How to prepare for a dental X-ray? Fasting, metal items and other questions
You do not need to come for a dental X-ray on an empty stomach — none of the periapical, panoramic or CBCT images have anything to do with the digestive system, and eating does not affect the quality of the image. In practice, preparation comes down to three things: removing the metal items that fall within the imaging area (earrings, necklaces, piercings, hair clips, glasses, removable dentures), telling your dentist if there is any chance you are pregnant, and staying still during the scan. If a particular procedure has any additional requirement, your dentist will tell you separately.
Why does the question of coming on an empty stomach come up?
The habit of fasting before tests such as blood analysis, endoscopy or general anaesthesia creates the belief that you must fast before every medical procedure. A dental X-ray, however, uses radiation to produce an image of the teeth, the jawbone and the surrounding tissues; the gastrointestinal system plays no part in the process. You can eat whatever you like; the only recommendation is to brush your teeth and rinse your mouth before you come — food debris packed between the teeth can sometimes create a small shadow on the image. After a very heavy meal, the rotation of the panoramic machine can make some patients feel nauseous — a light meal is more comfortable. If treatment under anaesthesia is planned after the examination, your dentist may give separate advice about eating; this is not related to the X-ray itself.
Why do metal items have to be removed?
This is not simply a request from your dentist, it is a technical necessity. Metal — gold, silver, steel, titanium — absorbs almost the entire X-ray beam; a bright white area in the shape of the object, that is a metal artefact, appears on the image. The artefact carries no clinical information at all; on the contrary, it hides the structures underneath — tooth decay, inflammation at the root tip, changes in the bone. An example: if a patient with inflammation at a root on the right side of the lower jaw is wearing a large earring in the right ear, the artefact on the panoramic image falls exactly in that area — the dentist sees a white patch, not the inflammation. After that, either the image has to be repeated (additional radiation) or the diagnosis is delayed.
Glasses, earrings, necklaces, piercings
- Earrings — long dangling earrings in particular fall over the lower jaw area; on a panoramic image they can cover the tooth roots on both sides.
- Tongue and lip piercings — a tongue piercing covers the root area of the lower front teeth, and a lip piercing covers the crowns of the front teeth; eyebrow and nose piercings usually do not interfere with dental X-rays, but they can create artefacts within the wider CBCT field.
- Necklaces and chains — can cover the neck area on panoramic and CBCT images.
- Hair clips and metal buckles — fall over the upper jaw and sinus area; this is especially important for CBCT.
- Metal-framed glasses and hearing aids — are removed if they fall within the imaging area.
Taking them off takes 1–2 minutes; place your belongings in the box provided at the clinic.
Removable dentures and appliances
Because full or partial removable dentures carry metal clasps and retaining elements, they are taken out before the scan. Removable orthodontic appliances (plates, retainers) are also removed. Constructions that cannot be removed — permanent crowns and bridges, implants, braces, amalgam fillings — stay in place; they can create artefacts too, but your dentist knows where they are and interprets the image accordingly; there is no need to worry.
Why are artefacts more critical on CBCT?
On a panoramic image the artefact appears in a single projection; because CBCT creates a volumetric image, the artefact from a single metal object spreads across hundreds of slices. That is why, before CBCT for implant planning, the TMJ and wisdom teeth, the removal of metal items is taken even more seriously.
Telling your dentist about pregnancy
If you are pregnant or think you might be, be sure to tell your dentist before the scan. The dose of a dental X-ray is very low, but elective images are usually postponed, while in urgent cases they are taken with special protection — the decision is made by your dentist. In detail: Dental X-rays during pregnancy.
Information about medicines and medical conditions
An X-ray does not require any special preparation, but telling your dentist about the medicines you take and any existing conditions is useful for your treatment plan.
Preparing children
Children do not need to come on an empty stomach either; the main points are psychological preparation and staying still. Explain to your child in advance that the examination is painless and that the machine does not touch them; if they move, the image comes out blurred and has to be repeated. Hair clips, hair accessories and metal buckles on clothing are often forgotten — remove them before the scan. For a child who is afraid of the clinic environment, bringing them in once beforehand to get used to it can help. About doses and protocols in children: Are dental X-rays safe for children?.
What can you expect from each type of image?
- Periapical (small) X-ray — a sensor is placed in the mouth, 1–2 minutes; brushing your teeth before you come is enough.
- Panoramic X-ray — the machine rotates around your head and the scan takes 15–20 seconds; you will be asked to bite on the bite block and stay still, place your tongue against the palate and hold your breath (What is a panoramic X-ray?).
- CBCT — the head is stabilised with a head holder, the exposure takes 15–25 seconds and the whole procedure a few minutes; metal items must be removed.
None of them require fasting or lengthy preparation; our dental X-ray service covers all of these methods.
Frequently asked questions
Q: Do I need to come for a dental X-ray on an empty stomach? A: No. Fasting is not required for periapical, panoramic or CBCT images; eating does not affect the quality of the image.
Q: What can I eat before an X-ray? A: Anything you like. The only recommendation is to brush your teeth and rinse your mouth before you come.
Q: Why do metal items have to be removed before an X-ray? A: Metal absorbs the beam and creates a white artefact on the image, hiding the teeth, bone and inflammation underneath — this makes diagnosis difficult or means the image has to be repeated.
Q: Do earrings or a tongue piercing interfere with an X-ray? A: Yes — earrings can cover the lower jaw area and a tongue piercing the roots of the lower front teeth. Remove them before the scan.
Q: I have a permanent prosthesis, an implant or braces — what should I do? A: Nothing; these are not removed. Your dentist knows where these constructions are and interprets the image taking the artefacts into account.
Q: Can pregnant women have dental X-rays? A: Elective images are usually postponed; in urgent cases the dentist can assess the risk-benefit balance and take the image with special protection. Always let us know that you are pregnant.
Q: How should children prepare for a dental X-ray? A: Fasting is not required. Explain to your child that the examination is painless, remove hair clips and help them stay still during the scan.
Author: Dr. Bakhtiyar Aliyev | Smile by Dr. Bakhtiyar, Baku. This article has been reviewed by a dentist.
For a professional dental X-ray in Baku, get in touch with us — book online or give us a call.
Sources
- X-Rays/Radiographs — Oral Health Topics — American Dental Association
This article is for general information only and does not replace an individual diagnosis, examination or treatment. Consult a doctor for a decision about your case.