Appliance Design Research Articles

Preventing and management of mouth ulcers caused by orthodontic

Orthodontic-induced mouth ulcers are a common complication arising from mechanical irritation and increased plaque accumulation during treatment. These painful lesions significantly impact the comfort and compliance of patients undergoing orthodontic care. Various factors contribute to their development, including appliance design, oral hygiene, dietary habits, stress, and systemic conditions like nutritional deficiencies. Effective prevention and management strategies are essential to mitigate these effects and enhance patient outcomes. Prevention focuses on minimizing mechanical trauma through improved appliance designs such as rounded brackets and self-ligating systems, and the use of protective barriers like orthodontic wax and silicone strips. Maintaining optimal oral hygiene with adjunctive tools, antimicrobial rinses, and dietary adjustments plays a pivotal role in reducing plaque accumulation and preventing mucosal injuries. Behavioral interventions, including stress management and addressing parafunctional habits, further support ulcer prevention. Management approaches include the use of topical treatments like corticosteroid-based ointments and bio-adhesive gels to alleviate pain and promote healing. Low-level laser therapy (LLLT) accelerates tissue repair and provides analgesic effects, emerging as an effective adjunctive treatment. In more severe cases, systemic antibiotics or anti-inflammatory medications may be employed to control secondary infections and support immune responses. Patient education is critical in ensuring adherence to these strategies, emphasizing the importance of dietary modifications, stress control, and consistent oral care. Comprehensive care combining innovative technologies, evidence-based treatments, and personalized patient support addresses both the etiology and impact of orthodontic-induced ulcers. These integrated strategies not only reduce the incidence and severity of lesions but also improve overall patient satisfaction and treatment compliance. As advancements in materials and therapeutic modalities continue, the potential for enhanced outcomes in orthodontic care grows, ensuring better quality of life for patients during treatment.

Effect of occlusal appliances on the sleep of individuals with bruxism: A systematic review and meta-analyses

ABSTRACT Objective This systematic review determined whether occlusal appliance use influences the sleep of individuals with sleep bruxism. Material and Methods Six databases and the gray literature were searched to identify randomized and non-randomized clinical trials comparing slow wave sleep and sleep quality of sleep bruxers before and after occlusal appliance use. The Risk of Bias was assessed using Cochrane tools and Meta-analyses were performed to compare data. The Certainty of the evidence was evaluated by Grading of Recommendations Assessment, Development, and Evaluation approach. Results Two randomized and eight non-randomized studies were included. Meta-analyses indicated that soft and hard appliances influenced the slow-wave sleep and sleep quality of sleep bruxers, as determined by polysomnography (Z = 5.58; p < .001), the Pittsburgh Sleep Quality Index (Z = 3.45; p < .001), and the Sleep Assessment Questionnaire (Z = 48.1; p < .001). Conclusion Occlusal appliance use significantly impacts slow-wave sleep and sleep quality in sleep bruxism individuals, regardless of appliance design or material.

UPGRADED SCIENTIFIC ORHODONTIC SIMULATOR WITH TEMPERATURE CONTROL AND THERMOCHAMBER

Introduction There are many orthodontic simulators known as Typodonts used since 1981. We use in daily practice electrodonts by Savaria-Dent Kft (Szombatheley, Hungary), a laboratory device, which simulates the orthodontic movements. The electrodonts were created by setting the teethes in a silicone mould filled with dual consistency wax. Every tooth is wrapped in coper coil and continuous electric current is injected, heating the wax generating orthodontic movement under the action of orthodontic wires. This device comes with a time regulator and the amperage is limited to 2 Amps. The electrodont must be under direct supervision of the user because the heat inducted by copper in the wax will over melt the wax resulting complete destruction of the electrodont and subsequent failure in obtaining the results of the treatment performed on electrodont. Aim of the study Primary goal of this study was to evolve an orthodontic simulator for scientific and didactic use. The system developed in this study has the added benefit of tooth of time and visual movement quantification, increasing students understanding and allowing the study of biomechanical principles and appliance design in order to obtain the replication of the case for head to head studies of different orthodontic wires from ultra-flexible to thermo activated ones. Secondary goal was to reduce the human intervention for reconfiguration of electrodonts due to loss of wax or complete damage by overheating. Materials and methods. We initiated a collaboration between Orthodontic Department and the Dental Materials Department University of Medicine and Pharmacy Craiova for a tool necessary to evaluate orthodontic treatment with fixed appliance systems for scientific and didactic means. We aimed to reduce the time lost in laboratory to readjust the electrodonts during othodontic treatment stages, also to reduce student failure when operating the electrodonts. Results In the laboratory, we upgraded the electrodont using a thermo chamber independent of ambient interferences, we placed in direct contact with the wax for each dental arch thermometer that measures directly the temperature and disconnect the influx of current in the device when the wax is overheating 25 degrees is the maximal reference. The active phase of orthodontic treatment is situated between 20 and 25 degrees Celsius. We assessed the upgraded electrodonts with the new configuration and the results were evaluated by Orthodontic Specialist and dental technician, without any evidence of melting wax and the treatment was continuous. Conclusions The electrodont is an incredible tool for didactic and scientific purposes, offering consistent and accountable results of simulated orthodontic treatment. The upgraded version is offering this experience without the delay caused by repairing, correcting the wax model, with the help of technicians and the danger of completely melting the wax if it is not supervised correctly.

Management of Ankylosed Teeth with Fixed Space Regainer: Case Reports

Ankylosis, the abnormal fusion of root cementum and surrounding bone, commonly affects primary molars, leading to space loss and infraocclusion. This often results in mesial tipping of the adjacent permanent molar, necessitating orthodontic intervention to regain space, upright the molar, and establish proper occlusion. In mixed dentitions, patient compliance and proper appliance design are critical, as inappropriate appliances can cause root resorption and undesirable tooth movements. This case report presents a three-step treatment approach for managing ankylosis using a novel fixed appliance that uses the ankylosed tooth as skeletal anchorage. The process includes 1) space regaining, 2) extraction of the ankylosed tooth, and 3) space maintenance for the successor tooth’s eruption. The fixed appliance, comprising a minitube, double-helical spring, free arm, and resin ball, was used to regain space and facilitate the eruption of the permanent successor by correcting the inclination of the adjacent first permanent molar. Two patients with mixed dentitions were treated successfully, achieving space regaining and molar uprighting without anchorage loss. This three-step treatment is simple, effective, and produces desirable outcomes in a short time, making it a promising alternative for pediatric patients with ankylosis, space loss, and mesial inclination of adjacent teeth. The novel appliance emphasizes the importance of stable and biocompatible anchorage in pediatric dentistry.

Enhancing flow uniformity and reducing turbulent kinetic energy in refrigerator freezers through magnetic resonance velocimetry-based structural modifications

High energy efficiency and low operational noise are increasingly demanded in premium household appliances. Magnetic resonance velocimetry (MRV) has recently emerged as a versatile flow visualization technology, particularly suited for the efficient design of such appliances. This study conducted a comprehensive analysis of a 3/5 scale freezer model, incorporating the cooling system, compartment, and cabinets, all fabricated using stereolithography three-dimensional (3D) printing. By focusing on flow characteristics, 3D mean velocity and turbulent kinetic energy (TKE) fields were measured, identifying regions of non-uniform flow and elevated TKE. To address these issues, structural modifications were introduced in an improved model. These modifications included refining the central structure of the fan chamber, altering inlet geometries, and adding a fillet at the inlet edge. The results were significant: a more uniform flow distribution was achieved, with a 15 percentage-point increase in the effective flow rate through the evaporator's finned area, a reduction in secondary flow energy in the fan chamber, and a substantial decrease in TKE. Consequently, the improved model demonstrated enhanced energy efficiency and quieter operation. These findings highlight the potential of MRV as an effective tool for analyzing complex flow systems in appliance design.

Imagining the future household refrigerator: A study investigating the dimension of user needs

Household refrigerator concepts have evolved with changing applicational scenarios and requirements, providing users with support for healthy eating, personal care, and other activities in the kitchen and other areas of the home. However, current research on exploring user expectations and requirements for household refrigerators lacks considering the perspective of applicational scenarios and activity support. For this study, we invited 45 participants to explore immersive experience methods and conducted semi-structured interviews to investigate user requirements for future household refrigerators in different home areas and obtain dimensional details related to user needs, ultimately generating new insights into the demand for connected, intelligent, emotional, easy to use. Our findings are instructive for the design of future refrigerators in household scenarios and provide guidance and references for the design of other smart home appliances.

Digital Models and 3D Biomechanics Analysis in Orthodontics. Part 1: Vector Calculations

Biomechanics is essential for optimizing orthodontic appliances and controlling dental movement. Charles J. Burstone pioneered a three-dimensional (3D) approach in orthodontics, advocating for a shift beyond appliance-focused methods. Initially, biomechanics studies were constrained to two-dimensional (2D) analysis due to the complexities of 3D evaluation. Despite progress in computational tools and digital modeling, orthodontic biomechanics has largely maintained a 2D orientation. This paper advances orthodontic biomechanics into 3D, re-evaluating concepts previously limited to 2D frameworks. A dedicated software, DDP-Ortho (Ortolab, Poland), is introduced to enable orthodontists to analyze and resolve biomechanical challenges in 3D, facilitating appliance designs with precise 3D force systems. The representation and calculation of force vectors and moments in 3D are detailed, emphasizing the inherent complexity absent computational support. Key processes such as vector subtraction and addition, fundamental for assessing and refining orthodontic force systems, are explained. Additionally, the vector split (couple replacement) method, previously described in 2D, is extended to 3D, addressing the unique constraints and challenges of this approach. These tools promise to refine the accuracy and effectiveness of orthodontic treatments, setting the stage to examine the interactions between 3D force systems and dental movement, which will be addressed in a subsequent paper, to broaden the potential of contemporary orthodontic therapy.

3D printed indirect bonding trays: transfer accuracy of bar vs shell design in a prospective, randomized clinical trial.

To compare the transfer accuracy of two different indirect bonding (IDB) trays. Digital IDB was performed on a total of 30 patients using one of two designs: shell and bar trays, with 15 patients in each group. Trays were designed with the Appliance Designer software (3Shape A/S, Copenhagen, Denmark). Angular (torque, tip, angulation) and linear (mesiodistal, buccolingual, occlusogingival) differences were compared between the bonded intraoral scans taken immediately after IDB and the virtually bracketed model prepared in Ortho Analyzer software (3Shape A/S) using open source GOM inspect software (GOM GmbH, Braunschweig, Germany). There were no significant differences found between the bar and shell groups. Within the groups, significant tip differences were found between the incisors, canines, and premolars in both groups (P = .0001). Additionally, a statistically significant torque difference was found in the canines and incisors in the shell group. The percentage of values that deviated from the clinical acceptance limit was relatively higher in the bar group. Although there was no statistical difference between groups, the shell tray showed better results according to clinical acceptability limits. This study is important as it is the first clinical study to compare directly printed transfer trays with different designs.

Implications of Lingual Orthodontics Compared to Conventional Orthodontics.

In orthodontics, the treatment plan and the impact of orthodontic appliances on patients' aesthetic appearance have significantly influenced patients' aesthetic demands over time. Patients considering orthodontic treatment are very concerned about the potential compromise in facial appearance that conventional orthodontic treatment could cause. Lingual orthodontics offers an aesthetically pleasing appearance compared to conventional orthodontic systems, addressing the growing demand for inconspicuous treatment options. This review examines the implications of lingual orthodontics compared to conventional orthodontics, focusing on aesthetics, oral health outcomes, and patient satisfaction. The benefit of lingual brackets is that when positioned on the teeth's lingual surfaces, they are almost undetectable. However, they are associated with increased difficulty in oral hygiene maintenance due to their placement, leading to higher plaque accumulation that causes compromised periodontal health. Conversely, studies show a lower incidence of white spot lesions on lingual surfaces compared to buccal surfaces, suggesting a reduced risk of caries. Challenges with lingual systems include increased tongue discomfort and speech difficulties. Despite these challenges, lingual orthodontics demonstrates favourable outcomes for patients prioritising aesthetics. Future advancements should focus on improving appliance designs to enhance patient comfort and oral hygiene accessibility, ensuring optimal treatment outcomes. Interdisciplinary collaboration and comprehensive oral hygiene education are essential to maximise the benefits of lingual orthodontics.

Effect of Anchorage Modifications on the Efficacy of Miniscrew-Assisted Rapid Palatal Expansion: A Systematic Review and Meta-Analysis.

Mini-implant-assisted rapid palatal expansion (MARPE) offers a non-surgical alternative for expanding the basal bone, increasing skeletal effects while minimizing undesirable dental side effects. This systematic review and meta-analysis evaluatethe effectiveness of MARPE in terms of transverse skeletal development, dentoalveolar changes, and periodontal effects, with consideration of appliance design. A review was conducted across multiple databases, including PubMed, MEDLINE, Embase, Scopus, and Springer, covering studies published between 2005 and 2024. Randomized controlled trialsinvolving MARPE, with specific attention to design variations (e.g., miniscrew type, number, diameter, length, position, and activation protocol), were selected. Transverse skeletal expansion, assessed via changes in the nasal width, was reported in six of seven studies, with an average increase ranging from 0.31 mm to 2.90 mm for MARPE, compared to 0.11 mm to 2.46 mm for conventional Hyrax expanders. Maxillary width expansion ranged from 2.89 mm to 9.08 mm with MARPE and from 2.59 mm to 8.51 mm with Hyrax. Periodontal changes were reported in six studies, although details were generally unclear. The use of four self-drilling miniscrews with once-daily activation over an extended period produced greater nasal width expansion, greater average skeletal expansion of the maxilla, and less dental inclination and dentoalveolar expansion compared to Hyrax. No significant differences were observed between short and long miniscrews, although wider miniscrews resulted in improved outcomes. The MARPE technique, especially when using a design with four self-drilling miniscrews and daily activation until the targeted expansion is reached, offers notable benefits compared to the conventional Hyrax appliance. This method improves both nasal and maxillary skeletal expansion, lessens dental inclination, and reduces negative effects relative to traditional approaches.

Comparison of 1- and 3-piece directly 3-dimensional printed indirect bonding trays: An in vitro study

This study aimed to compare the transfer accuracy of indirect bonding trays of different thicknesses and numbers of pieces. Digital indirect bonding was performed on 56 printed resin models, divided into 4 groups with 14 models in each: 1-mm 1-piece tray (OPT), 2-mm OPT, 1-mm 3-piece tray (TPT), and 2-mm TPT. The trays were designed using Appliance Designer (3Shape A/S, Copenhagen, Denmark). Angular (torque, tip, or angulation) and linear (mesiodistal, buccolingual, occlusogingival, or vertical) differences were compared by using open-source GOM Inspect software (GOM GmbH, Braunschweig, Germany). In the buccolingual direction, the 1-mm TPT (0.180 ± 0.041 mm) was significantly more accurate than the 1-mm OPT (0.240 ± 0.032 mm). In the vertical direction, significant differences were seen between the 1-mm and 2-mm OPTs (1-mm OPT: 0.220 ± 0.043 mm; 2-mm OPT: 0.428 ± 0.143 mm; P= 0.003) and between the 1-mm and 2-mm TPTs (1-mm TPT: 0.210 ± 0.072 mm; 2-mm TPT: 0.340 ± 0.062 mm; P= 0.004) in the total region. In the tip angle, significant differences were seen between the 1-mm and 2-mm OPTs and between the 1-mm OPT and TPT. In the torque angle, a significant difference was seen between the 1-mm TPT (2.815°±0.350°)and 2-mmTPT (2.368° ± 0.245°; P= 0.017). Both the thickness and the splitting of the trays impacted the bracket bonding accuracy. The 1-mm trays were more accurate than the 2-mm trays. Despite a few statistically significant differences between the 1-mm OPT and TPT, the 1-mm OPT was recommended for clinical use, considering the designing and placing of the trays.

Digital planning in joint orthodontic-restorative care.

Combined orthodontic-restorative treatment represents an increasing proportion of our practice, mirroring increasing provision of adult orthodontics and refinements in appliance design. By harnessing simple digital technology, it may be possible to promote more predictable aesthetic, biological and functional interdisciplinary outcomes. In particular, digital approaches can be embedded in the diagnostic and treatment planning phase, enhancing our communication with patients and colleagues while also permitting more detailed analysis and more refined planning.

A visual digital twin framework based on residual-based fourier neural operator online simulation method

ABSTRACT To enjoy a wonderful cooking experience in a smart kitchen, users and designers need a visual interaction platform. This paper proposes a DT framework incorporating data processing, flow field online simulation, equipment monitoring, interaction and visualization. Specifically, the DT online simulation and visualization of the kitchen fume flow field serve as the foundation for appliance design and control. Additionally, users can gain deeper insight into the state and change trends of the kitchen. To address the online simulation of the flow field, a RFNO online simulation method is proposed. In addition, this paper proposes an Echarts-based 2D and UE5-based 3D flow field visualization method to enable dynamic visualization and interaction of the flow field. The proposed DT framework was successfully verified in the case of the smart kitchen, demonstrating its efficiency and effectiveness.

Comparative biomechanical analysis of four different tooth- and bone-borne frog appliances for molar distalization : Athree-dimensional finite element study.

The purpose of this study was to analyze the biomechanical effects of four different designs of frog appliances for molar distalization using finite element analysis. Athree-dimensional finite element model including complete dentition, periodontal ligament, palatine, and alveolar bone was established. Four types of frog appliances were designed to simulate maxillary molar distalization: tooth-button-borne (TypeA), bone-borne (TypeB), bone-button-borne (TypeC), and tooth-bone-borne (TypeD) frog appliances. Aforce of 10 N was applied simulating ascrew in the anteroposterior direction. To assess the von Mises stress distribution and the resultant displacements in the teeth and periodontal tissues, geometric nonlinear theory was utilized. Compared to the conventional tooth-borne frog appliance (TypeA), the bone-borne frog appliances showed increased first molar distalization with enhanced mesiolingual rotation and distal tipping, but the labial inclination and intrusion of the incisors were insignificant. When replacing the palatal acrylic button with miniscrews (TypesB andD), more anchorage forces were transmitted from the first premolar to palatine bone, which was further dispersed by the assistance of apalatal acrylic button (TypeC). Compared to tooth-borne frog appliances, the bone-borne variants demonstrated aclear advantage for enmasse molar distalization. The combined anchorage system utilizing palatal acrylic buttons and miniscrews (TypeC) offers the most efficient stress distribution, minimizing force concentration on the palatine bone.

Design and Application of an Electric Appliance for Measuring the Systolic and Diastolic Pressure

Design and Application of an Electric Appliance for Measuring the Systolic and Diastolic Pressure

A Novel Design of an Oral Appliance for Monitoring Electromyograms of the Genioglossus Muscle in Obstructive Sleep Apnea Syndrome.

Obstructive sleep apnea (OSA) is a prevalent source of sleep-disordered breathing. OSA is most commonly associated with dysfunctions in the genioglossus (GG) muscle. In this study, we present the first version of a medical device that produces an electromyogram (EMG) of the GG. The prototype is composed of a (custom-made) 3D-printed mouthpiece. Impressions were taken for the lower arch and scanned with a lab scanner to be converted into digital impressions. ExoCad software was used to design the appliance. Fusion 360 software was then used to modify the design and create tubes to house the electrodes in a bilateral configuration to secure excellent and continuous contact with the GG muscle. Silver-silver chloride electrodes were incorporated within the appliance through the created tubes to produce a muscle EMG. In this preliminary prototype, an EMG amplifier was placed outside the mouth, and isolated electric wires were connected to the amplifier input. To test the design, we ran experiments to acquire EMG signals from a group of OSA patients and a control group in wakefulness. The GG EMGs were acquired from the participants for 60 s in a resting state whereby they rested their tongues without performing any movement. Then, the subjects pushed their tongues against the fontal teeth with steady force while keeping the mouth closed (active state). Several features were extracted from the acquired EMGs, and statistical tests were applied to evaluate the significant differences in these features between the two groups. The results showed that the mean power and standard deviation were higher in the control group than in the OSA group (p < 0.01). Regarding the wavelength during the active state, the control group had a significantly longer wavelength than the OSA group (p < 0.01). Meanwhile, the mean frequency was higher in the OSA group (p < 0.01) at rest. These findings support research that showed that impairment in GG activity continues in the daytime and does not only occur during sleep. Future research should focus on developing the device to be more user-friendly and easily used at home during wakefulness and sleep.

Revolutionizing Smiles: Advancing Orthodontics Through Digital Innovation.

Orthodontics is undergoing a digital revolution, transforming traditional techniques with modern technology. This evolution is driven by the need for precise diagnosis and treatment planning. Digital platforms, including digital radiography andcone beam computed tomography (CBCT), are replacing conventional methods, enhancing documentation, analysis, and appliance production. Three-dimensional imaging enables customized treatment plans and appliance design using computer-aided design and computer-aided manufacture (CAD/CAM). Integration of digital models and software facilitates treatment simulation and patient communication. Digital videography enhances diagnostic capabilities. Embracing digital processes is essential for improved patient care and practice efficiency in orthodontics. This review article on digital orthodontics aims to provide a comprehensive overview and critical analysis of the current advancements, technologies, applications, benefits, and challenges in the field of orthodontics utilizing digital tools and technologies.

A digital CAD/CAM configurator for the production of orthodontic appliances – Going new ways

Functional therapy in growing patients is a highly relevant area in orthodontics. With the increasing integration of computer-aided design and manufacturing technology (CAD/CAM) in orthodontics, we are witnessing significant advancements in the design of orthodontic appliances. Modern 3D printing technologies allow for the creation of complex, customized equipment in a cost-effective and time-efficient manner, using robust and durable resins. Additionally, the creative input of dental CAD design programs has led to the development of new designs.The aim of this report is to present a novel digital orthodontic prescription that aligns with the concept of a “full digital workflow”. This prescription utilizes a digital virtual configurator, enabling effective communication between the clinician, the technician and the patient.Using this prescription system, clinicians can easily configurate an orthodontic appliance before sending it to a dental technician for individualisation. 3D printing of the final design can then be performed directly within the dental office or by the technician. This approach allows the clinician to explore different orthodontic equipment options and modules, without the requirement for a demanding and sophisticated design process and without any knowledge of CAD. The availability of the present configurator might represent a fundamental advancement in the field of the CAD/CAM production of removable appliance linked to economic and ecological benefits.

Understanding the e-cooking experience from the perspective of the everyday cook in Nakuru, Kenya

Transitioning to electric cooking in East Africa offers established health benefits and promising economic, time-saving, and environmental advantages for everyday cooks. Furthermore, battery-supported e-cooking systems can facilitate earlier adoption in regions with unreliable grid quality. However, successful adoption necessitates understanding of how the needs and behaviors of everyday cooks can be effectively translated into e-cooking practices. This nine-month study engaged 20 participants from Nakuru, Kenya, observing their transition to e-cooking with battery supported appliances. Qualitative methods were used to understand changes in cooking practices. The findings comprehensively analyze participants' preferences and concerns about traditional cooking and e-cooking and summarize the cooking experiences in journey maps. The study addresses the benefits, challenges, and unresolved issues of transitioning to e-cooking, including time savings, appropriateness of e-appliances, cost implications, and gender roles. The study raises questions about appliance design, fuel stacking and the co-benefits of biomass cooking. It highlights the importance of addressing safety concerns and providing training on electricity usage alongside e-cooking adoption. The economic benefits, particularly when systems include battery storage, remain uncertain due to potential appliance inefficiencies and behaviour changes that can impact energy consumption, undermining anticipated benefits. These findings inform avenues for comprehensive e-cooking services that support the transition to e-cooking.

Manufacturing of PEEK orthodontic baseplate and 3D-printed alloy components from an intraoral scan.

This paper demonstrates a digital manufacturing technique of a removable orthodontic appliance from an intraoral scan. An intraoral scan was made for the maxillary and mandibular arches. 3Shape Orthodontics Appliance Designer produced the virtual Hawley retainer, consisting of alloy components (Adam Clasps and Fitted Labial bow) and a base plate. The base plate design was modified to adapt to inserting the alloy components, which were combined using cold-cured acrylic. The finished Hawley retainer was assessed intraorally. The described technique emphasizes the design specifications of digitally designed and manufactured removable orthodontic appliances. A combination of additive and subtractive techniques was successfully employed to manufacture the alloy components and base plate. This novel method provides an alternative approach to manufacturing removable appliances with computer-aided design (CAD)/computer-aided manufacturing (CAM) technologies. The described process offers a precursor to digital manufacturing of other developed designs of dental appliances.