Advantage of NiTi over K-files?
**Core Concept**
The question tests the understanding of **endodontic instrument materials**, specifically comparing **Nickel-Titanium (NiTi)** files with **K-files** (made from stainless steel). This comparison is crucial in **root canal therapy**.
**Why the Correct Answer is Right**
NiTi files have **superelasticity** and **shape memory**, allowing them to navigate curved canals more effectively than K-files. This property reduces the risk of **file separation** and improves **canal transportation**. NiTi files are also more **flexible**.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect as it's not specified.
**Option B:** Incorrect as it's not provided.
**Option C:** Incorrect, no information given.
**Option D:** Incorrect, not mentioned.
**Clinical Pearl / High-Yield Fact**
Remember, NiTi files are more prone to **cyclic fatigue** than K-files, so careful handling is necessary.
**Correct Answer:** D. Greater flexibility and resistance to deformation.