Dental xray radiography techniques have come a long way since I graduated from uni in the early naughties. These days images are predominantly digital rather than film, and cone beam computed tomography (CBCT) scan is becoming increasingly useful in advanced dental diagnostics and treatment planning. Maxillofacial radiology has become its own dental specialty and I was lucky enough to hear from one of the most experienced in Australia, Dr Louise Brown, in Melbourne over the weekend at a full day seminar she presented .

Here’s a summary of my take home learnings from the symposium.

What you see is everything in dental radiographic interpretation

The quality of digital images these days is astounding, allowing differentiation between up to 65 thousand shades of grey. However the average human eye can only discern about 30-50 shades of grey. Optical illusions are common in human visual processing, making for fun games on social media, but a potentially troublesome source of trickery to all who use radiographs for professional decision making purposes. Knowing about these possible sources of visual imagery bias is important.

Anatomy confidence is your key to success

Brushing up on key head and neck anatomical structures and radiographic representation in healthy normal subjects is essential. As a general dental practitioner, consistent ability to determine normal from artefact, anomaly or abnormal is essential to interpretation success. Fortunately there are specialists such as Louise and others, along with histologists and surgeons to refer to for definitive diagnoses of anything we may pick up in routine or screening practice.

A good panoramic is an excellent tool

Bony pathology is best picked up by plain or 2D radiography, whereas soft tissue pathology is better distinguished by medical CBCT, MRI or ultrasound. A panoramic (OPG) gives a good overview of all structures of interest. Intraoral radiographs are excellent for increased specificity of focal areas. Beware of overprescribing CBCT:

• to those under age 16

• to those that need multidisciplinary specialist care

• to those whose likely treatment is simple and straightforward

Knowing the best dosage and sections to capture via CBCT for effective treatment delivery may be better chosen by the practitioner who will do the treatment.

However you can never be too cautious with dental implant and surgical treatment planning. Clinical, intraoral, panoramic and CBCT records and interpretation prior to planning and insertion are generally required.

Be systematic

Develop good radiographic habits: from viewing setup; to capturing methodology to minimise image overlap and artefacts; to a consistently sequential approach to viewing a radiograph. Patterns, symmetry and repetition through practice will vastly improve patient outcomes from area of interest along with incidental findings. Cortical bone integrity tracing cannot be overemphasised.

Have a standard formula approach to writing a radiographic report or referral letter - the more medical and clinical history included the better! Always record CBCT radiation datasets.

The more you know the more you see

Despite the emphasis on oral and craniofacial pathology during student learning days, clinical experience shows many dentists can count on one or both hands the number of really unusual findings that have walked through their door across an entire career. Any cobwebs on this body of knowledge is worth dusting off as the population continues to diversify and age.

The majority of dental pathology is acquired rather than developmental. Remembering the key diagnostic differentials between:

• radioluciencies, radiopacities, or mixed densities

• solitary or multiple lesions

• well or ill-defined lesions - especially moth-eaten or permeative presentations

• uni or multi-locular lesions

• odontogenic or independent presentations - lesion epicentre position is significant eg relative to the IAN (inferior alveolar nerve) in the mandible

• affected adjacent structures - expansile, erosive presentations vs displacing or resorptive processes

…will all help guide toward inflammatory, infective, benign or malignant differential indications and dictate ongoing management. Aunt Minnie may be rare, but is forever unmistakable!

Take home mantra

In the end, consistently advanced dental radiography reporting gets down to observation, deduction and knowledge. I’d add to that, prompt specialist opinion - when in doubt, it costs little to ask!

This seminar was most useful. Louise is a good presenter whose passion for her specialty can successfully carry the flow of an intense and largely theoretical day. I would have liked more detailed content on CBCT image capturing and interpretation techniques, particularly where different to standard 2D or plain film processes and in relation to field of view considerations. However Louise offers a separate full day course on dental CBCT alone. Louise kindly provided comprehensive lecture and case notes prior to the day. The location and catering was satisfactory. I happily recommend investing in this skills update course. I wrote this review of my own accord, without any incentivisation from the event organiser.

Dr Louise Brown offers an online maxillofacial radiology consulting service via www.teledent.com.au and various seminars to the dental profession.

By Christine May, dentist & health content creator. This article is for general educational purposes only and does not replace specific tailored advice on dental radiography by a specialist for a specific case.

This article first appeared on the FaceWell Blog www.facewell.com.au