Question by mosmos

My teeth are slightly yellowish since young. I do not smoke or drink alcohol. I had tried many types of teeth whitening paste or toothpaste bought from the pharmacy and it does not helps in whitening the teeth. I am wondering what other teeth whitening methods I can go for.

Answered by Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

You may wish to consider seeking professional help from the dentist to determine whether you are suitable for teeth whitening procedures.

There are several teeth whitening methods that your dentist can prescribe. Tooth bleaching in the dental clinic, also known as in-office bleaching, is carried out using high concentrations of the peroxide bleaching gel.

The most popular tooth bleaching method is the home bleaching regime carried out by the patient under the supervision of the dentist.

The patient wears a custom-fitting bleaching tray filled with the bleaching gel and bleaching is carried out either in the daytime or overnight. The dentist will review the treatment progress periodically to ensure optimal progress.​​​

Home bleaching method is usually less expensive than in-office bleaching methods and are equally effective. If you are suitable for the teeth whitening procedure, your dentsit can recommend the appropriate method that best meets your needs.

Question by candy chua

I have 1 crooked front tooth and 1 sharp tooth (like vampire tooth) is more yellowish then the rest, Dentist said the front crooked tooth maybe dead but never mention about the others. I would like advice as in if i should do implant for only the 2 nos of crooked teeth or bridging? What is the procedure for these two options? How much does it cost for both checking and action?

Answered by Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

First, the dentist needs to assess the cause for the crooked and sharp looking teeth and whether they have​ become non-vital (ie; dead).

Root canal treatment can be carried out to remove the infected pulp tissue in a non-vital tooth and it can still remain functional in the mouth. It is not absolutely necessary to extract a non-vital tooth unless the tooth is badly broken down. An initial assessment by the dentist will help to determine the cause of and the treatment required for your dental condition. The dentist will likely take an x-ray to assess the root condition of your teeth.

Question by chongna

Hi Dr Sim, I'm 13 years old and am considering wearing braces to straighten out my teeth which are far apart. I've been advised to wait till I turn 16 which will be when my growth spurt is over, or else there is a risk that I might have to go through the painful and expensive treatment again. So is it advisable for me to start wearing braces now or after I turn 16? Thank you.

Answered by Dr Chew Ming Tak Senior Consultant Department of Orthodontics National Dental Centre of Singapore

Generally, braces can be started at 13 yrs of age if all permanent teeth have erupted and the dental problem is not associated with disharmony of the upper and lower jaws. If there is a problem with the jaws, the advice would be to commence treatment only when growth has pretty much stopped, usually at age 16 to 18 years. The orthodontist would be able to advise whether your teeth problem is associated with disharmony of the jaws.

Question by playst

Is teeth whitening a permanent or temporary solution to whiten our teeth? Can you recommend me a permanent teeth whitening solution (if it exist) and how much does the proceedure cost?

Answered by Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

In general, teeth naturally darkens over time from the foods and drinks we consumed, smoking, inadequate cleaning of teeth, physiologic aging, trauma, dental decay or genetic factors.

This process of darkening occurs naturally after the first whitening treatment, depending on what food and beverage you consume and how you maintain your oral hygiene. The rate of discoloration varies among individuals. There is no permanent teeth whitening solution.

Question by Shock Hwa

Hi, Is it true that all teeth whitening kit corrodes the enamel coating and weaken the teeth?

Answered by ​Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

The contents of different teeth whitening kits vary. Those present in over-the-counter whitening products may be more varied.

Generally the concentration of the bleaching agents or the acidity of the contents in these over-the-counter whitening products is not specified, while all professional tooth whitening kits have to specify and list down all the ingredients and the concentration of the active peroxide present.

Acidity can cause erosion of tooth structure and if one’s teeth have existing exposed dentine surfaces, these dentine surfaces can erode away very easily as they are softer than enamel. Tooth sensitivity can also be experienced. It is advisable to use products that are recommended by your dentist.

Question by Mak Soh Kuen

Hi

I have always wanted to straighten my 'bugs bunny' teeth. Is there any way to do it without extracting some teeth?

thank you

Answered by Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

We need to assess the cause of your 'bugs bunny' teeth before deciding whether they can be straighten without extracting some teeth.

In cases where there is overcrowding of teeth, it may be advisable to extract some teeth to provide space for better alignment of the remaining teeth. An orthodontist will be able to provide advice on this, based on your condition.

Question by albertlaw

1. My two front teeth was crowned more than 10 years ago,recently they become shaky and the cements on the edges can be seen clearly.Although there is no pain at the moment,is it necessary to remove the teeth and check for decay and to cement them back if they are found to be still useable?


2. I've a missing molar tooth.Although it does not affect me aesthetically as the tooth is hidden from view when I smile,but will it affect adjoining teeth and the gums in the long run?


3. ​I would like to know the differences between traditional implants and mini-implants in terms of costs,durability and any other advantages and disadvantages of these two kinds of implants.

Answered by Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

1. As your teeth have become shaky, it is advisable to seek a dentist's assessment of your dental condition to determine the cause of the tooth mobility. When a tooth has loss of gum support, it may become mobile. It is possible for a mobile tooth not to experience any pain. Generally, crowns or tooth decay do not cause tooth mobility.


2. A missing molar tooth may not be noticeable when you smile. In general, when a tooth is missing, the residual bony ridge slowly resorbs. The adjacent teeth may drift and tilt into the ‘missing molar’ space, while the opposing molar may gradually supraerupt, affecting the way you eat. Furthermore, the loss of a molar tooth can affect your chewing efficiency.


3. The rationale, methods and techniques of conventional or traditional implants have been well researched upon. The durability, its clinical use and functions have also been well documented.

Several long-term studies on the clinical effectiveness of these implants have been carried out and its success rate have been shown to be very good. Scientific r​esearch on mini-implants however, is very limited and at present, there is little scientific data to support the use of mini-implants as an alternative to conventional implants to permanently replace missing teeth.

​Question by fwy​

Dear Dr Sim, I drink milo or tea occasionally. Does these drinks contributes to the slightly yellowish stain that appears on the surface on my teeth and if I am a regular drinker of tea, should I still consider doing teeth whitening?

Answered by Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

All coloured foods and drinks can cause tooth discolouration, resulting in the teeth becoming darker with time. It is not practical to stop eating or drinking coloured foods and drinks permanently.

Furthermore, other factors such as smoking, poor oral hygiene, physiologic aging, trauma and dental decay can cause teeth to darken with time. Hence, teeth whitening procedures cannot be permanent solutions.

You can still proceed with teeth whitening if you understand that this process of the darkening of teeth will continue to occur naturally even your have undergone the teeth whitening procedure.

You can slow down the process of darkening by maintaining good oral hygiene and reducing the intake of coloured foods and drinks.

Question by cheese

My 2-year-old grandson has black stained teeth (just front few teeth only). He was on partial breastmilk and formula feed, and did not take sweet things, except Heinz fruit juice at times.

He was brought to a dentist when he was 1-year-old but as he refused/too scare to cooperate, the dentist just managed to glance at his condition and commented that it could be some bacteria which should not be too concerned as the baby teeth will drop off and adult ones will replace.

What is your comment? Should we bring him to dentist again or later?

Answered by ​Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

Your grandson is likely to have some chromogenic bacteria present on his primary teeth which causes the black stains.

As the primary teeth gives way to the permanent dentition, this chromogenic bacteria will go away as the permanent dentition is usually less affected by the bacteria. You could bring your grandson to the pediatric dentist for a thorough assessment.

Question by Mdm Ng Yuet Mei

Hi, my daughter who is 13 years old has protruding lower jaw. May I know what are the ways to correct it and is bracing necessary?And if bracing is one of the corrective method for protruding lower jaw, at what age should I send her for bracing? Thanks

Answered by Dr Chew Ming Tak Senior Consultant Department of Orthodontics National Dental Centre of Singapore

Generally, braces cannot correct the problems associated with a protruding lower jaw. Jaw surgery (Orthognathic surgery) is required. However, in cases where the protrusion of the lower jaw is not severe, braces alone can still be done to produce a satisfactory outcome. Braces treatment should be done after growth has pretty much stopped, usually at age 16 to 18 years.

Question by Miss Ho

Dear Dr Christina Sim,

I have heard about invisalign but know little about it. Can it replace the tradition method of wearing barces? What are the pros and cons of them?

Many thanks.

Answered by ​Dr Chew Ming Tak Senior Consultant Department of Orthodontics National Dental Centre of Singapore

Invisalign is a way of straightening teeth using invisible aligners which can be removed when eating or brushing. However, it is not suitable for severely crowded and mal-aligned teeth and as such, most patients would still need to have the traditional metal or ceramic braces (refer to HealthXchange website to find out more about pros and cons of the different types of braces).

Extraction is frequently required as part of the braces treatment. This is especially so in cases where there is over-crowding of teeth.

Question by rachel

I love drinking coffee and tea and must have a cup of each everyday. As a exult, my teeth are rather stained brownish at the edges and brushing just isn't good enough. What's the best thing I should do everyday to reduce the stains? Should I rinse mu mouth immediately afte each cup of coffee or not? I read somewhere that one should not brush our teeth fir a least 30 minutes after drinking wine or carbonated drinks. Does this apply to coffee and tea as well? As for the teeth whitening options, is it safe to use those from the supermarkets / pharmacy? what's the difference between those and the ones by a professional dentist? Thanks

​Answered by Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

Yes, rinsing your mouth after drinking the coffee helps to dilute the coffee left remaining in the mouth. In general, wait for 30 minutes before brushing your teeth after every meal.

The concentration of the bleaching gel in over-the-counter teeth whitening products is definitely much lower that in the in-office kits available from the dental clinics. Furthermore, the bleaching trays in these products are designed as one-size-fits-all unlike the customized trays that you will get from your dentist.

The downside of these one-size-fits-all bleaching trays is that not all surfaces of your teeth will be in contact with the bleaching gel and the gel may even contact your gum tissue instead. This can cause both tooth and gum sensitivity and for some patients, could be quite severe, resulting in ulceration.

Question by greenbamboo

Hi, my upper front teeth and incisors are turning orange color below the gumline. Could it be tartar? It is hard. I don't feel any pain, however I realise they are shrinking. The tartar seem to be eating up my teeth and I am afraid at this rate, they will become soft and drop out. How do I fix this problem? Many thanks!

Answered by Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

It is possible that your upper front teeth are showing signs of early tooth decay.

If so, these teeth need to be assessed whether the caries lesions have become cavitated. Non-cavitated lesions may be remineralized while cavitated lesions require restorations.

However, it is also possible that you have tartar buildup which had become stained. It is advisable to have a dental assessment to identify the cause of your problem to ensure that the appropriate treatment is rendered.

Question by Totoro Quek

Dear Specialists,

This morning I've read from Yahoo news about the Braces. My son who is 11 years old has approached me since last year that he would like to do braces due to the misaligned teeth.

May I kindly check with you what will be the suitable age for a person to go for braces ? Also, is there any recommendations for kind of braces for a kid to make for him without discomfort in wearing it?

Thank you and look forward for your reply. Gre​​atly appreciate it.

Answered by Dr Chew Ming Tak Senior Consultant Department of Orthodontics National Dental Centre of Singapore

Generally, braces treatment can start once all permanent teeth have erupted. This is usually at the age of 12-14 years. Conventional metal braces is recommended for children as these are still the most durable and effective option in treating badly misaligned teeth.

Hi Dr Sim, I wear a partial top denture but have my own teeth below. My teeth are not only crooked but also misaligned. When I had my last routine visit to the dental clinic at the Polyclinic, I asked the dentist whether I could straighten my lower teeth so that I can have a better bite on my food and improve my smile, she declined to discuss about it. My questions are: Is it because feasible for someone over 65 years old to realign teeth and wear braces? How costly is it, if there is no gov't subsidy? Thank you. ACGT

Answered by​ ​Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore​

An orthodontist will need to assess whether your teeth are healthy and suitable to go through the straightening process (orthodontic treatment). The teeth should still have good gum support and good gum health.

In general, it takes a longer time to straighten adult teeth as compared to those of children and teenagers. It is also useful to have your dentist examine your denture to assess whether it is still fitting well; as a loose or ill-fitting denture will compromise your chewing efficiency. You may wish to explore other tooth replacement options such as a bridge or implants and whether these options are viable for you.

Question by ​[email protected]

How do you correct a gap between your upper 2 front teeth? What procedures would a good dentist advise his/her customer?

Answered by Dr Christina Sim Senior Consultant Prosthodontic Unit, Department of Restorative Dentistry National Dental Centre of Singapore

It depends on the width of the gap. If the gap is narrow, it may be 'closed' by re-contouring the 2 front teeth with restorative material.

This will however, make the 2 front teeth look larger. Hence, if the gap is too wide, the restored teeth will look disproportionate in size and shape with regards to the adjacent teeth. Alternatively, the gap may be closed by orthodontic movement, which will bring the 2 front teeth together.

Ref: T12