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2. ContentsContents
IntroductionIntroduction
Classification of jaw relationsClassification of jaw relations
Vertical jaw relationsVertical jaw relations
Physiologic rest positionPhysiologic rest position
hypothesishypothesis
factors to be consideredfactors to be considered
methods of recordingmethods of recording
significancesignificance
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3. Methods of recording vertical jaw relationsMethods of recording vertical jaw relations
mechanical methodsmechanical methods
physiologic methodsphysiologic methods
Tests to aid in confirming the correct verticalTests to aid in confirming the correct vertical
dimension.dimension.
Altered vertical dimensions and their effectsAltered vertical dimensions and their effects
ConclusionConclusion
ReferencesReferences
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5. IntroductionIntroduction
Complete dentures are constructed toComplete dentures are constructed to
function in the mouth as an integralfunction in the mouth as an integral
part of the masticatory apparatus &part of the masticatory apparatus &
there fore they should be designed tothere fore they should be designed to
conform to the patient’s physiologic jawconform to the patient’s physiologic jaw
relations.relations.
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6. To achieve this goal the recording mustTo achieve this goal the recording must
include an appropriate vertical relationinclude an appropriate vertical relation
of occlusion, stable occlusal contactsof occlusion, stable occlusal contacts
in harmony with the existing T.M.J andin harmony with the existing T.M.J and
masticatory muscle functions, and themasticatory muscle functions, and the
relationship between the prostheses &relationship between the prostheses &
oral & facial soft tissues andoral & facial soft tissues and
musculature.musculature.
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7. Mandibular MovementsMandibular Movements
The constant function of swallowingThe constant function of swallowing
saliva is the basis for establishing thesaliva is the basis for establishing the
mandibular position and occlusion.mandibular position and occlusion.
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8. In swallowing the saliva, mandibleIn swallowing the saliva, mandible
raises to its habitual closing terminalraises to its habitual closing terminal
and then as the saliva is forcedand then as the saliva is forced
backward into the pharynx by thebackward into the pharynx by the
tongue, the mandible is retruded to itstongue, the mandible is retruded to its
physiologic centric relation.physiologic centric relation.
These are the mandibular movementsThese are the mandibular movements
that are used in determining thethat are used in determining the
vertical relation and the centric relationvertical relation and the centric relation
for the complete dentures.for the complete dentures.www.indiandentalacademy.com
9. Classification of jaw relationsClassification of jaw relations
Jaw relations are classified into threeJaw relations are classified into three
groups. They are:-groups. They are:-
Orientation jaw relations.Orientation jaw relations.
Vertical jaw relations.Vertical jaw relations.
Horizontal jaw relations.Horizontal jaw relations.
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10. Vertical dimensionVertical dimension
Distance between the two selectedDistance between the two selected
anatomic or marked points ( usuallyanatomic or marked points ( usually
one on the top of the nose & the otherone on the top of the nose & the other
upon chin), one on a fixed & one on aupon chin), one on a fixed & one on a
movable member. [Gpt]movable member. [Gpt]
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11. Vertical jaw relationsVertical jaw relations
They are classified as :-They are classified as :-
Vertical dimension of rest.Vertical dimension of rest.
Vertical dimension of occlusion.Vertical dimension of occlusion.
Vertical dimension of other portions.Vertical dimension of other portions.
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12. Physiological rest positionPhysiological rest position
The Mandibular position assumedThe Mandibular position assumed
when the head is in an uprightwhen the head is in an upright
position and the involved musclesposition and the involved muscles
particularly the elevator andparticularly the elevator and
depressor groups are in equilibrium indepressor groups are in equilibrium in
tonic contraction, & the condyles aretonic contraction, & the condyles are
in a neutral , unstrained position.in a neutral , unstrained position.
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13. Vertical dimension of occlusionVertical dimension of occlusion
The distance measured between twoThe distance measured between two
points when the occluding memberspoints when the occluding members
are in contact.are in contact.
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14. Review of literatureReview of literature
Thompson and Brodie (1942) suggestedThompson and Brodie (1942) suggested
that the position of the mandible in relationthat the position of the mandible in relation
to the face and head is unchangeable as isto the face and head is unchangeable as is
the form of the mandible, and “thethe form of the mandible, and “the
proportions of any face as far as verticalproportions of any face as far as vertical
height is concerned, are constant throughheight is concerned, are constant through
out life.”out life.”
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15. Niswonger , Boos, and JaffeNiswonger , Boos, and Jaffe
apparently agree with this view.apparently agree with this view.
Leof (1950) believes that this relationLeof (1950) believes that this relation
is not constant but is readily affectedis not constant but is readily affected
by age, disease, and emotion.by age, disease, and emotion.
It seems that the constancy of theIt seems that the constancy of the
vertical maxillomandibular relationsvertical maxillomandibular relations
through out the life represents thethrough out the life represents the
unique phenomenon, not generallyunique phenomenon, not generally
found in relations of the other bones.found in relations of the other bones.
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16. Garnick and Ram fjord (1962) statedGarnick and Ram fjord (1962) stated
that rest position is a vertical rangethat rest position is a vertical range
rather than a point.rather than a point.
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17. Physiological rest positionPhysiological rest position
Vertical dimension of rest.Vertical dimension of rest.
Postural position of the mandible.Postural position of the mandible.
The postural position of the mandibleThe postural position of the mandible
when an individual is restingwhen an individual is resting
comfortably in an upright position andcomfortably in an upright position and
the associated muscles are in a state ofthe associated muscles are in a state of
minimal contractual activity.minimal contractual activity.
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18. This rest position is established by theThis rest position is established by the
muscles and gravity.muscles and gravity.
Two main hypothesis explain about theTwo main hypothesis explain about the
rest position of the mandible.rest position of the mandible.
One involves active mechanism.One involves active mechanism.
Second one involves the passiveSecond one involves the passive
mechanism.mechanism.
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19. But according to the current conceptsBut according to the current concepts
this position is actively determined.this position is actively determined.
The clinically recorded rest positionThe clinically recorded rest position
is usually 2- 4mm below theis usually 2- 4mm below the
maximum intercuspation position.maximum intercuspation position.
But according to the EMG activity aBut according to the EMG activity a
range of reduced muscle tension uptorange of reduced muscle tension upto
an interocclusal distance of about 10an interocclusal distance of about 10
mm is recorded. It is therefore moremm is recorded. It is therefore more
accurate to refer to a range of postureaccurate to refer to a range of posture
rather than to a single rest position.rather than to a single rest position.
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20. Factors to be considered whileFactors to be considered while
recording the rest positionrecording the rest position
Position of the mandible is influencedPosition of the mandible is influenced
by the gravity.by the gravity.
It is a relaxed position of the mandible.It is a relaxed position of the mandible.
Neuromuscular disturbances.Neuromuscular disturbances.
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21. Rest position is a position in space.Rest position is a position in space.
No one method for determining the restNo one method for determining the rest
position is a valid method.position is a valid method.
Space between the teeth is essentialSpace between the teeth is essential
when the mandible is at rest.when the mandible is at rest.
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22. Methods of recording the restMethods of recording the rest
positionposition
Facial measurements.Facial measurements.
Tactile sense.Tactile sense.
Phonetics.Phonetics.
Facial expression.Facial expression.
Anatomical landmarks.Anatomical landmarks.
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23. SignificanceSignificance
It is a bone to bone relation.It is a bone to bone relation.
In the absence of the pathosis theIn the absence of the pathosis the
relation is fairly constant through outrelation is fairly constant through out
the life.the life.
Position can be recorded andPosition can be recorded and
measured with in the acceptable limits.measured with in the acceptable limits.
It is used in determining the verticalIt is used in determining the vertical
dimension of occlusion.dimension of occlusion.
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24. Vertical dimension of occlusionVertical dimension of occlusion
Mechanical methodsMechanical methods
Ridge relation:-Ridge relation:-
1) Distance from the incisive papilla to1) Distance from the incisive papilla to
the mandibular incisors.the mandibular incisors.
2) Parallelism of the ridges.2) Parallelism of the ridges.
Measurement of the former dentures.Measurement of the former dentures.
Preextraction records:-Preextraction records:-
1)Profile radiographs.1)Profile radiographs.
2)Casts of the teeth in occlusion.2)Casts of the teeth in occlusion.
3)Facial measurements.3)Facial measurements.
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27. The incisal edges ofThe incisal edges of
the maxillary centralthe maxillary central
incisors are an averageincisors are an average
6 mm below the6 mm below the
incisive papilla. So theincisive papilla. So the
average verticalaverage vertical
overlap is about 2 mm.overlap is about 2 mm.
This relationship ofThis relationship of
maxillary andmaxillary and
mandibular anteriormandibular anterior
teeth concerns not onlyteeth concerns not only
the vertical ridgethe vertical ridge
height but also estheticheight but also esthetic
values.values.
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28. Disadvantage:Disadvantage:
In the absence of lower anterior teeth,In the absence of lower anterior teeth,
this method cannot be used.this method cannot be used.
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29. Parallelism of ridges:Parallelism of ridges:
Paralleling of maxillary and mandibularParalleling of maxillary and mandibular
ridges plus 5 degree opening in theridges plus 5 degree opening in the
posterior region as suggested by searsposterior region as suggested by sears
often gives a clue to the amount of jawoften gives a clue to the amount of jaw
separation.separation.
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31. Disadvantages:Disadvantages:
This theory cannot be used whenThis theory cannot be used when
there is great amount of bone lossthere is great amount of bone loss
which would change the ridge relation,which would change the ridge relation,
also if the patient has lost the teeth atalso if the patient has lost the teeth at
irregular intervals, the line of ridges isirregular intervals, the line of ridges is
naturally thrown out of parallelnaturally thrown out of parallel..
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32. Measurement of former dentures:Measurement of former dentures:
Measurement between the borders ofMeasurement between the borders of
the maxillary and mandibular denturesthe maxillary and mandibular dentures
can be made and can be correlatedcan be made and can be correlated
with the observation of the patientswith the observation of the patients
face to determine the amount offace to determine the amount of
change required.change required.
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33. Measurement of former denturesMeasurement of former dentures
using Boley’s gaugeusing Boley’s gauge
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35. Pre extraction recordsPre extraction records
When natural teeth are in maximumWhen natural teeth are in maximum
occlusion, the jaws are not necessarilyocclusion, the jaws are not necessarily
in centric relation.in centric relation.
For this reason all the pre extractionFor this reason all the pre extraction
records must be evaluated.records must be evaluated.
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36. Profile radiographsProfile radiographs
Radiograph before extraction must beRadiograph before extraction must be
taken and preserved.taken and preserved.
After extraction and after establishingAfter extraction and after establishing
the tentative jaw relation, anotherthe tentative jaw relation, another
radiograph should be taken.radiograph should be taken.
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37. The two radiographs must beThe two radiographs must be
super imposed and compared.super imposed and compared.
The inaccuracies that exist in either theThe inaccuracies that exist in either the
technique or the method of comparingtechnique or the method of comparing
measurements make these methodsmeasurements make these methods
unreliable.unreliable.
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39. Profile photographsProfile photographs
Profile photographs are made andProfile photographs are made and
enlarged to life size. The photographenlarged to life size. The photograph
should be made with teeth inshould be made with teeth in
maximum occlusion.maximum occlusion.
Measurements of anatomical landMeasurements of anatomical land
marks are compared with themarks are compared with the
measurements of face using samemeasurements of face using same
land marks .land marks .
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40. Disadvantages:-Disadvantages:-
Angulations of photographs might differAngulations of photographs might differ
with the patients posture.with the patients posture.
Enlargement can cause inaccuracies.Enlargement can cause inaccuracies.
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41. Profile tracing:Profile tracing:
Lead wire adaptation .Lead wire adaptation .
This method is full of pitfalls as it isThis method is full of pitfalls as it is
not possible to contour the wirenot possible to contour the wire
accurately against the soft tissueaccurately against the soft tissue
without producing distortion.without producing distortion.
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42. A piece of soft lead wire is molded toA piece of soft lead wire is molded to
contour of the face starting from thecontour of the face starting from the
eyebrow to just below the chin alongeyebrow to just below the chin along
the midline. Then the contour isthe midline. Then the contour is
transferred to the cardboard. Thetransferred to the cardboard. The
resultant cutout is stored andresultant cutout is stored and
compared to by placing against thecompared to by placing against the
profile which is established after theprofile which is established after the
extraction and estimation of theextraction and estimation of the
vertical relation using the recordvertical relation using the record
blocks.blocks.
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43. Profile silhouettesProfile silhouettes
SimilarSimilar to profile tracing.to profile tracing.
An accurateAn accurate reproduction of the profilereproduction of the profile
silhouettes can be cutout in asilhouettes can be cutout in a
cardboard. Then the silhouettes can becardboard. Then the silhouettes can be
positioned onto the face necessarypositioned onto the face necessary
adjustments can be made.adjustments can be made.
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44. Diagnostic castsDiagnostic casts
Various methods to determine verticalVarious methods to determine vertical
relation of occlusion by using therelation of occlusion by using the
diagnostic casts.diagnostic casts.
Heinz and Peters method.Heinz and Peters method.
Quinn et al method.Quinn et al method.
Bissasu method.Bissasu method.
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45. Casts of teeth articulated in occlusionCasts of teeth articulated in occlusion
Heinz and peters methodHeinz and peters method
Accurate casts of maxillary andAccurate casts of maxillary and
mandibular arches made.mandibular arches made.
The maxillary cast is related to itsThe maxillary cast is related to its
correct anatomic position on ancorrect anatomic position on an
articulator with a face bow transfer.articulator with a face bow transfer.
An occlusal record with the jaws inAn occlusal record with the jaws in
centric relation is used to mount thecentric relation is used to mount the
mandibular cast.mandibular cast.
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46. After the teeth has been removed,After the teeth has been removed,
edentulous casts are mounted on theedentulous casts are mounted on the
articulator, the interarch measurementsarticulator, the interarch measurements
are compared and necessaryare compared and necessary
adjustments are made.adjustments are made.
They give information of the verticalThey give information of the vertical
overlap and size and shape of teeth.overlap and size and shape of teeth.
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47. The casts also assist in theThe casts also assist in the
selection of size, shape andselection of size, shape and
position of the teeth.position of the teeth.
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48. Disadvantage:Disadvantage:
It cannot used when there is a longIt cannot used when there is a long
waiting period for fabrication ofwaiting period for fabrication of
denture after extraction.denture after extraction.
It cannot be used when there isIt cannot be used when there is
excessive bone loss during theexcessive bone loss during the
extraction procedure.extraction procedure.
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49. Quinn et al methodQuinn et al method
Quinn et al made maxillary & mandibularQuinn et al made maxillary & mandibular
record bases and wax occlusion rims.record bases and wax occlusion rims.
Recorded the maxillo mandibularRecorded the maxillo mandibular
relationship and made wax flanges for therelationship and made wax flanges for the
dentate areas of diagnostic casts.dentate areas of diagnostic casts.
The maxillary and mandibular record bases,The maxillary and mandibular record bases,
wax flanges, and the stone teeth werewax flanges, and the stone teeth were
duplicated in a duplicating flask usingduplicated in a duplicating flask using
reversible hydrocolloid impression material.reversible hydrocolloid impression material.
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50. The replica wax bases are used for makingThe replica wax bases are used for making
the definitive impression, the resultant stonethe definitive impression, the resultant stone
casts and the replica wax bases and the waxcasts and the replica wax bases and the wax
teeth are mounted in an articulator inteeth are mounted in an articulator in
maximal intercuspation, and the artificialmaximal intercuspation, and the artificial
teeth are arranged with the impressionteeth are arranged with the impression
material in place.material in place.
Disadvantages :- 1) This method requiredDisadvantages :- 1) This method required
additional proceduresadditional procedures
2) Time consuming.2) Time consuming.
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51. Use of lingual frenum BissasuUse of lingual frenum Bissasu
Bissasu proposed in determining theBissasu proposed in determining the
original vertical relation by measuring theoriginal vertical relation by measuring the
distance between the center of thedistance between the center of the
Incisive papilla and the incisal edges of theIncisive papilla and the incisal edges of the
maxillary central incisors and between themaxillary central incisors and between the
anterior attachment of the lingual frenumanterior attachment of the lingual frenum
and then adjusting the maxillary andand then adjusting the maxillary and
mandibular wax occlusion rims, anteriorly,mandibular wax occlusion rims, anteriorly,
to correspond with these measurements.to correspond with these measurements.
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52. Advantages :-Advantages :-
Method is simpleMethod is simple
Does not require any additionalDoes not require any additional
armamentariumarmamentarium
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53. Facial measurements:Facial measurements:
These are also pre-extraction guides.These are also pre-extraction guides.
Various devices for making facialVarious devices for making facial
measurements are used in differentmeasurements are used in different
forms.forms.
DakometerDakometer
Willis gaugeWillis gauge
Orofacial deviceOrofacial device
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54. DakometerDakometer
The instruments record both verticalThe instruments record both vertical
dimension with the natural teeth indimension with the natural teeth in
occlusion and the position of centralocclusion and the position of central
incisors. In most cases recording canincisors. In most cases recording can
be obtained with an error range of +be obtained with an error range of +
or - 1mm.or - 1mm.
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56. Willis gaugeWillis gauge
The instrument is used for recordingThe instrument is used for recording
vertical height, before extraction.vertical height, before extraction.
The arm (A) is placed in contact withThe arm (A) is placed in contact with
the base of the nose and arm (B) isthe base of the nose and arm (B) is
moved along the slide (D) until it ismoved along the slide (D) until it is
firmly and lightly touching the lowerfirmly and lightly touching the lower
border of the chin, then it is locked inborder of the chin, then it is locked in
position by the screw (C). The distanceposition by the screw (C). The distance
on the scale (D) is recorded andon the scale (D) is recorded and
preserved.preserved. www.indiandentalacademy.com
57. Disadvantage:Disadvantage:
It is not accurate because theIt is not accurate because the
degree of pressure applied every timedegree of pressure applied every time
may not be the same.may not be the same.
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60. Aabu-Ela and Razek methodAabu-Ela and Razek method
They have recorded the vertical relation ofThey have recorded the vertical relation of
occlusion by the use of an orofacial device.occlusion by the use of an orofacial device.
The upper portion of the device extendedThe upper portion of the device extended
between the orbital point and the externalbetween the orbital point and the external
auditory meatus to form the Frankfort plane.auditory meatus to form the Frankfort plane.
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61. The lower part of the device is placedThe lower part of the device is placed
against the inferior border of the mandibleagainst the inferior border of the mandible
and pressed gently against the mandible.and pressed gently against the mandible.
This part of the device formed theThis part of the device formed the
mandibular planemandibular plane..
The angle that was formed by the junction ofThe angle that was formed by the junction of
Frankfort and the mandibular plane wasFrankfort and the mandibular plane was
recorded.recorded.
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62. After the removal of the teeth duringAfter the removal of the teeth during
recording of the vertical relation of occlusionrecording of the vertical relation of occlusion
of the edentulous patient, the wax occlusionof the edentulous patient, the wax occlusion
rims are reduced or increased until therims are reduced or increased until the
previously recorded angle is duplicated thuspreviously recorded angle is duplicated thus
restoring the VDO.restoring the VDO.
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63. Facial measurements using tattooFacial measurements using tattoo
Permanent tattoo markings are placedPermanent tattoo markings are placed
one on the upper half of face andone on the upper half of face and
another on lower half of face.another on lower half of face.
The distance is measured andThe distance is measured and
preserved. These measurements arepreserved. These measurements are
compared when artificial teeth arecompared when artificial teeth are
tried.tried.
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64. Silverman has also suggested theSilverman has also suggested the
placement of tattoo marking on theplacement of tattoo marking on the
patient’s upper and lower gingiva,patient’s upper and lower gingiva,
slightly, left to the middle betweenslightly, left to the middle between
attached gingiva in depth of vestibule.attached gingiva in depth of vestibule.
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65. Disadvantage:Disadvantage:
Patient may not agree forPatient may not agree for
placement of permanent tattoo marks.placement of permanent tattoo marks.
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66. Swenson’s acrylic face mask:Swenson’s acrylic face mask:
Swenson’s described theSwenson’s described the
construction of acrylic resin faceconstruction of acrylic resin face
mask of the lower third of the face asmask of the lower third of the face as
a record for future determination ofa record for future determination of
vertical dimension.vertical dimension.
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68. Disadvantages:Disadvantages:
Time consuming.Time consuming.
Requires lot of skill and experience toRequires lot of skill and experience to
make impression of the face.make impression of the face.
Face assumes a different topography inFace assumes a different topography in
the erect posture from that in thethe erect posture from that in the
recumbent or semi-recumbent positionrecumbent or semi-recumbent position
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69. The method suggested by Wright:The method suggested by Wright:
Wright marked the followingWright marked the following
measurements from photographsmeasurements from photographs
The interpupillary distanceThe interpupillary distance
Brow chin distanceBrow chin distance
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70. Interpupillary interpupillary brow chin brow chinInterpupillary interpupillary brow chin brow chin
distance in : distance : : distance in : distancedistance in : distance : : distance in : distance
Photograph of patient in photograph of patientPhotograph of patient in photograph of patient
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72. Niswonger methodNiswonger method
Niswonger suggested thisNiswonger suggested this
method in 1934.method in 1934.
This method along with phoneticsThis method along with phonetics
and esthetics is commonly usedand esthetics is commonly used
today.today.
The patient is seated in suchThe patient is seated in such
away that ala -tragus line isaway that ala -tragus line is
parallel to the floor.parallel to the floor.
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73. There upon two marks , one at the baseThere upon two marks , one at the base
of the nose and one on the chin areof the nose and one on the chin are
made.made.
The patient is told to swallow and relax .The patient is told to swallow and relax .
the distance between the two marks isthe distance between the two marks is
measured and recorded .measured and recorded .
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74. Subsequently the occlusal rims areSubsequently the occlusal rims are
constructed so that when they meet theconstructed so that when they meet the
measured distance is 1/8 inch (2-4mm)measured distance is 1/8 inch (2-4mm)
less than original distance. This 1/8less than original distance. This 1/8
inch is the average freeway space.inch is the average freeway space.
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75. DisadvantageDisadvantage::
As the marks are on the skin,As the marks are on the skin,
they tend to move with the skin. So it isthey tend to move with the skin. So it is
difficult to obtain two constantdifficult to obtain two constant
measurements of the rest position.measurements of the rest position.
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77. Concept of equal thirds:Concept of equal thirds:
Willis suggested that the face can beWillis suggested that the face can be
divided into equal thirds, the forehead,divided into equal thirds, the forehead,
the nose, the lips and the chin.the nose, the lips and the chin.
However this concept is of littleHowever this concept is of little
practical value as the points ofpractical value as the points of
measurements are entirely vague.measurements are entirely vague.
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78. Vertical dimension by means ofVertical dimension by means of
power point or Boos methodpower point or Boos method
Boos in 1940 stated that there was aBoos in 1940 stated that there was a
point of maximum biting power.point of maximum biting power.
He says that the patient registers theHe says that the patient registers the
greatest amount of pressure on agreatest amount of pressure on a
spring dynamometer at a point.spring dynamometer at a point.
So the Bimeter is used in this principle.So the Bimeter is used in this principle.
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79. The Bimeter is attached to an accuratelyThe Bimeter is attached to an accurately
adapted mandibular record base.adapted mandibular record base.
A metal plate is attached to the vault ofA metal plate is attached to the vault of
an accurately adapted maxillary recordan accurately adapted maxillary record
base to provide a central bearing point.base to provide a central bearing point.
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80. Adjust the vertical distance by turningAdjust the vertical distance by turning
the cap.the cap.
The gauge indicates the pounds ofThe gauge indicates the pounds of
pressure generated during jaw closurepressure generated during jaw closure
at different degrees of jaw separation.at different degrees of jaw separation.
When the maximum PowerPoint isWhen the maximum PowerPoint is
reached, the lock nut is set, plasterreached, the lock nut is set, plaster
registration is made.registration is made.
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81. Phonetics as a guidePhonetics as a guide
Silverman’s closest speaking space methodSilverman’s closest speaking space method..
Proposed by Silverman in 1952.Proposed by Silverman in 1952.
Silverman identified that the production ofSilverman identified that the production of
certain sounds like “S” “yes”,”J” , “ch” bringscertain sounds like “S” “yes”,”J” , “ch” brings
the anterior teeth very close together.the anterior teeth very close together.
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82. Direct the patient into centricDirect the patient into centric
occlusion and draw the line on a lowerocclusion and draw the line on a lower
anterior teeth at the horizontal levelanterior teeth at the horizontal level
of the incisal edges of the opposingof the incisal edges of the opposing
upper anterior teeth. This is called theupper anterior teeth. This is called the
centric occlusion line.centric occlusion line.
Ask the patient to sayAsk the patient to say yesyes and whileand while
the phonetic soundthe phonetic sound ss is pronounced,is pronounced,
draw the closest speaking line on thedraw the closest speaking line on the
same lower anterior teeth at thesame lower anterior teeth at the
horizontal level of the upper incisalhorizontal level of the upper incisal
edge.edge.
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83. The distance between these two linesThe distance between these two lines
is called the closest speaking space.is called the closest speaking space.
The measurements ranged fromThe measurements ranged from
0 to 10 mm.0 to 10 mm.
The closest speaking space asThe closest speaking space as
measured in the natural dentition mustmeasured in the natural dentition must
be reproduced in complete denturesbe reproduced in complete dentures
after the loss of remaining naturalafter the loss of remaining natural
teeth.teeth.
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84. This method aids the dentist toThis method aids the dentist to
evaluate the vertical dimension ofevaluate the vertical dimension of
occlusion.occlusion.
When correctly placed the lowerWhen correctly placed the lower
incisors move forward to a positionincisors move forward to a position
nearly directly under the upper centralnearly directly under the upper central
incisors and come close to them but doincisors and come close to them but do
not contact.not contact.
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85. The position of the tongue and itsThe position of the tongue and its
relation to the teeth is also anrelation to the teeth is also an
important factor, by asking the patientimportant factor, by asking the patient
to pronounce repeatedly the numberto pronounce repeatedly the number
“thirty three”.“thirty three”.
The dentist can evaluate if there isThe dentist can evaluate if there is
enough space for the tip of the tongueenough space for the tip of the tongue
to protrude between the anterior teeth.to protrude between the anterior teeth.
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86. Swallowing threshold : ShanabanSwallowing threshold : Shanaban
Thomas :Thomas :
Swallowing reflex is a primitive, innate reflex.Swallowing reflex is a primitive, innate reflex.
The position of the mandible at theThe position of the mandible at the
beginning of the swallowing act has beenbeginning of the swallowing act has been
used as a guide to the vertical relation. Theused as a guide to the vertical relation. The
theory behind this method is that when atheory behind this method is that when a
person swallows, the teeth come togetherperson swallows, the teeth come together
with a very light contact at the beginning ofwith a very light contact at the beginning of
swallowing cycle.swallowing cycle.
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87. The technique involves building aThe technique involves building a
cone of soft wax on the lower denturecone of soft wax on the lower denture
base so that it contacts the upperbase so that it contacts the upper
occlusion rim with the jaws too wideocclusion rim with the jaws too wide
open.open.
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88. The flow of saliva is stimulated and theThe flow of saliva is stimulated and the
repeated action of swallowing the saliva willrepeated action of swallowing the saliva will
gradually reduce the height of the wax conesgradually reduce the height of the wax cones
to allow the mandible to reach the level ofto allow the mandible to reach the level of
occlusal vertical dimension.occlusal vertical dimension.
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89. Facial expression and esthetics as aFacial expression and esthetics as a
guide:guide:
The experienced dentist learns theThe experienced dentist learns the
advantage of recognizing the relaxedadvantage of recognizing the relaxed
facial expression when the jaws are atfacial expression when the jaws are at
rest. In normally related jaws, the lipsrest. In normally related jaws, the lips
will be even anteroposteriorly and inwill be even anteroposteriorly and in
slight contact.slight contact.
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90. The lips of the patient in case ofThe lips of the patient in case of
protruded mandible will not be evenlyprotruded mandible will not be evenly
related , the lower lip will be anterior torelated , the lower lip will be anterior to
the upper lip and not in contact. In casethe upper lip and not in contact. In case
of retruded mandible the lower lip willof retruded mandible the lower lip will
be distal to the upper lip and not inbe distal to the upper lip and not in
contact.contact.
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91. When the vertical dimension isWhen the vertical dimension is
increased both the, mentolabial andincreased both the, mentolabial and
nasolabial grooves disappear when V.Dnasolabial grooves disappear when V.D
is decreased the grooves areis decreased the grooves are
exaggerated and the chin appears closeexaggerated and the chin appears close
to the nose.to the nose.
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92. Based on harmony of faceBased on harmony of face
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93. Neuromuscular perception andNeuromuscular perception and
tactile sense:tactile sense:
The stretch reflex and proprioceptiveThe stretch reflex and proprioceptive
mechanisms of muscles and ligamentsmechanisms of muscles and ligaments
of temporomandibular joints areof temporomandibular joints are
retained in the fully edentulous patient.retained in the fully edentulous patient.
A number of studies have been done byA number of studies have been done by
using this neuromuscular memory tousing this neuromuscular memory to
determine the V.D of occlusion withdetermine the V.D of occlusion with
mixed success (Lytle 1964, Tryde et al)mixed success (Lytle 1964, Tryde et al)
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94. Tactile sense method:Tactile sense method:
The tactile sense of the patient is usedThe tactile sense of the patient is used
as a guide in the determination of theas a guide in the determination of the
occlusal vertical relation.occlusal vertical relation.
An adjustable central bearing screw isAn adjustable central bearing screw is
attached in the palate of the maxillaryattached in the palate of the maxillary
denture base or occlusal rim. Thedenture base or occlusal rim. The
central bearing plate is attached to thecentral bearing plate is attached to the
mandibular occlusal rim or trial basedmandibular occlusal rim or trial based
denture base.denture base.
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95. The central bearing screw is firstThe central bearing screw is first
adjusted so it is obviously too long i.eadjusted so it is obviously too long i.e
the mouth is opened beyond thethe mouth is opened beyond the
physiologic rest position. Then inphysiologic rest position. Then in
progressive steps, the screw is adjustedprogressive steps, the screw is adjusted
downwards until the patient indicatesdownwards until the patient indicates
that the jaws are closing to far.that the jaws are closing to far.
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96. The procedure is repeated in theThe procedure is repeated in the
opposite direction until the patient feelsopposite direction until the patient feels
that the length is about right, thethat the length is about right, the
adjustments are reversed alternativelyadjustments are reversed alternatively
until the height of contact feels right.until the height of contact feels right.
Patient participation in the decision toPatient participation in the decision to
establish a vertical dimension record isestablish a vertical dimension record is
very important.very important.
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97. Disadvantage:Disadvantage:
This method cannot be used in senileThis method cannot be used in senile
patients and in those patients whopatients and in those patients who
have impaired neuromuscularhave impaired neuromuscular
perception.perception.
The problem with this method relates toThe problem with this method relates to
the presence of foreign objects in thethe presence of foreign objects in the
palate and tongue space.palate and tongue space.
The final determination must be madeThe final determination must be made
at the try in after the teeth are inat the try in after the teeth are in
position.position.
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99. Bio feed back using electromyography:Bio feed back using electromyography:
Rest position of mandible can beRest position of mandible can be
determined by means ofdetermined by means of
electromyography which would recordelectromyography which would record
the minimal activity of the muscles.the minimal activity of the muscles.
Electrodes can be placed on one orElectrodes can be placed on one or
more muscles of mastication tomore muscles of mastication to
demonstrate their activation potentialdemonstrate their activation potential
in the form of visual and audio signs,in the form of visual and audio signs,
which are fed back to the patient, towhich are fed back to the patient, to
attain a mandibular position showing nilattain a mandibular position showing nil
or minimum EMG activity.or minimum EMG activity.www.indiandentalacademy.com
100. Disadvantages:Disadvantages:
The equipment is too expensiveThe equipment is too expensive
The operate should have considerableThe operate should have considerable
knowledge, skill and experienceknowledge, skill and experience
The patient should be capable ofThe patient should be capable of
correlating the visual signs to thecorrelating the visual signs to the
correct mandibular position.correct mandibular position.
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101. Tests to aid in confirming the correctTests to aid in confirming the correct
vertical relation:vertical relation:
Judgment of overall facial supportJudgment of overall facial support
Visual observation of space betweenVisual observation of space between
the rims when the jaws are at restthe rims when the jaws are at rest
Measurement between the dots on theMeasurement between the dots on the
face when the jaws are at rest andface when the jaws are at rest and
when the occlusal rims are in contactwhen the occlusal rims are in contact
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102. Observation made when the sibilantObservation made when the sibilant
containing words are pronounced, tocontaining words are pronounced, to
ensure that the occlusal rims comeensure that the occlusal rims come
close together but do not contact.close together but do not contact.
Patient can be asked to pronouncePatient can be asked to pronounce
words like Emma,Mississippi,forty fivewords like Emma,Mississippi,forty five
and thirty three for evaluation.and thirty three for evaluation.
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103. Effects of increased verticalEffects of increased vertical
dimension:dimension:
It is very important to remember that asIt is very important to remember that as
mentioned by Mehrson and Tench thementioned by Mehrson and Tench the
tone of the muscles may be increasedtone of the muscles may be increased
within physiologic limits but thewithin physiologic limits but the
functional length cannot be increasedfunctional length cannot be increased
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104. EffectsEffects
Discomfort to the patientDiscomfort to the patient
Trauma and pain to the basal seatTrauma and pain to the basal seat
areasareas
The jarring effect of teeth coming intoThe jarring effect of teeth coming into
contact sooner than expected may notcontact sooner than expected may not
only cause discomfort but in mostonly cause discomfort but in most
cases it will also cause pain owing tocases it will also cause pain owing to
the bruising of the mucosa by thesethe bruising of the mucosa by these
sudden and frequent blows.sudden and frequent blows.
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105. Loss of freeway space: This will result inLoss of freeway space: This will result in
fatigue of any one or group of muscle offatigue of any one or group of muscle of
mastication. In turn, it will result inmastication. In turn, it will result in
annoyance from the inability to findannoyance from the inability to find
comfortable resting position.comfortable resting position.
Clicking sound when the teeth contactClicking sound when the teeth contact
Appearance: The face has an elongatedAppearance: The face has an elongated
appearance. The lips are apart at restappearance. The lips are apart at rest
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107. ConclusionConclusion
No one method of recording or determiningNo one method of recording or determining
the jaw relations can be accepted as beingthe jaw relations can be accepted as being
valid for all patients, there fore it is desirablevalid for all patients, there fore it is desirable
to use several methods and confirm theto use several methods and confirm the
results. More over the components of theresults. More over the components of the
recording procedure include morphologicrecording procedure include morphologic
and physiologic phenomena, the functionaland physiologic phenomena, the functional
activity, psychological and social criteriaactivity, psychological and social criteria
particularly in relation to esthetic decisions.particularly in relation to esthetic decisions.
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108. ReferencesReferences
Boucher’s prosthodontic treatment for edentulousBoucher’s prosthodontic treatment for edentulous
patients – 9patients – 9thth
, 10, 10thth
,11,11thth
edition.edition.
syllabus of complete dentures –Heartwell.syllabus of complete dentures –Heartwell.
Essentials of complete denture prosthodonticsEssentials of complete denture prosthodontics
––Sheldon Winkler.Sheldon Winkler.
Complete denture prosthodonticsComplete denture prosthodontics
–– John J.Sharry.John J.Sharry.
Evaluation diagnosis, and treatment of occlusalEvaluation diagnosis, and treatment of occlusal
problems Peter E Dawson.problems Peter E Dawson.
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109. Speaking method in measuring verticalSpeaking method in measuring vertical
dimension. J.P.D 2001 vol 85 no 5 427-430.dimension. J.P.D 2001 vol 85 no 5 427-430.
Using the neutral zone to obtainUsing the neutral zone to obtain
maxillomandibular relationships.J.P.D 2001 volmaxillomandibular relationships.J.P.D 2001 vol
85 621-3.85 621-3.
Pre extraction records for complete denturePre extraction records for complete denture
fabrication. J.P.D 2004 vol 91 55-8.fabrication. J.P.D 2004 vol 91 55-8.
Physiological jaw relations and oclusion ofPhysiological jaw relations and oclusion of
complete dentures. J.P.D 2004 vol 91 203-5.complete dentures. J.P.D 2004 vol 91 203-5.
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