MS2 - Interdisciplinary perio 2 - Endo-perio

Question 1

Learning outcomes

Answer 1

• understand he etiological process involved in Endo-Perio lesions
• Describe the process of clinical case assessment in suspected Endo-perio cases
• describe the sequence and rationale for the treatment in cases with endo-perio lesions

Question 2

What are some pathways on communication between the dental pulp and periapical tissues? (3)

Answer 2

• apical foramen
• accessory canal / lateral canals/ramifications
• dentinal tubules

Question 3

(extra)

What role does cementum play in protecting against bacteria invading dentinal, which areas can bacteria penetrate through and what may be an iatrogenic cause of this?

Answer 3

• Cementum is a continuous calcified structure and can protect against the the penetration of bacteria into the tooth’s root
• where the cementum is thin or even lost, the bacteria may be able to penetrate through the dentinal tubules
• root planing causes loss of cementum to become very thin/lost

Question 4

(extra)

What is root planing and why is debridement typically done instead

Answer 4

root planing is removing plaque and calculus as well as the affected cementum, whereas debridement is removing the plaque and calculus and allowing the cementum to re-calcify

-cementum will not regenerate by itself, and even with GTR, is one of the hardest structures to regenerate

Question 5

Types of endo-perio lesions (Prior to 2017 classification)

Answer 5

A. primary endo lesion - retrograde periodontitis

B. primary perio lesion

C. primary endo lesion with primary periodontal lesions

D. combined lesion

(first 3 arent rly endo-perio lesions in the true sense)

Question 6

What anatomical entities may cause endo-perio lesions? (6)

Answer 6

• lingual grooves
• root/tooth fractures
• root anomalies
• intermediate bifurcation ridges
• cervical enamel projections
• trauma-induced root resorption

Question 7

Briefly demonstrate the 3 general types of endo-perio lesions

Answer 7

Question 8

How do you classify Endo-Perio lesions

(according to the 2017 classification)

Answer 8

Question 9

Helpful flowchart

Answer 9

Question 10

What is the prognosis of teeth with endo perio lesions (EPLs) and the factors that would cause these? (2)

Answer 10

Hopeless: EPLs associated with trauma or iatrogenic factors (eg. perforation)

Poor or Favourable: EPLs associated with Endodontic and Periodontal lesions, and depends on the extent of perio involvement and whether endo will have an adequate seal

Question 11

How does a vital but significantly inflamed pulp affect the periodontium vs how a necrotic pulp would affect the periodontium?

Answer 11

Vital → Little to no effect - as long as the pulp remains vital, even if there is significant inflammation

Necrotic pulp - results in bone resorption at the apex or along the root and apical radiolucencies (or in furcation initially)

Question 12

What endodontic procedures can affect the periodontium? (3)*

Answer 12

• Pulp extirpation
• Cleaning and shaping (eg. debris pushed into PDL, overextension of files or GP, perforation of floor of pulp chamber)
• Vertical root fracture during obturation or post placement

(basically everything)

Question 13

How can periodontal procedures affect the pulp? (2)*

Answer 13

• deep curettage damaging apical vessels (not common, but if severe bone loss and local bone defect present)
• Scaling and debridement removing cementum, leading to open dentinal tubules / lateral canals

Question 14

What is a Primary endodontic lesion, how may it cause a localised deep pocket, what may you see radiographically and is it usually associated with generalised perio?

Answer 14

Necrotic pulp w chronic apical perio and sometimes draining sinus tract → drains through PDL or gingival sulcus

-radiograph reveals an isolated periodontal problem around an individual tooth

there is usually no associated generalised perio

(essentially just pulpal lesions, not true endo-perio in that sense)

Question 15

How can you investigate to confirm a primary endodontic lesion?

Answer 15

• Negative pulp vitality testing
• tracing sinus tract reveals origin at apex (may only go to mid root if lateral ramification involved)

Question 16

If confirmed to be a primary endodontic lesion, how should you treat, what is the prognosis and when would there typically be complete healing clinically and radiographically?

Answer 16

Treatment:

• RCT - sinus tract should heal after
• no root debridement required

Prognosis:

• Excellent prognosis, if RCT with good seal is possible. (rapid healing)
• complete clinical and radiographic healing in 3-6 months typically

Question 17

What is a primary periodontal lesion and how may it be confused with an endodontic lesion? If there is pain, what is likely to have happened?

How can you differentiate from an endodontic lesion?

Answer 17

• primary perio lesion is a periodontal issue due to attachment loss, fracture, anatomical variations, etc
• Primary perio lesions can sometimes mimic endo problems clinically and radiographically

Minimal/dull to no pain, if pain in present → possible coronal fracture that extends into the PDL

Clinical Tests

• Periodontal pocket may reach apex of involved tooth
• (Differential diagnosis) Pulp testing → within normal limits (vital) history taking - no pus etc from the area

Question 18

If confirmed to be a primary periodontal lesion, how should you treat and what is the prognosis?

Answer 18

Treatment:

• Periodontal therapy
• no RCT, unless pulp vitality changes
• Re-evaluation to assess for possible retrograde endodontic problems (infection from the apex)

Prognosis:

• entirely depends on the periodontal therapy (eg. graft, GTR)
• If attachment loss reached or was close to the apex, most teeth will become non-vital - not favourable prognosis

Question 19

What is a Primary endodontic lesion with Primary periodontal involvement?

How do you test for this?

Answer 19

Primary endo lesion with an independent perio lesion

Tests:

• Pulp vitality is negative
• Perio pockets present that do not extend to the periapical lesion

Question 20

How do you treat a Primary endo lesion with a primary perio lesion? what is the prognosis?

What is the prognosis if only RCT done?

Answer 20

Treatment:

• RCT - be conservative in tx
• periodontal therapy debridement is necessary

Prognosis:

• Endodontic component - excellent (if RCT goes well)
• Perio component - dependent upon the periodontal prognosis and tx
• If only RCT done → limited healing is expected as perio component not treated adequately

Question 21

What is a primary periodontal lesion with secondary endodontic involvement?

Typically, what are the symptoms? What can iatrogenically cause this?

Answer 21

When periodontal involvement extends to the apex of a tooth, retroinfection of the pulp can occur

Symptoms:

• Pts can sometimes experience severe pain, then cease having pain due to the apical vessels and nerves being affected
• pts may say they had a pain in the area ‘a few months ago’, etc

Can be iatrogenic cause from root debridement

Question 22

What is a primary periodontal lesion with secondary endodontic involvement?

Typically, what are the symptoms? What can iatrogenically cause this?

Answer 22

When periodontal involvement extends to the apex of a tooth, retroinfection of the pulp can occur

Symptoms:

• Pts can sometimes experience severe pain, then cease having pain due to tooth becoming necrotic (pts may say they had a pain in the area ‘a few months ago’, etc)
• infection can also follow through lateral canal

Can be iatrogenic cause from root debridement or dentinal abrasions (but rare and difficult to confirm)

Question 23

How can you test whether a lesion is primary perio secondary endo lesion?

what issue can occur when pulp testing?

Answer 23

Tests:

• the pt often has generalised perio (usually severe - stage III, IV grade C)
• Pulp testing: - results can sometimes be mixed (eg. molar with one vital canal, others necrotic - slow response) - when pulp inflamed, cold produces immediate response

Question 24

How would you treat a primary perio, secondary endo lesion? What is the prognosis?

Answer 24

Treatment:

• conservative RCT (first, if unsure abt it, dont progress to perio as pointless)
• Periodontal therapy in conjunction

Prognosis:

• Prognosis dependent on the periodontal therapy
• healing response of PA lesion (after RCT) is not predictable because of periodontal communication → favourable endodontic prognosis only obtained when tooth is in closed and protected environment

Question 25

What is a True Combined Endo-Perio lesion? What differential diagnosis must be included?

Answer 25

Lesion formed when pulpal and periodontal pathoses develop independently and unite

usually have signficant perio involvement

similar to secondary endo on pre-existing primary perio lesion

DDx must include vertical root fracture

(dont know which came first)

Question 26

How do you test whether and endo-perio lesion is a True Combined Lesion?

Answer 26

Tests:

• Pulp tests - negative
• tooth will have deep pockets at multiple sites
• radiographs by placing multiple GP or silver points into the sulcus and tracing them to the apex
• TTP: +ve?
• also need perio chart

Question 27

How would you treat a tooth with a True combined lesion and what is the prognosis?

Answer 27

Treatment:

• Periodontal therapy - can be initiated before, during or after tx (but endo is deciding factor so best to do first)
• Various periodontal and endodontic approaches can be taken, including: hemisection or root resection
• advanced endodontic surgical intervention may also be indicated

Prognosis:

• dependent on the perio therapy (after endo complete)
• the greater the perio involvement, the poorer the prognosis

Question 28

(Extra) Other clinical situations where you may need to remove part one root or half tooth (hemi-section, root resection)

Answer 28

• furcation involvement (hemisection)
• perforation
• fractured files
• Infection of one root, leading to localised bone loss

Question 29

Summary of pulpal and periodontal infection dx in endo-perio lesions

Question 30

Where traditional endo-perio tx prove insufficient, what are some alternative treatment modalities for maxillary molars and mandibular molars?

Answer 30

Maxillary molars - root resection/amputation of the affected root

Mandibular molars - hemisectioning is most commonly done

(hemi-section cant be done in mx as 3 rooted)

Question 31

If there is an endo-perio lesion present, do you do endo tx first or perio tx?

Answer 31

Always do endo first

• able to assess restorability and endo prognosis, and if it is poor, extraction is a better option to prevent more bone loss around the tooth
• wait atleast 6m before deciding to do surgical perio tx

Question 32

Is debridement alone adequate in treating perio-endo lesions which had perio involvement primarily / independently?

Answer 32

No, typically it’ll require periodontal surgery to treat the bony defects

Question 33

What is shown here given ONLY endo was done

Answer 33

primary endo

Question 34

If prognosis is questionable or poor even with good perio and endo tx, what is indicated and why?

Answer 34

exo to prevent further bone loss and future restorability of area