The colour of k file no 45 is
**Core Concept**
The color-coding of K-files is a standardized system used in endodontics to differentiate between files of varying sizes and tapers. This system is crucial for accurate identification and handling of files during root canal procedures.
**Why the Correct Answer is Right**
The color-coding system for K-files is based on the file size, with larger files having darker colors. The K-file No. 45 is a relatively small file, and its color is typically purple. The correct answer is purple because it corresponds to the size and taper of a K-file No. 45. This color-coding system helps dentists and endodontists to quickly identify the correct file for a specific procedure.
**Why Each Wrong Option is Incorrect**
**Option A:** Yellow - Yellow is typically associated with larger K-files, such as the K-file No. 60 or higher.
**Option B:** Green - Green is not a standard color for K-files, and it is often associated with other dental instruments.
**Option C:** Blue - Blue is used for some dental instruments, but it is not the standard color for K-file No. 45.
**Clinical Pearl / High-Yield Fact**
The color-coding system for K-files is a crucial aspect of endodontic practice, and it is essential to familiarize yourself with the colors and corresponding file sizes to ensure accurate identification and handling of files during procedures.
**Correct Answer: D. Purple.**