Following endodontic procedures, patients may sometimes experience pain no matter how carefully the treatment has been given. It would be prudent to warn every patient to expect a certain amount of discomfort following endodontic treatment, advising them that this is caused by an inflammatory response at the tooth apex. They should be advised to take over-the-counter analgesics, preferably NSAIDs. However, if the pain persists for more than two or three days, further treatment is probably required for one of the following reasons.
Recent restorations
Pain may be a result of: High filling
Microleakage Micro-exposure of the pulp Thermal or mechanical injury during cavity
preparation or an inadequate lining under metallic restorations
Chemical irritation from lining or filling materials
Electrical effect of dissimilar metals.
It is not always possible to know beforehand whether there is a pre-existing pulpal condition when operative procedures are undertaken. Consequently, a chronic pulpitis may be converted into an acute pulpitis.
Periodontal treatment
There is always a chance that some of the numerous lateral canals that communicate with the periodontal ligament are exposed when periodontal treatment is carried out. This aspect is considered in the section in Part 9 on perioendo lesions .
Exposure of the pulp
If a carious exposure is suspected, then removal of deep caries should be carried out under rubber dam. The decision to extirpate the pulp or carry out either a pulp capping or partial pulpotomy procedure depends on whether the pulp has been irreversibly damaged or not (see Part 9 calcium hydroxide). If there is insufficient time, or any difficulty is experienced with analgesia, temporary treatment, as recommended for irreversible pulpitis, may be carried out. Root or crown fractures
Most root or crown fractures can be avoided by adequately protecting the tooth during a course of root canal treatment. If the structure of the tooth is damaged between appointments, pain is likely to occur as a result of salivary and bacterial contamination of the root canal. If the tooth happens to fracture in a vertical plane, the prognosis is poor and the tooth may have to be extracted (Fig. 9). In the case of multirooted teeth, it may be possible to section the tooth and remove one of the roots.
Pain as a result of instrumentation
The two conditions that may require emergency treatment during a course of root canal treatment are:
acute apical periodontitis; Phoenix abscess.
Acute apical periodontitis may arise as a result of over instrumentation, extrusion of the canal contents through the apex, leaving the tooth in traumatic occlusion, or placing too much medicament in the pulp chamber as an interappointment dressing. Irrigation of the canal with sodium hypochlorite and careful drying with paper points is usually sufficient to alleviate the symptoms. The occlusion must be checked, as there is likely to be a certain amount of extrusion of the tooth from its socket. The term Phoenix abscess relates to the sudden exacerbation of a previously symptomless periradicular lesion. It can be one of the most troublesome conditions to deal with and occurs after initial instrumentation of a tooth with a pre-existing chronic periapical lesion (Fig. 10). The reasons for this phenomenon are not fully understood, but it is thought to be due to an alteration of the internal environment of the root canal space during instrumentation which activates the bacterial flora. Research has shown that the bacteriology of necrotic root canals is more complex than was previously thought, in particular the role played by anaerobic organisms. Treatment consists of irrigation, debridement of the root canal and establishing drainage. In severe cases, it may be necessary to prescribe an antibiotic.
Recent restorations
Pain may be a result of: High filling
Microleakage Micro-exposure of the pulp Thermal or mechanical injury during cavity
preparation or an inadequate lining under metallic restorations
Chemical irritation from lining or filling materials
Electrical effect of dissimilar metals.
It is not always possible to know beforehand whether there is a pre-existing pulpal condition when operative procedures are undertaken. Consequently, a chronic pulpitis may be converted into an acute pulpitis.
Periodontal treatment
There is always a chance that some of the numerous lateral canals that communicate with the periodontal ligament are exposed when periodontal treatment is carried out. This aspect is considered in the section in Part 9 on perioendo lesions .
Exposure of the pulp
If a carious exposure is suspected, then removal of deep caries should be carried out under rubber dam. The decision to extirpate the pulp or carry out either a pulp capping or partial pulpotomy procedure depends on whether the pulp has been irreversibly damaged or not (see Part 9 calcium hydroxide). If there is insufficient time, or any difficulty is experienced with analgesia, temporary treatment, as recommended for irreversible pulpitis, may be carried out. Root or crown fractures
Most root or crown fractures can be avoided by adequately protecting the tooth during a course of root canal treatment. If the structure of the tooth is damaged between appointments, pain is likely to occur as a result of salivary and bacterial contamination of the root canal. If the tooth happens to fracture in a vertical plane, the prognosis is poor and the tooth may have to be extracted (Fig. 9). In the case of multirooted teeth, it may be possible to section the tooth and remove one of the roots.
Pain as a result of instrumentation
The two conditions that may require emergency treatment during a course of root canal treatment are:
acute apical periodontitis; Phoenix abscess.
Acute apical periodontitis may arise as a result of over instrumentation, extrusion of the canal contents through the apex, leaving the tooth in traumatic occlusion, or placing too much medicament in the pulp chamber as an interappointment dressing. Irrigation of the canal with sodium hypochlorite and careful drying with paper points is usually sufficient to alleviate the symptoms. The occlusion must be checked, as there is likely to be a certain amount of extrusion of the tooth from its socket. The term Phoenix abscess relates to the sudden exacerbation of a previously symptomless periradicular lesion. It can be one of the most troublesome conditions to deal with and occurs after initial instrumentation of a tooth with a pre-existing chronic periapical lesion (Fig. 10). The reasons for this phenomenon are not fully understood, but it is thought to be due to an alteration of the internal environment of the root canal space during instrumentation which activates the bacterial flora. Research has shown that the bacteriology of necrotic root canals is more complex than was previously thought, in particular the role played by anaerobic organisms. Treatment consists of irrigation, debridement of the root canal and establishing drainage. In severe cases, it may be necessary to prescribe an antibiotic.