Periodontal - Endodontic lesions and the periodontal abscess

• What is the definition of a combined periodontic-endodontic lesion?

  lesion where any coalescence of periodontic or endodontic lesions, irrespective of primary origin of lesion
• Periodontal tissues communicate with the dental pulp via:

  • The apical foramen
  • Dentinal tubules
  • Lateral root canals - additional blood vessels
  • Furcation root canals - additional blood vessels
  • Cracks and fracture lines
  • Perforation by dental instruments during RCT

  
• What is the relationship between periodontal inflammation and pulpal inflammation?

  
• What is periodontal disease with secondary endodontic involvement?

  • periodontal pocket extends to involve the apex or lateral canal causing loss of pulp vitality
  • a cause for pocket not resolving
  • Little evidence to suggest that this happens on a significant scale
  • Most likely only when the periodontal disease progresses to involve the apex of the root and involving the apical vessels traversing the apical foramen.

  
• What is primary endodontic with secondary periodontal involvement?

  A non-vital pulp causes an acute abscess which drains via the periodontal ligament forming a "pseudopocket" which may be relatively narrow. You may this is periodontal disease but its actually a non vital tooth

  
• Inflammation in the pulp system can be induced by...?

  • Restorative procedures e.g. exposure, thermal damage or chemical damage
  • Caries
  • Trauma
  • Dentine exposure
  • This can lead to pulp necrosis and subsequent infection leading to a non-vital pulp
• What is a combined periodontal - endodontic lesion?


  Both a periodontal pocket and endodontic lesion co-exist and progress to communicate with each otherWhich do I treat? The perio or endo disease?

  
• How do we diagnose a combined periodontal - endodontic lesion?

  *History of onset and development of signs and symptoms*Clinical examination*Special tests*Radiographs*Vitality tests
• How does the history taking help with diagnosis of a combined periodontal - endodontic lesion?

  • difficult to obtain clear history for chronic, symptomless, periodontal-pulpal lesions
  • Diagnosis easier during acute episode.
  • history of severe bouts of severe pain, keeping awake at night, stimulated violently by hot/cold/sweet may reveal a previous history of irreversible pulpitis. This may have been some time ago, however.
  • may allude to a non-vital tooth.
• When do primary endodontic lesions typically present?

  • heavily restored
  • marked surface loss with attrition, erosion and abrasion combined or in isolation
  • discoloured showing signs of previous trauma
  • Isolated deep pocket in one area, atypical of general level of periodontal destruction
  • Pocket often on the buccal / palatal surface and not interdentally as in established Chronic Periodontitis
  • root surface is free of sub-gingival deposits
  • No other periodontally involved teeth in the mouth.
• What is a typical primary endodontic finding with secondary periodontal involvement?

  
• What are signs of chronic periodontitis?

  • Pockets usually possess a wide orifice at the gingival margin
  • Deposits of calculus are present
  • Pockets tend to be deepest interdentally
  • Teeth are rarely affected in isolation
• What is a vitality test?

  • thermal, electronic and possibly tactile stimulus e.g. a bur
  • A non-vital tooth with an endodontic component responds negatively.
  • Beware of false positives and false negative responses.
• What is the response to cold and electronic pulp testing?

  For endodontic lesions will have no response, for periodontal lesions will have a normal response.

  
• What do we look for in radiographic examination?

  • signs of endodontic origin
  • Loss of lamina dura or widening of the periodontal membrane space
  • Apical or lateral areas of rarefaction i.e. "apical areas."
  • Furcation radiolucencies may be endodontic in origin
  • Deep fillings ,deep caries, pulp caps
  • Periodontal signs
  • Bone loss, calculus deposits
• How is periodontal disease with secondary endodontic involvement treated?

  • If the pocket has reached the apex of the tooth, the disease is very advanced and the tooth is often untreatable
  • Extraction may be the best option
• How is primary endodontic with secondary periodontal involvement treated?

  • diagnosed early and root canal therapy instituted, the lesion may heal rapidly
  • in this case there will have been little chance of secondary plaque accumulation of the "pseudopocket"
  • Conversely a longstanding lesion will develop the features of Chronic Periodontitis and success will depend upon successful RCT and RSD
• What is the periodontal component in the treatment of primary endodontic with secondary periodontal involvement?

  • Periodontal treatment may not be required if the duration of communication is short
  • Regeneration can be expected if plaque contamination of the root surface has not occurred
• How is the combined lesion treated?

  • Much more difficult to treat and diagnose
  • Not possible to determine what extent each of the combined aetiologies has contributed to the lesion
  • RCT should always be carried out first followed by periodontal treatment to cope with the residual pocket
  • Difficult to manage
  • Treatment success unpredictable

  
• What is the treatment sequence for a combined lesion?

  1. Root canal treatment
  2. Review after 2 - 3 months.
  3. If the lesion shows no signs of resolving perform appropriate periodontal therapy
  4. Review after 2 - 3 months after periodontal therapy and re-evaluate radiographically
• What is an abscess?

  a collection of pus within a pyogenic membrane can be acute or chronic - related to periodontal pocket
• What are some other types of abscesses?

  • Gingival - Previously healthy site, caused by foreign body impaction
  • Peri - coronal - Associated with an incompletely erupted tooth
• A periodontal abscess can occur when....

  • extension of infection from a periodontal pocket
  • follow physical damage to the periodontal tissues e.g. foreign body
• An abscess forms if ...

  there is obstruction to drainage A deep periodontal defect is very narrow and is easily blocked by tissue swelling, blood clot or calculus
• Where and when do abscesses typically occur?

  • In relation to pockets of bi/trifurcation - molars
  • deep and narrow and easily blocked
  • Incomplete removal of calculus/tissue debris from pocket results in incompletely healing, impeding drainage

  
• What are the initial signs and symptoms of abscesses?

  • Initial, deep throbbing pain
  • Tooth slightly loose and sensitive to touch
  • Overlying gingivae may be red, swollen and tender
  • Initially no fluctuation or discharge of pus
• What are extra - oral signs and symptoms of abscesses?

  • Infection spread into the surrounding tissues
  • cellulitis may occur
  • Swelling of the face, lip, lower eyelid
  • Lower tooth infection may in addition be associated with trismus and difficulty in swallowing
  • Associated lymphadenopathy
  • Malaise and increased temperature
• What are developing signs and symptoms of abscesses?

  • Pus discharge into the pocket
  • Pus may track through alveolar bone and form an abscess under the mucoperiosteum.
  • In this case the abscess is red, shiny, fluctuant and sensitive
• What are intra - oral signs and symptoms of abscesses?

  • Deep pocket
  • Pus discharge through pocket
  • Gingival swelling
  • Mobile tooth
  • Sinus if the abscess is an acute episode of an existing chronic abscess
  • Tooth tender to bite on
• What is the radiographic appearance of abscesses?

  • Evidence of crestal bone loss and periodontal disease
  • Late radiographic evidence may include bone loss at the side of the tooth especially in long standing abscesses
• What is the acute phase of treatment for an abscess?

  • Relief of pain
  • Drainage
  • Control the spread of infection
• How is an abscess drained?

  • Via the open pocket
  • Incision of a fluctuant swelling by the dentist
  • Advise on the use of Hot salt water mouthwashes (1/2 tsp salt to glass of hot water every 2 hours)
• How can the spread of infection be controlled?

  • Antibiotics to be given where systemic upset seen - temperature rise, Malaise, Patient feels unwell, Medically compromised
  • Amoxicillin 500mg tds 5/7
  • Metronidazole 400mg tds 5/7
• What is the chronic phase of treatment of abscesses?


  • Extraction?
  • Root surface debridement
  • Surgery
• What is differential diagnosis?

  the process of differentiating between two or more conditions that share similar signs or symptoms.