Root Canal Treatment is a procedure commonly performed to remove an inflamed or infected dental pulp from the tooth. This procedure will relieve the patient of dental pain and help preserve the function of the tooth.
A tooth with infected pulp will develop severe throbbing pain. If untreated, the pulp will become necrotic and the disease will spread to the tip of the tooth. The tooth will be tender to biting and tapping. Subsequently, a swelling will develop and form an abscess (Fig 1)
The patient is anaesthetized and the tooth is isolated under a rubber dam. This will ensure sterility of the operating site. The tooth is access from the top to expose the inflamed pulp. The pulp is removed using rotary instrumentation under the aid of surgical microscope (Fig 2).
The space created is disinfected with irrigants and sealed with gutta percha. Gutta percha is a rubber based material which is inert to the body. The access is sealed with a temporary filling or a permanent core build up (Fig 3). After the root canal treatment, the infection at the tip of the tooth will resolve and the bone will heal with time (Fig 4).
A previously root canal treated tooth may become symptomatic. Symptoms may appear as low grade pain, discharging pus or localized swelling. There are multiple causative factors for a failed root canal, such as recurrent caries, blocked canal or crown leakages (Fig 1). A Root canal retreatment can be performed to assist in the removal of the recurrent infection. A successful retreatment will help to prolong the use and the retention of a natural tooth.
Retreatment involves the re-engineering of the previous root canal treatment. The existing restoration and filling materials are removed (Fig 2). Recurrent infection within the canal space is treated with chemical disinfectants. The cleansed canal space is refilled and the crown reinstated (Fig 3). The infection at the tip of the tooth will begin to heal after the completion of the retreatment procedure (Fig 4).
Root end surgery or Apicoectomy is a micro-surgical treatment that aims at removing persistent infection at the tip of the infected root. This is an option when previous root canal treatment or retreatment has failed to eradicate the root canal infection (Fig 1).
A microsurgical opening is made at the tip of the infected root. The inflamed tissue as well as part of the root tip is surgically removed. The process is done under a surgical microscope and the use of microsurgical instruments. (Fig 2.)
The root end is cleansed and the space filled with a bio-compatible root end filling (Fig 3). The removal of infected tissues at the tip of the root will facilitate the healing of the bone (Fig 4).
Crack tooth is commonly associated with pain on biting on the tooth. A normal tooth consists of three layers, the enamel, the dentine and the pulp (Fig 1). The pulp consists of sensitive nerve endings. The tooth can be cracked by excessive forces placed on it. This can be attributed to eating hard food, grinding or clenching of the teeth. A crack that extends to the base of the crown can be treated with root canal treatment and a crown. A crack that extends to the root is deemed to have poor prognosis and may need to be extracted (Fig 2).
A forceful trauma to the teeth may result in the following:
1. Chipped/Fracture crown
2. Luxation (tooth is partially displace)
3. Avulsion (tooth is completely displace)
4. Root Fracture
After a trauma, the tooth may be chipped. This chipped may be confined to the enamel (outer layer of tooth), enamel-dentine (involving the second layer of tooth) or extend to the pulp (Fig 1). When the chipped is confine to the enamel/enamel dentine (Fig 2), the treatment may range from smoothening up the chipped surface to doing a filling or putting a crown on the tooth. However, when the fracture has extended to the pulp of the tooth, root canal treatment is indicated.
A tooth may be displaced partially from the socket after the trauma (Fig 1). It is carefully repositioned and splinted with a flexible wire. A root canal treatment is usually required if the tooth becomes non vital.
An avulsed tooth is a tooth that is completely displaced out of its socket (Fig 1). The avulsed tooth should be replanted into the socket within an hour. If the tooth cannot be replanted immediately, it should be stored in a suitable medium e.g. cold milk, and the child should be brought to the dentist as soon as possible. A tooth that is replanted within an hour has a better prognosis. The avulsed tooth will be splinted for stabilization (Fig 2). Root canal treatment must be instituted within 2 weeks for an avulsed tooth.
Trauma may result in root fracture. The tooth usually will be presented with a slight mobility. It will be tender to biting. Radiographs will be needed to identify the root fracture. The tooth with a root fracture needs to be stabilized with a splint. Root canal treatment may be required if the tooth becomes non vital.
Regenerative Endodontics provides alternative therapy in managing immature permanent teeth with pulpal necrosis with thin dentinal walls that have higher risk of cervical fracture. The protocol used for treatment is called regenerative endodontic procedures (REPs).
The aim of the treatment is to achieve complete restoration of pulpal function and subsequent completion of root development by replacing damaged dentin, root structures, and cells of the pulp-dentin complex. Case studies have shown healing of apical periodontitis, continued root apex development and increased thickness of the root canal wall in immature teeth with pulpal necrosis.
Clinical considerations for Regenerative Endodontic procedures include, young patient, necrotic pulp with immature apex. Minimal or no instrumentation of the dentinal walls, placement of an intracanal medicament, creation of a blood clot of protein scaffold in canal, effective coronal seal.
Regenerative endodontics involves a two- or multi-step procedure. First appointment focuses on disinfection of the pulp space. With absence of clinical signs and symptoms, the second appointment is centred on removing the medicament, release of growth factors by stimulating a blood clot, then sealing the tooth by placing a pulp space barrier such as MTA (mineral trioxide aggregate) and permanent coronal restoration.
Following completion of the regenerative endodontic procedure, close follow up appointments are important to ensure success of treatment. Guidelines for follow-up are 6-12 month evaluation for resolution of periapical radiolucency and increase in dentinal wall thickness. 12-24 month follow-up to monitor increased dentinal wall thickness and increased root length. During this follow up period if any pain, soft- tissue swelling or increase in size of radiolucency occurs, it indicates failure of the procedure and conventional root canal will be elected.