perio-endo

Question 1

List the major pathways of communication between the pulp and periodontium tissue.

Answer 1

The possible pathways of communication between pulp and periodontium tissues include:
apical foramina (main direct communication);
lateral and accessory canals (most often located at the apical third of the root);
dentinal tubules; furcation canals;
developmental abnormality (e.g., palatogingival grooves on incisors);
and pathological or iatrogenic communications, including root resorption, vertical root fracture, and perforation (Seltzer, Bender & Ziontz 1963; Withers et al. 1981).

Question 2

Describe how pulpal pathosis works as a cause of periodontal disease in the case of a primary endodontic lesion with secondary periodontal involvement.

Answer 2

Canal debris, bacteria and bacterial byproducts can spread from the canal system to periodontium through the pathways described in answer A. In addition, during root canal therapy, the process of instrumentation, irrigation and placement of medicament may cause the extrusion of bacteria/ bacterial byproduct, irrigant or medicament beyond the apical foramen.The spread of these irritants may potentially aggravate the periodontal tissue.The above factors can cause inflammation or an infection process in the periodontium. If the pathogens overcome the host defense mechanism, it will lead to the destruction or loss of periodontal tissue (Blomlof, Lengheden & Linskog 1992; Jansson & Ehnevid 1998).

Question 3

What is the true combined endo–perio lesion?

Answer 3

A true combined endo–perio lesion refers to lesions originating from both endodontic and periodontal pathogens.They may occur concomitantly or independently. When lesions with different origins are coalesced, clinically it is very challenging to distinguish from other types of endo‐perio lesions, such as primary endodontic lesion with secondary periodontal involvement.

Question 4

Explain the differential diagnosis used in deter- mining whether a lesion is endo or perio in origin, including both clinical and radiographic factors.

Answer 4

The following examinations help the differential diagnosis between endodontic and periodontal disease (Silverstein et al. 1998).
a. Vitality test: In endodontic disease, the tooth is
non‐vital if pulp becomes necrotic; in periodontal
disease, the tooth is vital in most cases.
b. Plaque / calculus: In endodontic disease, plaque
or calculus may present, but they are not the primary cause of the disease; in periodontal disease, plaque or calculus is the primary cause.
c. Pocket/probing depth: In endodontic disease, a single and narrow pocket may present; in peri- odontal disease, generalized periodontal pockets may present and they are located relatively wide and coronally.
d. Radiographics: bone loss in endodontic disease is localized and mostly in the apical area; in periodontal disease, bone resorption is more generalized and mostly seen at the crestal bone.

Question 5

In addition to conventional endodontic and periodontal treatment, what are the alternative approaches that can be used to treat the lesions with combined endodontic and periodontal causes?

Answer 5

If the conventional treatment is insufficient, alternative treatments should be considered. These alternatives include root resection/amputation (removal of the affected root); and regenerative techniques such as guided tissue regeneration and guided bone regeneration (Duggins et al. 1994; Green 1986).