The Periodontic UnitProsthodontic Unit, and Endodontic Unit, all three departments from the National Dental Centre Singapore (NDCS), answer common questions about oral health, hygiene and dental treatments. NDCS is a member of the SingHealth group.

9 FAQs about dental health and dental treatment

1. How much toothpaste should I use to ensure proper cleaning of my teeth?

A pea-sized amount is sufficient. Toothpaste contains a lot of abrasive chemicals that can cause unnecessary wear and sensitivity, so using too much is not good.

2. Is it hygienic to keep toothbrushes in the toilet?

It is fine to keep them in the toilet, so long as they are kept separated, clean and dry to avoid cross-contamination by bacteria.

3. Should we brush our teeth after waking up in the morning or after breakfast?

Either is fine, but if you brush your teeth after a meal, try to do it only 20 to 30 minutes later. This is because food reduces the pH level in the mouth. When the pH level drops, our oral environment becomes acidic and our teeth are more vulnerable to attack. 

Saliva in the mouth will gradually clear out the acid and lay down new calcium to repair patches of teeth that were dissolved during this 20- to 30-minute time frame. Thus, it is always advisable to allow the pH level to recover before you brush your teeth.

4. Some say rinsing your mouth a few times a day is important. Is that true?

Rinsing your mouth gets the food remnants out when brushing is inconvenient. if you are diligent about flossing and brushing twice a day using the right technique, you should not even need a mouthwash. 

However, if you have mouth sores or gum diseases such as gingivitis or periodontitis, a prescription mouthwash can help reduce bleeding and inflammation.

5. Is it possible to be allergic to commercial toothpaste?

Yes, possibly to flavours/fragrances in the toothpaste, such as c​innamal (flavouring from cinnamon) spearmint, peppermint, carvone (oils from caraway seeds) and anethole (flavouring from star anise, fennel and anise).

6. Can rubbing salt on teeth help prevent decay?

It used to be a traditional home-style alternative to using mouthwash at a time when dentistry was not advanced. But rubbing salt on teeth actually causes abrasions on the tooth surfaces.

7. Why do some people grind or clench their teeth when they are asleep? Is this harmful? How can it be prevented?

There is no proven cause of tooth grinding or clenching. However, they are often associated with stress, habitual tendencies or disturbed sleep cycles. Prolonged and intensive grinding or clenching of teeth can cause the teeth to break down – this can range from minor enamel chipping to vertical tooth fractures. It can also cause the masticatory (chewing) muscles to become tender and the jaw joints to wear down more quickly.

Suggested prevention strategies for tooth grinding include counselling sessions, massage therapy, and adopting regular sleeping patterns. To minimise the destructive effects of tooth grinding, wearing a night splint (dental appliance used at night) is often recommended.

8. Is it really necessary to see a dentist every six months? Why this interval? Why not just once a year, for example?

Dr Marianne Ong, Senior Consultant from the Periodontic Unit at NDCS shares, "This would depend on your medical and dental health. 

  • For people with good dental health, including those with well-controlled medical conditions such as heart disease and diabetes, I recommend they see a dentist every six months to a year. This is because brushing and flossing alone cannot get rid of plaque in harder- to-reach areas, such as the back of the molars or around tilted teeth.​
  • Healthy people with oral diseases such as caries (ca​vities) or gum disease due to poor oral hygiene, need to visit a dentist every three to six months. This is to ensure that oral diseases are nipped in the bud. When picked up early, caries and gingivitis (the early stage of gum disease) can be treated to minimise the consequences of leaving the disease to progress (for example, irreversible bone loss around the teeth), which can lead to more expensive dental treatment.
  • People with poorly controlled medical conditions such as diabetes, who also have poor dental health, should see their dentist once every two to four months. This is because patients with poorly controlled diabetes are more prone to developing periodontal disease, which may make it more difficult for them to control their blood sugar levels. This increases their risk of diabetic complications, such as kidney failure and retinopathy.
  • People with multiple medical conditions and who are taking multiple medicines (usually the elderly) should make a trip to the dental clinic once every two to four months as they are more prone to developing xerostomia (dry mouth). A reduction in saliva as a side effect of medication can lead to increased risk of dental caries.

In summary, the prevention of disease and the early treatment of identified disease are key to maintaining optimal oral health. Your dentist will advise you on the appropriate dental recall interval based on your current oral and general health."

9. Which is better in the long run: getting a root canal treatment or simply extracting the tooth?

Dr Lui Jeen Nee, Senior Consultant and Head of the Department of Restorative Dentistry at NDCS answers, "Root canal treatment is a viable alternative to tooth extraction and is the only way to save a tooth with irreversible pulp inflammation or infection. After a root canal procedure, the tooth is restored either with a filling or a crown. Choosing to retain your natural teeth, when possible, is always the best decision. But when there is inadequate tooth structure to support the restoration of the tooth due to extensive damage or decay, an extraction may be recommended instead."

Ref: I23 (ed)

Check out other articles on dental health:

Root Canal Treatment: How Painful Is It?

Wisdom Tooth: When to Extract

Gum Disease: Causes, Symptoms and Treatment

Am I Too Old for Braces?

Tips for Fresher Breath

How to Choose the Right Toothbrush