The relation between the two jaws are called JAW RELATIONS Jaw Relations

Significance of recording jaw relation When teeth are lost due to various reasons We can see that the space occupied by the teeth is empty

Jaw relations

Our aim is to restore the lost structure very close to what was present

It is a clinical step. For it to be done we need to have Record Blocks for both upper and lower casts. They need to be prepared to the prescribed dimensions. Edentulous Patients Pre-requisites for Jaw Relations in Edentulous Patients

Record Block Parts of a Record Block Record Base + Occlusion Rims

Temporary Record Bases –These are materials which will be replaced during the final processing. They WILL NOT be part of the finished denture. –E.g., Shellac, Light-cure acrylic resin, Self-cure acrylic resin Permanent Record Bases –These are bases which WILL REMAIN as part of the final denture. –E.g., Heat-cure acrylic resin, Cast metal Bases. Materials in record base construction

JAW RELATIONS There are 3 Jaw Relations 1.Orientation Relation 2.Vertical Relation 3.Horizontal Relation

FACEBOW. To record Orientation one must use a FACEBOW. To take advantage of the use of a facebow we need an articulator that accepts a facebow transfer (a SEMI-ADJUSTABLE ARTICULATOR). ORIENTATION RELATION

What is an Occlussal Plane? The Occlussal Plane is the plane where the Occlussal aspect of the teeth will be.

A device helps us to visualize this parallelism. Fox Plane It is called the Fox Plane How can I check parallelism of the Occlussal Plane?

Posterior occlussal plane: Parallel to the ala tragus line.

VERTICAL RELATIONS

The vertical dimension of the face when the teeth are in contact. This is what we do NOT know because there are NO teeth!! Vertical Dimension of Occlusion

A. High Vertical Dimension Of Occlusion leads to: 1.There excessive display of the teeth and denture base. 2.Difficulty in swallowing. 3.Muscular fatigue. 4.Interference with speech. 5.Clicking of teeth on mastication and speech. 6.Pain under the denture base and trauma to the supporting structures. 7.High Vertical Dimension accelerates bone resorption. 8.TMJ problems. Effects of Improper Registration of Vertical Dimension of Occlusion

Methods of measuring Vertical Dimension

1.Centric Relation 2.Eccentric Relations –Right Lateral and Left Lateral Relation –Protrusive Relation HORIZONTAL RELATION

The Centric Relation Position is important because -  Centric Relation is a functional position  Centric Relation is guided into by the muscles and ligaments and so is verifiable and repeatable.  Centric Relation for a given Vertical Dimension.  Centric Relation is the starting point for developing the occlusion. Significance of the Centric Relation

1.Wax registration method. 2.Graphic tracing method. 3.Chew - in or functional method. Methods Of Centric Relation Registration

Jaw relation record transferred to the articulator