Pathology of Periapical Periodontitis Flashcards
What is periapical periodontitis?
Inflammation of periodontal ligament and other tissues around tooth apex.
What are the causes of periapical periodontitis?
Usually due to spread of infection following death of the pulp
Extrusion of antiseptics through apex during root canal treatment
A high filling or biting suddenly on a hard object sometimes causes an acute, usually transient, periapical periodontitis
What tends to be the clinical findings associated with acute periapical periodontitis?
History of pulpitis
Escape of exudate into periodontal ligament causes a small amount of tooth extrusion
Pain well localised: Tender to touch/percussion
Tooth not vital & not responsive to vitality tests unless pulpal necrosis limited to single canal in multirooted tooth
As inflammation becomes more severe, there can be intense throbbing pain
Infection usually remains localised
Abscess can develop
Can spread in tissue planes causing facial swelling Rarely local lymphadenopathy
Very rarely, osteomyelitis or cellulitis
How would you manage acute periapical periodontitis?
Endodontic treatment
Extraction
Open drainage through skin or mouth if needed due to abscess causing swelling
What can you see radiologically & pathologically relating to acute periapical periodontitis?
Radiology: bone resorption not had time to happen so only radiographic change may be widening of periodontal ligament space
Pathology: acute inflammation i.e presence of neutrophils
What is the pathology of chronic periapical periodontitis like?
-Chronic inflammation and granulation tissue
What are the clinical signs relating to chronic periapical periodontitis?
- Low grade infection
- May follow acute periapical periodontitis
- Tooth is not vital, unless very rarely pulpal necrosis is limited to a single canal in a multi-rooted tooth.
- Symptoms may be minimal
-Can be tender to percussion
What are the radiological signs of chronic periapical periodontitis?
-Often diagnosed on identification of a periapical radiolucency
What are the sequelae of chronic periapical periodontitis?
Periapical granuloma and in some cases, subsequently radicular cyst
Acute exacerbation with suppuration/abscess, cellulitis and sinus formation
Very rarely, focal sclerosing osteitis
How do you treat chronic periapical periodontitis?
Extraction or root canal treatment
A radicular cyst may need to be enucleated (removal)
What are some features of periapical granulomas and how does it affect the tooth?
Most asymptomatic
May be history of pulpitis
But can have coexisting pulpitis and therefore be symptomatic
Tooth is not vital and will not be responsive to vitality tests unless the pulpal necrosis is limited to a single canal in a multirooted tooth
What are some radiographic features of periapical granulomas?
-75% of apical inflammatory lesions
-Most discovered on routine radiographs
-Tooth shows loss of apical lamina dura
-Bone resorption appearing as a radiolucency that may be circumscribed or ill-defined.
Size variable:
-Small barely perceptible to 2 cm
-Larger lesions may represent radicular cysts
-Can’t definitely distinguish from a radicular cyst on size alone
Root resorption can be seen rarely
What is important to remember about a periapical granuloma?
A periapical granuloma is NOT granulomatous inflammation so don’t get them confused!
What is the relation of periapical granulomas to apical scars?
It’s a defect created by periapical inflammatory lesions, may rarely heal by filling with dense fibrous tissue rather than normal bone
These fibrous periapical scars occur most frequently when both the facial and lingual cortical plates have been lost
What would you pathologically see regarding a periapical granuloma?
See chronically inflamed granulation tissue at apex of a nonvital tooth
Defensive reaction secondary to the presence of bacteria in the root canal with spread of related toxins into the apical zone
