Periodontitis on X-ray: what it looks like on an image and CT scan

You have received an X-ray or computed tomography scan with a report of "periodontitis" and want to understand what exactly is shown on the film and what it means for the tooth. Periodontitis is inflammation of the periodontium in which the integrity of the ligaments holding the tooth in its socket and of the cortical bone plate is disrupted, and bone resorption also occurs — from minor extent to cyst formation. Let us break down how this looks on a conventional X-ray and on a CT scan.

What periodontitis is and why an X-ray is needed

Infectious periodontitis most often becomes a complication of caries — primary, when the process proceeds from untreated caries through pulpitis, or secondary, with an iatrogenic cause. There are also traumatic and medication-related variants. An X-ray is a painless examination: radiation passes through tissues, bones absorb it more strongly and appear white, soft tissues appear gray, and air appears black. The image is assessed by a radiologist, who passes the result to the treating physician; the image is used to assess the condition of the bone around the root apex.

What periodontitis looks like on an X-ray

In acute periodontitis, no radiological changes in the periodontium are noted — the diagnosis in this phase is made based on the clinical picture. Chronic forms look different. In fibrous periodontitis, the image shows deformation of the periodontal ligament space in the form of widening at the root apex, usually without resorption of the alveolar bone wall and root cementum. In the granulomatous form — a focus of bone rarefaction at the apex with indistinct contours or an uneven line, with destruction of cementum and dentin. Granulomatous periodontitis often runs asymptomatically.

Periodontitis on an image: what changes the doctor sees

The doctor correlates the complaints with the picture on the image. The reference points are as follows:

• widening of the periodontal ligament space at the root apex — typical of the fibrous form;
• a focus of bone rarefaction with indistinct contours — a sign of a granulomatous process;
• destruction of cementum and dentin at the tooth apex in the granulomatous form;
• absence of visible changes in an acute process.

Periodontitis on CT: when it is prescribed and what it shows

An X-ray examination may be part of computed tomography (CT). The images are described by a radiologist.

What may look like periodontitis on an image

A similar picture is produced by chronic gangrenous pulpitis — which is why the fibrous form can be difficult to diagnose. The conclusion based on the image is always correlated with examination, probing, and the tooth's reaction to cold and heat. The image itself is not a diagnosis but part of the examination.

When to see a dentist and what to ask

An urgent dental appointment is needed if a dental abscess is suspected: such symptoms include intense toothache or gum pain, swelling of the face or jaw, increased sensitivity to hot and cold, an unpleasant taste in the mouth, difficulty opening the mouth and chewing, enlarged lymph nodes in the neck, and high fever. Ask the doctor which form of periodontitis is visible on the image, whether a CT scan is needed, and what treatment options exist for this tooth — you make the decision together with the dentist.

A report of "periodontitis" by itself is not a reason to call an ambulance; 103 or 112 — if it is difficult to breathe, speak, or swallow, swelling or pain has appeared in the eye area or there are sudden vision problems, marked swelling in the mouth, or difficulty opening the mouth.

This material is for reference: it helps to understand the image but does not replace a consultation with a dentist, who will examine the tooth and discuss possible options with you.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer