Background

The American College of Radiology and the National Electrical Manufacturers Association created the Digital Imaging and Communications in Medicine (DICOM) worldwide standard in 1985 to assure that medical imaging systems are standardized, compatible and efficient. It defines a protocol for storing, transmitting and exchanging medical imaging data between devices, platforms and organizations. DICOM has grown vital in radiology, dentistry and other healthcare areas that rely on imaging. DICOM is the foundation for digital imaging processes in dentistry and allows data to be acquired, managed and exchanged between dental imaging equipment and software.

Dentistry has changed during the last 2 decades as a result of digital technology. Traditional film-based radiography has been replaced by digital imaging systems as it provides a higher picture quality, lower radiation exposure, shorter acquisition times and easy storage and sharing possibilities. This can increase the diagnosis accuracy and simplified healthcare operations. Intraoral radiographs, panoramic radiographs (orthopantomograms), cone beam computed tomography (CBCT), cephalometric imaging and intraoral scanners are all examples of digital imaging modalities. DICOM ensures standardization by offering a consistent file format and communication protocol that enables interoperability between systems. These imaging techniques are used to diagnose dental cavities, periodontal bone loss, periapical disease and evaluate craniofacial growth and treatment effects.

A DICOM file consists of 2 main components: pixel data which contains the actual image content and metadata. It provides detailed information about the image, patient and acquisition parameters. This combination ensures that DICOM files are self-contained and provide all the necessary information for interpreting and processing the image. This structured approach helps integrate imaging data into Picture Archiving and Communication Systems (PACS) and Electronic Health Records (EHRs).

DICOM is an important technique in dentistry to facilitate the interoperability between imaging equipment and software systems. Dental clinics frequently use a variety of technology like CBCT scanners, intraoral X-ray devices and digital impression systems which produced by different suppliers. Without a defined protocol like DICOM downloading and viewing pictures across different systems would be difficult and resulting in inefficiencies and probable data loss. DICOM is a worldwide standard that enables smooth communication between imaging devices, workstations and applications. A CBCT scan may be produced as a DICOM file and images from intraoral radiographs, panoramic X-rays and cephalometric investigations can be merged in a PACS to enable thorough treatment planning. This connectivity improves patient outcomes by correct diagnoses and efficient communication among dental professionals.

DICOM in dentistry has various advantages like better radiation exposure management especially in CBCT imaging. DICOM enables for the documenting of exposure parameters and allowing practitioners to optimize protocols and follow the ALARA principle. It also decreases the need for further scans by delivering precise diagnostic data. DICOM deployment confronts several problems lie cost, data storage, learning curve and data security. Transitioning to DICOM compatible systems may need a substantial investment in hardware, software and training. Dental practitioners may need training to efficiently use DICOM based systems and workflows.

Terminology of DICOM:

Association: A connection created between 2DICOM applications that allows DICOM data to be shared. It is possible to support many affiliations at the same time.

Attributes: They are things that represent anything about the information objects are described by attributes in DICOM.

Composite objects: DICOM objects can represent many or portions of several entities in “entity-relationship” (E-R) paradigm.

Data elements: An explanation of the descriptive properties or contents of the sets of data that according to the E-R paradigm, “provide a summary of entities.”

Data set: According to the E-R model this is the official definition of entities like patients, tools, pictures and their relationships from a perspective of the information organization.

Unique identifier: It is a number construct which is used to reference an entity. It has a unique name which helps the targeted entity to be found and retrieved and identifying it from other entities.

Value representation (VR): In DICOM, it describes how the value of an attribute is represented like text, patient name or binary data.

Library: It is used phrases to describe patient information like name, ID number and date of birth.

Indications

Implant Dentistry:

DICOM based Cone Beam Computed Tomography (CBCT) is essential for implant design and placement because it provides precise 3D images of bone density, ridge architecture and surrounding structures. Integrating DICOM information into CAD/CAM systems allows physicians to build surgical guides and prosthetic components with great precision.

Orthodontics:

Cephalometric pictures, CBCT scans and intraoral scans are used in orthodontic treatment planning all of which adhere to the DICOM standard for accuracy. CBCT data offers a 3D image of the craniofacial area which aids in the diagnosis of skeletal anomalies and dental alignment problems. DICOM compatible software combines CBCT data with digital impressions.

Endodontics:

CBCT imaging and stored and shared in DICOM format is increasingly used in endodontics to address complex root canal systems. It helps identify root canal morphology, peripheral pathology, resorption defects and fractures and providing better visualization than traditional 2D radiographs for diagnosis and treatment planning.

Oral and Maxillofacial Surgery:

DICOM based CBCT imaging is crucial for procedures like impacted third molar extractions, orthognathic surgery and maxillofacial trauma management. It aids in locating impacted teeth, assessing fractures or cysts and preoperative planning for reconstructive surgery. DICOM facilitates virtual surgical simulations and 3D printing.

Prosthodontics and Restorative Dentistry:

Digital impressions from intraoral scanners are used to design crowns, bridges and dentures and ensuring high precision and fit. Integration with CBCT data reduces treatment time and eliminates inaccuracies.

Periodontics:

CBCT scans give detailed visualization of periodontal bone levels and aiding in diagnosis and treatment of periodontal diseases. DICOM images accurately assess bone loss, furcation involvement and defects.

Pathology and Trauma:

DICOM based imaging is crucial for diagnosing oral pathologies like cysts, tumors and foreign bodies. It assesses trauma cases like fractures. CBCT provides detailed 3D visualization of lesion size, location and impact.

Pediatric Dentistry:

DICOM images are used in pediatric dentistry to diagnose dental caries and impacted teeth or developmental anomalies. CBCT and panoramic radiographs assess mixed dentition and eruptive patterns.

Tele-Dentistry:

DICOM enables dental professionals to securely share images with specialists or laboratories and facilitating remote consultations and second opinions specifically in rural or underserved areas with limited specialist access.

Contraindications

• Pregnant patient
• Pediatric patient
• Unnecessary imaging for simple cases
• Claustrophobic patient
• Metallic artifacts reducing image quality
• Patients unable to remain still

Outcomes

Equipment

• Cone Beam Computed Tomography (CBCT) Scanner: The primary 3D imaging tool in dentistry. Capture volumetric data for the craniofacial area.
• Intraoral Radiography Equipment: It is used to capture localized pictures of teeth and surrounding structures.
• Panoramic and cephalometric X-ray machines: It produces 2D pictures of the complete jaw or craniofacial anatomy.
• Intraoral Scanners: These devices capture digital imprints of the oral cavity instead of traditional dental impressions.
• Computer-aided design and manufacturing (CAD/CAM) Software: It combines the DICOM pictures with digital impressions to enable virtual treatment planning.
• Picture Archiving and Communication Systems (PACS): It is a secure and centralized system for storing, managing and exchanging DICOM pictures.
• DICOM-Compatible Viewing Software: It is used for visualizing, manipulating and analyzing DICOM images. Multiplanar 3D reconstruction, anatomical structural assessments and virtual treatment planning tools are among the features.

Patient preparation

• Examine medical and dental history to establish imaging suitability and any contraindications.
• Confirm previous imaging to prevent needless radiation exposure.
• Describe the operation to the patient, address any radiation exposure concerns, and get informed consent.
• Remove metallic items to maintain image quality. Wear safety equipment like lead aprons and thyroid collars to reduce radiation exposure.
• Give clear positioning directions and stress remaining motionless throughout scans.
• If you have extreme anxiety, claustrophobia or difficulty staying still, you should consider limited sedation.

Patient position

Intraoral Radiography: Patient seated upright in the dental chair. Align the occlusal plane parallel to the floor and the midsagittal plane perpendicular to the floor. Place the sensor or film in the required area. Patient to close mouth gently without biting on the holder excessively.

Panoramic Radiography: Patient stands or sits upright in the panoramic X-ray machine. Place the chin on the chin rest, tilt the occlusal plane slightly downward. Use a plastic bite block to separate dental arches. Patient to remain still and hold tongue against the palate to reduce artifacts.

Cone Beam Computed Tomography (CBCT): Patient may be seated or standing. Use headrests and positioning aids to prevent movement. Patient to remain still and refrain from swallowing to avoid motion artifacts.

Cephalometric Imaging: Patient stands upright in the cephalometric machine. Align the Frankfort plane parallel to the floor.

Intraoral Scanning: Patient seated comfortably in the dental chair.

Technique

Cone Beam Computed Tomography (CBCT)

Step 1: Patient Preparation:

Obtain informed consent and remove metallic objects. Provide lead apron and thyroid collar for radiation protection.

Step 2: Equipment Preparation:

Ensure CBCT machine is functional and calibrated. Select proper field of view based on the region of interest. Choose resolution setting based on diagnostic needs.

Step 3: Patient Position:

Sit or stand patient and stabilize the head using positioning aids. Align Frankfort horizontal plane parallel to floor.

Step 4: Image Acquisition:

Start CBCT scan and monitor scan in real-time.

Step 5: Post Processing:

Reconstruct images by using specialized software to generate a 3D volumetric dataset. Export data in DICOM format for further analysis.

Step 6: Image Review:

View 3D images, perform multiplanar reconstruction and analyze region of interest for diagnosis and treatment planning.

Panoramic Radiography

Step 1: Patient Preparation:

Obtain informed consent and remove metallic objects. Provide lead apron and thyroid collar for radiation protection.

Step 2: Equipment Preparation:

Ensure panoramic machine is calibrated and functional. Set exposure parameters for patient’s age and size.

Step 3: Patient Position:

Patient to stand or sit upright in machine. Position chin on chin rest and stabilize head. Align Frankfort horizontal plane parallel to floor. Use bite block to separate dental arches. Confirm midsagittal plane is perpendicular to floor.

Step 4: Image Acquisition:

Activate panoramic X-ray machine for continuous image capture. Patient not to move or swallow during procedure.

Step 5: Post Processing:

Verify image for clarity and positioning. Save image in DICOM format for diagnosis or sharing.

Intraoral Radiography

Step 1: Patient Preparation:

Obtain informed consent and remove metallic objects. Provide lead apron and thyroid collar for radiation protection.

Step 2: Equipment Preparation:

Ensure X-ray machine and digital sensor are functional. Select appropriate exposure settings based on region and patient’s size. Position sensor in patient’s mouth for bitewing, peripheral and occlusal views.

Step 3: Patient Position:

Align patient’s head parallel to floor or midsagittal plane perpendicular to floor.

Step 4: Image Acquisition:

Aim X-ray beam at sensor using appropriate angulation. Activate X-ray machine to capture image.

Step 5: Post Processing:

Review image for accuracy and diagnostic quality. Store image in DICOM format for further analysis.

Picture Archiving and Communication Systems (PACS)

Image Acquisition:

Diagnostic pictures are obtained by DICOM compatible imaging modalities like intraoral radiography, panoramic radiography, CBCT imaging, cephalometric imaging and intraoral scanning. DICOM metadata is incorporated into the file to ensure traceability and data integrity.

Image Transfer to PACS:

PACS is a digital imaging system that allows healthcare providers, specialists or referring clinicians to access and analyze dental images and reports. It ensures central storage and retrieval of the data by transferring images from the imaging modality to the PACS server. Images are automatically converted into DICOM format using secure data transfer protocols and the imaging device, PACS server and connected systems are interconnected via a Local Area Network (LAN) or Wide Area Network (WAN). For secure cloud-based PACS encrypted internet connections are used to upload and store the data.

Storage and Archiving:

PACS stores imaging data in a centralized database for immediate or future access. Storage methods include on-site servers within the dental clinic or hospital, cloud-based storage and backup systems. Images are indexed based on patient id, study date, and image type for easy retrieval. Authorized users can retrieve and view images stored in PACS using DICOM-compatible software or viewers installed on PACS workstations.

Image Retrieval and Viewing:

Image retrieval and viewing features include Multiplanar Reconstruction (MPR), measurements, annotations, zoom and pan and image manipulation. Dentists or radiologists can analyze the retrieved images to make clinical diagnoses and plan treatments. PACS allows the generation of digital radiology reports which can include annotations, diagnostic findings and treatment recommendations. These reports can be stored alongside the corresponding DICOM images for easy reference.

Reporting and Diagnosis:

PACS enables seamless sharing of dental images and reports with other healthcare providers, specialists, or referring clinicians. Methods of sharing include within the clinic or network, external consultations, secure file transfers, cloud PACS platforms or encrypted removable media (e.g., CDs, USB drives). Teleradiology supports remote consultations by enabling specialists to access and analyze images from different geographic locations.

Data Security:

Data security and access control are ensured through user authentication, role-based access control, data encryption and audit logs. User authentication restricts unauthorized access, while data encryption protects data during storage and transmission. Audit logs record access and modifications made to patient imaging data.

Complications:

Radiation Overexposure: Using CBCT incorrectly or repeatedly can lead to increased radiation dosage for patients.

Metallic restorations: It can produce scatter and beam-hardening artifacts and reducing picture quality.

Motion Artifacts: Patient movement during imaging might reduce picture quality.

Misdiagnosis: It can occur while using DICOM software incorrectly or with poor skill.

Technical Errors: Improper DICOM export or corrupted files can hinder data sharing and storage

References

https://pmc.ncbi.nlm.nih.gov/articles/PMC3047213/

https://pubmed.ncbi.nlm.nih.gov/26464603/

References

https://pmc.ncbi.nlm.nih.gov/articles/PMC3047213/

https://pubmed.ncbi.nlm.nih.gov/26464603/