Endodontic periodontic lesion

Question 1

How does infec from the PDL to the pulp occur?

Answer 1

Pathogenic bac and inflam products of perio disease access canal/lateral walls/apical foramen = pulpal infec/necrosis (retrograde pulpitis)

Question 2

How does infec from the pulp to the PDL occur?

Answer 2

Pulpal disease
Procedural errors in RCT
Perforations
Vertical root fractures

= dentinal tubules, peri-radicular inflam

= bone loss and CAL +/- Pus discharge = retrograde periodontitis

Question 3

Endo-perio lesion classification?

Answer 3

Primary endodontic 2ndry periodontal lesion

OR primary periodontal 2ndry endodontic lesion

Both cause true - combined periodontal-endodontic lesions

Question 4

Primary endo secondary perio lesion?

Answer 4

Originally an endo lesion, infec spreads from apex and along the root to the gingiva
Pulpal infec can spread from accessory canals to the gingivae or furcation

Question 5

Primary perio 2ndry endo lesions?

Answer 5

Perio pocket can deepen to the apex and secondarily involve the pulp
Alternatively a perio pocket can infec the pup through a lateral canal

Question 6

True combined lesion?

Answer 6

2 independent lesions (periapical and periodontal) can coexist and eventually fuse with each other

Question 7

What classifications have been suggested to find the source of the infection?

Answer 7

Concurrent endodontic and periodontal disease without communication

Concurrent endodontic and periodontal disease with communication

Question 8

Why is knowing if lesions are communicating useful?

Answer 8

Non-communicating lesions suggest a true combined lesion with independent aetiology

Communicating lesions may be true combined lesions which have merged or lesions starting primarily as perio or endo and then spread to the other

Question 9

Why is knowing the original source of infection important?

Answer 9

It can implicate the management and prognosis of the case

Question 10

How to form a diagnosis?

Answer 10

History
Exam - endodontic, periodontal
Special tests - sensibility testing, radiographs

Question 11

What are the common clinical symptoms?

Answer 11

Mobility
Gingival swelling
Pus discharge
Pocket formation
Fistula tract
TTP

Question 12

What is involved in the endodontic exam?

Answer 12

Restorative status
TTP
Tenderness in sulcus
Swelling/sinus

Question 13

What is involved in the periodontal exam?

Answer 13

Probing around tooth )6 point)
Pus discharge from pocket
Mobility

Question 14

What are the special tests? Results for a perio-endo lesion?

Answer 14

Ethyl chloride
EPT
Tooth should be negative to both = non-vital

Question 15

What radiographs should be taken? Results for a perio-endo lesion?

Answer 15

PA = most appropriate
Vertical periodontal defect is often present
Radiolucency around the apex is present
A J shaped lesion may be present

OPT only indicates multiple sites needed for radiographs

CBCT when conventional radiography does not provide sufficient detail
e.g. 3D anatomy or suspicion of other causes e.g. resorption or perforation

Question 16

What other tests can be performed?

Answer 16

Tooth sleuth
Transillumination
= Rules out root fracture

Question 17

How to manage primary endo 2ndry perio lesion?

Answer 17

RCT
Review after 3 months
If no improvements in pocketing = non-surgical perio therapy
No improvement after another 3 months = surgery

Question 18

How to manage primary perio 2ndry endo?

Answer 18

RCT and perio therapy
Review after 3 months
If no improvements = surgical perio therapy

Question 19

How to manage true combined lesions?

Answer 19

RCT and perio therapy
3 month review - no improvement = further non-surgical perio therapy
3 months - no improvement - surgical perio

Question 20

Rationale for management of primary endo 2ndry perio lesion?

Answer 20

Primary endo 2ndry perio lesions have endodontic aetiology
Endo infec drains into the PDL
Perio lesion usually presents as a narrow defect
Endo tx usually resolves issue as it removes the infec source
Perio defect is often very narrow and not really conductive to instrumentation

Question 21

Rationale for management of primary perio 2ndry endo lesion?

Answer 21

Have a periodontal aetiology but the tooth has become non-vital = RCT
= Endo and perio therapy required

Question 22

Rationale for management of true combined lesions?

Answer 22

Have endo and perio aetiology
May or may not communicate
Endo and perio therapy indicated

Question 23

Alternative management options?

Answer 23

Place Calcium Hydroxide inside prepared canal rather than obturating whilst assessing the response to the perio therapy
Obturation is only undertaken once a response to the perio therapy is seen
HOWEVER no evidence to suggest this is better

Surgical intervention may be indicated earlier e.g. with v deep pockets, not conductive to non-surgical perio therapy

Molar teeth = if one root is more affected than the other = root resection or hemisection

Often, root resection undertaken on the mesio-buccal or disto-buccal roots of upper molar teeth and hemisection is undertaken on lower molars

Question 24

Prognosis of each perio-endo lesion?

Answer 24

Primary endo 2ndry perio = generally good prognosis

Primary perio 2ndry endo and true combined lesions = prognosis depends on extent of perio bone loss

Question 25

Lesions masquerading as perio-endo lesions?

Answer 25

Developmental grooves
Perforations
Root fracture
Resorption

Question 26

What can developmental grooves do?

Answer 26

Can predispose to formation of a deep perio pocket = if untreated can cause pulp death (primary perio 2ndry endo lesion)

Question 27

How to manage developmental grooves?

Answer 27

Endo tx and perio therapy but surgery may be required due to the groove

Question 28

Where can perforations occur?

Answer 28

Can occur during endo or during placement of an endodontic post or dentine pin

Question 29

How may the perforation clinically present?

Answer 29

Deep pocket leading to the site of perforation

May not be radiographically obvious as it’s a 2D image

Question 30

What can perforations lead to?

Answer 30

Bone loss around the site of the periodontium

Question 31

How to manage perforations?

Answer 31

Assessment of the restorability of the tooth
If unrestorable = extraction
Restorable = repair of the perforation either internally or externally using MTA or biodentine = biocompatible materials

Best performed by endodontist

Question 32

What may present in a similar way to perio-endo lesions? How?

Answer 32

Root fracture with a narrow, deep, isolated perio pocket

J shapes lesion may be present radiographically

Question 33

How to manage root fracture?

Answer 33

Assessing the extent of the fracture

Any vertical fracture extending onto the root face will require extraction

Question 34

What types of root resorption are relevant to perio-endo lesions?

Answer 34

External root resorption

• External cervical resorption
• External replacement resorption

Internal root resorption

Question 35

Features of external cervical root resorption?

Answer 35

Unknown aetiology
May be associated with previous trauma
Resorption usually starts subgingivally in the cervical region
Pulp is usually vital and only becomes involved when the lesion has progressed extensively
Often asymp
May be mistaken for perio endo lesion as pocketing may present
The resorption lesion fills with gingival tissue so the pocketing is rarely deep

Question 36

How to assess and treat external cervical root resorption?

Answer 36

CBCT may be useful to assess the extent of the lesion
Tx involves surgical exploration of the lesion followed by repair
Endo tx may or may not be required
= Specialist tx and referral should be instigated as soon as diagnosis is suspected

Question 37

External replacement resorption?

Answer 37

Root surface is gradually replaced with bone = ankylosis
Often has traumatic origin
Can be transient and self limiting but will often progress until complete root replacement occurs
Clinically when the lesion has progressed significantly a catch may be present at the gingival margin = can mimic a perio-endo lesion

Question 38

What does external replacement resorption diagnosis base on?

Clinical features?

Answer 38

Radiological appearance and clinical exam = high-pitched, metallic sound on percussion
May be non-mobile tooth and may become infra-occluded in children still growing

Question 39

How to treat the external replacement resorption?

Answer 39

No tx to stop the ankylosing process

Question 40

Internal root resorption features?

Answer 40

Occurs entirely in the canal system
Results in an ovoid expansion of the root canal
Outline of the canal will be lost around the area of resorption
Pulp will likely be chronically inflamed
Pink spot lesion may be visible through enamel if occurs in coronal aspect of tooth
Tooth is usually partially vital and there may be symptoms of pulpitis

Question 41

What occurs if internal root resorption continues to expand?

Answer 41

Eventually may perforate through the root = periodontal lesion may develop

Question 42

How to treat internal root resorption?

Answer 42

Endo tx
Obturation can be difficult due to unusual canal anatomy
Thermal obturation techniques (involving backfill with molten GP) is required