Hologram Usage in Orthodontics as A Study Model: A Comprehensive Review

Abstract

Orthodontics, a specialized field of dentistry focused on correcting malocclusions and dental irregularities, has evolved significantly in recent years. Traditional study models, such as plaster casts and digital impressions, have been the cornerstone of treatment planning and evaluation. However, the advent of holographic technology has introduced a novel and promising approach for orthodontic study models. This comprehensive review explores the utilization of holograms in orthodontics, highlighting their potential advantages, applications, and challenges.

Introduction

I. INTRODUCTION

Orthodontics is a specialized branch of dentistry dedicated to diagnosing and correcting malocclusions, dental irregularities, and other conditions that affect the alignment and aesthetics of the dentofacial complex. Effective orthodontic treatment planning and evaluation have traditionally relied on the use of study models, including plaster casts and digital impressions, to replicate a patient's dental arches and occlusion. These models serve as valuable tools for assessing the current state of a patient's dentition and developing treatment strategies. However, recent advancements in technology have brought about a paradigm shift in the field of orthodontics. Holography, a cutting-edge imaging technique that captures and reconstructs three-dimensional (3D) images of objects, presents an exciting opportunity to revolutionize the way orthodontists approach study models. Holography offers the ability to create dynamic, interactive 3D representations of the dental structures, providing a more comprehensive and accurate assessment of a patient's oral health1. This comprehensive review aims to delve into the integration of holography into the field of orthodontics. We will explore the underlying principles of holography, the equipment required for its application, and the myriad ways in which holograms are transforming orthodontic practice. From diagnostic applications and treatment planning to patient education and research, holography holds the promise of enhancing various facets of orthodontic care.

II. HOLOGRAPHIC TECHNOLOGY

Holographic technology is a cutting-edge imaging and display technique that captures and reproduces three-dimensional (3D) images of objects with stunning realism and depth. Unlike traditional two-dimensional imaging methods, holography records both the intensity and phase of light, allowing for the creation of holograms that provide a more comprehensive and immersive representation of the subject. Holography relies on the principle of wave front recording, which means that it captures the entire light field from an object, including the amplitude and phase information. This detailed information enables the reconstruction of a 3D image that appears as if it were a physical object. Holography typically requires a coherent light source, such as a laser, to create interference patterns between the reference beam and the object beam. This interference pattern is recorded on a photosensitive medium.2

Holograms are created by exposing a photosensitive medium, often a holographic plate or photosensitive film, to the interference pattern formed by the interaction of the object and reference beams. The medium stores the encoded 3D information.  To view a hologram, coherent light (usually from the same type of laser used during recording) is directed onto the holographic medium. The light interacts with the recorded interference pattern, reconstructing the 3D image in space. This reconstructed image can be viewed from various angles, allowing for a more comprehensive understanding of the subject.2,3

III. HOLOGRAPHIC EQUIPMENT

Holographic equipment used in orthodontics encompasses both hardware and software components. These components work in tandem to create and visualize holograms of a patient's dentition, offering orthodontists valuable diagnostic and treatment planning tools. A coherent light source, typically a laser, is a fundamental component of holographic equipment.

Lasers emit a narrow, focused beam of light with a single wavelength, ensuring the required coherence for hologram creation. Diode lasers and helium-neon (HeNe) lasers are commonly used in dental holography. A beam splitter is used to divide the laser beam into two parts: the reference beam and the object beam. The reference beam travels directly to the recording medium, while the object beam is directed toward the patient's dentition. Various optical components, including lenses and mirrors, are used to manipulate and focus the laser beams. Optics help control the size, position, and orientation of the holographic recording. The holographic recording medium, often a holographic plate or photosensitive film, is where the interference pattern created by the object and reference beams is captured. This medium can record the phase and amplitude of light, enabling the storage of 3D information. The holographic setup in orthodontics typically involves positioning the photosensitive medium, patient's dentition, and laser beams precisely. This setup ensures that the interference pattern is accurately recorded. Specialized software is used for both recording and reconstructing holograms. During recording, the software controls the laser, captures the interference pattern, and stores it as digital data. In the reconstruction phase, the software processes this data to recreate the 3D holographic image. Advanced software tools enable the manipulation and visualization of holograms. To visualize holograms, orthodontists require a holographic display. This can be in the form of a physical display that projects the 3D image into space or a computer monitor capable of displaying holographic reconstructions. Calibration devices are used to ensure the accuracy and alignment of the holographic setup. They help in fine-tuning the system to capture and reproduce high-quality holographic images. Proper patient positioning is crucial to maintain stability during hologram capture.2

IV. REVIEW OF LITERATURE

A pilot study by N. Harradine assessed the viability of holograms as substitutes for traditional plaster study casts in orthodontic clinical treatment. The study involved four clinicians' evaluations of 56 patients and found that holograms were perceived as informative and convenient by most clinicians. Holography showed promise as an alternative to study casts, but individual clinician preferences and further refinements may influence its adoption.4 A study by Sameh Talaat study investigated the validity and reliability of palatal superimposition of holograms of 3D digital dental models using the Microsoft HoloLens device compared to conventional computer-based superimposition. It found high repeatability, acceptable measurement error, and minimal absolute error, supporting the reliability of holographic superimposition. Holographic superimposition, facilitated by the HoloLens, offers a reliable means for assessing orthodontic treatment outcomes with high accuracy. Evaluation of Holographic Technology as a Substitute for Traditional Study Models in Orthodontics was done by Alejandro Romeo. That research assesses the validity and reliability of using holograms as substitutes for traditional study models in orthodontics. The study involved pre- and post-treatment digital maxillary dental models of 20 orthodontic cases treated by rapid maxillary expansion.5,6 It found that holograms allowed for virtual assessment of orthodontic treatment outcomes, with high repeatability and minimal measurement error. Holographic technology holds promise as an alternative to traditional study models, offering convenience, informativeness, and cost-effectiveness. Collectively, these studies highlight the growing interest and potential of holographic technology in the field of orthodontics. Holograms offer advantages such as enhanced visualization, interactivity, and precision, making them valuable tools for orthodontic diagnosis, treatment planning, patient education, and research. However, further research and refinement are needed to optimize the use of holography in clinical orthodontic practice and to address individual preferences and technical considerations.

V. APPLICATIONS OF HOLOGRAMS IN ORTHODONTICS

Holograms offer a range of applications in orthodontics, revolutionizing the field by providing orthodontists with advanced tools for diagnosis, treatment planning, patient education, research, and documentation. Holographic technology enables orthodontists to create highly accurate 3D models of a patient's dentition. These holographic study models provide a more comprehensive representation of the teeth and surrounding structures, facilitating precise diagnosis of malocclusions, tooth irregularities, and other dental conditions. Holograms offer orthodontists the ability to simulate treatment outcomes in 3D. Orthodontic practitioners can plan and visualize tooth movements, appliance placement, and treatment progress more effectively. This aids in developing customized treatment plans that optimize results and reduce treatment duration. Holographic models engage patients in a more immersive and interactive learning experience. Orthodontists can use holograms to educate patients about their specific orthodontic conditions, treatment options, and expected outcomes.7 This visual approach enhances patient understanding and helps them make informed decisions. Orthodontists can use holograms to demonstrate treatment processes to patients in real-time. This allows patients to see how their teeth will move and change throughout the treatment, fostering a deeper appreciation of the orthodontic process. Holographic technology can aid orthodontic researchers in studying tooth movement, treatment techniques, and the biomechanics of the dentofacial complex.

Holographic models provide a valuable platform for conducting experiments and simulations in a controlled virtual environment. Holograms can serve as a digital record of a patient's treatment progress. By capturing holographic images at various stages of treatment, orthodontists can create a longitudinal record of changes in the patient's dentition, offering valuable insights for research and documentation.8 Holographic models can be easily shared with other dental specialists and healthcare professionals involved in a patient's care. This facilitates interdisciplinary collaboration and improves communication among the healthcare team. The visual and interactive nature of holograms can motivate patients to adhere to their treatment plans. Seeing the progress and expected outcomes in 3D can encourage patients to actively participate in their orthodontic journey. Holograms can assist in the customization and fabrication of orthodontic appliances, such as braces or aligners. Precise 3D models can be used to create appliances tailored to an individual patient's unique dental anatomy. Holograms enable orthodontists to assess treatment outcomes accurately.9 By comparing holographic models before and after treatment, orthodontists can ensure that treatment goals have been achieved and make necessary adjustments if required.

VI. CHALLENGES

Implementing holographic technology may require training and technical expertise, which can be a barrier for orthodontists who are not familiar with holography. Acquiring and maintaining holographic equipment, such as HoloLens devices or holographic displays, can be expensive. This cost may limit the adoption of holographic technology in some orthodontic practices. The standardization of holographic techniques and measurements in orthodontics is an ongoing challenge. Ensuring consistency and accuracy across different systems and software is crucial. Integrating holography seamlessly into the orthodontic workflow can be challenging. Clinicians must adapt their practices to incorporate holographic technology effectively. While many patients may find holograms engaging, some may have reservations or discomfort with this technology. Clinicians need to consider patient preferences and comfort levels. The quality and capabilities of holographic hardware, such as HoloLens devices, may vary, impacting the overall experience and usability. As holographic technology involves digital data, ensuring data security and compliance with privacy regulations is crucial to protect patient information.10

Conclusion

In conclusion, the integration of holographic technology in orthodontics represents a significant advancement with the potential to revolutionize various aspects of the field. Despite these challenges, the studies reviewed in this report demonstrate that holographic technology has the potential to enhance orthodontic diagnosis, treatment planning, patient education, and research. As technology continues to advance and becomes more accessible, orthodontists and researchers have an opportunity to refine and optimize holography for orthodontic practice. In the coming years, ongoing research and development efforts are likely to further improve holographic systems, making them more user-friendly, cost-effective, and integrated into orthodontic workflows. As holography becomes more mainstream, it may play a significant role in shaping the future of orthodontics, offering innovative solutions that benefit both clinicians and patients.

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Copyright

Copyright © 2023 Gifty Winlet D , Domini C, Dr. Saravanan, Dr. Raj Vikram, Dr. Vivekanandhan. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.