**Core Concept:**

In dentistry, resistance form is an essential aspect of determining the fit and function of a dental restoration, such as a crown or bridge. An excessively tapered preparation refers to a dental preparation that has a steep taper which may lead to inadequate retention and stability of the restoration. The objective is to increase the resistance form to ensure a better fit and clinical performance.

**Why the Correct Answer is Right:**

The correct answer, D, suggests the process of **re-tapering** the preparation, which means modifying the steep taper to a more acceptable angle to improve the resistance form. Re-tapering involves reducing the taper of the preparation, thereby enhancing the retention and stability of the restoration. This modification ensures a more secure fit and reduces the risk of potential issues like loosening, fracture, or secondary caries due to inadequate retention.

**Why Each Wrong Option is Incorrect:**

A) Option A (keeping the excessive taper) maintains the excessive taper, which will result in an inadequate resistance form and compromise the retention and stability of the restoration.

B) Option B (increasing the axial wall thickness) addresses the mechanical integrity of the restoration but does not address the excessive taper issue, leading to a suboptimal resistance form.

C) Option C (reducing the axial wall height) primarily focuses on the vertical dimension alteration rather than the critical aspect of increasing the resistance form.

**Clinical Pearl:**

Increasing the resistance form of an excessively tapered dental preparation is crucial to ensure the longevity and success of the dental restoration. This principle applies to various dental restorative procedures, including crowns, bridges, and implant restorations. Regularly assessing and adjusting the preparation taper is essential to maintain optimal oral health and treatment outcomes.