In this episode, Dr Clifford Yudelman introduces co-discovery, the principle that a patient is an informed partner in their own care rather than a passive bystander.
He walks through how to make sense of a dental x-ray: what the light and dark areas mean, how cavities, bone loss, abscesses, tartar and dense restorations appear, and where AI tools such as Diagnocat fit in.
The aim throughout is to replace fear with clarity, because when patients can see what is happening in their own mouth, they understand it, trust it, and act on it sooner.
Questions and Answers
Question 1. What is co-discovery, and what should I be looking for on my own x-ray? (1:04)
Co-discovery, an idea from the American dentist Dr Bob Barclay in the 1950s, means the patient is an informed partner who understands the story their mouth is telling rather than diagnosing themselves. Start by orientating yourself: find the crowns, the roots and the surrounding bone. A healthy x-ray shows well-defined teeth and bone that hugs the roots closely, so once you know what normal looks like, abnormal findings make sense.
Question 2. What is the difference between the white areas and the dark areas on an x-ray? (2:40)
White areas are dense structures that block radiation: enamel, bone, and especially metal fillings or inlays. Dark areas are where the x-rays pass through easily, like the air between teeth, and they also flag less dense problems such as cavities or infection in the bone. With digital x-rays you can adjust the brightness to see these contrasts more clearly.
Question 3. How does a cavity look on an x-ray compared to a healthy tooth? (4:34)
A healthy tooth has a smooth, uniform outline with no dark shadows in the enamel, while a cavity usually shows as a dark triangle or shadow between the teeth or under an existing filling. Early decay can be subtle, and not all cavities show on x-rays, so the image only works alongside a clinical exam. Five shadows do not automatically mean five fillings.
Question 4. Can I spot bone loss on my own x-rays? (6:02)
Yes. In a healthy mouth the bone sits one or two millimetres below where the root meets the crown, so bone loss shows as a lowering of that level and a longer-looking root. Seeing it turns the abstract idea of gum disease into something visible, which makes patients far more likely to act.
Question 5. How do you spot an abscess or infection at the root tip? (6:51)
An abscess often appears as a dark circular or irregular area around the root tip, marking bone destruction from a chronic infection. Early ones can be missed on a flat 2D x-ray, which is why a CBCT often reveals a shadow that was not obvious before. Good diagnosis correlates the imaging with the symptoms, never a single snapshot.
Question 6. What do bright white streaks or shapes usually mean? (7:42)
Usually dense, man-made things: implants, crowns, posts and fillings, with white fillings slightly less opaque. A full crown can hide recurrent decay underneath, so we adjust how often we x-ray depending on how much restorative work is present. CBCT is excellent for roots and bone but is sensitive to metal, which is one area where AI helps cut through the streaking.
Question 7. How can I tell if there's tartar or calculus on an x-ray? (9:18)
Tartar is the chalky white build-up on teeth; above the gum it is mainly cosmetic and simply cleaned off. Below the gum it shows clearly on an x-ray, almost always alongside bone loss, and it is often invisible in the mirror, especially in smokers with healthy-looking gums. Seeing that hidden tartar and the bone it is destroying is what motivates people to act.
Question 8. Why do some teeth look like they're floating? Does it mean they're loose? (10:41)
A floating tooth has almost no bone around it, usually from very advanced gum disease in someone who has gone years without care. Most of these teeth cannot be saved. If two or three are floating, the rest are often not far behind.
Question 9. How does AI help patients understand their x-rays better? (11:57)
Software like Diagnocat colour-codes and flags abscesses, cavities and tartar, and even picks up wear or abfraction, supporting the conversation without replacing the dentist's judgment. Sometimes it catches what I would have missed, and sometimes I see what it missed. It has to be used responsibly, because turning up its sensitivity to claim a patient needs fifteen fillings is exactly the over-diagnosis to guard against.
Question 10. Why is it important for patients to see the x-ray, not just be told what's wrong? (14:05)
I take photos, a 3D scan and x-rays, run them through AI, then sit with the patient and look at everything together as part of a ninety-minute exam. This is discovering before diagnosing, and it lets us agree what genuinely needs treating and what can be left alone. Being told creates dependency, but seeing creates understanding, which helps patients accept care early while problems are still small.
Closing Thoughts
Co-discovery turns the abstract into the visible. When patients sit down and look at their own x-rays, photographs and scans alongside the dentist, decisions become shared rather than imposed, treatment is accepted earlier while problems are still small, and anxiety drops. Being told creates dependency; seeing creates understanding, and that understanding is what protects a patient's teeth, health and finances over a lifetime. To learn more or to book a full examination, visit OptiSmile.co.za.
Further Resources
Secrets of Your Teeth Exposed Through Dental X-Rays - podcast companion on the types of dental x-ray and what each one reveals: https://optismile.co.za/blog/secrets-of-your-teeth-exposed-through-dental-x-rays/
Are All These X-Rays Necessary? - on x-ray frequency, CBCT, and avoiding unnecessary imaging: https://optismile.co.za/blog/x-rays-dentist-gives-necessary/
The Ultimate Guide to Dental Check-Ups - what a thorough check-up includes, x-rays, and AI-assisted review: https://optismile.co.za/blog/the-ultimate-guide-to-dental-check-ups/
Digital Dentistry: AI, 3D Printing and the Future of Your Smile - how OptiSmile uses Diagnocat and digital scans to show patients their own findings: https://optismile.co.za/blog/digital-dentistry-ai-3d-printing-the-future-of-your-smile/
Orthophos 3D X-Ray (CBCT) - the low-radiation 3D x-ray technology used at OptiSmile: https://optismile.co.za/dental-technology2/orthophos-3d-x-ray/
Book an appointment - contact OptiSmile in Sea Point, Cape Town: https://optismile.co.za/contact-dentist-cape-town/
OptiSmile - practice home, articles and online booking: https://optismile.co.za/
Diagnocat - the AI dental imaging software referenced in this episode: https://diagnocat.com
Disclaimer: The content provided in this podcast, "Save Your Money Save Your Teeth" on Medical Mondays, is for informational and educational purposes only. It is not intended to serve as dental or medical advice. The insights and opinions expressed by Dr. Clifford Yudelman and any guests are designed to foster a better understanding of dental health, preventive measures, and general well-being, but should not be interpreted as professional dental or medical recommendations. Dr. Clifford Yudelman does not diagnose, treat, or offer prevention strategies for any health conditions directly through this podcast. This platform is not a substitute for the personalized care and advice provided by a licensed dental or healthcare professional. We strongly encourage our listeners to consult with their own dental care providers to address individual dental health needs and concerns. The information shared here aims to empower listeners with knowledge about dental health but must not be used as a basis for making health-related decisions without professional guidance. Your dental care provider is the best source of advice about your dental and overall health. Please always seek the advice of your dentist or other qualified health professionals regarding any questions or concerns about your dental health.
