Q1 : What is root canal therapy?

Root canal therapy is the procedure involving removal of diseased pulp tissues, cleaning and filling the root canals with special dental tools and materials. The aim of endodontic treatment is to maintain the health of periapical tissue and keep the tooth in function. 

Q2 : When do you need root canal therapy?

Teeth are composed of the outer layers of hard structures (enamel and dentin) and the inner soft, living nerve tissue and blood vessels (pulp). Bacteria can go into the pulp through deep decay, tooth fracture, biting trauma, or gum disease. If it is the case, you usually feel pain and may require a root canal procedure to be done.

Q3 : What are the procedures of root canal therapy?

Local anesthesia

Numbing medicines will be given through injection into gum to help you lose pain.

Rubber Dam Application

A rubber sheet is put onto the diseased tooth to isolate it from salivary contamination.

Open chamber

Drilling will be done to reach the pulp for removal of necrotic and inflamed pulp tissues.

Cleaning and shaping

After the pulp is removed, the inside of the tooth is carefully cleaned and disinfected with delicate tools.

Root Canal Filling

After cleaning and shaping, the dentists will fill and seal the root canals with a rubber-like material called gutta-percha to prevent bacteria from re-entering.

Q4: How many dental visits will a course of root canal therapy need?

Front teeth ( incisors, canines )

A full treatment course for one front tooth usually needs two to three visits.

Back teeth (premolars, molars)

A full treatment course for one back tooth such as a molar may take four to five visits because molars have more root canals than incisors or canines.

Q5 : Why are X-ray exams necessary for root canal therapy?

During the treatment, repeated x-ray examinations will be required. Dentists basically depend on x-rays to identify the presence of lesions, measure the tooth length, and examine the structure of root canals. Since the radiation dose is low, please don’t worry about the radiation-related side effects.

Q6 : What will happen if you don't get root canal therapy for a deeply decayed tooth?

The symptom caused by an infected pulp varies. Some may feel pain, whereas some are asymptomatic. Asymptomatic cases may become chronic, unpredictable infections which can progress into terrible infections anytime.

Q7 : Why a dental prosthesis is needed after root canal therapy?

The tooth usually requires a prosthetic crown ( a metal/ceramic cap ) to rebuild the tooth’s shape and protect the tooth from further breaking down. When the decay is large, an additional metal pin which is called “post” will be put into the root canal to hold the crown.

Without the prosthetic crown, the color of tooth will gradually turn dark after root canal therapy. For front teeth, it looks bad when smiling. The treated tooth is also prone to breaking down. For back teeth, fracture may happen because of the fragile tooth structure. A proper final dental prosthesis is important to salvage the tooth successfully.

Q8: What should you do during the course of root canal therapy?

1. Do not chew or bite hard food because the treated tooth is relatively weak.
2. You may feel slightly pain or get some vague, weird feelings for a while. It is common and basically normal. However, if you have terrible pain or a swollen face, please contact your dentist.
3. The medicament used in the root canal treatment is similar to bleach. Although it is isolated and protected by a treatment towel, it may still be splashed on the clothing. Therefore, please try to avoid wearing dark and expensive clothing during the treatment.

Q9 : Why is root canal therapy in need of dental operating microscope?

• The dental operating microscope provides enhanced lighting and visibility. It is particularly useful in identifying tooth cracks, finding calcified and additional canals, removing posts (metal pins) and broken instruments, and repairing perforations and performing periapical surgery.

Q10: How to treat permanent tooth with open apex?

• The treatment plan of open apex permanent tooth should be fully discussed with patient and patient’s family; the indication, contraindication, pros and cons of the treatment procedure should be well informed before dental management.  
• Apexogenesis, apexification or endodontic regenerative procedure may be performed under microscope.