Digital analyses of Bolton tooth size ratios and their association to gender, angle class, and other occlusal traits: a study using a partially automated digital 3D model analysis.

BACKGROUND: This study aims to verify Bolton's values for tooth size ratios and to evaluate possible relationships to different occlusal traits using precise digital measurement methods. MATERIALS AND METHODS: Including 1000 consecutively selected patients from three study centres a digital, partially automated model analysis was performed utilizing the software OnyxCeph. The measurements comprised tooth width for calculation of anterior (AR) and overall ratio (OR) as a percentage, arch width, length, perimeter, overjet, overbite, space analysis in millimetre and the assessment of the angle classification. RESULTS: AR and OR were significantly increased compared to Bolton's ratios of 77.2% (AR) and 91.3% (OR). In the gender comparison, male patients showed larger tooth size ratios, especially in the OR. Patients with Angle Class II/1 and II/2 had smaller tooth size ratios than patients with Angle Class III and I. Thus, patients with Angle Class II/1 had the largest tooth diameters in all maxillary teeth and with Angle Class II/2 the smallest tooth sizes in the mandible. The largest tooth widths in the lower jaw were observed in the Angle Class III patient group. Furthermore, a negative correlation from AR/OR to overjet, overbite, and available space in lower jaw as well as a positive correlation to available space in upper jaw was detected. CONCLUSIONS: There is a clear correlation between the tooth size ratios and the present dysgnathia as well as other orthodontically relevant occlusal traits. This prior knowledge about our patients is extremely important to create an individualized treatment plan and enable sufficient occlusion. To achieve a functionally good occlusion with correct overjet and overbite, it is essential that the maxillary and mandibular teeth are proportional in size. Any deviation from the ideal patient in terms of tooth size, number, shape, or arch must be considered in the pre-therapeutic treatment plan in combination with the existing dysgnathia in order to be able to achieve a stable anterior and posterior occlusion with appropriate adjustments to the therapy post-therapeutically.

Dental damage: Creating 3D anatomical models to illustrate destructive effects on human teeth.

Forensic odontologists often must identify human remains with damaged teeth. This damage is due to high-impact accidents, violence, or disasters. This 2-part study aimed to create two 3D digital models. They should show the destructive effects of physical and chemical agents on human teeth and popular dental materials. Researchers created an e-survey to investigate how digital models are perceived as an educational tool for Forensic Odontology. Also, a systematic review assessed experimental studies on the effects of high temperature on various prosthodontic materials. According to the results of the survey, most participants (n=69; 79%) agreed that they would find a 3D model useful for training. Participants misidentify images of burned and broken teeth under Ellis and Davey system (1970). The systematic review identified dental implant and dental crown as the most studied prosthodontic materials exposed to heat. The researchers designed dental damage model 1 to represent restored and unrestored burnt teeth, postmortem pink teeth, and traumatic injuries. The dental damage model 2 was created to demonstrate the effects of various types of damage to different prosthetic and restorative dental materials, as well as the impact of acid, water, and burial on restorative materials as additional information. Both models were edited, sculpted and painted using 3D modelling software ZBrush (2020. 1.4) and Blender (version 3.6.2). The dental damage models were uploaded and labelled on Sketchfab (Cédric Pinson, Paris, France). The study's materials could transform the teaching of complex tooth changes.

Evaluating the long-term stability of a predefined palatal region for tooth movement analysis.

OBJECTIVES: We conducted a three-dimensional (3D) analysis of orthodontic tooth movement (TM) using digital dental models (DMs), focusing on the palatal region of interest (PROI), aiming to evaluate the long-term stability of the PROI, validate the 3D TM analysis with PROI registration, and compare it with conventional lateral cephalometric analyses. METHODS: Twenty adult patients treated with a multibracket appliance were evaluated at their first visit (T0) and at least 5 years later (T1) using DMs and lateral cephalograms (LCs). The long-term stability of PROI was assessed by calculating the point cloud distances between DM-T0 and DM-T1. TM analysis using DM with PROI registration for the maxillary central incisors was assessed through linear and angular measurements in the sagittal view and subsequently compared with the LCs. RESULTS: The average point cloud distance of the PROI between DM-T0 and DM-T1 was 0.21 mm (standard deviation, 0.13 mm). TM analysis using DMs demonstrated excellent reproducibility for both linear and angular measurements (intra-rater correlation coefficient, > 0.99). The 95 % limits of agreement between the DM and LC measurements were < 5.14° for angular change, 3.53 mm for horizontal displacement, and 0.98 mm for vertical displacement. No significant differences were observed in the angular and linear measurements when the TM was compared using the DMs and LCs. CONCLUSIONS: The PROI remained stable for over 5 years, supporting the reproducibility and accuracy of TM assessment using PROI registration in orthodontic clinical practice. CLINICAL SIGNIFICANCE: DM analysis lacks the risks associated with X-ray exposure and can be easily performed in daily clinical practice, indicating its potential for future clinical applications. These findings further support the use of DM with PROI registration for TM analysis in orthodontic clinical practice, emphasizing its long-term stability and reproducibility.

The influence of three different primary treatment protocols on 5-year-old maxillary growth in patients with complete unilateral cleft lip and palate.

The study evaluated the effects of three different primary treatment protocols on maxillary growth in patients aged 5 years with complete unilateral cleft lip and palate (UCLP). The secondary objective was to assess the influence of initial cleft severity, family history of class III, and status of permanent lateral incisor on maxillary growth. In total, 54 patients with non-syndromic complete UCLP were included and grouped as follows: group An underwent lip adhesion, cheilorhinoplasty associated with tibial periosteal graft for hard palate repair, and finally veloplasty; group B underwent lip adhesion, then cheilorhinoplasty with intravelar veloplasty, and finally a hard-palate repair; group C underwent cheilorhinoplasty with intravelar veloplasty and then a hard-palate repair. Five-year maxillary growth was assessed on dental models, both clinically and digitally. No difference was found with GOSLON-Yardstick scoring. Five-year measurements showed that group C tended to have the best maxillary arch morphology (p = 0.012). Initial cleft severity did not impact maxillary growth, but status of permanent lateral incisor and family history of class III did (p = 0.019 and p = 0.004, respectively). In patients aged 5 years, the two-stage approach appeared to be the least detrimental to growth development. Predictive factors for growth retardation included the absence of lateral incisor and a family history of class III.

Palatal Morphology After Treatment of Children With Obstructive Sleep Apnoea Using the Modified Twin-Block Appliance.

OBJECTIVE: To investigate changes in the upper maxillary palates of children with obstructive sleep apnoea (OSA) and mandibular retraction who were treated using modified twin-block appliances (MTBAs). METHODS: Thirty-five OSA children (age: 6-12 years) with mandibular retraction were included as the experimental group and 35 children who were Angle's class I but without mandibular retraction were included as the control group. The experimental group was treated with MTBA. Plaster models were made before the treatment and at the end of the 6-month treatment period. Plaster models of the control group were made at inclusion and after 6 months. Some plaster models were excluded because of damage or their failure to exhibit sufficiently clear marks, which left 26 pairs each for the experimental and control groups. The gender and age of the experimental group were matched with those of the control group at the end of the treatment. Three-dimensional (3D) digital model information was gathered using the external oral scanning model, and the data were extracted and analysed statistically to clarify the morphologic improvement in the maxillopalatine in OSA children treated using MTBAs. RESULTS: After the OSA children with mandibular retraction were treated with MTBAs, the maxillary intercusp width, intermolar width, anterior palate width, posterior palate width, and surface area and volume of the maxillary palate significantly increased (*P < .05). By contrast, the anterior palatal height-apex level (H3) significantly decreased (*P < .05). CONCLUSIONS: Compared with the control group, the narrow maxillary arch and basal bone were significantly enlarged after the OSA children with mandibular retraction were treated using MTBAs. The palatal surface area and volume increased, thereby allowing more space for accommodating the tongue and relieving transverse dissonance of the dentition.

Three-dimensional digital model-assisted minimally invasive needle penetration and steel plate internal fixation in treatment of Sanders types Ⅱ and Ⅲ calcaneal fractures / 中国组织工程研究

BACKGROUND:At present,open reduction and internal fixation and minimally invasive needle aspiration are commonly used in patients with Sanders types Ⅱ and Ⅲ calcaneal fractures.However,there is little comparison between the clinical efficacy of the two methods and high-level clinical evidence is still available. OBJECTIVE:To compare the curative effect of Sanders types Ⅱ and Ⅲ calcaneal fractures treated by three-dimensional digital model-assisted minimally invasive needle penetration and tarsal sinus incision and manual reduction and internal fixation with steel plate. METHODS:From January 2021 to October 2022,80 patients with Sanders types Ⅱ and Ⅲ calcaneal fractures who were treated in the Department of Orthopedics,Cangzhou Hospital of Integrated Traditional Chinese and Western Medicine in Hebei Province were randomly divided into control group(40 cases)and observation group(40 cases).The control group was treated with manual reduction and internal fixation with steel plate through the traditional tarsal sinus incision,while the observation group was treated with a three-dimensional digital model assisted with minimally invasive needle penetration fixation.The operation time,blood loss,hospitalization time and fracture healing time of the two groups were recorded.The changes in Maryland score,AO-FAS score,pain visual analog scale score,quality of life score(SF-36 score),and imaging parameters(B?hler angle,Gissane angle,calcaneal length,width and height)were observed before and 12 months after operation in the two groups.The complications during the follow-up were recorded. RESULTS AND CONCLUSION:(1)Operation time,blood loss,hospitalization time and fracture healing time in the observation group were lower than those in the control group(all P<0.05).(2)The Maryland score,AO-FAS score,SF-36 score,B?hler angle,Gissane angle,calcaneal length and height of the two groups after treatment were significantly higher than those before treatment(all P<0.05).Visual analog scale score and calcaneal width were significantly lower than those before treatment(all P<0.05).(3)After 12 months of follow-up,the incidence of complications in the observation group was lower than that in the control group(all P<0.05).(4)In conclusion,the treatment of Sanders types Ⅱ and Ⅲ calcaneal fractures with three-dimensional digital model-assisted minimally invasive needle penetration fixation can significantly improve the operation time,bleeding volume and other perioperative indicators,and can reduce the occurrence of multiple complications.The recovery of ankle function,relief of pain symptoms,and improvement of quality of life are equivalent to traditional therapy.

Older adults in the digital health era: insights on the digital health related knowledge, habits and attitudes of the 65 year and older population.

BACKGROUND: The COVID-19 pandemic has increased internet use by older age groups to an unprecedented level in Hungary mirroring the general tendency in the total population. Nevertheless, international trends indicate that this group is less likely to use digital health technologies than younger ones. The aging population raises the question of successfully integrating elderly people into the digital health ecosystem. Our research aim is to investigate the digital health usage patterns and attitudes of the population aged 65 and over through a representative sample. METHODS: A national representative questionnaire survey was conducted by telephone (CATI), interviewing 1723 respondents. Within this sample we examined 428 people in the over-65 age group, 246 in the 65-74 age group and 182 in the over-75 age group. Predictors of demand for digital solutions were tested using binary logistic regression model. RESULTS: 50.8% of people aged 65-74 and 37.1. % of people aged 75 + use the internet for health-related purposes, mostly to access websites. 85% of respondents in 65-74 and 74% in 75 + age group have used more than one digital health device and around 70% of both age groups have a need for more than one digital solution. 90.2% (64-75 age group) and 85.7% (75 + age group) of respondents are familiar with e-prescription, 86.4% and 81.4% of them use it. 77.1% of 65-74-year-olds have heard of and nearly half 45.5% have used online appointment. More than half (52.7%) of the respondents in this age group have heard of and used electronic transmission of medical records and data. A similar proportion has heard about and used apps: 54.3% has heard of them, but only 17.3% has used them. The multivariate analyses emphasized that the need for digital solutions increases with the level of education and the more benefits one perceives in using digital solutions. CONCLUSION: Our research has shown that the senior age group has measurable needs in the field of digital health, so helping them on this journey is in the interest of the whole health ecosystem. Their high level of interest is indicated by the fact that more than a fifth of older adults would like to have access to between 7 and 10 of the maximum number of digital devices available. The differences between the two age groups - with younger people being more open to digital solutions and using them more - and the fact that the under 65s are better adapted digitally in all respects, raises the possibility that the specific trends in digital health for older people may virtually disappear in 10 years' time (when the under 65s now enter this age group).

Digitalizing the TIM-1 Model using Computational Approaches-Part One: TIM-1 Data Explorer.

The TIM-1 gastrointestinal model is one of the most advanced in vitro systems currently available for biorelevant dissolution testing. This technology, the initial version of which was developed nearly 30 years ago and has been subject to a number of significant updates over this period, simulates the dynamic environment of the human gastrointestinal tract, including pH, transfer times, secretion of bile, enzymes, and electrolytes. In the pharmaceutical industry, the TIM-1 system is used to support drug product design and provide a biopredictive assessment of drug product performance. Typically, the bioaccessibility data sets generated by TIM-1 experiments are used to qualitatively compare formulation performance, and the use of bioaccessibility data as inputs for physiologically based pharmacokinetic (PBPK) modeling for quantitative predictions is limited. To expand the utility of the TIM-1 model beyond standard bioaccessibility measurements (which define the fraction available for absorption), we have developed a computational tool, TIM-1 Data Explorer, to describe the fluid and mass balance within the TIM-1 system. The use of this tool allows a detailed inspection and in-depth interpretation of the experimental data. In addition to mass balance calculation, this model also can be used to describe the critical processes a drug substance would undergo during a TIM-1 experiment, such as dissolution, precipitation on transfer from the stomach to duodenum, and redissolution. The TIM-1 Data Explorer was validated in two case studies. In the first case study with paracetamol, we have shown the ability of the simulator to adequately describe mass transfer events within the TIM-1 system, and in the second study with a weakly basic in-house compound, PF-07059013, the TIM-1 Data Explorer was successfully used to describe dissolution and precipitation processes.

A case report on digital preoperative design, clinical application and finite element analysis for a patient with ankylosing spondylitis kyphosis.

Objective: By assessing a case of ankylosing spondylitis (AS) after thoracic lumbar protrusion deformity in a digital model and verifying its effectiveness after surgery for orthopaedic surgery process simulation, a finite element model was established for biomechanical experiments. Method: A 56-year-old patient with AS underwent preoperative thoracic lumbar spine computed tomography. The data were reconstructed using MIMICS16.0 software and modelled to design and measure the nailing parameters. A three-dimensional model was established using ANSYS14.0 software, and the actual surgical procedure was simulated using biomechanical experiments. The model was verified by comparing the X-ray films obtained from patients during preoperative forward bending, stretching and lateral flexion, with the model further tested using the Hueter-Volkmann principle. Result: On comparing the measurements across three different load cases (forward bending, after stretching and lateral flexion) in patients with AS after thoracic lumbar protrusion deformity and the original X-ray images, no difference was found between the model of deformation and real patient movement displacement across the vertebral body. On simulating the stress distribution, the measured T10-L4 vertebral body stress values at every point in the injured vertebrae were, on the whole, directed at both the upper and lower ends and exhibited a decreasing trend, and the stress distribution gradually decreased from the injured vertebrae (T12 and L1) to the upper and lower ends. Conclusion: The accuracy of the research model is high, the geometric similarity is good and relevant applied anatomy can be undertaken using the model parameter measurement. This study provides a successful example of the application of digital technology in the field of spinal deformity and a novel idea for the treatment of AS-related kyphosis.

Deep Reinforcement Learning Environment Approach Based on Nanocatalyst XAS Diagnostics Graphic Formalization.

The most in-demand instrumental methods for new functional nanomaterial diagnostics employ synchrotron radiation, which is used to determine a material's electronic and local atomic structure. The high time and resource costs of researching at international synchrotron radiation centers and the problems involved in developing an optimal strategy and in planning the control of the experiments are acute. One possible approach to solving these problems involves the use of deep reinforcement learning agents. However, this approach requires the creation of a special environment that provides a reliable level of response to the agent's actions. As the physical experimental environment of nanocatalyst diagnostics is potentially a complex multiscale system, there are no unified comprehensive representations that formalize the structure and states as a single digital model. This study proposes an approach based on the decomposition of the experimental system into the original physically plausible nodes, with subsequent merging and optimization as a metagraphic representation with which to model the complex multiscale physicochemical environments. The advantage of this approach is the possibility to directly use the numerical model to predict the system states and to optimize the experimental conditions and parameters. Additionally, the obtained model can form the basic planning principles and allow for the optimization of the search for the optimal strategy with which to control the experiment when it is used as a training environment to provide different abstraction levels of system state reactions.

The impact of digital twins on the evolution of intelligent manufacturing and Industry 4.0.

As the adoption of Industry 4.0 advances and the manufacturing process becomes increasingly digital, the Digital Twin (DT) will prove invaluable for testing and simulating new parameters and design variants. DT solutions build a 3D digital replica of the physical object allowing the managers to develop better products, detect physical issues sooner, and predict outcomes more accurately. In the past few years, Digital Twins (DTs) dramatically reduced the cost of developing new manufacturing approaches, improved efficiency, reduced waste, and minimized batch-to-batch variability. This paper aims to highlight the evolution of DTs, review its enabling technologies, identify challenges and opportunities for implementing DT in Industry 4.0, and examine its range of applications in manufacturing, including smart logistics and supply chain management. The paper also highlights some real examples of the application of DT in manufacturing.

The precision of two alternative indirect workflows for digital model production: an illusion or a possibility?

OBJECTIVE: Despite the clear drive from both research and clinical dentistry toward digital transformation, there are limitations to implementing intra-oral scanning (IOS) into daily dental practice. This study aimed to compare the precision of digital models obtained from two alternative indirect workflows to direct IOS. MATERIAL AND METHODS: Two indirect digital workflows were evaluated in this study. In the IOS group (direct), IOS directly obtained digital impressions of participants' upper and lower dental arches, while in the Scan Impression (Scan Imp) group (indirect), a desktop scanner scanned silicone-based impressions of upper and lower whole arches that were taken with plastic trays. In the cone-beam computed tomography impression (CBCT Imp) group (indirect), a CBCT machine scanned the silicone-based impressions. Then, the precision of the entire arch and individual teeth for all digital impressions was virtually quantified. Following superimposition, differences between standard tessellation language (STL) files obtained from both-direct and indirect-methods were evaluated by color-mapping and measuring the surface distance between superimposed STL files. Furthermore, 18 linear measurements were taken from each digital model. ANOVA with repeated measures, Pearson coefficient, and intraclass correlation coefficient were used for intergroup comparisons. RESULTS: The digital models obtained from the two indirect workflows differed from the IOS in some dental and intra-arch measurements but were considered clinically acceptable. Ranked against IOS, CBCT Imp models had greater precision, followed by Scan Imp. CONCLUSION: Digital models obtained from two indirect, alternative workflows, desktop, and CBCT scanning of impression, have clinically acceptable accuracy and reliability of tooth size and intra-arch measurements, providing the use of proper methodologies. CLINICAL RELEVANCE: There are some limitations to implementing IOS in daily clinical practice. However, several alternative digital model production techniques might provide an affordable solution. Although they may insignificantly differ in accuracy, all can be applied clinically.

A novel method for monitoring the maxillary tooth movement during orthodontics in 3D space.

AIM: The present study aimed to develop a method for measuring 3D maxillary tooth movement during orthodontic treatment and to verify the accuracy of the method. MATERIALS AND METHODS: A 3D model analysis method was established to measure tooth movement by combining the effects of CBCT and intraoral scans. Transformation matrices were used to abstract the motion features of the teeth and translate them into translations and rotations. To test the validity and reliability of the method for clinical application, the inclination of the central incisor was measured using a 3D model analysis method and cephalometric analysis. Measurement error, correlation, and agreement between the two methods were analyzed using the Dahlberg formula, intraclass correlation coefficient, and Bland-Altman analysis, respectively. The performance of the 3D model analysis method was evaluated by monitoring the canine movement of a patient who underwent a premolar extraction. RESULTS: The measurement error was 0.58 degrees for the 3D model analysis and 2.02 degrees for the cephalometric analysis. There was no significant difference in the central incisor inclination measurements between the cephalometric and the 3D model analyses methods. A high correlation (0.974) and narrow limits of agreement (-3.55 degrees, 4.16 degrees) were obtained between the two methods. Minute movements and additional details of orthodontic tooth movements could be observed using the 3D model analysis method. CONCLUSION: The 3D model analysis method was reliable and reproducible for clinical application in monitoring the 3D maxillary tooth movement during orthodontic treatment. The trueness should be further evaluated. (Int J Comput Dent 2023;26(1): 49-0; doi: 10.3290/j.ijcd.b3818301).

Treatment of class II malocclusion with Invisalign®: A pilot study using digital model-integrated maxillofacial cone beam computed tomography.

Background/purpose: The treatment effects of Invisalign® are still obscure due to methodological limitations of previous studies. We introduced a method to comprehensively evaluate the dental and skeletal changes of Class II malocclusion treated non-extraction with Invisalign® and compare with the virtual simulation of ClinCheck® using digital models integrated into maxillofacial cone-beam computed tomography (CBCT). Materials and methods: The pretreatment (T1) and posttreatment (T2) scanned digital images of actual dentitions were integrated into maxillofacial CBCT images. To evaluate three-dimensional movement of maxillary teeth and change of mandible position, T1 and T2 digital model-integrated maxillofacial CBCT images were superimposed using voxel-based registrations of stable cranial base structures. To evaluate movement of mandibular teeth, model-integrated mandibular CBCT superimposition was registered on mandibular basal bone. To compare achieved and predicted tooth movements, the actual dental images and the virtual digital models created by ClinCheck® were registered on the T1 dentitions. Results: For simulated upper first molar (U6) distalization of more than 1 mm, treatment accuracy ranged from 31.1% to 40.1%, which was significantly less than virtual planning and previous reports. In unilateral Class II subjects, the amount of U6 distalization on the Class II side was not significantly different from contralateral side, indicating efficacy of sequential distalization was questionable. Those with favorable overjet correction showed evidence of condylar distraction. Conclusion: Digital model-integrated CBCT superimpositions reflected the actual treatment changes in comparison with the virtual simulation, and showed that ideal occlusion was not achieved in mild to moderate Class II adult patients treated non-extraction with Invisalign®.

Dental arch changes comparison between Expander with Differential Opening, Hyrax-type and Haas-type expanders: A prospective clinical study.

OBJECTIVE: Compare changes in arch form after RME achieved by Expander with Differential Opening (EDO), Hyrax-type and Haas-type expanders. MATERIALS AND METHODS: Dental models were obtained from 61 patients aged 7-11 years before expansion (T1) and 6 months after the active phase when the appliances were removed (T2). The groups were formed according to the expander used: EDO (n = 18, mean age: 9.46 ± 0.82 years), Hyrax-type (n = 22, mean age: 9.62 ± 1.57 years) and Haas-type (n = 21, mean age: 9.29 ± 1.05 years). The expander`s activation protocol consisted of 7 mm, except for EDO`s anterior screw, which was 9 mm. The measurements of upper and lower intercanine distance, inter-first permanent molar, arch perimeter and length, maxillary canine and first-permanent molar inclination, and palatal depth were performed using the OrthoAnalyzer 3D software. Intergroup comparisons of T1 and between changes (T2-T1) were performed using ANOVA followed by Tukey. RESULTS: In the upper intercanine distance EDO provided a greater increase than Haas-type. In the distance between upper fist permanent molars EDO showed higher values than Haas-type and Hyrax-type. In the lower intercanine distance and maxillary arch length, Haas-type promoted higher increase than EDO. CONCLUSIONS: The EDO promoted greater transverse changes in anterior region than Haas-type and greater transverse changes in posterior region of the maxilla than both conventional expanders. The appliance used for RME influences dental arch changes after treatment; therefore, it is recommended to individualize the choice of expander depending on the clinical necessity of each case.

Study on clinical efficacy of a 3D model based on crown-root integration in clear aligners / 口腔医学

Objective@#To evaluate the clinical effect of clear aligners in the anterior region in non-extraction cases by establishing a three-dimensional model of crown-root fusion to guide clinical application.@*Methods@#Eleven patients visiting the orthodontic department of Xuzhou Stomatological Hospital from December 2020 to December 2021 were collected, and the orthodontic plan was designed using Maestro 3D Dental Studio scheduling software to obtain the expected three-dimensional model of the patient's orthodontic treatment result. CBCT, intraoral scan, and 3D reconstruction software were used to create a postoperative model of the patient. The crown and root data were aligned in Geomagic Studio 2014, and differences in torque and axial inclination between the actual model after treatment and the predicted model of the anterior teeth before treatment were compared in 3-matic.@*Results@#The actual torque angles of the anterior teeth were all smaller than the predicted angles before treatment, with the highest realization rate of 77.55% for lateral incisors and the lowest of 60.70% for central incisors; the actual axial inclination angles of the anterior teeth were also smaller than the predicted angles before treatment, with the highest realization rate of 81.49% for central incisors and the lowest of 74.95% for cuspids. @*Conclusion@# A digital model of crown-root integration based on a combination of 3D reconstruction and intraoral scanning techniques is advantageous in assessing the efficacy of clear aligners. In non-extraction cases with clear aligner, the efficiency of movement is higher for small areas of the anterior region.

Endoluminal larynx anatomy model - towards facilitating deep learning and defining standards for medical images evaluation with artificial intelligence algorithms.

The pioneering nature of this work covers the answers to two questions: (1) Is an up-to-date anatomical model of the larynx needed for modern endoscopic diagnostics, and (2) can such a digital segmentation model be utilized for deep learning purposes. The idea presented in this article has never been proposed before, and this is a breakthrough in numerical approaches to aerodigestive videoendoscopy imaging. The approach described in this article assumes defining a process for data acquisition, integration, and segmentation (labeling), for the needs of a new branch of knowledge: digital medicine and digital diagnosis support expert systems. The first and crucial step of such a process is creating a digital model of the larynx, which has to be then validated utilizing multiple clinical, as well as technical metrics. The model will form the basis for further artificial intelligence (AI) requirements, and it may also contribute to the development of translational medicine.

Endodontic management of a fused left maxillary second molar and two paramolars using cone beam computed tomography: A case report.

BACKGROUND: Fused teeth usually involve several complications, such as the development of caries in the groove between fused crowns, tooth impaction, diastemas, aesthetic and periodontal problems, and pulpal pathosis, due to the complex anatomical structure of fused teeth. A thorough diagnosis is paramount to forming an accurate treatment plan and obtaining a favourable prognosis. With the advent of cone-beam computed tomography (CBCT), accurate 3-dimensional images of teeth and their surrounding dentoalveolar structures can now be readily obtained, and the technology can accurately provide a minimally invasive approach to acquire detailed diagnostic information. Therefore, we utilize CBCT data herein to generate a digital model for the infected region in a patient, and this model enables us to better plan the management of his case. CASE SUMMARY: This report details the diagnosis and endodontic treatment of a rare case involving a fused maxillary second molar and two paramolars with apical periodontitis. The patient experienced pain upon biting and cold sensitivity in the area of the maxillary left molar. No caries or other defects were identified in these teeth, and a normal response to a pulp electric viability test was observed. With the aid of CBCT and digital model technology, we initially suspected that the infection originated from the isthmus between the maxillary second molar and two paramolars. Therefore, we only treated the isthmus by an endodontic approach and did not destroy the original tooth structure; furthermore, the vital pulp was retained, and good treatment outcomes were observed at the 24-month follow-up. CONCLUSION: This finding may provide new insights and perspectives on the diagnosis and treatment of fused teeth.

Design, Modeling and Implementation of Digital Twins.

A Digital Twin (DT) is a set of computer-generated models that map a physical object into a virtual space. Both physical and virtual elements exchange information to monitor, simulate, predict, diagnose and control the state and behavior of the physical object within the virtual space. DTs supply a system with information and operating status, providing capabilities to create new business models. In this paper, we focus on the construction of DTs. More specifically, we focus on determining (methodologically) how to design, create and connect physical objects with their virtual counterpart. We explore the problem into several phases: from functional requirement selection and architecture planning to integration and verification of the final (digital) models. We address as well how physical components exchange real-time information with DTs, as well as experimental platforms to build DTs (including protocols and standards). We conclude with a discussion and open challenges.

Experience in utilizing a novel 3D digital model with CT and MRI fusion data in sarcoma evaluation and surgical planning.

OBJECTIVE: To assess sarcoma margins with more accuracy and aid surgical planning, we constructed three-dimensional (3D) digital models with computed tomography(CT) and magnetic resonance imaging (MRI) image fusion data and validated the preciseness of the models by comparing them with 3D models constructed with CT only data. MATERIALS AND METHODS: We retrospectively reviewed a consecutive set of patients treated in our center who were preoperatively evaluated with the fusion image model. Models based on fusion images or CT-only data were constructed. Volumes of both tumors were calculated and the tumors were overlapped to see the location of differences between the two models. RESULTS: A consecutive 12 cases (4 male vs. 8 female) were included in this study. Most of the tumors were located in the pelvic bone or spine. The volume of the two tumor models was different and the differences were mainly in the peripheral region of the tumor. CONCLUSION: CT and MRI fusion image 3D models are more accurate than models with CT-only data and can be very helpful in preoperative planning of sarcoma patients.