October 26, 2026
Most mouth ulcers are minor and clear up by themselves. According to the NHS, they are common, usually heal within a week or 2, and are rarely a sign of anything serious. The point to remember is the three week mark: the NHS says to see a GP or dentist if you have a mouth ulcer that lasts longer than 3 weeks.
That advice exists because an ulcer that stays put is worth having looked at, not because it is likely to be serious. Only an examination can tell you what your own ulcer is.
A mouth ulcer is a sore that forms inside the mouth. According to the NHS, ulcers usually appear on the cheeks or lips, though they can also form on the tongue, and you can have more than one at a time. They are typically white and circular, and some are large. They are not contagious.
Many ulcers have an everyday cause. The NHS lists several that you may be able to avoid:
If you wear dentures and an ulcer keeps appearing in the same spot, mention it to your dentist. If a rough filling is the likely cause, your dentist can talk through replacing it, including with white fillings.
According to the NHS, you should see a GP or dentist if the ulcer:
Three weeks is the figure used by the NHS, and Cancer Research UK uses the same one in its referral guidance: a GP may refer you urgently to a specialist for unexplained mouth ulcers that do not go away after 3 weeks. Bupa describes a non healing ulcer in the same way.
The NHS says GP or dentist, so either is a sensible first stop. Dentists look inside the mouth as part of their work, and the Oral Health Foundation says they are trained to spot early changes. If you already see a dentist regularly, that is often the quickest route.
This is the part many people worry about, so it is worth being clear and calm. The NHS says that a long lasting mouth ulcer is sometimes a sign of mouth cancer, and that it is best to get it checked.
No two visits are identical, and your dentist will decide what is right for you. In general, this is what to expect.
A dentist will usually ask about your symptoms, such as how long the ulcer has been there, and then look at the ulcer and the rest of your mouth. Cancer Research UK says that a GP asks about your symptoms and may examine you, and the same approach applies in a dental chair.
Part of the visit is looking for something simple that might explain an ulcer, such as a sharp or broken tooth edge, a rough filling or a denture that rubs. The NHS lists these as causes, and the Oral Health Foundation says an ulcer from a minor injury usually heals once the cause is removed.
At our clinic, the dental examination includes a check of the teeth, gums, tongue and cheeks, and the new patient examination includes oral cancer screening. New patients complete a short two step new patient registration form with medical questions before the first visit, which helps the dentist see the full picture.
The NHS says avoiding irritants should help ulcers heal, ease the pain and lower the chance of them coming back. Its suggestions include:
The NHS says a pharmacist can recommend products that do not need a prescription, including antimicrobial mouthwash, painkillers, corticosteroid lozenges and salt mouthwash. To make a salt mouthwash, the NHS says to dissolve half a teaspoon of salt in a glass of warm water, rinse it around your mouth and then spit it out rather than swallowing it.
The NHS includes regular dental check ups in its advice for lowering the chance of ulcers returning. Check ups give your dentist the chance to see the whole mouth, and we cover how often to see a dentist in more detail. If you would like a professional clean, a hygiene appointment is also available.
You can look at our examination fees, and your dentist can explain what the visit involves when you book.
Most ulcers can wait for a routine appointment. If an ulcer is very painful, bleeds, or seems to be linked to a broken tooth or a lost filling, you may want to be seen sooner, and our emergency appointments are offered for pain and broken teeth.
The NHS says mouth ulcers should clear up on their own within a week or 2. Avoiding irritants such as spicy, salty or acidic food can help. If an ulcer is still there after 3 weeks, see a GP or dentist.
The NHS says to see a GP or dentist if a mouth ulcer lasts longer than 3 weeks, is different from your usual ulcers, bleeds, or gets more painful and red. The Oral Health Foundation also says to have an ulcer checked if ulcers keep returning or you feel unwell.
Sometimes, which is why it is checked. The NHS says a long lasting ulcer is sometimes a sign of mouth cancer and that it is best to get it checked. Cancer Research UK says most people with these symptoms do not have mouth cancer, and other causes are far more common.
The NHS lists biting your cheek, ill fitting dentures or braces, rough fillings, sharp teeth, hot food or drinks, irritating toothpaste, stress and tiredness among the common causes. Hormonal changes, family genes, low vitamin levels, some medicines and some medical conditions can also play a part.
The NHS suggests a soft toothbrush, cool drinks through a straw, softer foods and avoiding spicy, salty, acidic or crunchy foods. A pharmacist can recommend mouthwash, painkillers, lozenges or a salt mouthwash, and can advise on which suits you.
No. The NHS says mouth ulcers are not contagious. Cold sores are different and appear on or around the lips, so they are described separately by the NHS.
The dentist will refer you to a specialist. According to Cancer Research UK, a dentist who suspects cancer should refer you to a cancer specialist. The NHS says the main test is taking a small sample of cells for testing, and results usually arrive within 2 weeks.
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4,8
I could not be more satisfied with my experience at Maida Smiles - A special mention to Dr Gurteurez who is one of the most friendly and professional dentists I have ever met
Adam
I had my first visit and the team was very warm, caring and professional. The online booking platform makes it very easy to arrange your appointment. Doctor Pedro made me feel comfortable despite this being my first appointment since Covid. He is incredibly knowledgeable and offers you the best treatment for your specific condition. I would highly recommend them
Gian Paolo Ziletti
Professional. Friendly. Informative. Maida Smiles offers great dental services including cleanings, oral surgery and realignment. I feel very lucky to have them so close by. I had an appointment just this week that was quick, thorough and safe.
Emily Chmura
Being very nervous about using dentists after a terrible experience when I was younger, I came to Maida Smiles and loved the calm patient demeanour of Pedro. You can clearly see Pedro and the team take pride in what they do and are perfectionists. The whole experience was great and I will never go to another dentist again.
Reena Nathwani
Delighted with the outcome of my treatment by Pedro. Meticulous attention to detail explaining exactly how the procedure would be carried out from first consultation to completion backed up with supporting guidance notes. Clearly an expert in his field and someone who cares passionately about the outcomes for his patients. Highly recommended.
George Jones
I loved my first visit to Maida Smile Dental Clinic. The staff member at reception was very warm, welcoming and professional. My dentist, Priscilla, and her assistant were fantastic. I have quite sensitive teeth near my gums and I can find the probing and investigation quite uncomfortable during a consultation, but this wasn’t the case at all. I didn’t experience discomfort and felt in very safe hands. This also applied to the hygienist work. I didn’t even have to ask Priscilla to avoid using the ultra sound cleaner on the sensitive areas of my teeth. I’m looking forward to going back, and that’s not often you can say that about going to the dentist!
Simone Gibson
Since I first had the luck to be recommended and book an appointment with Dr. Pedro Gutierres over 8 years ago, I have never trusted my dental health nor my family’s to anyone else. It’s very hard to find a dentist who ticks all the boxes and even goes beyond any expectations you may have, from service, sympathy, professionalism, and expertise, etc., 5 stars are not enough to rate him. I was so happy when he opened his own clinic and surrounded himself with the best professionals you can find, I cannot recommend Maida Smiles Dental Clinic enough.
Sofia Gouveia
Maida Smiles Dental Clinic is excellent!! The staff is very friendly, professional and always aiming for the customers best experience! A special thank you to Dr. Pedro Gutierres who is truly amazing. I am absolutely satisfied with the results and highly recommend this great dental clinic!
Ana Cruz
Dr. Pedro Gutierres is the best Implantologist I have come across. His work is amazing and of very high quality! I would highly recommend him and Maida Smiles to all my friends and family. If you want the perfect smile this is the place to go.
Blossom
“Pedro was so patient and professional throughout my treatment for my implants.. I chose to have my treatment with a local anaesthetic rather than any sedation and have a very bad gag reflex when anything touches the back of my throat. His patience throughout the experience was wonderful, completely putting me at ease and he also gave me a technique to help me in the future. I have seen him for my follow up and fully intend to book an annual visit in 2020. which is no small thing as I live 60 miles away.I can thoroughly recommend him for any treatment.”
Denise Gilbert
I was very nervous to pull my ingrown wisdom tooth. Dr Pedro Guiterres made me feel really comfortable and the job was completed very professionally. It didn’t take long at all and I didn’t feel any pain. I would definitely recommend his service at this practice.
Jihan Daoud
From the day I made my first appointment. The team at Maida smile were amazing. They didn’t treat me like a customer but more like family. They have been great in every step in FINALLY GETTING MY DREAM SMILE from the receptionist to my dentist Pedro Laranjeira I can’t thank you enough and of course Pedro Laranjeira beautiful wife…… they are very professional and understand that I had to change my appointment now and then for work commitments and they were very understand. I will defo recommend them 100% not forgetting how chic the office is
Tracy Mensah
I was very nervous about having a dental implant but was immediately put at ease by Dr Pedro Gutierres. The procedure was explained in full and the care both during and after treatment has been of the highest standard. I received advice on how to look after my implant and have had no problems. I highly recommend.
Dawn Briggs
I had 7 implants installed by Dr Pedro Gutierres, including one which required a bone graft. In my 70 years I’ve had some bad experiences with dental treatment so it takes a lot for me to relax but, from my initial consultation, through to the end of the treatment, I had complete trust in Pedro’s expertise: preparations for the treatment and after-care were extremely thorough and fully explained, the treatment itself was surprisingly endurable (considering what was involved) and the implants have made a major difference to my life. If you are considering implants then I would whole-heartedly and sincerely recommend Pedro for this work.
Russ Hickman
I couldn’t recommend Maida Smiles enough: the care, attention to detail and the way Dentists and Nurses made sure I felt comfortable and safe throughout the treatments was incredible. Dr Pedro explained the treatments in detail to me and I have never felt under pressure to proceed… but I am very glad I did as I am happy and confident to smile again!
Mariana Pinheiro
Highly recommend this place to anybody looking for a friendly and trustworthy practice with an incredibly friendly and patient staff. Dr Pedro has been one of the best dentists I’ve ever had, he made me feel comfortable and were very knowledgeable in explaining every step of what he was doing and answering all of my questions. Amazing thorough the procedure, excellent communication, superb and professional treatment. I hope they keep it this way for a long time.
Joas Souza
Dr Pedro is a very good, confident and experienced professional. I’ve known him for some years now and always felt well cared for, either for small or bigger treatments.The facilities of the clinic are amazing and all the staff are very friendly. Highly recommended.”
Nelson Cafruni
I went to different clinics before, and nobody could really convince me until Maida Smiles did. The team here makes you comfortable , shows you different options and different budgets , and doesn't try to make you go only for one plan. I felt that the team was knowledgeable and wanted to help me , so that's why I decided to start
Diogo
I was referred to Dr. Pedro who did such a wonderful job with my teeth. The staff was extremely professional, they put you at ease, and it just made the whole experience easier. I've never looked back since
Theresa
"I told him, 'I want beautiful teeth, beautiful but natural, I don't want fake looking teeth.' Now I smile, I talk... it just makes you more confident. If you wear a beautiful nice suit... you have beautiful teeth, then it's like a perfect."
Louca
"I went to my hygienist a little while ago, and she said to me they were the best implants that she'd ever seen and she would never have known that they weren't my real teeth."
Sharon
Dr. Pedro explained the process of Invisalign to me. It sounded easy, it was quite a quick process, and the end result is my teeth moved back, so I'm quite happy.
Soula
I feel like I've not just developed a professional relationship with my dentist and the staff... they become more like friends as well, because of the kind of compassion and sympathy that they give you during treatment.
Alvin
"After a friend recommended the clinic, I was referred to Dr. Pedro, who did such a wonderful job with my teeth. The staff was extremely professional; they put you at ease, and it just made the whole experience easier. They have more than met my expectations. I have to have a few more implants, and I'm not afraid anymore. Now, finally, I can live again."
Lesley
"After not having a great experience with previous dental treatments, I was desperate for someone that I trusted. I broke a tooth, and even before I saw Dr. Pedro, he reassured me that I was going to be fine. He made me feel very comfortable and at ease. It was an amazing experience, from not only Dr. Pedro but also all the staff in the clinic, and I would definitely recommend [them] ".
Mariana
I chose Maida Smiles because of the reviews and a friend who was really happy with the results. The results definitely met my expectations. My expressions are much more smooth than before and it really makes the difference
Carolina
I’m very grateful for the quick and efficient service I received when I needed an emergency appointment. The staff were kind and accommodating, and the dentist provided clear, helpful advice that made a real difference. The whole experience was reassuring. Highly recommend their professionalism and expertise!
Safiya Guled
I am always anxious when having to see the dentist and this was one of my first experiences with Maida Smiles. The dentist, Benedict Harrison was very reassuring and immediately put me at ease. He was quite lucid in his explanations of what had to be done, etcetera, and is making good progress with the ongoing treatment. Also, the rest of the staff were friendly and just plain nice.
John Jacobs
Wow wow Dr Claudia is the best dentist in London, my kid adores her and it is always a pleasant visit. Can’t recommend her enough
Bel Cohn
I am delighted with the results of my replacement veneers.
Dr Benedict Harrison was very good at talking me through the whole process and keeping me informed during the treatment if there were any issues - which there weren’t.
He has a charming demeanour which is an added advantage in a dentist, who I think we all agree are not our favourite people, overall a 5 star experience.
Karen Shepherd
I went to the Maida Smiles Clinic for the first time and had the most wonderful experience! I am dentist phobic but strangely left the place with a big smile on my face (literally!). The receptionist was super kind, Susan was impeccable and very helpful, and I had my appointment with the most amazing dentist Dr Mafalda Vilhena. Couldn’t recommend her enough. She explains the whole procedure and is very rigorous in her work. Congratulations to Dr Pedro Gutierres for creating such an excellent working environment and to all the team. I will be back and bringing my family along and we don’t even live in Maida Vale. Thank you for such an impeccable job on my teeth and for taking my fear of dentists away. Note: they don’t cover NHS, only private bookings or with insurance.
Maria Monteiro
Address: 207-209 Sutherland Ave, London W9 1RU. Get directions.
Paid parking is available using ParkBee on Lanark Road (the road right next to the practice). For public transport users, we are a two-minute walk from Maida Vale tube station.
