10.maxillomandibular relation records

10. Maxillo-mandibular Relation Records10. Maxillo-mandibular Relation Records

Eleni Roumanas DDSEleni Roumanas DDSDivision of Advanced Prosthodontics, Biomaterials and Division of Advanced Prosthodontics, Biomaterials and

Hospital DentistryHospital DentistryUCLA School of DentistryUCLA School of Dentistry

Frank Lauciello DDSFrank Lauciello DDSIvoclar VivadentIvoclar Vivadent

This program of instruction is protected by copyright ©. No portion of This program of instruction is protected by copyright ©. No portion of this program of instruction may be reproduced, recorded or transferred this program of instruction may be reproduced, recorded or transferred by any means electronic, digital, photographic, mechanical etc., or by by any means electronic, digital, photographic, mechanical etc., or by any information storage or retrieval system, without prior permission.any information storage or retrieval system, without prior permission.

Natural teeth are are suspended in the bone by the PDL which acts asNatural teeth are are suspended in the bone by the PDL which acts asa shock absorber.a shock absorber.

Denture teeth are part of the denture baseDenture teeth are part of the denture base which rests on movable/ which rests on movable/ displaceable tissuesdisplaceable tissues

Premature, deflective contactsPremature, deflective contacts between artificial teeth between artificial teeth cause cause movement of the denture resulting in damage to the supporting tissuesmovement of the denture resulting in damage to the supporting tissues

There Are Distinct Differences Between Natural There Are Distinct Differences Between Natural Dentition And Complete Denture Occlusion:Dentition And Complete Denture Occlusion:

Goals of Complete Denture OcclusionGoals of Complete Denture Occlusion

Limit trauma to the supporting structuresLimit trauma to the supporting structures

Preserve remaining structuresPreserve remaining structures

Enhance stability of the denturesEnhance stability of the dentures

Restore Esthetics, Speech and MasticationRestore Esthetics, Speech and Mastication

Balancin

g

ProtrusIve

Workin

g

Defn: is the Defn: is the simultaneous contactingsimultaneous contacting of the maxillary and mandibular of the maxillary and mandibular teeth in the teeth in the R and LR and L and in the and in the anterior and posterioranterior and posterior occlusal areas occlusal areas when the jaws are when the jaws are either in centric or eccentriceither in centric or eccentric relations. relations.

Balanced OcclusionBalanced Occlusion

Centric

RelationL

ingualized

Occlussion

Making Jaw Relation RecordsMaking Jaw Relation Records

In order to establish a balanced occlusion we must transfer our pts. In order to establish a balanced occlusion we must transfer our pts. maxillo-mandibular relationship to our articulator.maxillo-mandibular relationship to our articulator.

Facebow RecordFacebow Record

Records the orientation of the maxilla to the terminal hinge axis.Records the orientation of the maxilla to the terminal hinge axis.

Provides the same relative opening axis on the articulator as the Provides the same relative opening axis on the articulator as the mandible has to the TMJ. mandible has to the TMJ.

Defn:Defn:orients the maxilla to the orients the maxilla to the transverse axistransverse axis of the mandible of the mandible in in three dimensionsthree dimensions and allows the and allows the transfer of this orientation to the transfer of this orientation to the articulator.articulator.

Denar Hanau

Ivoclar

FacebowFacebow

Hinge AxisHinge Axis

Defn:A hypothetical line through the two mandibular Defn:A hypothetical line through the two mandibular condyles around which the mandible may rotate.condyles around which the mandible may rotate.

Arbitrary Hinge Axis:Arbitrary Hinge Axis:Is Is an estimated axis locationan estimated axis location, using, using

any of the current techniques willany of the current techniques willplace the position within place the position within ++6mm of the 6mm of the true hinge axis.true hinge axis.

EarbowsEarbows use the externaluse the externalauditory meatus reference point as the auditory meatus reference point as the arbitrary hinge axis location.arbitrary hinge axis location.

True Hinge Axis:True Hinge Axis:Is difficult to determine Is difficult to determine

especially in edentulous pts. and especially in edentulous pts. and requires special armamentarium.requires special armamentarium.

Hinge AxisHinge Axis

Place the maxillary record base andPlace the maxillary record base andwax rim in the pts. mouth and begin to wax rim in the pts. mouth and begin to contour it for proper phonetics, esthetics contour it for proper phonetics, esthetics lip support and occlusal plane. lip support and occlusal plane.

Wax Rim ContourWax Rim Contour

With the lips at rest the wax rim should project 1-2 With the lips at rest the wax rim should project 1-2 mm below the lip line.mm below the lip line.

Before adjustmentBefore adjustment After adjustmentAfter adjustment

Wax Rim ContourWax Rim Contour

Adjust the plane of the wax Adjust the plane of the wax rim so that it is parallel to rim so that it is parallel to Camper’s plane.Camper’s plane.

Adjust the plane of the wax Adjust the plane of the wax rim so that it is parallel to the rim so that it is parallel to the interpupillary line.interpupillary line.

Occlusal PlaneOcclusal Plane

Fox PlaneFox Plane

A A Fox PlaneFox Plane can be used to help can be used to help properly orient the occlusal plane.properly orient the occlusal plane.

Note the position occlusal plane in relation to the corners of the lips.

The Occlusal PlaneThe Occlusal Plane

Mark the midline on Mark the midline on the wax rim.the wax rim.

Determine MidlineDetermine Midline

Facebow Transfer RecordFacebow Transfer Record

Armamentarium

-Compound-Compound-Water bath-Water bath-Alcohol torch-Alcohol torch-Vaseline-Vaseline-Red handled knife-Red handled knife-Facebow-Facebow

Place notches in the maxillary wax rim as shown

Facebow Transfer Record

Index wax rim to bite fork with compound as Index wax rim to bite fork with compound as shownshown

vaselinevaseline thin layerthin layer

tempertemper center midlinecenter midline

soften compoundsoften compound

UTS-Universal Transferbow SystemUTS-Universal Transferbow System

Have the patient position the ear pieces. Have the patient position the ear pieces.

Place the nose piece on the bridge of the nose. This will Place the nose piece on the bridge of the nose. This will provide support for the entire earbow apparatus.provide support for the entire earbow apparatus.


Position the 3Position the 3rdrd point of reference at the base of the ala. point of reference at the base of the ala.The earpieces can be adjusted up or down to level the bow The earpieces can be adjusted up or down to level the bow parallel to the interpupillary line.parallel to the interpupillary line.


The record base, wax rim and bite fork are now inserted in the The record base, wax rim and bite fork are now inserted in the patients mouth and connected to the facebow.patients mouth and connected to the facebow.


Remove the facebow from the patient. Insert the maxillary Remove the facebow from the patient. Insert the maxillary cast into the record on the bite fork and attach the cast and cast into the record on the bite fork and attach the cast and face bow to the Stratos articulator with the mounting jig.face bow to the Stratos articulator with the mounting jig.

The record on the bite fork is The record on the bite fork is indexed to the maxillary wax indexed to the maxillary wax rimrim

Reminder:After mounting the upper cast,

make sure the incisal guide pin is at zero and in contact with the incisal guide table.


Articulator MountingsArticulator Mountings

The mounting is carefully smoothed The mounting is carefully smoothed and sanded. When you are finished and sanded. When you are finished allall your mountings must look like your mountings must look like this one.this one.

Refers to the Refers to the length of the face.length of the face.

It’s It’s the distance between two selected points, one on the the distance between two selected points, one on the fixed member (nose tip) and one on the movable member fixed member (nose tip) and one on the movable member (chin point).(chin point).

Is maintained either by the occlusion of the teeth(Is maintained either by the occlusion of the teeth(vertical vertical dimension of occlusion VDOdimension of occlusion VDO) or the balanced tonic ) or the balanced tonic contraction of the opening and closing muscles of contraction of the opening and closing muscles of mandibular movements (mandibular movements (vertical dimension of physiologic vertical dimension of physiologic rest position VDRrest position VDR).).

Determination of Vertical DimensionDetermination of Vertical Dimension

Establishing the vertical separation between the arches

These two measurable lengths of the face are important guides in making maxillomandibular relation records and are referred to as:

Vertical dimension of rest (VDR)Vertical dimension of occlusion (VDO)

Determination of Vertical DimensionDetermination of Vertical Dimension

PHYSIOLOGIC REST POSITION:In the absence of pathosis the

relation is fairly constant throughout life.

The position can be accurately recorded and measured within acceptable limits.

It is used to determine the vertical dimension of occlusion.

Defn: Is the vertical separation of the jaws when the opening & closing muscles of the mandible are at rest in tonic contraction. It is the length of the face when the mandible is in rest position.

Vertical Dimension of RestVertical Dimension of Rest

Establishing VDREstablishing VDR

Place the patient in an upright positionPlace marks on the tip of nose and the tip of the chin, on the greatest height of curvature. Make sure the chin is unstrained

“VDR”

1.1. Facial MeasurementsFacial Measurements-pt. sits comfortably,looking straight ahead-pt. sits comfortably,looking straight ahead-insert maxillary record base-insert maxillary record base--place point of reference on nose & chinplace point of reference on nose & chin-instruct pt. to lick lips and swallow-instruct pt. to lick lips and swallow-mandible comes to rest position-mandible comes to rest position-measure the distance between reference points-measure the distance between reference points

2.2. Tactile Sense- Tactile Sense- where pt. feels most comfortablewhere pt. feels most comfortable3.3. PhoneticsPhonetics

Repeat the letter “mm-mm” and relaxRepeat the letter “mm-mm” and relax4.4. Facial ExpressionFacial Expression

-recognize the pts relaxed facial expression when the jaws are at rest-recognize the pts relaxed facial expression when the jaws are at rest5.5. Anatomic landmarksAnatomic landmarks

-average measurements, questionable validity-average measurements, questionable validity

Establishing A Tentative VDREstablishing A Tentative VDR

*No one method for determining rest position can be accepted as being valid for all pts.; therefore, it is advisable to use several methods and compare the results

““Free-way space” or Interocclusal Rest Free-way space” or Interocclusal Rest Space-Space-Is the difference between the vertical Is the difference between the vertical dimension of rest and the vertical dimension dimension of rest and the vertical dimension of occlusionof occlusion

Vertical Dimension Of OcclusionVertical Dimension Of Occlusion

Defn: is Defn: is the distance measured when the teeth are in occlusionthe distance measured when the teeth are in occlusion

VDR-VDO =VDR-VDO =Free-way space Free-way space (range 2-4 mm)(range 2-4 mm)

Method of Obtaining VDOMethod of Obtaining VDO

Soften mandibular wax rim Soften mandibular wax rim with hot spatulawith hot spatula

Temper in Temper in water bathwater bath

Method of Obtaining VDOMethod of Obtaining VDO

Insert mandibular record baseInsert mandibular record baseHave patient bite down on the Have patient bite down on the

softened wax rim softened wax rim

Repeat until patient is Repeat until patient is at previously determined at previously determined VDO position.VDO position.

**VDR-(2-4mm)=VDOVDR-(2-4mm)=VDO

Interocclusal Rest Space:Freeway SpaceInterocclusal Rest Space:Freeway Space

“VDR”“VDO”

The distance between the occluding surfaces of the maxillary The distance between the occluding surfaces of the maxillary and mandibular teeth when the mandible is in its physiologic and mandibular teeth when the mandible is in its physiologic rest positionrest position

Interocclusal Rest Space

results in:results in:

-clickingclicking of the teeth of the teeth--facial distortionfacial distortion, tense strained , tense strained appearanceappearance--difficulty closing lipsdifficulty closing lips--difficulty swallowingdifficulty swallowing--soreness and discomfortsoreness and discomfort under the denture under the denture--increased ridge resorptionincreased ridge resorption due to trauma due to trauma

Inadequate Interocclusal Rest Space = Excessive VDOInadequate Interocclusal Rest Space = Excessive VDO

Inadequate Interocclusal Rest SpaceInadequate Interocclusal Rest Space

results in:results in:

-reduced interarch distancereduced interarch distance when the teeth are in when the teeth are in occlusionocclusion-overclosure is -overclosure is potentially damaging to the TMJpotentially damaging to the TMJ-normal -normal tongue space is limitedtongue space is limited--facial distortionfacial distortion, chin is closer to nose, , chin is closer to nose, commissure of the lips turns down , lips loose commissure of the lips turns down , lips loose their fullnesstheir fullness--musclesmuscles of facial expression of facial expression loose their tonicityloose their tonicity,,face appears flabbyface appears flabby--angular cheilitisangular cheilitis is sometimes attributed to is sometimes attributed to overclosureoverclosure

Excessive Interocclusal Rest Space= Inadequate VDOExcessive Interocclusal Rest Space= Inadequate VDO

Excessive Interocclusal Rest SpaceExcessive Interocclusal Rest Space

-Measures vertical dimension when the mandible and Measures vertical dimension when the mandible and muscles involved are in physiologic function of speech.muscles involved are in physiologic function of speech.

-The -The final testfinal test that we use to determine if the vertical that we use to determine if the vertical dimension of occlusion that we have chosen is correctdimension of occlusion that we have chosen is correct..

-Measure VDO of existing denture and compare.-Measure VDO of existing denture and compare.

-”s” sounds-”s” sounds-count from 60-70-count from 60-70

Closest Speaking SpaceClosest Speaking Space

Now that we have determined the Now that we have determined the vertical of occlusion how do we record vertical of occlusion how do we record the position of the mandible so that we the position of the mandible so that we can mount the mandibular cast on the can mount the mandibular cast on the articulator?articulator?

Maxillo-Mandibular RecordsMaxillo-Mandibular Records

Centric Occlusion(CO):Centric Occlusion(CO):Defn: is the relation of opposing occlusal surfaces that Defn: is the relation of opposing occlusal surfaces that provide provide maximum intercuspationmaximum intercuspation..

Centric Relation(CR):Centric Relation(CR):Defn: a maxillomandibular relationship in which Defn: a maxillomandibular relationship in which the condyles the condyles articulate with the thinnest avascular portion of their articulate with the thinnest avascular portion of their respective discs with the complex in the anterior-superior respective discs with the complex in the anterior-superior position against the slopes of the articular eminences.position against the slopes of the articular eminences.

Centric occlusionCentric occlusion with teeth present is a with teeth present is a tooth-to-toothtooth-to-tooth relation,whereas relation,whereas centric relationcentric relation, is a static position, is a , is a static position, is a bone bone to bone to bone relation.relation.

Centric RecordsCentric Records

1. Functional (Chew in)2. Graphic (Intraoral or extraoral tracings)3. Physiologic(Interocclusal records)

a. Waxes (i.e Alu-wax)b. Impression Compounds (ISO compound)c. ZOE paste

-waxes are capable of making a record upon contact and the jaws can be separated at once.-compound and ZOE must be maintained in contact until the material is hard-waxes are easily distorted and unless extreme care is exercised when the records are positioned, an error can occur-compound & ZOE will break before they will distort


ISO Compound

Material PropertiesMaterial Properties-Virtual is an addition-reaction silicone-Virtual is an addition-reaction silicone-Thixotropic viscocity-Thixotropic viscocity-Fast setting time-Fast setting time-Dimensionally stable-Dimensionally stable-Final hardness (95 Shore-A)-Final hardness (95 Shore-A)

Alternative Material- VirtualAlternative Material- Virtual

ApplicationApplication-Inject material on occlusal surfaces-Inject material on occlusal surfaces-Guide patient into a CR position-Guide patient into a CR position-Hold the position until material is set (60 sec.)-Hold the position until material is set (60 sec.)

The technique can be divided into 2 steps:The technique can be divided into 2 steps:

4.4. A tentative record using wax occlusion A tentative record using wax occlusion rims attached to accurate stable rims attached to accurate stable record bases.record bases.

8.8. Interocclusal check records with teeth Interocclusal check records with teeth arranged during the final try-in.arranged during the final try-in.

Alu-waxAlu-wax


1.1. CR is a CR is a reference pointreference point in recording maxillomandibular in recording maxillomandibular relations. It is independent of tooth contact. It allows usrelations. It is independent of tooth contact. It allows us

to record the to record the anterior-posterioranterior-posterior position of the mandible. position of the mandible.4.4. It can be It can be verified and repeatedverified and repeated5.5. It is a starting point for developing occlusionIt is a starting point for developing occlusion

In denture occlusion In denture occlusion CR=COCR=CO4.4. It’s a It’s a functional positionfunctional position, although fleeting in nature, although fleeting in nature.

Centric Relation RecordCentric Relation Record

*** CR should be recorded at the proper VDO

The primary requirements for makinga CR record:

4. Record the horizontal relation of the mandible to the maxilla at the proper

VDO.

8. Exert equal vertical pressure on the record base while making the record.

11. Avoid distortion of the record until the casts have been accurately mounted.

14. A record that cannot be repeated or verified is not acceptable.


Recording Centric RelationRecording Centric Relation

Before making the final record check Before making the final record check for interferences between the record for interferences between the record basesbases

Adjust record bases Adjust record bases as necessaryas necessary

If retention is lacking sprinkle a thin layer of powder If retention is lacking sprinkle a thin layer of powder adhesive onto the record baseadhesive onto the record baseTap off excess powderTap off excess powderWet the surfaceWet the surface

Denture AdhesiveDenture Adhesive

Making Making CRCR records consists of records consists of two phases:two phases:3.3. Getting the entire Getting the entire mandible retrudedmandible retruded

-Bimanual technique-Bimanual technique5.5. Positioning the Positioning the condyle-disc assemblycondyle-disc assembly

in the in the uppermost anterior positionuppermost anterior position..


Have patient practice Have patient practice closing gently in a retruded closing gently in a retruded position before making the position before making the final recordfinal record

Note: The casts and mountings are smoothed and sanded as shown

Mounting the mandibular cast:Mounting the mandibular cast:


The The movement the mandible and condyle movement the mandible and condyle is downward and forwardis downward and forward. . The angleThe angleof the slide varies from pt. to pt. and fromof the slide varies from pt. to pt. and fromside to side.side to side.

We will We will use this record to set condylar use this record to set condylar inclinationsinclinations so that the articulator can perform so that the articulator can perform eccentric movements equivalent to the eccentric movements equivalent to the relative movements of the mandible to the relative movements of the mandible to the maxillae. This makes it possible to arrange maxillae. This makes it possible to arrange the teeth for complete dentures in balanced the teeth for complete dentures in balanced occlusion.occlusion.

The mandible must be protruded a The mandible must be protruded a minimum of 5-6 mm when making the record.minimum of 5-6 mm when making the record.

Protrusive RecordProtrusive Record

Setting the Condylar InclinationSetting the Condylar Inclination

Loosen the centric locking pins on the Stratos 200 articulatorLoosen the centric locking pins on the Stratos 200 articulatorObserve the space that develops between the condylar Observe the space that develops between the condylar

elements when the casts are completely seated in the protrusive elements when the casts are completely seated in the protrusive recordrecord


Select a protrusive insert that best fits the spaceSelect a protrusive insert that best fits the space

Place the protrusive insert into positionPlace the protrusive insert into position

Orange20° protrusive insert

Note space remaining


Black Black 3030° protrusive insert° protrusive insert

Fits perfectly into positionFits perfectly into position& completely fills the space& completely fills the space

1. Seat pt. comfortably with head upright.Seat pt. comfortably with head upright.2. 2. Contour and mark the maxillary wax occlusion rimContour and mark the maxillary wax occlusion rim (lip (lip contour, midline, occlusal plane).contour, midline, occlusal plane).3. Make a 3. Make a facebow transfer recordfacebow transfer record and mount the maxillary and mount the maxillary cast.cast.4. Establish (a) 4. Establish (a) VDRVDR & (b) & (b) VDO VDO5. Make a tentative 5. Make a tentative CR recordCR record at the proper VDO at the proper VDO 6. Use CR record to mount the mandibular cast on the 6. Use CR record to mount the mandibular cast on the articulator.articulator.7. Make a 7. Make a Protrusive recordProtrusive record to set condylar inclinations. to set condylar inclinations.

Maxillomandibular Records in Summary:Maxillomandibular Records in Summary:

Alternate Technique- Centric TrayAlternate Technique- Centric Tray

The Centric Tray may be used to record The Centric Tray may be used to record a preliminary occlusal relationship. This a preliminary occlusal relationship. This can be quickly accomplished during the can be quickly accomplished during the impressions appointment. impressions appointment.

This record permits the laboratory technician This record permits the laboratory technician to mount the master casts prior to fabricating to mount the master casts prior to fabricating record bases and wax rims.record bases and wax rims.

The record can be verified at the following The record can be verified at the following appointment with the record bases.appointment with the record bases.

Alternate Technique- Centric TrayAlternate Technique- Centric Tray

Clinical Application:Clinical Application:

1) Determine the patients VDR 1) Determine the patients VDR and VDOand VDO

2) Load the try with heavy body 2) Load the try with heavy body Virtual and place in patients Virtual and place in patients mouth.mouth.

3) Have the patient close to the 3) Have the patient close to the previously determine verticalpreviously determine verticaldimension of rest.dimension of rest.

4) Allow the material to set and4) Allow the material to set andremove from the mouth.remove from the mouth.

Alternate Technique-Centric TrayAlternate Technique-Centric Tray

The UTS Transferbow is The UTS Transferbow is placed in positionplaced in position

The Centric Tray is gently insertedThe Centric Tray is gently inserted

Alternate Technique-Centric TrayAlternate Technique-Centric Tray

The Centric Tray is attached to theThe Centric Tray is attached to theTransferbow and secured in placeTransferbow and secured in place

Once the alignment of the transferbow is Once the alignment of the transferbow is verified and all theverified and all the set screws are securedset screws are secured the the apparatus is removed and ready for mounting.apparatus is removed and ready for mounting.

The Centric Tray is removed from the The Centric Tray is removed from the Transferbow and placed on the Stratos Transferbow and placed on the Stratos articulator. articulator.

Set the models in the silicone impression Set the models in the silicone impression and check the fit. Trim back the vestibular and check the fit. Trim back the vestibular edges of the silicone as necessary.edges of the silicone as necessary.

Mount the models on the articulator, Mount the models on the articulator, positioning them in relation to the occlusal positioning them in relation to the occlusal record.record.

THE END!THE END!

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10.maxillomandibular relation records