Missing teeth

We have two sets of teeth. Primary dentition consists of 20 teeth and secondary or permanent dentition 32 teeth. The roots of primary teeth will usually dissolve or resorb between the age of 6 to 14, to allow these teeth to drop off and new teeth to come up.

I have encountered cases where the patients have congenitally missing teeth. The medical term for this condition is called 'hypodontia'. The common teeth that are missing in the permanent dentition are upper lateral incisors and lower second premolars. Sometimes their primary/deciduous teeth still remain in the jaws. The patient usually is not aware that the tooth has not been replaced by a permanent one, unless being told by his or her dentist during a routine check-up. I usually confirmed this occurence by taking a radiograph.

There are also cases where the patients complain of toothache due to large decay on these teeth. Sometimes, I perform a root canal treament, provided the root are not resorbed, in order to keep the tooth functioning in the oral cavity for as long as possible, especially for a young patient. However, the prognosis maybe be guarded. It is also possible that the retained primary tooth is fused to the jaw bone (ankylosed). I supposed one will just have to accept the fact that he or she is born with less teeth and ultimately, will need dental implants.

My Friday morning routine

I have been teaching dental students at the Dental Faculty, Universiti Kebangsaan Malaysia, for the past eight years. This is the place where students are trained to become one of us, the dentists.

I supervise them in the Restorative clinic. This clinic is in a large room with about twenty cubicles. Each cubicle has a dental chair. Dental treatment here is free and is open to public. A registered patient will be treated by dental students, who usually work in pairs. Most of the Year Four students are good and eager to learn. They remind me of my dental student's days. This is the time when you feel like a 'sponge' and you are required to absorb as much knowledge as your brain can take. Glad that this chapter of my life have ended. My duty is to guide them and check their work, step by step. I always tell my students that it is better to make a mistake here in dental school than when they are out on their own because they can learn from their mistake and I will be there to help and rectify it. That's the purpose of supervision.

Eight years is a long time. Perhaps, I should tell the Deputy Dean, who is a good friend of mine that it is time for me to close this chapter of my life too....

X-ray Vision

As a dentist, I sometimes wish I have X-ray vision so that I can see through those teeth and jaws...

Radiography is essential in dental practice. Radiographs are useful in detecting tooth decay during a routine dental check-up, especially decay under an old filling (secondary caries) and decay in between teeth (interproximal caries). It is better to detect interproximal cavities early to avoid a more complex and expensive dental treatment when decay becomes large. Some of these cavities are consealed and difficult to detect by just doing an intraoral examination. After explaining this to my patients, they usually agree to do the radiographic examination. Most dental procedures require taking radiographs. For each root canal treatment, at least three radiographs are required.

Many are concerned about ionizing radiation from the dental X-ray. X-ray machines nowadays are more sophisticated. I assure my patients that the radiation dosage is very low, which is 1-8 microSv for an intraoral radiograph (Bitewing/Periapical). We are exposed to more radiation from natural sources everyday, for example, cosmic ray, gamma radiation, foodstuff etc. To put you in perspective, the average annual dose of radiation from cosmic rays and gamma radiation are 300microSv and 400microSv, respectively.

X-ray facilites in private dental clinics are regulated by The Ministry of Health , with specific guidelines, for example, minimum size of the X-ray or treatment room and lead-lined walls of the room, to ensure safety radiation.

Give Root Canal Treatment a Second Chance.

It is not uncommon for a patient to refuse root canal treatment (RCT) when he or she needs one because of a past RCT that has failed and ended up losing the tooth. I am always disappointed to hear this.

I was taught in my Masters programme that RCT has 70-90% of favourable treatment outcome. Perhaps this patient is one of the few unlucky ones. I will not bore you with the long list of reasons that influence the outcome of RCT, but I just want to emphasize here that if the treatment is carried out under acceptable standard of care, it will usually solve the patient's painful experience due to the dental infection. If the tooth is still restorable, RCT is definitely the better option than removing it. Losing your teeth will also lead to a set of other dental problems later on.

So, to these people who refuse RCT, don't let that just one bad experience influences your decision, give RCT a second chance!

It is also possible to retreat or repeat the RCT on a tooth when the first RCT does not have a favourable outcome.