1. Endodontic Periodontal Lesions
Dr shabeel pn

2. Anatomic Considerations
There is an intimate relationship between the periodontium and pulpal tissues
As the tooth develops and the root is formed, 3 main avenues for communication are created:
Apical Foramen
Lateral and Accessory Canals
Dentinal Tubules
Fractures are an abnormal connection

3. Apical Foramen
It is the principal and the most direct route of communication between the pulp and periodontium
Bacterial and inflammatory byproducts may exit readily through the apical foramen to cause periapical pathosis
The apex may also serve as a portal of entry of inflammatory byproducts from deep periodontal pockets to the pulp
It is a two way pathway
From the pulp to the PDL, and from the PDL to the pulp

4. Apical Foramen
SEM of the apical third of a root. Note the opening of an accessory canal at ninety degrees from the main canal
They are not centered on the apex because there are lateral canals

5. Lateral and Accessory Canals
These may be present anywhere along the root
Patent accessory and lateral canals may serve as a potential pathway for the spread of bacterial byproducts
30-40% of all teeth have lateral or accessory canals and the majority of them are found in the apical third of the root

6. Lateral Canals The apical third has most of them
It is very difficult to instrument and obturate these canals so we count on the sealers to fill these canals otherwise the bacteria will continue to leak

7. Dentin Tubules
Exposed dentinal tubules in areas of denuded cementum may serve as communication pathways between the pulp and PDL
In the root, dentinal tubules extend from the pulp to the dentinocemental junction. They range in size from 1 to 3 microns in diameter (bacteria and their toxins are smaller in size)

8. Dentinal Tubules
Scanning electron micrograph of open dentinal tubules

9. Dentin Tubules
The tubules may be denuded of their cementum coverage as a result of perio disease, surgical procedures or developmentally when the cementum and enamel do not meet at the CEJ thus leaving areas of exposed dentin
Patients experiencing cervical dentin hypersensitivity are examples of such a phenomenon

10. Additional Avenues of communication between the Pulp and the Periodontium
Developmental malformations – such as palatogingival grooves of maxillary incisors. These usually begin in the central fossa, cross the cingulum, and extend apically with varying distances
Perforations – these may result from extensive carious lesions, resorption, or from operator error
Vertical root fractures – these can produce deep periodontal pocketing and localized destruction of alveolar bone. The fracture site provides a portal of entry for irritants from the root canal to the PDL
the periodentuim is usually attached with the malformation which is great, but the problem starts if there is perio disease then the bacteria can reach all the way down the palatogingical groove or malformation down to the apex and will cause de-vitalization or loss of the tooth due to perio disease

11. Additional Avenues of communication between the Pulp and the Periodontium
Resorption will cause a poor prognosis

12. Endodontic Disease and the Periodontium
When the pulp becomes inflamed or necrotic, inflammatory byproducts may leach out through the apex, lateral and accessory canals as well as the dentinal tubules to trigger an inflammatory vascular response in the periodontium
Seltzer and Bender 1967
You would see a lesion on the radiograph but it will not contain any bacteria only by-products that cause inflammation and loss of bone.

13. Periodontal Disease and the Pulp
The effect of periodontal inflammation on the pulp is controversial and conflicting studies exist:
It has been suggested that periodontal disease has no effect on the pulp, at least until it involves the apex (Czarnecki & Schilder, ‘79)
On the other hand, some studies suggest that the effect of perio disease on the pulp is degenerative in nature including an increase in calcifications, fibrosis and collagen resorption in the pulp (Langeland et al ‘74 and Mandi ‘72)
It has been reported that pulpal changes resulting from periodontal disease are more likely to occur when the apical foramen is involved (Langland et al ’74)
We do know that pulpal disease can cause periodontal inflammation and can loss of bone of bone in the periapical region.
A lot of studies show that perio disease doesn’t affect the pulp at least until it reaches the apex

14. Differential Diagnosis of Endo/Perio Lesions
The following classification system was developed by Simon, Glick and Frank in 1972:
Primary Endodontic Disease
Primary Periodontal Disease
Primary Endo w/ Secondary Perio
Primary Perio w/ Secondary Endo
True Combined Lesions

15. Differential Diagnosis of Endo/Perio Lesions
This is a simplification
If you have pulpal disease it can spread through the canals into the periodontal area and even through the apex, also furcation canals
You will see endo teeth with furcation involvement that is not due to perio.
Primary perio lesion you will have a vital pulp but the perio involvement is all the way to the apex and you will have a J-shaped lesion similar to the one you see in a vertical root fracture
True endo perio lesion, you have both conditions and the lesion meet in the middle
Endo lesion that has progressed for so long and worked its way up to the top

16. Primary Endodontic Disease
Typically, endodontic lesions resorb bone apically and laterally and destroy the attachment apparatus adjacent to a nonvital tooth
It is possible for an acute exacerbation of a chronic periapical lesion on a tooth with a necrotic pulp to drain through the PDL into the gingival sulcus. This clinical presentation mimics the presence of a periodontal abscess, or a deep periodontal pocket
Check if the tooth is vital or not
If it is vital then it is not an endo lesion

17. Primary Endodontic Disease
When endodontic infection drains through the PDL, the pocket is very narrow and deep. In reality, it is a sinus tract of pulpal origin that opens through the PDL, and not breakdown due to periodontal disease
A similar situation can occur where drainage from the apex of a molar tooth extends coronally into the furcation area. These cases resemble a “through-and-through” furcation defect (Grade III) of periodontal disease

18. Primary Endodontic Disease
For diagnostic purposes, it is imperative to trace the sinus tract by inserting a gutta-percha cone and exposing one or more radiographs to determine the origin of the lesion
The sinus tract of endodontic origin is readily probed down to the tooth apex, where no increased probing depth would otherwise exist around the tooth
Use an cone
Take two x-rays straight on and distal to localize the tract

19. Primary Endodontic Disease
Primary endodontic disease will heal following root canal treatment
The sinus tract extending into the gingival sulcus or the furcation area disappears at an early stage once the necrotic pulp has been removed and the root canals are well sealed
Vitality means perio
Another way to differentiate primary and endo from perio is that when you treat a primary perio with RCT the disease will not resolve.

20. Primary Endodontic Disease
Pre-op # Post-op yr follow-up
Tooth endo involved, lesion in apical and furcation area, the endo treatment was done and the areas healed

21. Primary Endodontic Disease
Pre-op #19: periapical and furcal RL + a deep narrow perio defect
PA and furcation involvement also

22. Primary Endodontic Disease
1 yr follow-up: complete healing of RL and buccal defect
The furcation healed and the probe doesn’t go in so much

23. Primary Periodontal Disease
Caused by periodontal pathogens
It is the result of progression of chronic periodontitis apically along the root surface
Pulp tests yield a clinically normal pulpal reaction

24. Primary Periodontal Disease
Frequently accumulation of plaque and calculus are seen throughout the dentition
Periodontal pockets are wider, and are generalized
The prognosis depends on the stage of periodontal disease and the efficacy of periodontal treatment

25. Primary Periodontal Disease
Pre-op: alveolar bone loss + a periapical lesion, a deep narrow pocket was traced on the mesial aspect of the root, the tooth tested vital
The first thing you want to check for this tooth vitality and it turned out to be vital
It also had a sinus tract
The lesion could be a little buccal to the apex

26. Primary Periodontal Disease
The tooth was extracted. Note the deep mesial radicular developmental groove

27. Primary Periodontal Disease
#31 was referred for RCT. The tooth tested vital to cold
Vital tooth
Referring dentist insisted on endo treatment

28. Primary Periodontal Disease
Referring dentist insisted that endo be done. However, since the etiology was periodontal disease, no bony healing took place
Did not heal after endo because it is not endo in origin

29. A periapical lesion of endodontic origin will not occur in the presence of a normal vital pulp!!!

30. Primary Endo with Secondary Perio
This happens with time as suppurating primary endodontic disease remains untreated, it may become secondarily involved with periodontal breakdown
Plaque forms at the gingival margin of the sinus tract and leads to plaque-induced periodontitis in the area
Untreated endo lesions that leads to perio problems
Calculus will build up in that area

31. Primary Endo with Secondary Perio
The pathway of inflammation into the periodontium is through the apical foramen, accessory and lateral canals
Periodontal break down and calculus formation from the apex upward

32. Primary Endo with Secondary Perio
The treatment and prognosis are now different than those of teeth simply having endo or perio disease
The tooth now requires both endodontic and periodontal treatments
If the endo Tx is adequate, the prognosis depends on the severity of the plaque-induced periodontitis and the efficacy of perio Tx
More complicated
The prognosis is different
The tooth will need both endo and perio treatment
If the perio involvement is only in the coronal third then there will be a better prognosis

33. Primary Endo with Secondary Perio
With endo Tx alone, only part of the lesion will heal to the level of the secondary periodontal lesion
Root fractures and perforations may also peresent as primary endo with secondary periodontal involvement

34. Primary Endo with Secondary Perio
Pre-op: interradicular defect extends to the apex Post-op

35. Primary Endo with Secondary Perio
1 yr follow-up: resolution of most of the periradicular lesion, however, a bony defect at the furcal area remained. Perio Tx is necessary for further healing
Now it needs perio treatment

36. Primary Perio with Secondary Endo
In this case, the apical progression of a periodontal pocket continues until the apical tissues are involved
The pulp may become necrotic as a result of infection entering via the apical foramen
Not always will become necrotic but it may become

37. Primary Perio with Secondary Endo
The progression of periodontitis by way of lateral canal and apex to induce a secondary endodontic lesion

38. Primary Perio with Secondary Endo
In single-rooted teeth the prognosis is usually poor, as the periodontal breakdown is very severe, necessitating extraction
In molar teeth the prognosis may be better, since not all the roots may suffer the same loss of supporting periodontium. Root resection may be considered as a treatment alternative
With the multirooted you can still save the remaining roots

39. Primary Perio with Secondary Endo
Even though unusual, the treatment of periodontal disease can also lead to secondary endodontic involvement. Lateral canals and dentinal tubules may be opened to the oral environment by scaling and root planing or surgical flap procedures

40. Primary Perio with Secondary Endo
At initial presentation #13 shows evidence of horizontal bone loss as well as a periapical radiolucency. The crown was intact, but vitality tests were negative. The post-op radiograph shows that a lateral canal was exposed to the oral environment due to bone loss. That lateral canal could serve as a potential pathway for bacteria.

41. True Combined Disease
True combined endo/perio disease occurs less frequently than other endo/perio problems
It is formed when an endodontic disease progressing coronally joins with an infected periodontal pocket progressing apically
The degree of attachment loss in this type of lesion is large and the prognosis is thus guarded, particularly for single-rooted teeth.
Prognosis is guarded specially in single rooted teeth

42. True Combined Disease
Concomitant endo-perio lesion is an additional classification that has been proposed to describe the presence of endo and perio disease as two separate and distinct entities

43. True Combined Disease
Radiograph shows separate progression of endodontic disease and periodontal disease. The tooth remained untreated and consequently the two lesions joined together

44. True Combined Disease
Radiograph shows bone loss in 2/3 of the root with calculus present and a separate periapical radiolucency. Clinical exam revealed coronal color change and pus exuding from the gingival crevice. Pulp vitality tests were negative

45. True Combined Disease
Endo treatment followed by surgical perio tx

46. Diagnosis
A thorough clinical and radiographic examination is imperative for developing a diagnosis
Data Collected must include:
periapical radiographs
pulp vitality testing: cold, EPT, cavity test
percussion
palpation
pocket probing
sinus tract tracking
cracked tooth testing: transillumination, tooth-slooth, staining

47. Treatment Decision-Making and Prognosis
Treatment decision-making and prognosis depend primarily on the diagnosis of the specific endodontic and/or periodontal disease
The main factors to consider are pulp vitality and type and extent of the periodontal defect

48. Treatment Decision-Making and Prognosis
Diagnosis of Primary endo and Primary perio disease usually present no clinical difficulty. In primary endo the pulp is nonvital. In primary perio the pulp is vital
However, the diagnosis of the combined endo/perio lesions could present a challege as they present clinically and radiographically very similar. The diagnosis is often tentative with a definitive diagnosis formulated following treatment

49. Treatment Decision-Making and Prognosis
The prognosis and treatment of each endo/perio disease type varies
Primary endo should only be treated by endodontic therapy and has a good prognosis
Primary perio should only be treated by periodontal treatment. The prognosis depends on severity of the perio disease and patient response to treatment

50. Treatment Decision-Making and Prognosis
Combined lesions should be treated with endodontic therapy first. Treatment should be evaluated in 2-3 months, and only then should periodontal treatment be considered. This sequence allows for sufficient time for initial tissue healing and better assessment of the periodontal condition to determine if the tooth needs SC/RP or surgical treatmen. Prognosis depends on the periodontal involvement and treatment
Cases of True Combined disease usually have a more guarded prognosis