the pulp chamber. Endocrowns were manufactured using CAD/CAM from ceramic blocks. Following adhesive cementation, all specimens were subjected to thermocycling. Marginal adaptation evaluated under SEM at 200 × magnification. Each specimen was fixed in a universal testing machine and a compressive load was applied at 45° to long axis of the teeth until failure. Failure load was recorded and failure modes were evaluated. Statistical analyses were performed with SPSS 19.0 software and data were compared using Mann-Whitney U test. Results: There were no significant differences in the marginal adaptation between two groups (P > 0.05). GE presented significantly higher fracture resistance when compared to GC (P < 0.05). Failure pattern was similar and characterized by the tooth-ceramic fracture on the force-applied side. Conclusions: CAD/CAM fabricated feldspathic ceramic and PICN endocrowns provide sufficient marginal adaptation, but the PICN endocrowns shows higher fracture resistance than the feldspathic ceramic endocrowns.


Asunto(s)
Diente Premolar/fisiopatología , Cerámica/química , Coronas , Porcelana Dental/química , Diseño de Prótesis Dental/métodos , Polímeros , Fracturas de los Dientes/fisiopatología , Diseño Asistido por Computadora , Preparación de la Cavidad Dental/métodos , Porcelana Dental/uso terapéutico , Diseño de Prótesis Dental/efectos adversos , Fracaso de la Restauración Dental , Análisis del Estrés Dental , Humanos , Ensayo de Materiales , Cementos de Resina , Estrés Mecánico , Cuello del Diente/lesiones
6.
Med Sci Monit ; 26: e918529, 2020 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-31896741

RESUMEN

BACKGROUND The aim of this study was to evaluate the precision of correlation between intraoral scanners and computer aided design (CAD) software programs used during scanning and designing phases of digital dentistry. In the present study, CAD software programs that accept data in Standard Tessellation Language (STL) and proprietary format have been evaluated and data loss has been examined in the scanned data. MATERIAL AND METHODS A single unit crown preparation was conducted for maxillary right first molar on a fully dentulous model. The prepared tooth was scanned with a high precision industrial scanner (ATOS Core 80) and the reference digital model was obtained. The dental model was further scanned 10 times using 3 different intraoral scanners (CEREC Omnicam AC, TRIOS 3 Color Pod, and Aadva IOS 100). The data obtained from the reference scanner and intraoral scanners were transferred to different CAD programs (CEREC inLab, TRIOS Design Studio, Exocad) and digital crowns were designed for each scanned data-CAD combination. After that, the data losses that occurred between these transfers were evaluated by superimposition technique in a special software (VR Mesh v7.5) (alpha=0.05). RESULTS Among the all combinations of scanner and software, Omnicam AC-InLab was determined to be the most precise combination through the full digital workflow since the Omnicam AC-Exocad combination showed the highest deviations. CONCLUSIONS Within the limitations of this in vitro study, it was determined that the combinations of scanners and associated CAD programs yielded more accurate results, and data loss was revealed when the scanned data converted from the proprietary format to the STL format.


Asunto(s)
Diseño de Prótesis Dental/métodos , Odontología/métodos , Imagenología Tridimensional/métodos , Cerámica , Diseño Asistido por Computadora/tendencias , Coronas , Modelos Dentales , Humanos , Programas Informáticos
7.
Ann Ital Chir ; 82019 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-31527308

RESUMEN

BACKGROUND: Modern cone beam computed tomography (CBCT) acquisition and three-dimensional (3D) image processing, combined with direct metal laser sintering (DMLS), allows custom-made, root-analogue implants (RAIs). PURPOSE: To demonstrate how DMLS permits customized titanium RAI production, with immediate insertion and restoration in a fresh extraction socket of the anterior maxilla. MATERIALS AND METHODS: A titanium RAI perfect copy of the radicular unit needed for replacement was created by customized DMLS, and inserted into a fresh extraction socket of the esthetic area of the anterior maxilla. RESULTS: Follow-up after 1 year: the DMLS RAI implant showed a satisfactory functional and esthetic integration, with no bone resorption or soft tissue recessions. CONCLUSIONS: The production of customized DMLS RAIs opens new interesting perspectives for immediate implantation. KEY WORDS: Direct metal laser sintering, Root analogue implant.


Asunto(s)
Diseño Asistido por Computadora , Tomografía Computarizada de Haz Cónico , Diseño de Implante Dental-Pilar , Implantes Dentales de Diente Único , Diseño de Prótesis Dental/métodos , Carga Inmediata del Implante Dental , Incisivo/lesiones , Metalurgia/métodos , Fracturas de los Dientes/cirugía , Raíz del Diente/lesiones , Diseño Asistido por Computadora/instrumentación , Diseño de Prótesis Dental/instrumentación , Estética , Humanos , Imagenología Tridimensional , Rayos Láser , Masculino , Maxilar , Metalurgia/instrumentación , Persona de Mediana Edad , Titanio
8.
Biomed Res Int ; 2019: 1680158, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31321229

RESUMEN

Introduction: Dental aplasia is an anomaly in which the number of teeth is reduced. It is the most commonly occurring dental anomaly during tooth development. Treatment management of patients with dental aplasia is challenging. Objectives: The aim of this retrospective clinical study was to analyze the survival and success rates of dental implants placed in hypodontic patients, rated with different criteria. Methods: Forty-three patients were diagnosed with dental aplasia and treated with dental implants between November 2000 and February 2016. The variables assessed included the plaque level, bleeding on probing, probing depth, implant mobility, implant stability, and implant loss. To analyze the peri-implant bone level, a panoramic X-ray of each patient was taken. The results were compared with X-rays taken immediately after implantation. Results: Thirty-seven patients (16 males; 21 females) participated in this study. In total, 155 implants (86 maxillary; 69 mandibular) were inserted. Two of the 155 implants failed; the in situ survival rate was 98.7%. The success rate according to the criteria of Buser et al. was 96.8%, and that according to the criteria of Albrektsson et al. was 88.4%. Conclusion: The survival and success rates of dental implants in patients with congenitally absent teeth were very high and did not differ significantly from results achieved in an unaffected population. Dental implants are a reliable therapy for patients with dental aplasia.


Asunto(s)
Pérdida de Hueso Alveolar/prevención & control , Implantación Dental Endoósea/métodos , Implantes Dentales de Diente Único , Implantes Dentales , Adulto , Anciano , Pérdida de Hueso Alveolar/fisiopatología , Diseño de Prótesis Dental/métodos , Femenino , Humanos , Masculino , Mandíbula/fisiopatología , Maxilar/fisiopatología , Persona de Mediana Edad
9.
J Mater Sci Mater Med ; 30(8): 90, 2019 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-31346767

RESUMEN

The aim of this study was to evaluate the biomechanical behavior of Bone Level dental implants with four different neck designs in contact with cortical bone. Numerical simulations were performed using a Finite Element Method (FEM) based-model. In order to verify the FEM model, the in silico results were compared with the results obtained from histological analysis performed in an in vivo study with New Zealand rabbits. FEM was performed using a computerized 3D model of Bone Level dental implants inserted in the lower jaw bone with an applied axial load of 100 N. The analysis was performed using four different implant neck designs: even surfaced, screwed, three-ring design and four-ring design. Interface are of bone growth was evaluated by analyzing the Bone-Implant-Contact (BIC) parameter obtained from in vivo histological process and analyzed by Scanning Electron Microscopy (SEM). Bone Level implants were inserted in the rabbit tibia, placing two implants per tibia. The BIC was evaluated after three and six weeks of implantation. FEM studies showed that the three-ring design presented lower values of stress distribution compared to the other studied designs. The lower levels of mechanical stress were then correlated with the in vivo studies, showing that the three-ring design presented the highest BIC value after 3 and 6 weeks of implantation. In silico and in vivo results both concluded that the implants with three-ring neck design presented the best biomechanical and histological behavior in terms of new bone formation, enhanced mechanical stability and optimum osseointegration.


Asunto(s)
Implantes Dentales , Diseño de Prótesis Dental , Ensayo de Materiales/métodos , Animales , Tornillos Óseos , Calibración , Implantación Dental Endoósea/instrumentación , Implantes Dentales/normas , Diseño de Prótesis Dental/métodos , Diseño de Prótesis Dental/normas , Análisis de Elementos Finitos , Mandíbula/cirugía , Oseointegración/fisiología , Conejos , Estrés Mecánico , Tibia/cirugía
10.
Niger J Clin Pract ; 22(6): 812-816, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31187767

RESUMEN

Aim: The purpose of this study was to compare the marginal and internal fit of Co-Cr and titanium ceramic crowns fabricated with 2 different techniques: CAD/CAM milling and traditional casting (TC). Materials and Methods: Ten traditional casting of Co-Cr (TCC), 10 CAD/CAM milling of Co-Cr (MC), 10 traditional casting of titanium (TCT), 10 CAD/CAM milling of titanium ceramic crowns (MT) were fabricated. Silicone replicas were obtained to measure internal gap volume, marginal gap and internal adaptation that was evaluated at 3 regions: axial wall, axio-occlusal angle, and occlusal surface. Measurements were made with a X-ray micro computerized tomography (micro-CT) and analyzed with Bonferroni and Dunnet T3 post-hoc tests (α = 0.05). Results: One-way ANOVA revealed no statistically significant differences among the groups for measurements at the marginal gap (P > 0.05). At axial wall region the mean values of TCT group were higher than those of groups but only statistically not significant for TCC group (P < 0.05). TCC group statistically gives better results than MC group in axio-occlusal and occlusal regions (P < 0.05). The mean measurement of internal gap volume were 20.59 ± 0.83 mm3 for TCC, 22.73 ± 0.82 mm3 for MC, 22.83 ± 1.11 mm3 for TCT and 20.51 ± 1.16 mm3 for MT. Mean internal gap volume values MT group were smaller than those of groups but only statistically not significant for TCC group (P > 0.05). Conclusion: All groups performed similar marginal adaptation. The cement film thickness at axio-occlusal angle point and occlusal region were higher for MC crowns.


Asunto(s)
Cerámica , Adaptación Marginal Dental , Diseño de Prótesis Dental/métodos , Aleaciones de Cromo , Cobalto , Diseño Asistido por Computadora , Coronas , Técnicas In Vitro , Péptidos y Proteínas de Señalización Intracelular , Titanio
11.
Oral Maxillofac Surg Clin North Am ; 31(3): 489-496, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31164269

RESUMEN

This article summarizes the accomplishments and knowledge gained over the past 2 decades with respect to immediate dental root analogue implants (RAIs). It discusses how the artificial nature of the present dental implant materials and unnatural shapes cause complications, posing a threat to long-term biointegration, and how RAIs will influence the way that implants are produced. Will an osseointegrated RAI be the optimal immediate replacement for extracted teeth in the future? How will three-dimensional printing be involved in these more biomimetic RAI systems? The present research and developments seem promising and will continue to shape the future of implant prosthodontics.


Asunto(s)
Biomimética , Implantes Dentales , Diseño de Prótesis Dental/métodos , Impresión Tridimensional , Raíz del Diente/diagnóstico por imagen , Materiales Dentales , Humanos , Imagenología Tridimensional , Oseointegración , Raíz del Diente/cirugía
12.
Oral Maxillofac Surg Clin North Am ; 31(3): 399-426, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31253346

RESUMEN

The treatment of completely edentulous or soon-to-be completely edentulous dental arches with complete-arch fixed denture restorations, supported by dental implants, are some of the more complicated patient cases in oral and maxillofacial surgery and prosthodontics. This article discusses the use of digital technologies, computerized tomographic (CT) guided planning software applications, and surgical guides in treating these complex dental implant patient cases. A discussion of the nuances and workflows of different types of treatments are provided. The importance of experience and a multi-disciplinary team approach is emphasized.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales , Prótesis Dental de Soporte Implantado/métodos , Arcada Edéntula , Cirugía Asistida por Computador/normas , Diseño Asistido por Computadora , Diseño de Prótesis Dental/métodos , Dentición , Humanos
13.
Mater Sci Eng C Mater Biol Appl ; 102: 66-74, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31147038

RESUMEN

The purpose of this in vitro study was to measure the vertical, positive-horizontal, and negative-horizontal misfit (VM, PHM, and NHM, respectively) of the zirconia three-element prosthetic framework, fabricated using different methods, and compare them with conventional fabrication methods (lost-wax casting). Furthermore, this study aimed to evaluate the influence of the misfit values on the biomechanical behavior of the 3-unit fixed prosthetic frameworks using three-dimensional finite element analysis (3D-FEA). Forty frameworks (n = 10) were fabricated as follow: G1, Cerec Bluecam; G2, iTero; G3, 3Series; and G4, conventional method. The samples were randomized to measure marginal misfit using a high-precision three-dimensional (3D)-optical microscope. The results were submitted to analysis of variance (ANOVA), with the significance level set at 5%. The mean VM values of each group were used in creating the models by 3D-FEA with the misfit found in optical microscopy. The programs used were the InVesalius, Rhinoceros, SolidWorks, FEMAP and NEiNastran. The von Mises map was plotted for each model. The G4 showed the lowest mean VM value (16.73 µm), followed by G3 (20.71 µm), G2 (21.01 µm), and G1 (41.77 µm) (p < 0.001). G2 was more accurate than G1 (p < 0.05) and similar to G3 (p = 0.319). For PHM, G4 was the most accurate and did not present overextended values. With regard to NHM, the computer-aided design and computer-aided manufacturing (CAD-CAM) systems were more accurate (-61.91 µm) than G4 (-95.36 µm) (p = 0.014). In biomechanical analysis, stress concentration caused by oblique loading is greater than caused by axial loading. In axial loading, G4 was the most favorable while G1 was the least favorable, biomechanically, in oblique loading, similar stress patterns were observed in all the models. The prosthetic screw was the most overloaded structure, but the material did not influence the stress distribution. The misfit prostheses showed a greater degree of stress than the controls (without misfit). The manufacturing method influenced the marginal misfit of the frameworks, with the conventional method being the most accurate and the Cerec Bluecam System (closed system) the least accurate. Biomechanically, fitting prostheses were more favorable than misfit prostheses.


Asunto(s)
Implantes Dentales , Diseño de Prótesis Dental/métodos , Estrés Mecánico , Simulación por Computador , Análisis de Elementos Finitos
14.
BMC Oral Health ; 19(1): 66, 2019 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-31029133

RESUMEN

BACKGROUND: Studies focusing on accuracy of intraoral digital models in the palatal region are scarce. The present study aimed to investigate the influence of different scanning sequences on palatal trueness and to assess deviation and distribution character of trueness in palate. METHODS: Overall, 35 participants accepted three types of procedures to acquire upper digital models. Indirect models digitalised from plaster models were considered as the reference. Two direct digital models were acquired using TRIOS 3 POD intraoral scanners, namely Groups Tr1 and Tr2, wherein intraoral scanning differed in terms of palatal scanning sequences. Based on a modified dental-level superimposition method, 3D measurements of trueness in palate and palatal vault region (PVR) for palatal stable regional superimposition in Groups Tr1 and Tr2, respectively, were performed. Absolute deviations were measured for trueness, while signed deviations were analysed for shape distortion. Colour-coded maps were used for quantitative analysis of deviation distribution pattern. Paired t test was used to analyse differences in palatal trueness between different scanning sequences. One-way repeated-measures analysis of variance and Bonferroni test were used to compare trueness measurements among different superimposition methods. Intraclass correlation coefficient (ICC) was used to verify reproducibility of the proposed method. RESULTS: Palatal trueness in Group Tr1 (118.59 ± 37.67 µm) was slightly less accurate than that (108.25 ± 33.83 µm) in Group Tr2 (p = 0.012 < 0.05). Trueness of PVR in Groups Tr1 (127.35 ± 54.11 µm) and Tr2 (118.17 ± 49.52 µm) did not differ significantly (p = 0.149). Moreover, no significant difference was noted in distortion of the palatal region and PVR in Groups Tr1 and Tr2 (p = 0.582 and 0.615, respectively). A similar pattern of palatal trueness was noted in a majority of participants (22/35). For 3D palatal trueness measurement, there were different applications for different superimposition methods. ICC for the proposed method was > 0.90. CONCLUSIONS: Scanning sequences can affect palatal trueness. Palatal scanning should be initiated at the palatal side of the posterior teeth where the initial scan begins. For 3D PVR superimposition, distal boundary of the selected region should be adjusted mesially whilst referring to intraoral digital models. TRIAL REGISTRATION: The trial has been registered (registration No: R000039467 , Trial ID: UMIN000034617, date of registration: 2018/10/24'retrospectively registered').


Asunto(s)
Arco Dental/anatomía & histología , Arco Dental/diagnóstico por imagen , Materiales de Impresión Dental , Técnica de Impresión Dental , Diseño de Prótesis Dental/métodos , Procesamiento de Imagen Asistido por Computador/instrumentación , Paladar (Hueso)/anatomía & histología , Diseño Asistido por Computadora , Modelos Dentales , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Reproducibilidad de los Resultados , Estudios Retrospectivos
15.
Indian J Dent Res ; 30(1): 127-129, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30900671

RESUMEN

Objective: This study aimed to evaluate the marginal fit of zirconia and lithium disilicate ceramic restorations processed by computer-aided design (CAD)/computer-aided manufacturing (CAM) system. Materials and Methods: Ten models were prepared from a metal die, on which scanning was carried out to obtain the virtual model for the processing of zirconia and lithium disilicate ceramics using the CAD/CAM technique. Gypsum models were fabricated and used for scanning the restorations. The infrastructures were designed using software, and CAD/CAM was used to fabricate the restorations (n = 10). The analysis of the marginal discrepancy was measured at 12 points of the margin using the original metallic die. For each crown, an arithmetic average of the discrepancy values was obtained. Results: The marginal fit of the copings of lithium disilicate was 133.10 ± 26.87 µm and zirconia was 127.34 ± 47.97 µm. There was no statistically significant difference (P = 0.7709) between the materials. Conclusion: The marginal fit is similar between lithium disilicate and zirconia ceramics milled in the CAD/CAM system used.


Asunto(s)
Cerámica , Diseño Asistido por Computadora , Coronas , Adaptación Marginal Dental , Materiales Dentales , Porcelana Dental , Diseño de Prótesis Dental/métodos , Circonio , Modelos Dentales , Humanos , Programas Informáticos
16.
Mater Sci Eng C Mater Biol Appl ; 98: 1294-1305, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30813009

RESUMEN

BACKGROUND: Zirconia has emerged as a versatile dental material due to its excellent aesthetic outcomes such as color and opacity, unique mechanical properties that can mimic the appearance of natural teeth and decrease peri-implant inflammatory reactions. OBJECTIVE: The aim of this review was to critically explore the state of art of zirconia surface treatment to enhance the biological and osseointegration behavior of zirconia in implant dentistry. MATERIALS AND METHODS: An electronic search in PubMed database was carried out until May 2018 using the following combination of key words and MeSH terms without time periods: "zirconia surface treatment" or "zirconia surface modification" or "zirconia coating" and "osseointegration" or "biological properties" or "bioactivity" or "functionally graded properties". RESULTS: Previous studies have reported the influence of zirconia-based implant surface on the adhesion, proliferation, and differentiation of osteoblast and fibroblasts at the implant to bone interface during the osseointegration process. A large number of physicochemical methods have been used to change the implant surfaces and therefore to improve the early and late bone-to-implant integration, namely: acid etching, gritblasting, laser treatment, UV light, CVD, and PVD. The development of coatings composed of silica, magnesium, graphene, dopamine, and bioactive molecules has been assessed although the development of a functionally graded material for implants has shown encouraging mechanical and biological behavior. CONCLUSION: Modified zirconia surfaces clearly demonstrate faster osseointegration than that on untreated surfaces. However, there is no consensus regarding the surface treatment and consequent morphological aspects of the surfaces to enhance osseointegration.


Asunto(s)
Materiales Dentales/química , Propiedades de Superficie/efectos de los fármacos , Circonio/química , Animales , Implantes Dentales , Diseño de Prótesis Dental/métodos , Humanos , Oseointegración/efectos de los fármacos
17.
Clinics (Sao Paulo) ; 74: e852, 2019 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-30916212

RESUMEN

OBJECTIVES: To evaluate and compare the magnitude and distribution of stresses generated on implants, abutments and first molar metal-ceramic crowns using finite element analysis. METHODS: Preliminary three-dimensional models were created using the computer-aided design software SolidWorks. Stress and strain values were observed for two distinct virtual models: model 1 - Morse taper and solid abutment; model 2 - Morse taper and abutment with screw. A load (250 N) was applied to a single point of the occlusal surface at 15° to the implant long axis. Von Mises stresses were recorded for both groups at four main points: 1) abutment-retaining screws; 2) abutment neck; 3) cervical bone area; 4) implant neck. RESULTS AND CONCLUSION: Model 1 showed a higher stress value (1477.5 MPa) at the abutment-retaining screw area than the stresses found in model 2 (1091.1 MPa for the same area). The cervical bone strain values did not exceed 105 µm for either model.


Asunto(s)
Diseño de Implante Dental-Pilar/instrumentación , Implantes Dentales , Diseño de Prótesis Dental/instrumentación , Análisis del Estrés Dental , Análisis de Elementos Finitos , Diseño Asistido por Computadora , Coronas , Diseño de Implante Dental-Pilar/métodos , Diseño de Prótesis Dental/métodos , Módulo de Elasticidad , Humanos , Mandíbula/diagnóstico por imagen , Modelos Anatómicos , Estrés Mecánico
18.
Int J Oral Maxillofac Implants ; 34(3): 698­707, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30892285

RESUMEN

PURPOSE: The objective was to measure the implant prosthodontic discrepancy of complete-arch implant-supported frameworks made of cobalt-chromium (Co-Cr) fabricated using selective laser melting (SLM) additive manufacturing technologies. MATERIALS AND METHODS: A completely edentulous maxillary cast with seven implant replicas was obtained. Co-Cr SLM frameworks (n = 9) from three different providers (SLM-1, SLM-2, SLM-3) were manufactured. A coordinate measuring machine was selected to measure the implant prosthodontic discrepancy (µm) on the x-, y-, and z-axis and the 3D gap (3D = √x2+ y2+z2) where implants were considered as the statistical unit (n = 7). One-way analysis of variance (ANOVA), Student-Newman-Keuls, and Tukey tests were used to analyze the data (α = .05). RESULTS: The mean 3D implant prosthodontic discrepancy (µm) was higher for SLM-1 (73.77 ± 27.94) than for SLM-2 (47.54 ± 22.63) and SLM-3 (47.26 ± 22.57). At the x-axis, SLM-2 showed a significantly smaller gap (16.21 ± 9.6) than SLM-3 (32.92 ± 27.77) and SLM-1 (34.77 ± 21.85). At the y-axis, however, SLM-3 presented a significantly smaller gap (27.97 ± 9.49) than SLM-2 (38.84 ± 27.82) and SLM-1 (54.35 ± 29.89). Similarly, at the z-axis, SLM-3 (4.01 ± 2.29) showed the least gap, followed by SLM-2 (9.09 ± 7.63), being significantly smaller than that of SLM-1 (16.14 ± 21.09). CONCLUSION: The three SLM additive manufacturing technologies tested showed implant prosthodontic discrepancies ranging from 4.01 to 54.35 µm, which could be considered in the clinically acceptable range. Distortion at the z-axis was significantly less compared to x- and y-axes in all the groups tested.


Asunto(s)
Cromo/química , Cobalto/química , Diseño de Prótesis Dental/métodos , Prótesis Dental de Soporte Implantado , Análisis de Varianza , Aleaciones de Cromo , Diseño Asistido por Computadora , Adaptación Marginal Dental , Prótesis Dental de Soporte Implantado/normas , Humanos , Rayos Láser
19.
Artículo en Inglés | MEDLINE | ID: mdl-30754648

RESUMEN

(1) Background: Three-dimensional printing is progressing rapidly and is applied in many fields of dentistry. Tooth autotransplantation offers a viable biological approach to tooth replacement in children and adolescents. Restoring or reshaping the transplanted tooth to the anterior maxilla should be done as soon as possible for psychological and aesthetic reasons. However, to avoid interfering with the natural healing process, reshaping of transplanted teeth is usually delayed three to four months after transplantation. This delay creates a need for simple indirect temporary aesthetic restoration for autotransplanted teeth. The aim of this study was to develop and validate a digital solution for temporary restoration of autotransplanted teeth using 3D printing. (2) Methods: Four dry human skulls and four dry human mandibles were scanned using cone beam computed tomography to create 3D models for 15 premolars. Digital impression of the maxillary arch of one of the skulls was captured by intra oral scanner. The digital work flow for the design and fabrication of temporary veneers is presented. The seating and adaptation of the 3D printed veneers were evaluated using stereomicroscopy and micro-computed tomography. (3) Results: Evaluation of the veneer seating using stereomicroscopy showed that the mean marginal gap at all of the sides was below the cut-off value of 200 µm. The overall mean marginal gap was 99.9 ± 50.7 µm (median: 87.8 (IQR 64.2⁻133 µm)). The internal adaptation evaluation using micro-computed tomography showed an average median gap thickness of 152.5 ± 47.7 (IQR 129⁻149.3 µm). (4) Conclusions: The present concept of using temporary veneers that are designed and fabricated with CAD/CAM (computer-aided design/computer-aided manufacturing) technology using a DLP (digital light processing) printer may present a viable treatment option for restoration of autotransplanted teeth.


Asunto(s)
Autoinjertos , Diseño Asistido por Computadora , Diseño de Prótesis Dental/métodos , Restauración Dental Permanente/métodos , Impresión Tridimensional , Niño , Tomografía Computarizada de Haz Cónico , Humanos , Diente , Microtomografía por Rayos X
20.
Artículo en Inglés | MEDLINE | ID: mdl-30794252

RESUMEN

The aim of this randomized, prospective study was to compare clinical and radiographic outcomes of microtextured implants with two different collar designs at 1 year postplacement. A total of 69 implants were assessed in 58 patients for site, patient-specific, and clinician-experience variables. Overall implant survival was 94.9%. A statistically significant preservation of crestal bone was observed in the microgrooved-collar group. Narrow implant diameter was associated with a statistically significant increase in crestal bone loss. Collar design and implant diameter may be important in limiting adverse esthetic and bone loss outcomes during initial function.


Asunto(s)
Pérdida de Hueso Alveolar/etiología , Implantación Dental Endoósea/métodos , Implantes Dentales/efectos adversos , Diseño de Prótesis Dental/métodos , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/prevención & control , Implantación Dental Endoósea/efectos adversos , Humanos , Estudios Prospectivos , Radiografía Dental , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...