CONE BEAM VOLUMETRIC IMAGING IN CLINICAL PRACTICE
Nothing has captured the dental profession’s imagination in the past few years like the introduction of cone beam volumetric imaging (CBVI), sometimes referred to as cone beam computerized tomography (CBCT) or cone beam volumetric tomography (CBVT). These machines’ image acquisition process differs from that of traditional medical computerized tomography (CT) scanners in that the patient is not usually supine, the image gathered is in a voxel (volume element) format, the x-ray dose absorbed by the patient is substantially lower, appointment availability is much easier, and it is less expensive. In short, although the imaging modality produces significant data volumes like medical CT, it is vastly superior to traditional CT data for specific dental applications.
Box 1-1 Applications of CBVI
3-D virtual model construction
Airway studies related to sleep apnea
Bone structure (dehiscences, fenestrations, and/or periodontal defects in adults)
Impaction related to orthodontics
Implant site assessment including temporary anchorage devices
Inferior alveolar nerve location for third molar extraction
Odontogenic lesion visualization
Other computer-aided design/computer-assisted manufacture devices
Paranasal sinus evaluation
Space analysis (1:1)
Surgical guide fabrication
Temporomandibular joint visualization
Dentists and dental specialists have seen and appreciated the incredibly precise and profound information produced by CBVI scans, and they are realizing that the data they receive will influence their treatment decisions like no other imaging modality used in the profession in the past 100 years. CBVI makes clinical decision making easier and more precise, patient treatment decisions more accurate, and visualization of the x-ray data more meaningful. Dentistry is moving away from “radiographic interpretation” and into “disease visualization,” and it could not have come at a better time.
THE NEAR FUTURE
The evolution of implant technology, the technical skills and training of dental professionals, and patients’ desire for more permanent and predictable restorative solutions to missing teeth all ensure that implant dentistry will remain the largest growth market for dental professionals and commercial vendors for at least the next decade. I would predict that by 2013, the reconstructed data in 2-D/3-D grayscale and color formats from CBVI machines will become the standard of care for displaying patients’ radiographic information in cases of preoperative implant site assessment, implant placement, and follow-up radiographic assessment. CT, plain film imaging, and digital imaging modalities will probably become obsolete, at least for implant dentistry applications.
The additional applications for CBVI encompass most of the procedures clinicians perform in their offices. Some applications for CBVI are listed in Box 1-1; examples of many of these are discussed in chapters 4 to 14. Additional applications will undoubtedly follow as clinicians learn about and begin to appreciate the incredibly beneficial data this imaging modality delivers for improved treatment planning and clinical decision making.
PRESENT CONSIDERATIONS FOR CBVI
To date, I have read, or interpreted, almost 3,000 CBVI cases for my dental colleagues. I practice my specialty of oral and maxillofacial radiology from my home in a dedicated radiology office environment via the Internet. I continue to interpret images and create reports for clinicians while I travel, speak, and consult. I operate in the same manner as my medical radiology colleagues and practice my specialty from virtually anywhere in the world because of global Internet access.
Just as there are many different models on the market, I receive data volumes to interpret through many different avenues. Gone are the days when we relied on 2-D grayscale single images attempting to represent 3-D structures, viewed on lightboxes under poor lighting conditions, to help us make our clinical treatment decisions. It is now possible to have 2-D or 3-D color “renderings” of each patient’s anatomy and signs of clinical diseases/disorders.
Figure 1-1 shows the CBVI machine’s broad capabilities and power. Whether you are considering purchasing a machine for image acquisition in your practice or are simply accessing this technology by requesting a scan, you should consider the following important questions:
- How much data (number of images) do you need?
- How large an area do you wish to evaluate?
- Do you need s/>