What Happens at an Oral Cancer Screening (and Who Needs One)
Clinically reviewed by Dr. Abinaash Kaur, DDS, RCDSO, on 2026-10-19. Dr. Kaur is a general dentist in Toronto (Bloor West Village) registered with the Royal College of Dental Surgeons of Ontario.
An oral cancer screening is a look-and-feel check of your lips, mouth, throat and neck, and it happens during a routine dental exam. The Ontario Dental Association describes the exam done by your dentist as "fast, easy and painless" (Ontario Dental Association).
Nothing gets injected, and you don't need to prepare. Ontario has 4 free cancer screening programs, for breast, colon, cervical and lung cancer, and none of them is for the mouth (Ontario government). So for most people, the check at the dental exam is the oral cancer screening.
What is the dentist doing when they look and feel around your mouth?
Most people think a dental exam is about teeth. Here's what happens instead.
The Canadian Dental Association lists "early signs of mouth or throat cancer, such as white lesions or blocked salivary glands" among the things a dentist is looking for during an exam (Canadian Dental Association). The same page describes the dentist feeling the glands and lymph nodes in your neck for signs of inflammation.
A review of screening programs around the world found the same basic pattern. Most programs included looking at and feeling the lips, the inside of the mouth and the parts of the throat you can see, and some also checked the neck for swellings (review of oral cancer screening programs, PubMed).
In plain terms, a dentist looks and feels for:
- Patches of a different colour, especially white or red
- Lumps, or spots where the texture has changed
- Sores that haven't healed
- Swollen or firm glands under the jaw and down the neck
The exam starts before anyone looks in your mouth, with your health history. The CDA asks patients to mention if they smoke or chew tobacco, "which increases the likelihood of oral cancer" (Canadian Dental Association). That question isn't a judgment. It changes what we pay attention to.
Why can a dentist spot things you can't?
You're not supposed to catch everything yourself. Your dentist sees your mouth under bright light, from angles you can't get in a bathroom mirror. The Ontario Dental Association says it directly: "They may notice subtle changes in the mouth that you won't" (Ontario Dental Association).
The Public Health Agency of Canada says oral cancer can often be treated successfully if it's caught early, and if it isn't treated early it can spread and be harder to treat (Public Health Agency of Canada). A study of Ontario dentists notes that more than half of oral cancers are diagnosed at an advanced stage, largely because people come in late (Journal of the Canadian Dental Association).
That's information, not a scare. It's the reason a regular look by a trained eye matters.
Is a screening necessary if you don't smoke?
Yes. Tobacco and alcohol are the big risk factors, but they aren't the whole story.
The Public Health Agency of Canada says about 25% of oral cancers occur in people who don't smoke or drink alcohol (Public Health Agency of Canada). It also says people over 45 are at higher risk, and people over 60 have the highest incidence.
Here are the main risk factors the Canadian sources name:
- Tobacco and alcohol together. The ODA says using them together raises the risk more than using either one alone (Ontario Dental Association).
- Heavy drinking on its own. PHAC says the increase in risk tracks the amount of alcohol and how long it's used (Public Health Agency of Canada).
- Sun on the lips. Most lip cancers occur on the bottom lip, likely because it gets more sun (Ontario Dental Association).
- HPV, the human papillomavirus, covered in the next section.
Sex matters too. PHAC says the ratio of oral cancer in men compared with women used to be 6 to 1, and it's narrowing, now closer to 2 to 1 (Public Health Agency of Canada).
How does HPV fit in?
HPV mostly shows up in throat cancer, not cancer at the front of the mouth. The throat area here is the oropharynx (the back of the tongue, the tonsils and the throat wall behind them).
Here are the Canadian public health figures:
- HPV causes 60% to 73% of throat (oropharyngeal) cancers, and throat cancer is now the most common HPV-related cancer in Canada (Public Health Agency of Canada, HPV).
- In Canada, the share of throat cancers that were HPV-positive rose from 47% in 2000 to 74% in 2012 (Public Health Agency of Canada).
- Counting mouth and throat cancers together, about 25% to 35% in Canada are related to oral HPV infection (the share is higher for throat cancers alone, as above), and in 2012 the rate of HPV-associated throat cancer was more than 4.5 times higher in males than females (Canada Communicable Disease Report).
The good news is the HPV vaccine. PHAC says it can reduce your risk of throat cancer, and people who already have HPV may still benefit (Public Health Agency of Canada). Ontario students in grades 7 to 12 can get it for free (Ontario government). As of the 2020 federal report, Canadian dentists can't give the shot, so ask your doctor or a nurse about the vaccine (Canada Communicable Disease Report).
Part of the screening covers the tonsil area, which can make people nervous about normal bumps back there. Our guide to tonsil stones explains one common, harmless thing you might spot.
What would make a dentist look twice?
The two-week rule is the one to remember.
PHAC says to see an oral health or other health professional right away for sores or patches in the mouth or on the lip that don't heal within 2 weeks (Public Health Agency of Canada).
Other signs PHAC lists include:
- Dark red or white patches in the mouth, or on your lips or tongue
- Lumps, or changes in the texture or colour of the mouth tissues
- Unexplained bleeding in the mouth
- Numbness, tenderness or pain in the mouth or tongue for no clear reason
- Trouble chewing, swallowing, speaking, or moving your jaw or tongue
- A sore throat that won't go away, hoarseness, or a feeling that something is caught in your throat
- Swelling of the jaw that makes dentures fit poorly
Plenty of mouth sores have everyday causes, like canker sores and cold sores, which heal on their own. Our post on canker sores versus cold sores explains how to tell them apart and when one is worth a visit.
What happens next if a spot looks suspicious?
A finding at a screening isn't a diagnosis. The Ontario government puts it plainly: an abnormal screening result does not mean you have cancer, but it does mean you may need more tests (Ontario government).
If a spot needs a closer look, the CDA describes the next steps. Part of the area may be removed and looked at under a microscope, which is called a biopsy, and imaging tests such as X-rays, ultrasound, CT or MRI may be used (Canadian Dental Association).
That work often happens with a specialist, such as an oral surgeon, an oral pathologist or a head and neck specialist. In a small survey of 91 Toronto dentists, over 80% said they referred to a specialist when they found a suspected lesion (survey of Toronto dentists, PubMed).
If a spot has been bugging you, ask about it, even if it feels minor. That question is the reason the check exists.
Do special lights or rinses find more?
You may have heard of glowing lights, dyes or brush tests used alongside the exam. What does the evidence say?
A Cochrane review found no evidence to support add-on tools like toluidine blue dye, brush biopsy or fluorescence imaging as a screening tool to reduce deaths from oral cancer (Cochrane review, PubMed).
A 2026 review of light-based tests found, with low certainty, that they could pick up most abnormal spots in people who already had a visible change, but they could also produce many false-positive results (light-based tests review, PubMed). The authors called the absence of evidence in people without visible changes problematic.
One study of lesions that looked harmless found these lights didn't help find precancer or cancer, and warned that a negative light result could give patients a false sense of security (PubMed).
What about the plain look-and-feel exam? The same Cochrane review rests on one large trial, and its authors flag a high risk of bias. Among high-risk people who used tobacco or alcohol or both, the screened group saw a 24% reduction in deaths from oral cancer (Cochrane review, PubMed). Across everyone screened, the difference in deaths wasn't statistically significant.
How often should you have one, and is it covered?
The screening rides along with your exam, so the real question is how often you have an exam. The ODA says to visit your dental office at least once per year for an oral exam (Ontario Dental Association). The CDA says the interval depends on your oral health needs, and for many people that means every six months (Canadian Dental Association).
Been away from the dentist for years? Our post on going back after a long gap walks through that first appointment, no lecture included.
What about the Canadian Dental Care Plan? The CDCP covers dental exams, including complete, routine, specific and emergency exams, and describes these diagnostic services as helping detect mouth conditions like cancer earlier (Government of Canada, CDCP). The plan may not pay the full amount, and you may have a co-payment based on your adjusted family net income.
In a 2020 survey of Ontario dentists, some named the lack of a separate oral cancer examination fee code as a barrier to screening (Journal of the Canadian Dental Association). For private insurance, your plan booklet is the place to confirm how exams are covered.
Can you check your own mouth between visits?
Yes, and PHAC lays out the steps (Public Health Agency of Canada). Try this, in good light with a mirror:
- Feel your neck and under your lower jaw for lumps.
- Look at and feel your lips, gums and the roof of your mouth for anything unusual.
- Stick out your tongue and look at the top and the bottom.
- Pull your cheeks outward to see the inside of your cheeks, your back gums and the back of your throat.
- Lift your lips to see the inside of them and your front gums.
Oral cancer isn't the only way your mouth ties into the rest of your health. Our post on the mouth as the front door to your body goes into the bigger picture.
Frequently Asked Questions
Q: Does a dental check-up include an oral cancer screening? It should. The Canadian Dental Association lists early signs of mouth or throat cancer among what a dentist looks for during an exam, along with feeling the glands and lymph nodes in your neck (Canadian Dental Association). If you're not sure it was done, ask.
Q: Does an oral cancer screening hurt? No. The Ontario Dental Association describes the oral cancer exam done during a routine dental exam as fast, easy and painless (Ontario Dental Association). It's a visual check plus gentle pressure with gloved fingers.
Q: How often should you get an oral cancer screening? It comes with your dental exam. The ODA recommends an oral exam at least once a year (Ontario Dental Association), and the CDA says the interval depends on your oral health, which for many people means an exam every six months (Canadian Dental Association).
Q: Is oral cancer screening covered by the CDCP? The Canadian Dental Care Plan covers dental exams, which is where the screening happens, though it may not pay the full amount and some people have a co-payment (Government of Canada, CDCP).
Q: What are the early signs of mouth cancer? A sore or patch that doesn't heal within 2 weeks, red or white patches, lumps, unexplained bleeding, numbness, or trouble swallowing are all on the Public Health Agency of Canada's list (Public Health Agency of Canada).
Q: Does HPV cause mouth cancer? HPV mainly drives throat cancer. The Public Health Agency of Canada says HPV causes 60% to 73% of throat (oropharyngeal) cancers, and that throat cancer is now the most common HPV-related cancer in Canada (Public Health Agency of Canada, HPV).
Reviewed by Dr. Abinaash Kaur, B.Sc., DDS (University of Toronto Faculty of Dentistry), who has practised general and family dentistry in Bloor West Village for about 25 years. This article is general oral health information, not a diagnosis, medical advice, or a substitute for an examination.
Noticed a sore that won't heal, or just want to know your mouth has been checked properly? We're at 750 Annette Street in Bloor West Village, serving the Junction, High Park, and Baby Point. Book an exam with The Village Dentist and we'll take a careful look, lips to neck.
