Centric Relation and Cross Mounting

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Centric Relation and Cross Mounting
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Facebow Transfer
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Centric Relation Basic Principles
anterior jig
Anterior Stop (anterior jig or leaf gauge) (no
posterior teeth should contact when making your
CR record) Minimal opening of the teeth Open
just enough to place the recording material
between the teeth.
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When to Make a Centric Relation Record?

• restoring all posterior teeth in one or both
  arches
• restoring all teeth in one arch
• complete denture
• occlusal equilibration

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When to Make a Centric Relation Record?

• restoring all posterior teeth in one or both
  arches
• restoring all teeth in one arch
• complete denture
• occlusal equilibration

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When to Make a Centric Relation Record?

• restoring all posterior teeth in one or both
  arches
• restoring all teeth in one arch
• complete denture
• occlusal equilibration

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When to Make a Centric Relation Record?

• restoring all posterior teeth in one or both
  arches
• restoring all teeth in one arch
• complete denture
• occlusal equilibration

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When to Make a Centric Relation Record?
Complete Denture Fabrication
anterior stop
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When to Make a Centric Relation Record?

• restoring all posterior teeth in one or both
  arches
• restoring all teeth in one arch
• complete denture
• occlusal equilibration

WHY?
Repeatable!
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Centric Relation Recording Techniques

• Two Techniques
• bimanual manipulation
• chin guidance

lucia jig (anterior jig)
anterior stop essential!
leaf gauge
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Leaf Gauge Record

• orofacial muscle exam
• examine and note the amount of horizontal and
  vertical overlap of teeth

The amount of horizontal overlap will remain the
same or slightly INCREASE depending on the amount
of discrepancy between a patients CR and MIP.
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Leaf Gauge Record
A reduction in the amount of horizontal overlap
is an indication that the patient is biting in
protrusive. The most common error when making a
CR record!
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Leaf Gauge

• 0.1mm thick polyester material
• numbered 1-55
• polyester material is flexible
• can be sterilized

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Leaf Gauge RecordBasic Principles

• place ten leaves between central incisors
• instruct the patient to close half hard on back
  teeth
• wait 20-30 seconds
• ask the patient if they feel contact of their
  back teeth

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Leaf Gauge RecordBasic Principles

• continue adding leaves (one at a time) until no
  posterior tooth contact can be felt
• (Record the number of leaves when the patient has
  no posterior contact)
• remove leaves one at a time to determine the
  first contact

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Leaf Gauge RecordBasic Principles

• Record the number of leaves when the patient
  feels tooth contact
• Record the location of the initial tooth
  contact. (teeth numbers and location on the
  teeth)

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Making the Centric Relation Record
increase the number of leaves when the patient
had no posterior contact by 5 leaves to allow for
the material verify that there is minimal but
adequate clearance between the maxillary and
mandibular teeth with the leaf gauge in
place place the President Jet Bite on the teeth
cover molar to canine bilaterally
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Making the Centric Relation Record
once the posterior teeth have been covered
bilaterally from molar to canine place the leaf
gauge in the anterior and have the patient close
as previously instructed trim the bite
registration to assure that the cast fully seats
in the record
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Leaf Gauge

• Advantages
• eliminates operator error
• (do not need to manipulate the patient into CR
  because of the flexible polyester material the
  leaves are made from)
• does not require fabrication of acrylic resin jig
• easy to use

• Criticisms
• patient may be in a strained position
• leaf gauge not transferable to cast for mounting

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Cross Mounting Procedure

• trim bite registration with scalpel until record
  fully seats on cast

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Cross Mounting Procedure