Dr. Barry Musikant
Pulpitis is inflammation of the pulpal tissues. Such inflammation may be reversible or irreversible. It may be symptomatic or asymptomatic. Assuming the pulpal tissue is still vital, the differentiation between a tooth that needs endodontic therapy and one that will not is most often determined by the use of thermal testing with some form of ice (endo-ice) being applied to the tooth.
Prior to applying the stimulus to the tooth in question, apply it first to teeth that are deemed normal, so one can get a baseline normal response. Please realize that normal testing will produce different results based on a patients age their individual threshold for sensitivity to pain. An 80 year old is less likely to respond to the application of cold on a normal tooth than a 20 year old.
After establishing the normal baseline, apply the cold stimulus to the tooth in question. The tooth in question should at least be limited to the right side or the left side of the face. Dental pain generally does not cross the midline. If after application there is a sharp response that disappears within a few seconds, the tooth is probably in a state of reversible pulpitis. This can happen when a new filling is placed or a restoration that is a bit to high is present. The treatment is generally limited to adjusting the bite. If the patient is having sensitivity when biting, but otherwise is responding normally to cold, note whether or not large fillings are present and then check with a bite stick (or tooth sleuth) to see if the pain is limited to function one particular cusp. This cusp may represent a thin shell of dentin and enamel that is breaking away from the crown of the tooth. When the crack expands under function it stimulates nerve endings in the dentinal tubules that produce pain under function. If this cusp is cleaved off without exposing the pulp, there is no need for contemplating root canal therapy.
If the response to cold lingers for more than a few seconds and the patient in addition states while no pain there is still a sense of “awareness” in the tooth, the pulp is in a state of irreversible pulpitis and requires root canal therapy. Unless the bite was high, as long as the inflammation is confined to the pulpal tissues there will be no pain to percussion or palpation. As the state of the pulp deteriorates, it can get to a stage where it is in a state of constant acute pulpal pain. At that point diagnosis is most clearly made by cold producing transient relief for the patient, as it contracts the gases that the degenerating pulp is producing within the enclosed space of the pulp chamber. Immediate intervention is required. This type of inflammation tends to rapidly extend to the periodontal ligament making the tooth exquisitely sensitive to percussion and perhaps palpation and also making the diagnosis that much easier.
There are those situations defined as asymptomatic irreversible pulpitis. The pulps are alive, do not react abnormally to thermal stimuli be it hot or cold, but still require treatment. This is a tricky situation. You don’t want to do unnecessary treatment. Yet, we don’t want to ignore a situation that may get worse. From my perspective, I would leave these situations alone and consider treatment only if a new restoration is to be placed or symptoms appear. At that point, I would take out all previous fillings and see if a pulpal exposure is evident. An exposure would call for treatment. If there is so little dentin left that a viable restoration requires the placement of a post, I would also proceed with treatment.
The next stage in the degradation of the pulp is full pulpal necrosis. There would be no response to heat or cold. One might think that a necrotic pulp would always display some symptoms, but unless the pulp is infected with bacteria, the pulp can die painlessly and stay that way for years. Given the high likelihood that bacteria will make their way eventually into the space occupied by the pulp, it is better to remove the dead tissue and seal if off from the potential of bacterial ingress. If and when bacteria do penetrate into the confines of a necrotic pulp, the situation will rapidly deteriorate to one of acute symptoms with swelling, pain, redness and perhaps fever. Immediate treatment is called for with supportive antibiotic thereapy.
The above discussion covers the states of pulpitis from normal to acute necrotic pulpitis. Beyond the stages of pulpitis are the various stages of periodontitis, inflammation of the attachment process holding the tooth within the bone. The most painful and easily diagnosed stage is acute apical periodontitis. The tooth is sensitive to percussion and palpation. Most often one will see a widened periodontal ligament attachment, its complete disappearance or the establishment of a well defined area of periapical bone loss. Again immediate intervention is called for.
The body has an immune system. As such, it can create a defense against the attack of bacteria that are launched from a necrotic pulp. This state of combat can create a chronic apical abscess where the expanding infection is limited by the body’s defense system and a balance is maintained where the patient is asymptomatic despite the clear evidence of periapical damage. The pain may be further alleviated by the presence of a fistula, an outlet from the source of the infection to the outside limiting the build up of infectious exudates that would otherwise lead to swelling and pain. In this situation, treatment is required knowing that at some point in time, the balance may be upset at the most inappropriate time, when a patient’s immune system is compromised for one reason or another. It is better to resolve these situations when the patient is healthier and the infection is chronic rather than acute.
There are other situations such as previously or partially endodontically treated teeth that may lead to acute or chronic periapical abscesses. These situations require not only a proper diagnosis, but a careful appraisal of just where the previous treatment came up short. Depending upon that diagnosis, the dentist will determine whether or not the tooth is salvageable and whether or not he/she should perform the procedure or send it to a specialist. Here a CBCT is quite useful in determining whether or not canals have been missed, any perforations occurred and possibly viewing the any major fractures that may be present.
The tools for diagnosis include:
1. X-rays from centered, mesial and distal inclinations
2. Hot and cold tests. Heat can be applied with hot liquids or gutta percha. Cold tests can be applied with sticks of ice or the use of Endo-ice.
3. Percussion tests, the end of a mirror handle.
5. Perio-probe to check for any pockets that are present
6. The tooth sleuth for checking occlusal fractures under restorations
7. Selective anesthesia for differentiating pain between teeth and quadrants. In this regard the use of intraligamentary intraosseous injections are most useful because they are the most selective.