Different dental images answer different questions. A three-dimensional scan is not automatically the best first test.
Why different dental tests are used
Dental imaging ranges from small intraoral X-rays to panoramic OPG images and three-dimensional CBCT. The best examination depends on the tooth, region, suspected problem and treatment being considered.
Intraoral dental X-rays
Bitewing and periapical X-rays provide detailed two-dimensional views of a small area. They are commonly used for tooth decay, fillings, root tips, periodontal bone levels and local dental disease. They generally use less radiation than CBCT and are often the appropriate first test.
Read more about Dental X-Ray at MBR Health.
OPG or panoramic X-ray
An orthopantomogram, or OPG, provides a broad two-dimensional overview of the teeth, jaws and surrounding structures. It is commonly used for wisdom teeth, dental development, general jaw assessment and orthodontic planning. Because structures overlap in a 2D image, an OPG may not answer every question.
Cone beam CT
CBCT reduces the problem of overlapping anatomy by creating a three-dimensional volume. It can show the position of teeth and roots relative to nerves, sinuses and surrounding bone and allows measurements in multiple planes.
The additional 3D information comes with more radiation than most routine 2D dental X-rays, so CBCT should be selected when the added information is likely to affect diagnosis or management rather than simply because the technology is available.
When another modality is better
Medical CT is generally preferred when major trauma, acute infection, broader head-and-neck anatomy or intravenous contrast assessment is required. Spectral CT may provide additional iodine and material information in selected medical indications. 3T MRI may be required for the TMJ disc, nerves, marrow or soft tissues, while ultrasound can assess selected superficial soft tissues, glands and lymph nodes.
Frequently Asked Questions
Is CBCT always better than an OPG?
No. An OPG may answer a broad dental question with less radiation. CBCT is useful when 3D localisation or detailed bony anatomy is needed.
Why might my dentist request both?
The OPG may provide the overview, while a focused CBCT answers a specific planning question that cannot be resolved confidently on the 2D image.
Can CBCT find cavities?
CBCT is not usually the first or best test for routine tooth decay. Clinical examination and appropriate intraoral X-rays are generally more suitable.
Related Patient Guides
See the full MBR Health Patient Guides library for simple information about imaging, preparation, safety and results.
- PG5001 Cone Beam CT: What to Expect Before, During and After Your Scan
- PG5003 Cone Beam CT Radiation Dose and Safety
- PG5004 Cone Beam CT for Dental Implant Planning
- PG5005 Cone Beam CT for Wisdom Teeth and Oral Surgery
- PG5006 Cone Beam CT for Root Canal and Endodontic Assessment
- PG5007 Cone Beam CT for Orthodontics and Impacted Teeth
- PG5008 Cone Beam CT for the Jaw Joint and Facial Skeleton
- PG5009 Sinuses, Airways and Incidental Findings on Dental CBCT
- PG5010 What Cone Beam CT Can and Cannot Show
Related MBR Health services: Dental X-Ray • 3T MRI • Spectral CT • Ultrasound
More FAQs: For other common imaging and appointment questions, visit the MBR Health FAQs page.
| Important: The most detailed test is not always the most appropriate test. Imaging should be selected to answer the specific clinical question with the lowest reasonable radiation exposure. |
PATIENT GUIDE • PG5002 | Patient information: CBCT vs OPG Gold Coast
Comparing the best radiology on the Gold Coast and Brisbane for dental imaging?
Patients comparing elite, expert or advanced radiology services should look for the right test rather than simply the most complex test. MBR Health uses dental X-ray, OPG, cone beam CT and, when clinically appropriate, 3T MRI, Spectral CT or ultrasound so the imaging pathway can be matched to the problem. For patients travelling from Brisbane, MBR Health’s imaging practice is located on the Gold Coast.
Explore: Dental X-Ray • X-ray & Dental Imaging • 3T MRI
