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1.
J Contemp Dent Pract ; 22(1): 47-50, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34028362

RESUMEN

BACKGROUND: Condylar guidance can be determined using the clinical and radiographic methods. The present study was conducted to determine condylar guidance using the protrusive interocclusal wax method, panoramic radiographs, and lateral cephalogram. AIMS: The aim of the study was to compare the correlation between sagittal condylar guidance with protrusive interocclusal method, panoramic radiographs, and lateral cephalogram. MATERIALS AND METHODS: The present study was conducted on 82 dentulous subjects (males 41, females 41). In all subjects, interocclusal registration values and condylar guidance values were measured using panoramic radiographs and lateral cephalograms. RESULTS: The mean ± SD protrusive interocclusal registration value on the left side was 34.01 ± 1.2 mm and 34.08 ± 1.4 mm on the right side. The panoramic radiographs showed 35.12 ± 1.6 mm on the left side and 35.16 ± 1.7 mm on the right side. The mean ± SD protrusive interocclusal registration values on the left side was 34.01 ± 1.2 mm on the left side and 34.08 ± 1.4 mm on the right side. Lateral cephalogram showed 34.35 ± 1.3 mm on the left side and 34.67 ± 1.6 mm on the right side. There was a significant difference between the methods (p < 0.05). CONCLUSION: Sagittal condylar guidance can be evaluated using protrusive interocclusal method. Along with it, other methods such as panoramic radiographs and lateral cephalogram may also be used for recording condylar guidance. CLINICAL SIGNIFICANCE: Lateral cephalogram and panoramic radiographs may be reliable in determining condylar guidance, which can be used in orthodontic treatment planning.


Asunto(s)
Articuladores Dentales , Cóndilo Mandibular , Femenino , Humanos , Registro de la Relación Maxilomandibular , Masculino , Cóndilo Mandibular/diagnóstico por imagen , Radiografía Panorámica
2.
J Prosthodont ; 30(S1): 64-66, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33783092

RESUMEN

PURPOSE: The purpose of this Critically Appraised Topic was to investigate the possible clinical relevance of recording the immediate mandibular lateral translation. MATERIALS AND METHODS: A literature search limited to Clinical trials, Randomized Controlled Trials, Systematic Reviews, Meta Analyses, and using the PICO headings revealed no citations. Using the key words dental, occlusion, immediate side shift, also received no citations. Expanding the search criteria to include Journal Articles revealed 17 citations. Using dental occlusion, Bennett movement, revealed 21 citations. RESULTS: The cited articles were reviewed for relevance and duplicates were eliminated. The resulting 10 English language in vivo studies pertinent to the question were included. Other articles were culled from the author's library and the reference list of the aforementioned articles. There is no evidence on the prevalence of IMLT in patients in need of occlusal rehabilitation. There is agreement that the recording of the IMLT is reference point and recording instrument dependent. There is agreement that IMLT is observable on some patients and is minimal in magnitude. There is no evidence of any adverse clinical events as a result of not including IMLT in a restorative occlusal scheme. CONCLUSIONS: It is justifiable to question the necessity of attempting both to record immediate mandibular lateral translation on the average patient and reproduce it on an articulator.


Asunto(s)
Articuladores Dentales , Mandíbula , Humanos , Movimiento
3.
Int J Prosthodont ; 34(1): 13-20, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33570515

RESUMEN

PURPOSE: To evaluate and compare the occlusal fit of zirconia crowns designed using a digital articulator method and the traditional method in a self-controlled clinical trial. MATERIALS AND METHODS: Two zirconia crowns each were prepared for 12 patients with a single posterior tooth defect using two different methods: a digital articulator method and the traditional method. In the traditional method, casts were scanned using a model scanner, and the relative positions of the maxillary and mandibular arches were determined by the intercuspal occlusion of the casts. In the digital articulator method, casts were mounted on a mechanical articulator and scanned, and the relative positions were determined by their respective positions in the articulator. Additional dynamic occlusal adjustments of the digital articulator crowns were performed. Both groups of zirconia crowns were milled in a five-axis milling machine. The time required for occlusal adjustments, the occlusal contacts, the occlusal contact distributions, the number of occlusal contacts, the relative occlusal forces, and patient satisfaction (visual analog scale score) were evaluated. Wilcoxon test, McNemar test, and paired t test were used to compare the parameters between the two methods. RESULTS: The occlusal adjustment times for the digital articulator and traditional method crowns were 327 ± 226 seconds and 395 ± 338 seconds, respectively (P > .05). There were no significant differences in occlusal contacts, occlusal contact distributions, number of occlusal contacts, relative occlusal forces, or VAS scores between the two methods (P > .05). CONCLUSION: A digital articulator method for single-crown restoration was applied successfully. Crowns fabricated using a digital articulator or the traditional method can achieve acceptable occlusal fit for single-crown restorations.


Asunto(s)
Articuladores Dentales , Diseño de Prótesis Dental , Diseño Asistido por Computadora , Coronas , Humanos , Circonio
4.
Comput Methods Programs Biomed ; 198: 105814, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33197740

RESUMEN

BACKGROUND AND OBJECTIVE: Magnetic resonance (MR) imaging is increasingly used in studies of speech as it enables non-invasive visualisation of the vocal tract and articulators, thus providing information about their shape, size, motion and position. Extraction of this information for quantitative analysis is achieved using segmentation. Methods have been developed to segment the vocal tract, however, none of these also fully segment any articulators. The objective of this work was to develop a method to fully segment multiple groups of articulators as well as the vocal tract in two-dimensional MR images of speech, thus overcoming the limitations of existing methods. METHODS: Five speech MR image sets (392 MR images in total), each of a different healthy adult volunteer, were used in this work. A fully convolutional network with an architecture similar to the original U-Net was developed to segment the following six regions in the image sets: the head, soft palate, jaw, tongue, vocal tract and tooth space. A five-fold cross-validation was performed to investigate the segmentation accuracy and generalisability of the network. The segmentation accuracy was assessed using standard overlap-based metrics (Dice coefficient and general Hausdorff distance) and a novel clinically relevant metric based on velopharyngeal closure. RESULTS: The segmentations created by the method had a median Dice coefficient of 0.92 and a median general Hausdorff distance of 5mm. The method segmented the head most accurately (median Dice coefficient of 0.99), and the soft palate and tooth space least accurately (median Dice coefficients of 0.92 and 0.93 respectively). The segmentations created by the method correctly showed 90% (27 out of 30) of the velopharyngeal closures in the MR image sets. CONCLUSIONS: An automatic method to fully segment multiple groups of articulators as well as the vocal tract in two-dimensional MR images of speech was successfully developed. The method is intended for use in clinical and non-clinical speech studies which involve quantitative analysis of the shape, size, motion and position of the vocal tract and articulators. In addition, a novel clinically relevant metric for assessing the accuracy of vocal tract and articulator segmentation methods was developed.


Asunto(s)
Aprendizaje Profundo , Articuladores Dentales , Adulto , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Habla
6.
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
7.
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
8.
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
9.
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
11.
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
12.
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
13.
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
14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(1): 76-82, 2020 Dec 21.
Artículo en Chino | MEDLINE | ID: mdl-33550339

RESUMEN

OBJECTIVE: To establish the workflow of determining the jaw position of repositioning splint with the aid of digital technique, and to evaluate the accuracy of this workflow and compare the accuracy of raising different vertical dimensions in vitro. METHODS: A volunteer was recruited. The data of full-arch scans, cone beam computed tomography (CBCT) image and ultrasonic jaw motion tracking of the volunteer were acquired. The full-arch scans were merged with the CBCT image, which were then matched to the jaw motion tracking reference system. The jaw position of repositioning splint was determined when the anterior teeth opening was 3 mm and the condyle was in centric relation of the fossa in the sagittal plane. A digital repositioning splint was designed in the software based on virtual articulator and fabricated with additive manufacturing technique. After the splint was tried in, another CBCT image was taken and a qualitative analysis was conducted to compare the position of condyle between these two CBCT images. In the in vitro study, standard dental plaster casts with resin ball markers attached to the base were mounted onto a fully adjustable articulator in the intercuspal position. The dental casts were scanned by an extraoral scanner to establish digital models. The ultrasonic jaw motion tracking device was used to obtain simulated jaw movements on the articulator, which was repeated for three times. The digital models and data of jaw movements were merged in one coordination with the aid of bite forks. The jaw position of repositioning splint was determined by adjusting data of jaw movements, each of which was used to determine three vertical jaw positions 4 mm, 5 mm, and 6 mm with the horizontal jaw position of protrusion 2 mm. The virtual articulators with differently adjusted jaw movements were applied in designing repositioning splints, and the final repositioning splints and virtual jaw relationships were exported in STL format. Then the repositioning splints were fabricated with additive manufacturing technique and tried in plaster casts on the mechanical articulator, which were scanned and the jaw relationships on the mechanical articulator were exported later. The virtual jaw relationships and scanned jaw relationships were registered according to lower models and displacement of upper models was calculated. Ball markers were fit to acquire the coordinates of centers and absolute difference values of centers along three coordinating axes X, Y, and Z were calculated. One-way analysis of variance was conducted using SPSS 18.0 software to compare deviations of the three different vertical jaw relationships in two-side test and the significance level was 0.05. RESULTS: With the aid of multi-source data fusion and individualized jaw motion, the clinical workflow of determining jaw position of repositioning splint was preliminarily established. The designed jaw position was realized on the right and the condyle was more inferior than the designed position on the left. Both displacement of the upper models and absolute difference values of centers showed no significant differences (P>0.05) in different vertical jaw dimensions. The displacement of the upper models was (0.25±0.04) mm. The absolute difference values of centers along the three coordinating axes X, Y, and Z were respectively (0.08±0.01) mm, (0.30±0.02) mm, and (0.21±0.04) mm. CONCLUSION: A novel method of determining the jaw position of repositioning splint with the aid of digital technique is established. It is proved to be feasible by try-in after multi-data fusion, computer-aided design and computer-aided manufacturing. As is shown in vitro, it is accurate to apply this method in adjusting jaw position. Further clinical trial will be designed to evaluate its clinical effect.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Férulas (Fijadores) , Diseño Asistido por Computadora , Articuladores Dentales , Humanos , Registro de la Relación Maxilomandibular , Ferulas Oclusales , Programas Informáticos
15.
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
16.
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
17.
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
18.
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
20.
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
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