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1.
Bone Joint J ; 102-B(3): 365-370, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32114820

RESUMEN

AIMS: Patient-specific instrumentation has been shown to increase a surgeon's precision and accuracy in placing the glenoid component in shoulder arthroplasty. There is, however, little available information about the use of patient-specific planning (PSP) tools for this operation. It is not known how these tools alter the decision-making patterns of shoulder surgeons. The aim of this study was to investigate whether PSP, when compared with the use of plain radiographs or select static CT images, influences the understanding of glenoid pathology and surgical planning. METHODS: A case-based survey presented surgeons with a patient's history, physical examination, and, sequentially, radiographs, select static CT images, and PSP with a 3D imaging program. For each imaging modality, the surgeons were asked to identify the Walch classification of the glenoid and to propose the surgical treatment. The participating surgeons were grouped according to the annual volume of shoulder arthroplasties that they undertook, and responses were compared with the recommendations of two experts. RESULTS: A total of 59 surgeons completed the survey. For all surgeons, the use of the PSP significantly increased agreement with the experts in glenoid classification (x2 = 8.54; p = 0.014) and surgical planning (x2 = 37.91; p < 0.001). The additional information provided by the PSP also showed a significantly higher impact on surgical decision-making for surgeons who undertake fewer than ten shoulder arthroplasties annually (p = 0.017). CONCLUSIONS: The information provided by PSP has the greatest impact on the surgical decision-making of low volume surgeons (those who perform fewer than ten shoulder arthroplasties annually), and PSP brings all surgeons in to closer agreement with the recommendations of experts for glenoid classification and surgical planning. Cite this article: Bone Joint J 2020;102-B(3):365-370.


Asunto(s)
Artroplastía de Reemplazo de Hombro/métodos , Toma de Decisiones , Imagen Tridimensional , Osteoartritis/cirugía , Articulación del Hombro/cirugía , Cirugía Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/diagnóstico , Articulación del Hombro/diagnóstico por imagen
2.
Am J Orthod Dentofacial Orthop ; 157(3): 348-356, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32115113

RESUMEN

INTRODUCTION: The purpose of this study was to investigate the registration accuracy between intraoral-scanned crowns and cone-beam computed tomography (CBCT)-scanned crowns in various registration methods. METHODS: The samples consisted of 18 Korean adult patients, whose pretreatment intraoral scans and CBCT images were available. A 3-dimensional (3D) dental model was fabricated using a TRIOS intraoral scanner (3Shape, Copenhagen, Denmark) and the OrthoAnalyzer program (version 1.7.1.4; 3Shape). After the CBCT image was taken, 3D volume rendering was performed to fabricate a 3D dental model using InVivo5 software (version 5.1; Anatomage, San Jose, Calif). Registration of the 3D dental crowns made from intraoral- and CBCT-scanned images was performed with Rapidform 2006 software (Inus Technology, Seoul, Korea) by a single operator. According to registration methods, 3 groups were established: individual-arch-total-registration group, individual-arch-segment-registration group, and bimaxillary-arch-centric-occlusion-registration group (n = 18 per group). After the amounts of shell/shell deviation were obtained, the mixed model analysis of variance and Bonferroni correction were performed. RESULTS: Although there was no significant difference in the registration accuracy between the individual-arch-total-registration group and individual-arch-segment-registration group, the bimaxillary-arch-centric-occlusion-registration group exhibited the lowest registration accuracy (maxillary and mandibular teeth, all 0.21 mm in the individual-arch-total-registration group; all 0.20 mm in the individual-arch-segment-registration group vs 0.26 mm and 0.25 mm in the bimaxillary-arch-centric-occlusion-registration group; P <0.001). Color-coded visualization charts exhibited that most red spots were localized on the occlusal surface of the posterior teeth in all 3 groups. CONCLUSIONS: When considering the registration accuracy and convenience of the process, the individual-arch-total-registration method can be regarded as an efficient tool when integrating CBCT-scanned crown and intraoral-scanned crown.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Modelos Dentales , Adulto , Coronas , Humanos , Procesamiento de Imagen Asistida por Computador , Imagen Tridimensional , República de Corea
5.
Dent Clin North Am ; 64(2): 365-378, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32111275

RESUMEN

The use of 3-dimensional (3D) cone-beam computed tomography (CBCT) imaging in the dental office has become a common imaging modality. The authors present an overview of multiple treatments that would benefit from the use of this technology. From preoperative, intraoperative, to postoperative patient management, 3D technology plays a vital role in the dental practice. With the incorporation of 3D CBCT, intraoral scanners, and 3D printing, a dental provider can accurately plan and execute the treatment with greater confidence. The contemporary dentist, however, has many options for incorporating the digital workflow based on the specific practice needs.


Asunto(s)
Consultorios Odontológicos , Imagen Tridimensional , Tomografía Computarizada de Haz Cónico , Humanos , Impresión Tridimensional
6.
J Dent Educ ; 84(3): 301-307, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32176341

RESUMEN

Historically, predoctoral and advanced dental education programs used two-dimensional panoramic and periapical radiographs for implant planning. Three-dimensional (3D) Cone Beam Computed Tomography (CBCT) imaging has improved visualization of anatomic structures that can positively influence implant planning and surgical implant placement. The aim of this study was to assess how U.S. postdoctoral periodontics programs have incorporated CBCT technology into their curricula. A ten-question survey was sent to all 57 U.S. postdoctoral periodontics programs in November-December 2018. Thirty-seven responses were received, for a 65% response rate. All participating programs reported providing residents access to CBCT machines, and most of their residents received some training in the acquisition and interpretation of CBCT images. Nearly all (95%) participating programs provided training to apply implant planning software. Among the participating programs, 14% reported using a surgical guide fabricated with a CBCT scan 76-100% of the time, and 60% reported obtaining a CBCT scan for implant cases 76-100% of the time. These results suggest that, while residents are receiving training in CBCT and implant planning, it is not used often. There may be merit in adopting the American Academy of Oral and Maxillofacial Radiology's recommendation to use 3D imaging for all implant planning, with CBCT as the imaging modality of choice.


Asunto(s)
Implantes Dentales , Tomografía Computarizada de Haz Cónico Espiral , Tomografía Computarizada de Haz Cónico , Educación en Odontología , Humanos , Imagen Tridimensional , Periodoncia , Encuestas y Cuestionarios
7.
Int J Comput Dent ; 23(1): 49-56, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32207461

RESUMEN

AIM: Evaluation of appropriate models for computer-aided design/computer-aided manufacturing (CAD/CAM) in vitro studies by investigation of different model materials regarding suitability for intraoral scanners and dimensional stability. MATERIALS AND METHODS: A typodont model was prepared to accommodate a 10-unit prosthesis. The model was duplicated using six different materials: class IV die stone (DS), cobalt-chrome molybdenum (CoCrMo), epoxy resin (EPOX), polyurethane (PU), titanium (TI), and zirconia (ZI). An intraoral scanner was used to obtain three scans of each model. Reference datasets were generated using micro-computed tomography (micro-CT). The first scan was compared with the corresponding reference micro-CT dataset to assess its trueness. The precision was measured by comparing all scans within one test group. For the evaluation of dimensional stability, micro-CT was used to generate three-dimensional (3D) datasets of the models at different time intervals over a 6-week period. The models were kept under constant conditions during the study. All datasets were analyzed with software that determined the deviation of two datasets by alignment using a best-fit algorithm. RESULTS: The criterion of trueness was fulfilled by CoCrMo, EPOX, PU, and the typodont model. Scans of CoCrMo and ZI showed the best precision. PU and the typodont model did not meet the requirement of dimensional stability, whereas EPOX and gypsum were stable only for a period of 10 days. CONCLUSION: The CoCrMo model was the only one that met all the criteria for an appropriate model for CAD/CAM in vitro studies. The other investigated materials either lacked dimensional stability or could not be scanned accurately and reproducibly.


Asunto(s)
Diseño Asistido por Computador , Adaptación Marginal Dental , Aleaciones de Cromo , Técnica de Impresión Dental , Modelos Dentales , Humanos , Imagen Tridimensional , Titanio , Microtomografía por Rayos X
8.
Chem Pharm Bull (Tokyo) ; 68(2): 179-180, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32009086

RESUMEN

The purpose of this study was to clarify applicability of three-dimensional X-ray micro-computed tomography (3D X-ray micro-CT) to elucidate interior morphology of spherical adsorptive carbon fine granules. Scanning of small single spherical granule hold on the rotating sample stage provided the structural information without particular preparation (e.g., slicing) that can affect the definite morphology. The three model formulations with similar appearance showed different internal structure in the 3D images, including large hollow in one of them. Other formulations showed some small empty or higher density area in the filled granules, suggesting uneven distribution of carbon. The results indicated relevance of the X-ray micro-CT analysis on the physical characterization of the spherical adsorptive carbon granule formulations.


Asunto(s)
Carbono/química , Adsorción , Composición de Medicamentos , Imagen Tridimensional , Tamaño de la Partícula , Microtomografía por Rayos X
9.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(2): 73-79, 2020 Feb 09.
Artículo en Chino | MEDLINE | ID: mdl-32074666

RESUMEN

Objective: To establish a quantitative three-dimensional method based on intraoral scan to evaluate the changes of soft tissue, and to evaluate the changes of supracrestal gingival thickness (SGT) in skeletal class Ⅲ patients induced by periodontal regenerative and corticotomy surgery (PRCS). Methods: Twenty-two systematically and periodontally healthy skeletal class Ⅲ patients (4 males and 18 females, aged between 19 and 35 years), who were in need of combined orthodontic-orthognathic treatment and referred to the Department of Periodontology from the Department of Orthodontics and the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from January, 2018 to March, 2019, were collected in the study. The teeth involved were 112 anterior teeth (46 maxillary anterior teeth and 66 mandibular anterior teeth). PRCS in anterior tooth area was conducted before orthodontic decompensation. Probing depth (PD), bleeding index (BI) and keratinized gingiva width (KGW) were recorded before surgery and 6 months post-surgery. The intraoral digital impressions of maxillary and mandibular anterior teeth were obtained by 3-shape intraoral scanner before surgery and 6 months after surgery. The Standard Tessellation Language (STL) files were processed using Geomagic qualify 12.2 software to establish the soft tissue morphological measurement model, and to quantitatively analyze the changes of gingival thickness situated 1 to 2 mm apical to the free gingival margin on the median sagittal measurement plane. Results: Probing depth and bleeding index had no significant difference before and 6 months after operation (P>0.05). KGW in 6-month post-operation group [(5.18±2.32) mm] was significantly higher than that in pre-operation group [(4.22±1.43) mm] (P<0.05). Supracrestal gingival thickness situated 1 to 2 mm apical to the free gingival margin also significantly increased 6 months after surgery (P<0.05). The changes of gingival thickness situated 1 to 2 mm apical to the free gingival margin in the upper anterior area were (0.68±0.56) and (1.00±0.69) mm, respectively. The changes in the lower anterior area were (0.38±0.42) and (0.58±0.45) mm, respectively. The gingival changes of the upper anterior teeth were also significantly higher than those of the lower anterior teeth (P<0.01). Conclusions: The described quantitative measurement based on intraoral scan could be an effective method for quantitative evaluation of the changes of soft tissue. PRCS could safely increase the supracrestal gingival thickness as well as KGW in skeletal class Ⅲ patients who were in need of combined orthodontic-orthognathic treatment.


Asunto(s)
Encía/diagnóstico por imagen , Maloclusión de Angle Clase III , Procedimientos Quirúrgicos Orales , Adulto , Femenino , Humanos , Imagen Tridimensional , Masculino , Maxilar , Adulto Joven
10.
J Prosthodont ; 29(3): 269-271, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32065435

RESUMEN

In order to provide restorations and dental prostheses that are esthetically pleasing, functional and in harmony with a patient's occlusion, practitioners must have a thorough knowledge of dental anatomy. Recent studies have shown that virtual three-dimensional (3D) models greatly enhance educational outcomes in dental anatomy courses. This article describes a novel educational technique and uses videos and web-based portals to demonstrate how to create a virtual 3D tooth model from a scan of a natural tooth for use in dental anatomy courses.


Asunto(s)
Modelos Dentales , Prótesis Dental , Oclusión Dental , Humanos , Imagen Tridimensional , Estudiantes
11.
Instr Course Lect ; 69: 583-594, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32017753

RESUMEN

The glenoid is considered a weak link in total shoulder arthroplasty because failure on the glenoid side is one of the most common reasons for revision of total shoulder arthroplasty. Glenoid wear is commonly seen in glenohumeral arthritis and compromises glenoid bone stock and also alters the native version and inclination of the glenoid. It is critical to recognize glenoid wear and correct it intraoperatively to avoid component malposition, which can negatively affect the survivorship of the glenoid implant. The end point of correction for the glenoid wear in shoulder arthroplasty is controversial, but anatomic glenoid component positioning is likely to improve long-term survivorship of the total shoulder arthroplasty. Preoperative three-dimensional (3-D) computer planning software, based on CT, is commercially available. It allows the surgeon to plan implant type (anatomic versus reverse), size, and position on the glenoid, and also allows for templating deformity correction using bone graft and/or augments. Guidance technology in the form of computer-assisted surgery (CAS) and patient-specific instrumentation (PSI) allows the surgeon to execute the preoperative plan during surgery with a greater degree of accuracy and precision and has shown superiority to standard instrumentation. However, the proposed benefits of this technology including improved glenoid survivorship, reduced revision arthroplasty rate and cost-effectiveness have not yet been demonstrated clinically. In this review, we present the current evidence regarding PSI and CAS in managing glenoid deformity in total shoulder arthroplasty.


Asunto(s)
Artroplastía de Reemplazo de Hombro , Cavidad Glenoidea , Articulación del Hombro , Cirugía Asistida por Computador , Artroplastia , Humanos , Imagen Tridimensional
12.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(1): 95-100, 2020 Feb 01.
Artículo en Chino | MEDLINE | ID: mdl-32037774

RESUMEN

Dental implants have become the main choice for patients to fill in their missing teeth. A precise placement is the basis for a functional and aesthetic restoration. A digital surgical guide is a carrier that transfers the preoperative plan of dental implants to the actual surgery. This paper provides some references that can help clinicians improve the accuracy of implant surgery by stating the development, classification, advantages and disadvantages, and factors that affect the accuracy of digital guides.


Asunto(s)
Implantes Dentales , Cirugía Asistida por Computador , Diseño Asistido por Computador , Implantación Dental Endoósea , Estética Dental , Humanos , Imagen Tridimensional , Planificación de Atención al Paciente
13.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(1): 108-113, 2020 Feb 01.
Artículo en Chino | MEDLINE | ID: mdl-32037777

RESUMEN

Identifying the ideal implantation site is important for the long-term stability and effectiveness of follow-up restorations. Implant surgical guide and navigation are used to determine the implantation site in clinic and improve the precision of implantation. However, due to difficulties in digital methods, such as multiple procedures, high cost, and actual accuracy of more than 1 mm, many physicians still prefer to operate with free hand. In preoperative, intraoperative, and postoperative procedures, time-saving and practical methods for implant site evaluation are lacking. In many cases, oral physicians found that the position deviates only by cone beam CT, which was costly to modify the position. In this article, we presented a precise implantation insertion technology that is guided by a measurable technique throughout the implantation application for all implant systems. This method was guided by a dynamic control measuring ruler, which functions together with the measuring and intraoperative locating rulers. The 3D space of the operative area was measured by a measuring ruler prior to operation, and the implant plan and quantitative guidance design were conducted according to the measured and cone beam CT data. The whole implantation process was guided by the dynamic control measuring ruler, and measuring verification results were also considered. This method can realize the quantification of the entire preoperative space analysis, intraoperative precise implantation guidance, and postoperative site measurement and evaluation. This practical technique also helps to adjust the position, improve the implantation accuracy and is suitable in generalizing dental implantation.


Asunto(s)
Implantes Dentales , Cirugía Asistida por Computador , Diseño Asistido por Computador , Tomografía Computarizada de Haz Cónico , Implantación Dental Endoósea , Imagen Tridimensional , Planificación de Atención al Paciente
14.
Einstein (Sao Paulo) ; 18: eMD5223, 2020.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-32049130

RESUMEN

Computed tomography with multiple detectors and the advancement of processors improved rendered images and three-dimensional reconstructions in clinical practice. Traditional axial slices form non-intuitive images because they are seen in only one plane. The three-dimensional reconstructions can show structures details and diseases with complex anatomy in different perspectives. Cinematic rendering is a newly three-dimensional reconstruction technique, already approved for clinical use, which can produce realistic images from traditional computed tomography data. The algorithm used is based on light trajectory methods and the global lighting model, which simulate thousands of images from all possible directions. Thus, the technique shapes the physical propagation of light and generates a realistic three-dimensional image with depth, shadows and more anatomic details. It is a multidimensional rendering acquired through complex lighting effects. The aim of this article was to show the advance of three-dimensional technology with the cinematic rendering in images exams of the thoracic wall.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Imagen Tridimensional/métodos , Sarcoma Sinovial/diagnóstico por imagen , Neoplasias Torácicas/diagnóstico por imagen , Pared Torácica/diagnóstico por imagen , Adulto , Algoritmos , Humanos , Masculino , Persona de Mediana Edad , Sarcoma Sinovial/secundario , Tomografía Computarizada por Rayos X/métodos
15.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(2): 162-167, 2020 Feb 15.
Artículo en Chino | MEDLINE | ID: mdl-32030945

RESUMEN

Objective: CT three-dimensional reconstruction technology was used to simulate the placement of the lumbar cortical bone trajectory (CBT), to determine the starting point and direction of the screw trajectory. Methods: Between February 2017 and April 2018, 24 patients with lumbar CT were selected as the study object. There were 7 males and 17 females, with an average age of 50.4 years (range, 37-68 years). The CT DICOM data of patients were imported into Mimics 16.0 software, and the three-dimensional model of lumbar spine was established. A 5 mm diameter cylinder was set up to simulate the CBT by using Mimics 16.0 software. According to the different implant schemes, the study was divided into groups A, B, and C, the track of the screw respectively passed through the upper edge, the medial edge, and the lower edge of the isthmus of the pedicle. The intersection of simulated screw and lumbar spine was marked as region of interest (ROI) and a mask was generated. The average CT value [Hounsfield unit (HU)] and the screw length of ROI were automatically measured by Mimics 16.0 software. In addition, the head inclination angle and head camber angle of the screw were measured respectively. Point F was the intersection of the level of the lowest edge of the transverse process and the lumbar isthmus periphery. The horizontal and vertical distance between point F and the starting point were measured, and the relationship between the three schemes and the position of the zygapophysial joint and spinous process was observed. Results: Plan A has the highest ROI average HU, with the maximum value appearing in L 4; plan B has the longest screw length, with the maximum value appearing in L 5; plan C has the largest nail track head inclination angle, with the maximum value appearing in L 4; plan B has the largest nail track head camber angle, with the maximum value appearing in L 3. The screw length and head camber angle of the nail in group B were significantly greater than those in groups A and C ( P<0.05); the head inclination angle in groups A, B, and C was gradually increased, showing significant differences ( P<0.05); there was no significant difference in the average HU value of ROI between the 3 groups ( P>0.05). In plan A, 74.48% (143/192) screws had a horizontal distance of -2 to 4 mm from point F, a vertical distance of 6-14 mm from point F, a head inclination angle of (14.64±2.77)°, and a head camber angle of (6.55±2.09)°, respectively; in plan B, 84.58% (203/240) screws had a horizontal distance of 1-6 mm from point F, a vertical distance of 1-5 mm from point F, a head inclination angle of (26.93±2.21)°, and a head camber angle of (10.29±2.46)°, respectively; in plan C, 85.94% (165/192) screws had a horizontal distance of -2 to 3 mm from point F, a vertical distance of -2 to 4 mm from point F, a head inclination angle of (33.50±3.69)°, and a head camber angle of (6.47±2.48)°, respectively. Conclusion: Plan B should be selected as the starting point of the L 1-L 5 CBT implant. It is located at the intersection of the lowest horizontal line of the transverse process root and the lateral edge of the lumbar isthmus, which is 1-6 mm horizontally inward, 1-5 mm vertically upward, with a head inclination angle of (26.93±2.21)°, and a head camber angle of (10.29±2.46)°, respectively.


Asunto(s)
Hueso Cortical , Adulto , Anciano , Tornillos Óseos , Hueso Cortical/diagnóstico por imagen , Femenino , Humanos , Imagen Tridimensional , Vértebras Lumbares , Región Lumbosacra , Masculino , Persona de Mediana Edad , Tornillos Pediculares , Fusión Vertebral
16.
Radiol Clin North Am ; 58(2): 305-327, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32044009

RESUMEN

Reporting MR imaging of pelvic floor dysfunction can be made easy if radiologists understand the aim of each MR sequence and what to report in each set of MR images. For an MR imaging report that is critical in decision making for patient management, it is of paramount importance to the radiologist to know what to look for and where to look for it. This article presents a new term, integrated MR analytical approach. A reporting template is included in which all MR findings are presented in a schematic form that can be easily interpreted by clinicians from different subspecialties.


Asunto(s)
Imagen Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Trastornos del Suelo Pélvico/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/tendencias , Diafragma Pélvico/diagnóstico por imagen , Diafragma Pélvico/fisiopatología , Trastornos del Suelo Pélvico/fisiopatología
17.
Medicine (Baltimore) ; 99(5): e18983, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32000432

RESUMEN

INTRODUCTION: Basilar invagination (BI) is a common deformity in the occipitocervical region. The traditional surgical method of BI is direct transoral decompression followed by posterior decompression and fixation. Posterior-only decompression and fixation have achieved good efficacy in the treatment of BI in recent years, but complications are common due to the operation in the upper cervical vertebra and the medulla oblongata region. Moreover, posterior-only occipitocervical fusion combined with an intraoperative 3-dimensional (3D) navigation system is relatively rare, and reports of this procedure combined with 3D printing technology have not been published. We present a case of BI treated with posterior-only occipitocervical fusion combined with 3D printing technology and 3D navigation system to reduce the risk of surgical complications. PATIENT CONCERNS: A 55-year-old patient with a history of neck pain and numbness of the extremities for 6 years developed a walking disorder for 1 year. DIAGNOSES: Atlantoaxial dislocation with BI. INTERVENTIONS: The patient underwent posterior-only occipitocervical fusion combined with intraoperative 3D navigation system and 3D printing technology. OUTCOMES: The patient's walking disorder was resolved and he was able to walk approximately 100 m by himself when he was allowed to get up and move around with the help of a neck brace. At 6 months postoperatively, the patient reported that the numbness of the limbs was reduced, and he could walk >500 m by himself. CONCLUSION: Occipitocervical fusion is one of the established techniques for the treatment of BI. The biggest advantage of the 2 technologies was that it ensured precise implant placement. The advantages of intraoperative 3D navigation systems are as follows: real-time intraoperative monitoring of the angle and depth of implant placement; the best nailing point can be determined at the time of implantation, rather than according to the operator's previous experience; and the extent of screw insertion is visible to the naked eye, rather than being dependent on the "hand feel" of the surgeon. At the same time, the 3D printing technology can be applied to clarify the relationship between blood vessels and bone around the implant to minimize injury to important structures during implantation.


Asunto(s)
Articulación Atlantoaxoidea/cirugía , Imagen Tridimensional , Luxaciones Articulares/cirugía , Impresión Tridimensional , Fusión Vertebral/métodos , Vértebras Cervicales/cirugía , Descompresión Quirúrgica/métodos , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Hueso Occipital/cirugía , Tomografía Computarizada por Rayos X
18.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(1): 129-137, 2020 Feb 18.
Artículo en Chino | MEDLINE | ID: mdl-32071476

RESUMEN

OBJECTIVE: To provide a reference for using intraoral scanners for making clinical diagnostic dentures of edentulous jaws by comparing the accuracy of three intraoral scanners for primary impression and jaw relation record of edentulous jaws. METHODS: This study contained 6 primary impressions of the edentulous patients. Each of the impressions consisted of the maxillary primary impression, the mandibular primary impression and the jaw relation record. For each of them, a dental cast scanner (Dentscan Y500) was used to obtain stereolithography (STL) data as reference scan, and then three intraoral scanners including i500, Trios 3 and CEREC Primescan were used for three times to obtain STL data as experiment groups. In Geomagic Studio 2013 software, trueness was obtained by comparing experiment groups with the reference scan, and the precision was obtained from intragroup comparisons. Registered maxillary data of the intraoral scan with reference scan, the morphological error of jaw relation record was obtained by comparing jaw relation record of the intraoral scan with the reference scan. Registered mandibular data with jaw relation record of intraoral scan and the displacement of the jaw position were evaluated. Independent samples t test and Mann-Whitney U test in the SPSS 20.0 statistical software were used to statistically analyze the trueness, precision and morphological error of jaw relation record of three intraoral scanners. The Bland-Altman diagram was used to evaluate the consistency of the jaw relationship measured by the three intraoral scanners. RESULTS: The trueness of i500, Trios 3 and CEREC Primescan scanners was (182.34±101.21) µm, (145.21±71.73) µm, and (78.34±34.79) µm for maxilla; (106.42±21.63) µm, and 95.08 (63.08) µm, (78.45±42.77) µm for mandible. There was no significant difference in trueness of the three scanners when scanning the maxilla and mandible(P>0.05). The precision of the three scanners was 147.65 (156.30) µm, (147.54±83.33) µm, and 40.30 (32.80) µm for maxilla; (90.96±30.77) µm, (53.73±23.56) µm, and 37.60 (93.93) µm for mandible. The precision of CEREC Primescan scanner was significantly better than that of the other two scanners for maxilla (P<0.05). Trios 3 and CEREC Primescan scanners were significantly better than i500 scanner for mandible (P<0.05). The precision of the i500 and Trios 3 scanners for mandible was superior to maxilla (P<0.05). The upper limit of 95% confidence intervals of trueness and precision of three scanners for both maxilla and mandible were within ±300 µm which was clinically accepted. The morphological error of jaw relation record of the three scanners was (337.68±128.54) µm, (342.89±195.41) µm, and (168.62±88.35) µm. The 95% confidence intervals of i500 and Trios 3 scanners were over 300 µm. CEREC Primescan scanner was significantly superior to i500 scanner(P<0.05).The displacement of the jaw position of the three scanners was (0.83±0.56) mm, (0.80±0.45) mm, and (0.91±0.75) mm for vertical dimension; (0.79±0.58) mm, (0.62±0.18) mm, and (0.53±0.53) mm for anterior and posterior directions; (0.95±0.59) mm, (0.69±0.45) mm, and (0.60±0.22) mm for left and right directions. The displacement of the jaw position of the three scanners in vertical dimension, anterior and posterior directions and the left and right directions were within the 95% consistency limit. CONCLUSION: Three intraoral scanners showed good trueness and precision. The i500 and Trios 3 scanners had more errors in jaw relation record, but they were used as primary jaw relation record. It is suggested that three intraoral scanners can be used for obtaining digital data to make diagnostic dentures and individual trays, reducing possible deforming or crack when sending impressions from clinic to laboratory.


Asunto(s)
Técnica de Impresión Dental , Arcada Edéntula , Diseño Asistido por Computador , Modelos Dentales , Humanos , Imagen Tridimensional
19.
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 , Imagen Tridimensional , Registro de la Relación Maxilomandibular , Programas Informáticos
20.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(1): 144-151, 2020 Feb 18.
Artículo en Chino | MEDLINE | ID: mdl-32071478

RESUMEN

OBJECTIVE: To analyze the distribution and area of occlusal contacts of clinical dental model using three kinds of digital analysis methods, to compare the results of these methods and traditional occlusal analysis method, and to further analyze the characteristics of each digital analysis method. METHODS: A set of plaster models of normal subjects was selected. The models were scanned by lab scanner 3shape E4 and the files were exported in a stereolithography file format. In 3D analysis software Geomagic Studio 2013 and Geomagic Qualify 2013, the corresponding results of 3D occlusal contact distribution and occlusal contact area were obtained through three digital analysis methods: "3D color difference map method", "point cloud analysis method", and "virtual articulating paper method". The occlusal contact distribution and occlusal contact area were also obtained by two traditional occlusal analysis methods: "silicone interocclusal recording material method" and "scanned articulating paper mark method". A threshold of 100 µm was used to analyze the occlusal contacts and 100 µm was also the thickness of articulating paper used in this study. The results of these five different occlusal analysis methods were evaluated qualitatively and quantitatively. RESULTS: The results of 3D occlusal contact distribution obtained by the above five methods were basically consistent. The total occlusal contact area obtained by 3D color difference map method, point cloud analysis method, virtual articulating paper method, silicone interocclusal recording material method and scanned articulating paper mark method were 133.10 mm², 142.08 mm², 128.95 mm², 163.31 mm², and 100.55 mm² respectively. There was little difference between the results of three digital analysis methods. The results of occlusal contact area obtained by the digital methods and the traditional methods were different. CONCLUSION: The three digital analysis methods can provide reliable and accurate analysis results of occlusal contact distribution and occlusal contact area of dental model. The results obtained by these methods can serve as references for the digital occlusal surface design of dental prosthesis and clinical occlusal analysis.


Asunto(s)
Modelos Dentales , Programas Informáticos , Imagen Tridimensional
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