Let’s talk about teeth 

Looking after our teeth is important and should be a life-long commitment. Keeping healthy teeth will allow us to eat (function) and smile (aesthetic) confidently. Most head and neck cancers are treated with surgery or radiotherapy or, a combination of both. Chemotherapy is also considered, and increasingly used to enhance the effects of radiotherapy in some cases. 

Head and neck cancer treatment can affect the health of our teeth (oral health). Radiotherapy causes both immediate side-effects with our oral health, as well as long-term sequelae, which includes dry mouth, increased risks of dental caries (tooth decay), and osteoradionecrosis. Hence, for anyone who completed head and neck radiotherapy, it is essential to be proactive in preventive dental care. The following oral health preventive measures should not be overlooked: 

  1. Brushing your teeth with fluoride toothpaste 

Tooth brushing should be carried out morning and night using a fluoride containing toothpaste. As dry mouth is likely to continue to be a problem following radiotherapy, the use of high fluoride toothpaste will protect our teeth. Dentist would usually recommend the use of Colgate Neutraflour 5000 toothpaste. After brushing, try not to rinse out your mouth. If you can tolerate toothpaste around your mouth, please spit out only and leave the residual toothpaste around your teeth. The mechanism of fluoride action is to strengthen the enamel layer of our teeth, and prevent dental caries. 

  1. Recommendations for a dry mouth 

Keeping our mouth moist is vital for good oral health. A dry mouth can be uncomfortable when it comes to eating and talking. Aim to drink 6-8 glasses (or equivalent) of water per day. More importantly, try and maintain a moist mouth at all time. One can consider using sugar-free chewing gum or lozenges to stimulate the salivary glands. Alternatively the use of cooking oil with oral lubrication is a simple and effective way to help with dry mouth. A teaspoon of cooking oil or making up a “mouth spray” using a clean plastic spray bottle filled with water and cooking oil can be useful. It is also recommended to continue with the use of baking soda mouthrinse long-term. There are also specific products which are available to help your mouth feel less dry. Please discuss with your dentist about using the right products, for example GC Dry Mouth gel, Oral 7 Moisturising products, Xerostom Mouthspray etc. 

  1. Watch what you eat 

Avoid or minimise sweet and acidic foods. If not, eat sweet or sticky foods only around your main meal times (i.e. three times daily). Avoid snacking throughout the day. Acidic foods include wines, juices and many soda drinks (carbonated beverages). Every time we eat, our mouth becomes acidic. Teeth can dissolve in an acidic mouth. In normal circumstance, we depend on our saliva to neutralise the acidic environment in our mouth. This is achieved by 

the minerals present in our saliva through the dynamic process of remineralisation. In a dry mouth, where there is less saliva, the remineralisation process is reduced, which results in increase risks of dental caries. Hence, by watching what we eat and also the frequency of eating/snacking, this can help to minimise the risks of dental caries. Using fluoride containing toothpaste is vital. Consider rinsing your mouth with baking soda mouthrinse (especially after each meal) can reduce the acids and help prevent dental caries. 

  1. Regular dental visits 

It is important to visit your dentist regularly following radiotherapy. Advise your dentist you had completed head and neck radiotherapy. Your dentist will check your teeth and should implement a strict dental hygiene care plan and preventive programme including fluoride treatments. Frequent dental maintenance appointments in a timely manner are imperative. A 3-6 monthly dental check-up initially is recommended. Once oral health is maintained, the recall appointment can be extended. Do not wait until you have a problem with your teeth as the destruction of teeth can be rapid and difficult to control especially in a dry mouth. Moreover dentist can also screen for any new pathology or recurrence with your dental check-up. 

  1. Understand your risks of osteoradionecrosis 

Osteoradionecrosis (ORN) can be described as bone death. It is perhaps the most severe complication of radiotherapy. The process of ORN can be spontaneous or result from trauma. Trauma can be caused by poorly fitting dentures or an invasive dental procedure like dental extraction. Removal of teeth following radiotherapy put patients at risk of ORN and should be avoided if possible. It is important to have your teeth checked prior to starting radiotherapy, so any teeth with poor prognosis can be removed in a timely manner to avoid ORN. 

The risk of ORN does not diminish with time, and hence do not allow a dentist to extract a tooth following radiotherapy without consulting with your radiation oncologist. The radiation oncologist can advise on the radiation field and dose to your teeth specifically, which determine the risks of ORN. ORN is a painful and debilitating condition, and can be difficult to treat and manage. 

Head and neck radiotherapy may result in multiple unpleasant early or late side effects affecting our oral health. This can impact on general wellbeing and quality of life. Looking after our teeth following radiotherapy cannot be over emphasised and a proactive preventive oral hygiene plan is mandatory. Look after our teeth today. It is not too late to start now. 

Dr Guo Ling BDS, DClinDent (SND) Hospital Dental Surgeon | Auckland Regional Hospital and Specialist Dentistry