## **Core Concept**
Obturation in endodontics refers to the process of filling and sealing the root canal system to prevent bacterial invasion and allow for healing. The decision to perform obturation in the initial visit, also known as one-visit endodontics, depends on specific clinical conditions.

## **Why the Correct Answer is Right**
The correct answer, **C. There is no exudate or purulent discharge**, indicates a situation where the canal is not actively infected or draining, making it suitable for immediate obturation. This is because the presence of exudate or purulent discharge signifies an ongoing infection that needs to be managed before obturation. When there is no exudate or purulent discharge, and the canal is properly cleaned and shaped, obturation can be successfully performed in the same visit.

## **Why Each Wrong Option is Incorrect**
- **Option A:** *There is a sinus tract present* - A sinus tract usually indicates a chronic infection that may require multiple visits to resolve.
- **Option B:** *The canal has a necrotic pulp* - Necrotic pulps often require more than one visit for proper disinfection and cleaning.
- **Option D:** *The tooth is non-restorable* - The restorability of the tooth does not directly dictate the timing of obturation but influences the overall treatment plan.

## **Clinical Pearl / High-Yield Fact**
A key clinical consideration for one-visit endodontics is the absence of symptoms and signs of active infection, such as exudate or purulent discharge. This approach can reduce treatment time but requires careful case selection to ensure long-term success.

## **Correct Answer:** . There is no exudate or purulent discharge