Bite Instability

Bite instability is a threshold condition at the system level.

It is not defined by a single worn tooth.

It is not defined by isolated fracture.

It is not defined by discomfort alone.

Bite instability exists when force distribution across the dentition produces progressive structural degradation over projected time, reducing long-term stability of multiple components.

The decision to intervene must be evaluated through structure, force, time, and long-term stability.

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

Structural evaluation includes:

Generalized enamel wear

Dentin exposure

Loss of posterior support

Recurrent fractures

Crack patterns across multiple teeth

Periodontal attachment levels

Loss of posterior support increases anterior load.

Generalized wear reduces structural tolerance.

Repeated restorative cycles reduce structural reserve across the arch.

Bite instability reflects cumulative structural compromise.

Force

Force evaluation includes:

Occlusal contact distribution

Parafunctional intensity

Lateral interferences

Asymmetrical loading

Muscular activity patterns

When posterior support diminishes, anterior teeth absorb greater force.

Lateral contacts amplify flexural strain.

Bruxism increases cyclic loading frequency.

Force becomes unevenly distributed, concentrating demand on compromised structure.

Time

Time projection includes:

Rate of wear progression

Frequency of fracture events

Accelerating restoration failure

Compliance with protective appliances

Progressive wear may appear gradual but accelerates as structural reserve decreases.

Repeated fracture events indicate that projected force across projected time already exceeds tolerance at localized sites.

Time converts imbalance into system-level instability.

Long-Term Stability

Long-term stability requires evaluating the dentition as an integrated biomechanical unit.

Isolated repair may temporarily stabilize a single tooth.

If force distribution remains unstable, failure recurs elsewhere.

Projected long-term stability must be assessed across the entire arch.

If preservation of the current occlusal scheme results in ongoing fracture cycles, projected long-term stability is unacceptable.

If redistribution of force improves structural balance and reduces projected instability, intervention becomes justified.

Threshold Identification

Threshold convergence occurs when projected force across projected time acting on cumulative structural compromise reduces long-term stability of the system below acceptable predictability.

Bite instability is present when:

Structure is globally reduced.

Force is unevenly distributed.

Time progression shows accelerating degradation.

Long-term stability under the current occlusal scheme is declining.

Intervention becomes responsible when redistribution of force improves projected stability relative to continued preservation.

Bite instability is not a symptom.

It is a convergence pattern across structure, force, time, and long-term stability.

The next chapter addresses replacement instability.