**Question:** The hardest and most highly mineralized substance of tooth is called as

A. Dentin
B. Enamel
C. Pulp
D. Ceramic

**Core Concept:**
The tooth is a complex structure composed of various tissues, each with specific functions and properties. The hardest and most mineralized substance is a crucial aspect to understand, as it impacts the strength and resistance of the tooth to abrasions and decay. In the tooth, there are three main mineralized tissues: dentin, enamel, and cementum.

**Why the Correct Answer is Right:**
Among the options provided, the correct answer is **B. Enamel**. Enamel is the outer, visible layer of the tooth, and it is composed of hydroxyapatite crystals, which are the most mineralized and hard substances. Hydroxyapatite is a calcium phosphate compound (Ca10(PO4)6(OH)2), providing enamel with its exceptional hardness and resistance to wear.

**Why Each Wrong Option is Incorrect:**
Option **A. Dentin** is a softer tissue found beneath the enamel, composed of collagen fibers embedded in a mineral matrix. This makes it less resistant to wear and decay compared to enamel.

Option **C. Pulp** is the soft tissue in the center of the tooth, containing blood vessels, nerves, and connective tissue. It is not mineralized, making it irrelevant to the question's focus on mineralized substances.

Option **D. Ceramic** is a generic term for a man-made substance, not a term used for tooth tissues. Ceramics are used to fabricate dental restorations, such as crowns and veneers, but not a descriptor for tooth tissues.

**Clinical Pearl:**
Understanding the composition and properties of tooth tissues is crucial for dental professionals to diagnose, treat, and manage patients with oral health issues. Knowledge of mineralized substances in teeth allows for proper treatment planning, patient education, and prevention strategies.