Defining the Periapical Condition
Part two of the Endodontic Diagnosis series.
A few weeks ago I had written a blog titled “Defining the Pulp Condition.” It was the first of a two part series reviewing the endodontic diagnostic terminology. The reason I wanted to review these definitions is because I feel that often the focus of endodontics is on the treatment itself and all the cool instruments, technology and toys we have. We focus on how nice an x-ray looks and the curvatures of canals. But before all of that, diagnosis remains king. And it is important to be able to communicate amongst dental professionals using specific diagnostic terminology. The comparison I had used in the first blog was that it is so common for us to talk of the classifications of dental caries or tooth mobility. We should be equally as comfortable with endodontic classifications. But my sense is that the endodontic definitions are not as standard or not as commonly used. Maybe we can help change that.
As mentioned before not only should we have a standard set of terms to talk amongst or colleagues, but I find it to be helpful when I record this information in the patient record. I can reference that when a patient returns for treatment or for future recall exam.
Unlike the pulpal conditions you will find that the Periapical (periradicular) definitions of diagnosis are not as straight forward and will require more time and use of the terms to be totally comfortable. With repeated use these terms will become ordinary. You may already know this information, but for those interested…read on. Perhaps even copy and paste this onto your computer desk top. Or refer back to both parts of this blog series when you have a chance at our website or Facebook page.
These definitions are taken from the American Association of Endodontics glossary.
Normal Periradicular Tissues. Normal periradicular tissues will be non-sensitive to percussion and palpation testing. Radiographically, periradicular tissues are normal with an intact lamina dura and a uniform periodontal ligament (PDL) space.
Acute periradicular periodontitis. Acute periradicular periodontitis occurs when pulpal disease extends into the surrounding periradicular tissues and causes inflammation. However, acute periradicular periodontitis may also occur as the result of occlusal traumatism. The patient will generally complain of discomfort to biting or chewing. Sensitivity to percussion is a hallmark diagnostic test result of acute periradicular periodontitis. Palpation testing may or may not produce a sensitive response. The PDL space may appear normal, widened, or there may be a distinct radiolucency.
Acute periradicular abscess. In this situation, bacteria have progressed into the periradicular tissues and the patient’s immune response cannot defend against the invasion. It is characterized by rapid onset, spontaneous pain, pus formation, and often swelling of the associated tissues. Depending upon the location of the apices of the tooth and muscle attachments, a swelling will usually develop in the buccal vestibule, on the lingual/palatal, or as a fascial space infection. Percussion testing produces a response that is usually exquisitely sensitive. This exaggerated response can help differentiate between acute periradicular periodontitis and the early stages of acute periradicular abscess. Palpation testing produces a sensitive response. Radiographically, the PDL space may be normal, slightly widened, or demonstrate a distinct radiolucency. This periradicular pathosis can occur with a necrotic pulp or a pulpless tooth that has been partially or definitely endodontically treated if continued bacterial contamination and/or leakage occurs.
Chronic periradicular periodontitis. When bacteria or bacterial products from a necrotic pulp or pulpless tooth slowly ingress into the periradicular tissues, the patient’s immune system may become involved in a chronic conflict. The resultant inflammatory process causes periradicular bone resorption that manifests as a periradicular radiolucency on the radiograph. Clinically, the patient is asymptomatic. Percussion and palpation testing produce non-sensitive responses.
Subacute periradicular periodontitis (chronic periradicular periodontitis with symptoms). The patient will present with mild to moderate symptoms that may include spontaneous pain or discomfort on biting or chewing. The tooth may present with any pulpal diagnosis. Percussion testing produces a mild sensitive response and palpation testing may or may not be sensitive. Clinical symptoms are not as severe as acute periradicular periodontitis. Radiographically, the tooth will present anywhere from a normal periradicular appearance to a distinct radiolucency. These patients must receive endodontic treatment in a timely manner because the condition can quickly progress into acute periradicular periodontitis or an acute periradicular abscess.
Chronic periradicular abscess (suppurative periradicular periodontitis). An inflammatory reaction to pulpal infection and necrosis characterized by gradual onset, little or no discomfort and intermittent discharge of pus through an associated sinus tract. Clinically, the patient is usually asymptomatic because the sinus tract allows drainage of any exudate from the periradicular tissues. EPT and thermal testing are non-responsive. Percussion and palpation testing usually produce non-sensitive responses. Radiographically, a periradicular lesion is associated with the involved tooth. This entity can also occur with a pulpless tooth that has been partially or definitely endodontically treated if continued bacterial contamination and/or leakage occurs.
Focal sclerosing osteomyelitis (condensing osteitis). This entity may be considered a true lesion of endodontic origin (LEO). The involved tooth will have an etiologic factor for low-grade, chronic inflammation such as a necrotic pulp, extensive restorative history or a crack. The patient may be asymptomatic or demonstrate a wide range of pulpal symptoms. EPT and thermal tests may or may not be responsive. Percussion and palpation testing may or may not be sensitive. Radiographically, the involved tooth will present with increased radiodensity and opacity around one or more of the roots. Evidence supporting consideration as a LEO is that 85% of these periradicular radiodensities resolve after endodontic therapy if they have a pulpal diagnosis of irreversible pulpitis.11
Focal osteopetrosis (periapical osteosclerosis). This entity is not a LEO. The patient will be asymptomatic. EPT and thermal testing are responsive and normal. Percussion and palpation testing will typically be non-sensitive. The involved tooth is usually a virgin tooth or has a normal pulp. Radiographically, the tooth will present with increased radiodensity and opacity around one or more of the roots. No treatment is necessary and the tooth should simply be monitored at periodic recall.8
Hopefully that was not overwhelming. It can be, and if you feel that way, just give it time and repetition. For me, I was able to feel more comfortable with these terms and definitions when I sat down to write reports to our referral offices. We include both the pulpal and periradicular diagnosis in our reports. As I think about the symptoms, the testing results, the radiographic and clinical signs I can picture the condition fitting just one of the terms above. Thus it was actively considering the tooth presentation and then physically writing/typing the information at the same time. Of course I guess I also have the benefit of seeing these conditions so frequently given the type of office in which we work.
**On a side note, I am considering many new topics for future blogs. But I am always open to hearing suggestions you would like to read about. Find us on Facebook at Tri City and Fallbrook Micro Endodontics and let us know your thoughts, comments, and suggestions.**