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ã Dr Keson B C TanBDS (Hons), MSD

ANTERIOR GUIDANCE


The dynamic relationship of the lower anterior teeth against the upper anterior teeth through all the ranges of function.

The influence of the contacting surfaces of anterior teeth on mandibular movements.

ANTERIOR GUIDANCE

Dawson, 1974

Glossary of Prosthodontic Terms,5th Edition, 1987


Class 3 Lever System


INTEARCH TOOTH ALIGNMENT

• Anterior guidance• Incisal edges Mand incisors vs

lingual fossae of Max incisors• Distal inclines Max lingual cusps vs

mesial inclines opposing fossae & marginal ridges

• Mesial inclines Mand buccal cusps vs distal inclines opposing fossae & marginal ridges

ProtrusiveOcclusal Contacts During Mandibular Movement


Anterior Determinants

Posterior Determinants


The protrusive movement has two elements that should be considered in articulation:

1) Condylar Inclination – pre-established by the patient;

and

2) Incisal Guidance - determined by the dentist’s judgement and influenced by the Esthetic and Functional needs of the patient.


Condylar Border Movements (i.e. the posterior controls) determine the outer limits of movement of the lower anterior teeth,

….. but they do not dictate the ……...

Envelope of Function i.e. how the lower anteriors functionally and dynamically relate to the palatal contours of the upper anterior teeth.


Effect of Condylar Guidance

Shallow CG

Short Cusp

Steep CG

Long Cusp


Effect of Vertical Overlap

Large VO

Long Cusp

Minimal VO

Short Cusp


Large HO

Short Cusp

Minimal HO

Long Cusp

Effect of Horizontal Overlap


Shallow CG + Large AG

Cusp Height possible

Effect of Condylar Guidance and Anterior Guidance

Shallow CG + Small AG

Short Cusp


Large ISS

Short Cusp

PSS + Minimal ISS

Long Cusp

Effect of ISS


Large ISS + Minimal AG

Short Cusp

Large ISS + AG

Cusp Height possible

Effect of ISS and Anterior Guidance


“Steep Anterior Guidance does not appear to expose the teeth to extreme lateral forces. The tooth gliding contacts while entering and leaving the intercuspal position have been shown to be of short duration & low magnitude when compared with the forces generated in the maximum intercuspal (MI) position. Occlusal stability in the intercuspal position (MI) is of utmost clinical significance.”

Charles H. Gibbs & Harry C. Lundeen (1982)


“Long Centric” ?


Anterior Coupling

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