Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.095
Filtrar
1.
Int J Prosthodont ; 33(4): 380-385, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32639697

RESUMEN

PURPOSE: To test the accuracies of different methods of digital vertical dimension augmentation (VDA) by comparison with a clinical situation. MATERIALS AND METHODS: Bite registrations with approximately 5 mm of VDA were made in the incisor regions of 10 subjects (mean VDA 4.5 mm). The conventional maxillary and mandibular stone casts in maximum intercuspation (MICP) and VDA bite registrations were digitized for all subjects using a laboratory scanner (control group). Lateral portraits were taken of all subjects to locate the position of the condylar axis. Four different digital VDA methods were compared to the control group: 100% rotation of the mandible referring to the lateral picture (100RL); 85% rotation and 15% translation referring to the lateral picture (85R15TL); 100% rotation in normal mounting mode of the Trios virtual articulator (100R); and jaw-motion analysis (JMA) equipment. The amount of VDA for each experimental group was compared to the control group. The augmented distances between the central incisors and the second molars were measured using 3D analyzing software. The ratio of the augmented distances between the posterior and anterior regions (P/A ratio) was calculated. One-way analysis of variance and multiple comparisons via least significant difference test were carried out to determine statistical significance. RESULTS: The P/A ratio of each group was as follows: Control = 0.61; 100RL = 0.55; 85R15TL = 0.61; 100R = 0.53; JMA = 0.52. Significant differences were observed for control vs JMA and for 85R15TL vs JMA (P < .05). The addition of translational movement was the primary factor for increasing the accuracy of digital VDA, with the lateral picture being a secondary factor. CONCLUSION: VDA using a virtual articulator with 100% rotation induces an error when compared to the clinical situation. When a clinician performs digital VDA, the setting of 85% rotation and 15% translation produces results closer to the real clinical condition.


Asunto(s)
Articuladores Dentales , Modelos Dentales , Registro de la Relación Maxilomandibular , Mandíbula , Proyectos Piloto , Dimensión Vertical
2.
Int J Prosthodont ; 33(4): 441-451, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32639704

RESUMEN

PURPOSE: To research and develop a novel virtual articulator system (the PN-300) based on computer binocular vision, raster scanning, and simulation technology and to conduct a preliminary evaluation of its accuracy. MATERIALS AND METHODS: Two digital cameras were used to build the trajectory-tracking part of the virtual articulator system, and cameras combined with a projection module were used to form the scanning part of the system. The most prominent feature of the PN-300 is its ability to simultaneously obtain the 3D data of the subject's teeth and the movement trajectory of the mandible relative to the maxilla. The PN-300 recorded the linear, circular, and rectangular quadrilateral movements of a high-accuracy 3D electronic translation stage. The accuracy of measurement of the inclination of incisal guidance derived from the PN-300 based on the PROTAR evo7 articulator was also estimated. RESULTS: The measurement error was below 100 µm for the linear and circular movements, and the angle error was within 0.2 degrees for the rectangular quadrilateral movements. The error of inclination of protrusive incisal guidance was 1.51 ± 0.68 degrees, and for incisal guidance was 0.82 ± 0.55 degrees. Trajectories and incisal 3D data obtained by the PN-300 were combined with data from plaster models and CBCT to simulate mandibular movement and to calculate the trajectories of the condyle. CONCLUSION: The PN-300 achieved a good accuracy for recording mandibular movement and can be expected to calculate the movement of the condyle.


Asunto(s)
Articuladores Dentales , Dentición , Mandíbula , Maxilar , Movimiento
3.
Int J Comput Dent ; 23(1): 39-48, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32207460

RESUMEN

BACKGROUND: The Dental Motion Decoder system (DMS-System) is a medical device based on magnetic field technology that records mandible movements. The data can be used to program an articulator or can be directly processed over a computer-aided design (CAD) interface. The present study aimed to assess the reproducibility of this system in vitro and in vivo. MATERIAL AND METHODS: Protrusive and laterotrusive movements were simulated in vitro using an articulator (SAM SE) (Group M) and in vivo (Group P) on one test individual. Measurements were carried out in two ways: 1) Measurements were taken after initializing and referencing the system using the reference points (RPs) once, followed by 30 protrusive and laterotrusive movements (M1 and P1); and 2) Thirty individual measurements were recorded using the RPs before each measurement (M2 and P2). Values for the sagittal condylar path inclination angle (sCPIA) and the Bennett angle (BA) were exported and analyzed. The reproducibility of the system was evaluated using the standard deviations (SDs) of the measurement series (sCPIA and BA for M1, M2, P1, and P2). RESULTS: In vitro tests M1 (SD: sCPIA = 0.08 degrees; BA = 0.06 degrees) and M2 (SD: sCPIA = 0.26 degrees; BA = 0.11 degrees) showed significantly higher reproducibility (P < 0.001) compared with the in vivo measurements P1 (SD: sCPIA = 0.61 degrees; BA = 0.45 degrees) and P2 (SD: sCPIA = 1.4 degrees; BA = 0.65 degrees). CONCLUSION: Within the limitations of the present study, the deviation in vitro, representing the reproducibility of the DMD-System, is smaller than the biologic variance observed in vivo. Therefore, reliable measurements under clinical conditions can be assumed.


Asunto(s)
Articuladores Dentales , Cóndilo Mandibular , Humanos , Registro de la Relación Maxilomandibular , Imanes , Movimiento , Reproducibilidad de los Resultados
4.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(1): 138-143, 2020 Feb 18.
Artículo en Chino | MEDLINE | ID: mdl-32071477

RESUMEN

OBJECTIVE: To evaluate the three-dimensional (3D) reconstruction accuracy of the intercuspal occlusion (ICO) of the dental casts, by the dental articulator position method, and provide a reference for clinical application. METHODS: The standard dental casts in ICO were mounted on average values articulator, and five pairs of milling resin cylinders were respectively attached to the base of both the casts. 100 µm articulating paper and occlusal record silicone rubber were used to detect the occlusal contact number between the posterior teeth of casts mounted on articulator in ICO. The occlusal contact numbers NA detected by the two methods were calculated simultaneously, as the reference. After the upper and lower casts were scanned separately, and the buccal data of casts in ICO were scanned with the aid of the dental articulator position, registration was carried out utilizing the registration software. Then the digital casts mounted in ICO as well as the buccal occlusal data were saved in standard tessellation language (STL) format. Geomagic Studio 2013 software was used to analyze the contact number NS between digital upper and lower casts by the "deviation analysis" function. The differences were compared between NS and NA, to evaluate the sensitivity and positive predict value (PPV) of the model scanner to reproduce the occlusal contact with the aid of dental articulator position. The distance DR between the centers of the circles at the top surface of the upper and lower corresponding cylinders was obtained by the three-coordinate measuring system Faro Edge, as the reference value. The Geomagic Studio 2013 software was used to construct the cylinders of digital casts and the distance DM between the centers of the circles at the top surface of the corresponding cylinders were measured, as the test value. The one-sample T test was used to analyze the variable differences between DM and DR. RESULTS: The PPV of reproducing the occlusal contact point was 0.76 and sensitivity was 0.81. The distance error of the opposite cylinder was (0.232±0.089) mm. There was no statistical difference between the feature points 5-5', while there were statistical differences between the other feature points. CONCLUSION: By the dental articulator position method, the model scanner reproduces the occlusal contact point with high sensitivity and PPV, and that meets clinical needs. Meanwhile, the distance between the feature points is greater than the reference value, which will lead to occlusal disturbance, and require clinical grinding.


Asunto(s)
Articuladores Dentales , Modelos Dentales , Oclusión Dental , Imagenología Tridimensional , Registro de la Relación Maxilomandibular , Programas Informáticos
5.
J Prosthodont ; 29(2): 185-189, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31919939

RESUMEN

The articulator is a prerequisite device for the analysis of occlusion and prosthodontic treatment, and it is required to simulate patient jaw movements. This article describes the technique to obtain sagittal condylar inclination (SCI) using cone beam computed tomography (CBCT) data and intraoral scan of the protrusive interocclusal position. The SCI can be used on a virtual articulator in a computer-aided design software, and it can assist in the fabrication of prosthesis which is harmonious with the mandibular movement of individual patient.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Articuladores Dentales , Diseño Asistido por Computadora , Oclusión Dental , Humanos , Imagenología Tridimensional , Registro de la Relación Maxilomandibular , Mandíbula , Cóndilo Mandibular
6.
J Prosthet Dent ; 123(2): 299-304, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31227235

RESUMEN

STATEMENT OF PROBLEM: The optimal procedure for the transfer of the sagittal inclination of the occlusal plane (OP) to semiadjustable and fully adjustable articulators is unclear. PURPOSE: The purpose of this clinical study was to evaluate and compare the sagittal inclination of the OP with the Frankfort horizontal plane (FHP) on a facebow transfer to semiadjustable and fully adjustable articulators. MATERIAL AND METHODS: Facebow transfers (Hanau Spring-Bow; Whip Mix Corp) of 30 participants were recorded and transferred to a semiadjustable articulator (Hanau Wide-Vue; Whip Mix Corp) using the indirect method. Another set of facebow transfers from the same set of 30 participants using another facebow (Denar Slidematic Facebow; Whip Mix Corp) was recorded and transferred to a fully adjustable articulator (Denar D5A; Whip Mix Corp). The angle between the OP of the mounted cast and the upper member of the articulator was measured in each participant with a digital protractor on both articulators. Standardized lateral cephalograms of each participant were made as a control. The FHP and OP were traced on each standardized lateral cephalogram. The angle on the cephalogram between the FHP and OP was measured. These values were compared with previously measured values for the Hanau Wide-Vue and the Denar D5A articulators. The data were analyzed using ANOVA. Intergroup comparisons between and among the Hanau Wide-Vue, Denar D5A, and lateral cephalograms were performed using the independent t test. RESULTS: No statistically significant difference was found between the Hanau Wide-Vue and Denar D5A articulators compared with the lateral cephalograms (P=.06). In the intergroup comparison, no statistically significant differences were found between the Hanau Wide-Vue and Denar D5A articulators (P=.18). No statistically significant differences were found between the values obtained on the Hanau Wide-Vue and lateral cephalograms (P=.06). When the Denar D5A articulator was compared with the lateral cephalograms, there was a statistically significant difference (P=.02). CONCLUSIONS: The Hanau Wide-Vue articulator most closely replicated the inclination of the OP. Regarding the sagittal inclination of the OP, the semiadjustable articulator can provide more accurate results than a fully adjustable articulator and thus eliminates occlusal errors.


Asunto(s)
Articuladores Dentales , Oclusión Dental , Aparatos de Tracción Extraoral , Cabeza , Humanos , Registro de la Relación Maxilomandibular
7.
J Prosthet Dent ; 123(2): 305-313, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31227241

RESUMEN

STATEMENT OF PROBLEM: Complex digital workflows have been developed to create virtual dental patients. Direct and indirect digital methods are available for transferring analog patient information to virtual articulators. The direct method consists solely of digital workflows. The indirect method combines analog steps and digital procedures, representing an intermediate solution between the analog and direct digital approach. Studies that have investigated the overall accuracy of the virtual working space are sparse. PURPOSE: The purpose of this clinical study was to investigate the accuracy of the virtual dental space using the indirect digital workflow. MATERIAL AND METHODS: Mounted gypsum casts of 18 patients were used for indirect scanning. The maxillary casts were mounted in their skull-related position with a kinematic facebow. The mandibular casts were mounted in centric relation to the maxillary casts. The obtained digitized casts were transferred to a virtual articulator. An occlusal analysis was performed both in the analog and virtual environments, and the coordinates of matching analog and virtual contact points were measured. The trueness and precision of the indirect transferring procedure were assessed. RESULTS: A total of 194 analog points was considered in the reference. Ninety-three percent of all analog points matched a virtual correspondent, and 96% of the analog first contacts between the casts were also present as first contacts in the virtual space. The trueness of the data transfer, corresponding to the spatial distance between the matching analog and virtual points, was 0.55 ±0.31 mm. The maximum recorded deviation was 1.02 mm. CONCLUSIONS: The correspondence between the number and position of analog and virtual contacts was high. The mean absolute deviation of the matching point-pairs was better than that reported for the direct digital method. Under the conditions described, the virtual dental space created with the indirect digital method can be reliably used for virtual occlusal analysis in clinical practice.


Asunto(s)
Articuladores Dentales , Modelos Dentales , Humanos , Registro de la Relación Maxilomandibular , Mandíbula , Maxilar
8.
Prim Dent J ; 8(3): 40-47, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31666172

RESUMEN

An accurate interocclusal record is essential for the successful delivery of fixed prosthodontic restorations. There are various materials and techniques used to obtain an interocclusal record in order to facilitate mounting of the dental casts on an articulator. The interocclusal record describes the vertical and horizontal relationship of the maxillary and mandibular teeth. In circumstances where the vertical relationship is not supported through a tripod of widely spaced opposing contacts, the interocclusal record will be needed to restore this vertical support to prevent inaccurate mounting. The clinician should understand when an interocclusal record is required and have an awareness of the different materials and techniques available to record an interocclusal registration.


Asunto(s)
Articuladores Dentales , Modelos Dentales , Oclusión Dental , Dentición , Registro de la Relación Maxilomandibular , Arcada Parcialmente Edéntula , Prostodoncia , Atención Odontológica , Diseño de Dentadura , Humanos , Registro de la Relación Maxilomandibular/instrumentación , Registro de la Relación Maxilomandibular/métodos
9.
Br J Oral Maxillofac Surg ; 57(7): 672-677, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31256987

RESUMEN

Occlusal splints are commonly used to position the maxilla during traditional orthognathic surgery. We aimed to quantify the inaccuracy of the maxillary positioning (in three dimensions) in traditional model surgery with the Orthopilot® navigation system. Thirty Le Fort I osteotomies were made using a standard technique. The position of the maxilla was recorded by the navigation system and defined by three values of translation and three of rotation. The recorded data were compared with the planned data. The accuracy of positioning was classified in distinct classes with three major criteria (conformity, non-conformity, and failure) according to the discrepancy. The positioning of the maxilla was in conformity with operative planning in 3/30 of our Le Fort I osteotomies (95% CI 2% to 27%) and in failure in 22/30 (95% CI 54% to 88%). The dispersion of the discrepancy was more important in the sagittal plane, particularly for the sagittal rotation and for the back-front translation, which reflected greater inaccuracy in this plan. The frontal orientation of the maxilla was better controlled. The risk of maxillary malposition was proportional to the planned maxillary advancement.


Asunto(s)
Articuladores Dentales , Imagenología Tridimensional/métodos , Ferulas Oclusales , Procedimientos Quirúrgicos Ortognáticos/métodos , Osteotomía Le Fort , Cefalometría , Humanos , Maxilar , Retrognatismo , Cirugía Asistida por Computador
10.
J Am Dent Assoc ; 150(7): 618-623, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31103133

RESUMEN

BACKGROUND AND OVERVIEW: In this report, the authors describe a combined digital and conventional work flow that enabled placement of immediate dentures in 2 patient visits. CASE DESCRIPTION: Digital intraoral impressions and interarch relationship were obtained with an intraoral scanner during the first visit. The residual teeth from the digital intraoral impressions were removed, and a series of modules were used to design trial denture base and occlusal rim assemblies. The assemblies of both arches were fabricated with a 3-dimensional printer and resin material. Dental stone was poured into the intaglio of each assembly to fabricate dental casts. The assemblies and their corresponding dental casts were mounted on the articulator. The portion of the resin occlusal rim was removed, and the artificial teeth were arranged in an alternating manner; the immediate dentures were processed via conventional protocols. During the second visit, these immediate dentures were placed after extraction and relined with a denture relining material. CONCLUSIONS AND PRACTICAL IMPLICATIONS: Advances in digital technologies have enabled the establishment of treatment plans that would not have been considered previously. The combination of digital and conventional work flow in fabricating immediate dentures has eliminated the risk of experiencing unintentional tooth extraction during impression-making procedures, reduced the number of patient visits for the placement of immediate dentures, and resulted in satisfactory esthetic and functional outcomes.


Asunto(s)
Implantes Dentales , Técnica de Impresión Dental , Diseño Asistido por Computadora , Articuladores Dentales , Bases para Dentadura , Humanos
11.
Rev. ADM ; 76(2): 109-112, mar.-abr. 2019. ilus
Artículo en Español | LILACS | ID: biblio-1009264

RESUMEN

La desprogramación neuromuscular juega un papel importante en el tratamiento de la disfunción temporomandibular, uno de los principales inconvenientes es el periodo prolongado del tratamiento, lo cual influye en la aceptación del paciente o el abandono del tratamiento. El diagnóstico es crucial para planificar el tratamiento ya que cubre una amplia gama de variables para tratarlo, por lo que en este caso es un paciente dolicofacial, con problemas de disfunción temporomandibular de origen muscular, por lo cual se optó por utilizar laserterapia de bajo nivel como coadyuvante de tratamiento, dando como resultado una mejor aceptación y colaboración de la desprogramación del paciente en un periodo de tiempo más corto (AU)


Neuromuscular deprogramming plays an important role in the treatment of temporomandibular dysfunction, one of the main drawbacks is the prolonged period of treatment, which influences the acceptance of the patient or the abandonment of treatment. The diagnosis is crucial to plan the treatment since it covers a wide range of variables to treat it, so in this case it is a dolichofacial patient, with problems of temporomandibular dysfunction of muscular origin, which is why we chose to use low-level laser therapy, level as a coadjutant of treatment, resulting in a better acceptance and collaboration of the deprogramming of the patient in a shorter period of time (AU)


Asunto(s)
Humanos , Masculino , Adolescente , Síndrome de la Disfunción de Articulación Temporomandibular/terapia , Oclusión Dental Céntrica , Láseres de Semiconductores/uso terapéutico , Ferulas Oclusales , Articuladores Dentales , México
13.
J Oral Rehabil ; 46(5): 468-474, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30702766

RESUMEN

BACKGROUND: Some occlusal detection products are designed for use on dry teeth, but this is not always achieved. Others are suited for dry and wet applications. OBJECTIVE: The objective of this study is to assess the combined effects, on occlusal contact forces, of two previously studied affecting variables-occlusal detection products and saliva. METHODS: We used a full-arch dentiform with three occlusal detection products (an articulating film, an articulation paper and T-Scan) in combination with human (HS) and an artificial saliva. The maxillary arch assembly, weighing ~54 N (the maximum bite force), was lowered onto (occlusion) and lifted off (disclusion) of the mandibular arch through 10 cycles by a mechanical testing machine. The forces and moments acting on the mandibular arch were continuously recorded by a load cell that supported it. RESULTS: The maximum values of Flateral (the in-occlusal plane component of the occlusal contact force) were analysed by occlusion/disclusion separately using one-way ANOVA, with factor for group type to identify the significant effect of salivas on products, effect of products, effect of salivas with products, effect of human saliva. A difference in occlusion and/or in disclusion was considered different. Statistical differences (P < 0.0001) in Flateral were found in: dry product vs product + HS, dry product vs product + artificial saliva (with articulating film and T-Scan) and HS vs product + HS (with articulation paper and T-Scan). CONCLUSION: All products were affected by the salivas, except articulation paper by artificial saliva.


Asunto(s)
Fuerza de la Mordida , Articuladores Dentales , Análisis del Estrés Dental/instrumentación , Saliva/química , Análisis de Varianza , Fenómenos Biomecánicos , Modelos Dentales , Humanos , Registro de la Relación Maxilomandibular/métodos , Reproducibilidad de los Resultados , Estrés Mecánico , Propiedades de Superficie
14.
J Prosthodont ; 28(4): 436-443, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30737975

RESUMEN

PURPOSE: To study the effects of altering condylar settings and pin openings on the trueness and precision of virtual articulators vs. mechanical articulators. MATERIALS AND METHODS: Maxillary and mandibular typodonts with fiducial markers were mounted on a mechanical Artex-CR articulator, and the mandibular teeth were prepared to allow guidance solely by the posterior determinants of the articulator and the incisal table. The relationship of the mounted typodonts was preserved digitally by scanning using manufacturer transfer plate adaptors. On the mechanical articulator, pattern resin was allowed to set between the maxillary and mandibular occlusal surfaces (area #25-30) at the endpoints of dynamic movements at 3 condylar inclinations (SCI): 10°, 30°, and 45°, n = 12/inclination, or at 3 incisal pin openings (2, 5, and 10 mm, n = 12/opening). All other articulator settings were kept constant. Resin specimens attached to the typodonts were scanned within 5 minutes of setting, then removed, and the articulated typodonts rescanned. Fixed dental prostheses (FDPs) #25-30 were designed on the virtual articulator using identical parameters to the mechanical articulator. Dynamic virtual movements were used to sculpt the design, and a file of the design was saved. The files of both types of samples were aligned and overlaid. Interocclusal separation was measured in triplicate at the indentation created by the mesiolabioincisal point angle on the incisal edge of #8 and the mesiobucco-occlusal point angle of #3. Trueness and precision of both types of articulators were calculated and compared using one-way ANOVA, followed by the Tukey HSD test (α = 0.05). RESULTS: There was no statistically significant difference at altered pin openings in either trueness (F = 0.202, p = 0.37) or precision (F = 3.134, p = 0.09) for the majority of measurements. The only significant difference was in the precision between the 2 types of articulators at 5 mm incisal opening, and only at the anterior measurement point (F = 15.134, p = 0.0008); however, these differences were less than 100 µm. When the SCI was altered, there was no statistically significant difference (F = 3.624, p > 0.05) between the virtual and mechanical articulators in trueness for 5 of the 6 measurements obtained (F = 3.624, p = 0.07) or for all of the precision measurements (F = 3.529, p = 0.07). The one trueness measurement that was significantly different (F = 9.237, p = 0.006) occured at SCI of 10°, and it was less than 100 µm. CONCLUSIONS: Dynamic movements on the virtual articulator were shown to be as true and precise as to the mechanical articulator. When there were deviations, these deviations were less than 100 µm and thus, these deviations may not be clinically relevant.


Asunto(s)
Articuladores Dentales , Diente , Registro de la Relación Maxilomandibular , Mandíbula , Maxilar
15.
J Prosthodont ; 28(3): 335-338, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30663165

RESUMEN

Mounting casts accurately on an articulator is a prerequisite for the treatment planning/execution of complex dental cases that require occlusal rehabilitation. A full digital approach to transfer the position of maxillary dentition to a virtual articulator, by using intraoral scans and cone beam computed tomography (CBCT) files is presented. This technique offers reduced chairside time and the flexibility of choosing the orientation plane. It can be used in orthognathic surgeries, complex interdisciplinary treatments requiring a CBCT scan with a large field of view, or treatments that already have the head CT or CBCT scans from previous diagnosis/treatment.


Asunto(s)
Articuladores Dentales , Imagenología Tridimensional , Tomografía Computarizada de Haz Cónico , Modelos Dentales , Maxilar , Planificación de Atención al Paciente
16.
J Prosthodont ; 28(1): e252-e258, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29136307

RESUMEN

PURPOSE: To study the effects of denture adhesive upon denture micromovements in three dimensions during the chewing of hard, sticky, and tough food items observed using a novel method involving an electromagnetic articulograph (EMA) speech research system. MATERIALS AND METHODS: Ten volunteers (mean age 60.9 ± 10.4 years) with fair- or poor-fitting complete maxillary dentures were enrolled. Chewing experiments were conducted using two treatments (adhesive or no-adhesive control) and three foods: carrots (hard), raisins (sticky), and processed meat stick (tough). Denture micromovement was measured through a novel application of a Northern Digital Wave EMA System. Three-dimensional denture position was captured during mastication using three sensors embedded into a replica denture for each subject. Following individual characterization of a "home" reference position, the Euclidean Distances from Home (DfH) were calculated for each recorded sample of the chewing experiments. The DfH at each sample represented the denture movement for that 1/100th of a second of the activity. The DfH data were then summarized as the mean DfH, the maximum DfH, and total distance traveled by the denture. Several thresholds were also analyzed, including the percent of time that the DfH ≥1.5 mm, ≥2.0 mm, and ≥2.5 mm. RESULTS: With adhesive treatment, the mean DfH of dentures during chewing was reduced by 26.8% for carrot, 30.3% for raisin, and 31.0% for meat stick, when compared with no-adhesive treatment (p < 0.001 for all comparisons). Similar results were also seen for the maximum DfH and total distance travelled endpoints across foods. For the threshold endpoints, adhesive treatment was associated with a statistically significant reduction in denture micromovements at all three thresholds across foods. At the threshold of DfH ≥ 1.5 mm, adhesive treatment was associated with a reduction in micromovement by 61.6%, 56.2%, and 70.0% with carrot, raisin, and meat stick, respectively (p ≤ 0.004 for all comparisons). CONCLUSIONS: Observations of denture movement using the Wave EMA System were able to differentiate systematically between adhesive treatment and no-adhesive treatment for denture micromovements during different chewing challenges. Use of adhesive was associated with statistically significant reductions in denture micromovements for hard, sticky, and tough foods as measured with both distance and threshold endpoints.


Asunto(s)
Articuladores Dentales , Cementos Dentales/química , Fenómenos Electromagnéticos , Masticación/fisiología , Resinas Acrílicas , Anciano , Diseño de Dentadura , Retención de Dentadura , Dentadura Completa Superior , Femenino , Alimentos , Preferencias Alimentarias , Humanos , Masculino , Maxilar , Persona de Mediana Edad , Movimiento/fisiología
17.
J Prosthodont ; 28(1): e159-e171, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29785794

RESUMEN

This fourth and final part of a four-part series concerned with the development of nonanatomic denture occlusion follows nonanatomic tooth design from the time of Victor Sears' first nonanatomic tooth patent through the end of the 20th century. Part IV concentrates on nonanatomic teeth developed during the last five decades of the 20th century. Many of the designs featured in this series exhibited genius, while others are pure nonsense. Sears claimed that a new nonanatomic tooth design appeared every 9 months on average during the first 30 years of nonanatomic tooth production. Many current nonanatomic tooth patents are further refinements of those earlier designs.


Asunto(s)
Articuladores Dentales/historia , Diseño de Dentadura/historia , Dentadura Completa/historia , Diente Artificial/historia , Diente/anatomía & histología , Articuladores Dentales/tendencias , Oclusión Dental , Oclusión Dental Balanceada , Diseño de Dentadura/tendencias , Dentadura Completa/tendencias , Historia del Siglo XX , Humanos , Diente Artificial/tendencias , Estados Unidos
18.
J Prosthodont Res ; 63(1): 120-124, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30446410

RESUMEN

PURPOSE: To introduce a new and simple digital workflow to record dynamic occlusion, and apply it to occlusal analysis and prosthetic treatment in a virtual environment. METHODS: A table-top scanner (Identica hybrid) was used to transfer fabricated casts into a virtual environment. A facial scanner (Rexcan CS2) was used for facial scanning and target tracking. Four targets were attached to each of the four incisors in the maxilla and mandible to track jaw movement. Target position data were recorded in real time during eccentric movement. The targets were replaced with maxilla and mandible cast scan data, and mandibular movement relative to the maxilla was reconstructed. Four types of antagonist meshes were reconstructed in computer-aided design (CAD) software (EzScan8). The CAD software (Exocad) enabled checking of occlusal contacts in the maximal intercuspation position during eccentric movement. CONCLUSIONS: Target tracking data were transformed into video clips of dental cast scan data, which showed jaw movements in real time. Occlusal contact information was produced by the CAD software. Both dynamic and static occlusion analyses were performed with reconstructed eccentric movement antagonist meshes. Our new method for reconstructing eccentric movements of the mandible can reveal the occlusal dynamics of a patient within a virtual environment.


Asunto(s)
Articuladores Dentales , Oclusión Dental , Imagenología Tridimensional/métodos , Registro de la Relación Maxilomandibular/métodos , Mandíbula/fisiología , Movimiento , Diseño Asistido por Computadora , Modelos Dentales , Humanos , Prostodoncia , Realidad Virtual
19.
J Prosthodont ; 28(7): 833-836, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30298537

RESUMEN

In complete denture fabrication, the definitive maxillary cast is mounted on an articulator using a facebow transfer or mounting jig, and the mandibular cast is mounted using an interocclusal record. The technique presented describes an easy and inexpensive method for fabrication of a mounting jig and rigid cast supports for mounting complete dentures.


Asunto(s)
Diseño de Dentadura , Dentadura Completa , Articuladores Dentales , Registro de la Relación Maxilomandibular , Mandíbula , Maxilar
20.
J Prosthodont ; 28(1): e138-e147, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29508469

RESUMEN

Part III of this four-part series about nonanatomic denture tooth development traces the evolution of this movement from the mid-1930s through the World War II era up to the early 1950s. By this time, the general preference for posterior denture occlusion had shifted from anatomic to nonanatomic teeth, and all the major denture tooth manufacturing companies listed at least one nonanatomic design in their inventories.


Asunto(s)
Articuladores Dentales/historia , Diseño de Dentadura/historia , Diente Artificial/historia , Diente/anatomía & histología , Articuladores Dentales/tendencias , Oclusión Dental , Oclusión Dental Balanceada , Diseño de Dentadura/tendencias , Dentadura Completa/historia , Dentadura Completa/tendencias , Dentaduras/historia , Dentaduras/tendencias , Historia del Siglo XX , Humanos , Diente Artificial/tendencias , Estados Unidos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA