Structure

Structure defines remaining physical integrity and geometric stability of the tooth and its supporting apparatus.

Structure is the foundational variable in the Structural Decision Framework™. It establishes baseline capacity before force and time are applied.

The Structural Decision Framework™ is a threshold-based clinical decision model in dentistry that evaluates irreversible treatment using four variables: structure, force, time, and long-term stability.

Structure includes:

Enamel thickness

Dentin volume

Remaining wall height

Cuspal integrity

Crack presence and orientation

Root morphology

Periodontal support

Structure exists along a continuum.

Minor enamel loss does not equate to instability.

Loss of marginal ridges reduces stiffness.

Cuspal undermining increases flexure.

Deep restorations reduce dentin thickness and increase fracture susceptibility.

Vertical cracks alter stress propagation patterns.

Structural evaluation must consider both quantity and geometry.

Remaining volume alone is insufficient. Configuration determines load distribution and resistance.

Two teeth may present similar dentin thickness.

One may have intact marginal ridges.

The other may have lost both ridges.

Their structural tolerance under projected force across projected time differs significantly.

Structure determines how force is absorbed, distributed, and transmitted.

Structural reserve refers to remaining load-bearing capacity beyond current demand.

Structural reserve is reduced by:

Repeated restorative cycles

Extensive cavity preparation

Endodontic access

Occlusal reduction

Periodontal attachment loss

Every irreversible intervention consumes structural reserve.

Structure cannot be fully restored to its original biological architecture once removed. Restorative materials replace function but do not replicate intrinsic resilience.

Structure must therefore be evaluated before alteration.

The clinician must determine:

How much structural reserve remains?

How is that reserve distributed?

How will additional reduction alter geometry?

Will modified structure tolerate projected force across projected time?

Structure must be quantified relative to force and time, not in isolation.

A tooth with limited structure may remain stable under minimal force.

A tooth with moderate structure may fail under high parafunctional load.

Structure defines capacity. It does not alone determine threshold.

Threshold convergence begins with structural evaluation but is confirmed only after integration with force, time, and long-term stability.

Structure is finite.

Structure is consumed by intervention.

Structure defines load tolerance.

Accurate structural assessment is required for reliable threshold identification.

The next chapter defines force.