FREE NDEB Endodontics and Periodontics Questions and Answers

Question 1

A patient presents with a deep, isolated 8mm periodontal pocket on the mesial aspect of a mandibular first molar, which has a necrotic pulp.
Radiographically, a periapical radiolucency is evident.
According to Simon's classification, what is the diagnosis and the correct initial treatment sequence?

Accepted Answer

Primary endodontic lesion with secondary periodontal involvement; initiate endodontic therapy first, then re-evaluate periodontal status.

Answer

Primary periodontal lesion; initiate periodontal debridement immediately.

Answer

True combined lesion; perform periodontal and endodontic therapy concurrently.

Answer

Concomitant pulpal and periodontal lesion; extract the tooth.

Question 2

A patient complains of a dull, persistent ache and discomfort on biting from an endodontically treated maxillary premolar. Probing reveals a deep, narrow pocket on the buccal aspect. A periapical radiograph shows a 'J-shaped' or 'halo' radiolucency extending from the apex along the side of the root. What is the most probable diagnosis?

Accepted Answer

Vertical root fracture

Answer

Condensing osteitis

Answer

Failed endodontic treatment due to a missed canal

Answer

Chronic apical periodontitis

Question 3

A 22-year-old patient presents for a routine check-up. A deep, narrow probing defect is found on the palatal aspect of the maxillary right lateral incisor. The tooth is vital, non-carious, and has no history of trauma. A radiograph reveals a faint, dark line running parallel to the root canal. Which of the following is the most likely cause of this localized periodontal defect?

Accepted Answer

A palatogingival groove

Answer

Aggressive periodontitis

Answer

Trauma from occlusion

Answer

An early primary endodontic lesion

Question 4

During a radiographic examination, a well-defined, oval radiolucency is seen within the confines of the root canal of a maxillary central incisor. The outline of the root canal appears ballooned and distorted, but the periodontal ligament space around the root is intact. What radiographic technique is most definitive in confirming the diagnosis?

Accepted Answer

Cone-shift technique (parallax)

Answer

Bitewing radiograph

Answer

Occlusal radiograph

Answer

Cone-beam computed tomography (CBCT)

Question 5

Which of the following scenarios has the poorest long-term prognosis, typically resulting in tooth extraction?

Accepted Answer

Vertical root fracture in an endodontically treated molar

Answer

Primary endodontic lesion with a draining sinus tract

Answer

Primary periodontal lesion with secondary endodontic involvement

Answer

Class II furcation involvement on a vital molar

Question 6

A patient requires treatment for a mandibular molar with a Class II furcation involvement and a concomitant diagnosis of pulpal necrosis. What is the most appropriate sequence of treatment to ensure the best possible outcome?

Accepted Answer

Complete endodontic therapy, wait 2-3 months for initial healing, then perform periodontal surgery.

Answer

Periodontal surgery first, followed by endodontic treatment after 3 months.

Answer

Concurrent endodontic and periodontal surgical treatment.

Answer

Extraction is the only predictable option.