Factors influencing the interocclusal direct records are:
• Stability of the record base
• Number of reference points used to make the records
• Amount of pressure exerted on the displaceable tissues in the joints
• Amount and equalization of pressure depends on uniform
consistency of the recording material
• Abnormal skeletal jaw relation
• Excessively displaceable tissues
• Abnormal mandibular movements
• These are low-fusing materials.
• These offer little resistance to jaw closure when soft and these stiffen
• These can be used in a patient with poor muscular control.
• These require less time and equipment.
• These harden on the surface first then inside.
• These are technique-sensitive and do not provide uniform resistance
Compound, plaster and zinc oxide eugenol
• These should remain in contact until these harden.
• These normally break before distortion.
• Setting and hardening time can be controlled in case of plaster and
to less extent in zinc oxide paste but cannot be controlled in case of
• These records require longer time to set.
• These can be used when nonanatomic posterior teeth are used.
Tactile or interocclusal record can be made in following two steps:
• Tentative CR is recorded using wax rims attached to stable bases.
• Interocclusal check record is made during try-in stage.
• Maxillary rim is inserted in patient’s mouth and facebow transfer is
• Maxillary cast is mounted on articulator.
• Vertical dimension at rest is established and the mandibular rims
are reduced to allow excess interocclusal distance.
• Recording material is placed in between and the tentative CR record
• The mandibular rim is mounted using this record and teeth are
Interocclusal check record during wax try-in:
• Both maxillary and mandibular trial record bases are inserted in the
• Patient is prevented from occluding by using cotton rolls on both
• Recording material such as Aluwax is placed on the mandibular rim
in the premolar and molar regions and the patient is allowed to
slowly close and stop just short of making tooth contact.
• Once the record is set, the maxillary and mandibular trial dentures
are placed on the articulator and the record is seated on the
• If the tentative relation is correct, then the condylar elements will
rest against the centric stops in the same position as the cast were
• If not, then the record is incorrect and is to be repeated.
• Occlusal indicator wax can also be used instead of the Aluwax as
interocclusal check record, especially when nonanatomic posterior
• V-shaped notch is made on the maxillary occlusal rim.
• Nick is made anterior to the notch on the maxillary rim.
• A trough is created on the mandibular rim from premolar region to
• Petroleum jelly is applied in the nick and notch areas.
• Aluwax or zinc oxide paste is placed in the trough in the
mandibular rim and the patient is guided into centric position.
• Occlusal rims along with the recording material are removed.
• Any excess material is trimmed and casts are mounted on
articulator using this record.
• Occlusal rims are sealed with staple pins in centric position.
• This method should not be used, as the CR record cannot be
• T.E.J. Shanahan (1955) used physiologic approach to record CR
position. He advocated cones of soft wax to be placed on the
mandibular occlusal rims and the patient was asked to repeatedly
swallow. According to him, during swallowing, the tongue forced
the mandible to be in CR position (Fig. 6-16).
FIGURE 6-16 Shanahan swallowing method.
• Jacob W. Greene described ‘pressometer’ to check equalization of
pressure in recording CR. It consisted of two celluloid strips which
were placed between the maxillary and the mandibular bite rims
bilaterally. If the pressures were unequal, the rims would hold one
strip while the other could be removed.
Eccentric jaw relation is defined as ‘any relationship between the jaws
other than the centric relation’. (GPT 4th Ed)
Eccentric records should include the protrusive and the right and
left lateral records. The purpose of the eccentric relation record is to
adjust the horizontal and lateral condylar inclinations on the
articulator. These adjustments are necessary to achieve balanced
occlusion in the complete dentures. These records can be made by
functional, graphic or tactile methods within the functional range. The
methods of recording eccentric records are similar to the methods
used to record the CR position.
Extraoral tracing with a central bearing device has several
advantages over other techniques, if the recording devices are
• Once the mandibular cast is mounted on the articulator in CR, the
recording devices are placed back in the patient’s mouth.
• Distance of 5–6 mm is measured from the apex of the tracing on the
protrusive path and is marked.
• Patient is instructed to protrude the jaw till the stylus rests on the
• Quick setting plaster is injected in between the rims and is allowed
• Hardened cast is removed from the mouth.
• Horizontal condylar adjustments are freed on the articulator by
• The incisal guide pin is raised about ½ inch from the incisal guide
• The record bases are seated on the cast, and hardened cast is placed
• Accurate seating of both the condyles is ensured and locknuts are
• The right and left calibrations of the horizontal condylar guidance
• For the lateral records, two additional records are made, one on the
right lateral and the other on the left lateral position in similar
manner as described above for protrusive.
• The articulator is adjusted to each of this lateral record.
• Also, the protrusive relation record can be made by using layers of
• During the wax try-in, the patient is instructed to protrude the
lower jaw approximately 5–6 mm.
• Once the patient has learned this position, layers of soft wax are
placed on the posterior and anterior teeth of the lower trial denture.
• Patient is asked to protrude the jaw to a distance of 5–6 mm with the
• Wax is allowed to harden and then removed.
• Wax record is inspected for even contact.
• This record is used to adjust the horizontal condylar guidance on
Important consideration during eccentric jaw relations are as follows:
• Condylar path cannot be controlled or altered by the clinician.
• Condyles always follow the contour of the bony fossae and never
• Articulators having straight slot for condylar elements travel are not
suitable for eccentric records.
• Articulators should accept the lateral records which provide other
• Articulators which can record the individual condylar path using
pantographic tracings provide information in three planes.
• Camper’s line is the line joining the inferior border of the ala of the
nose to the superior border of the tragus. Ideally, the Camper’s
plane is considered to be parallel to the occlusal plane.
• Christensen’s phenomenon is the space that occurs between the
occlusal surfaces during mandibular protrusion.
• Central bearing device was first described by Alfred Gysi in 1910.
• Interocclusal distance or freeway space is 2–4 mm which is
observed in the premolar region in class I cases. In class II, it is
greater than 4 mm and in class III, it is less than or equal to 1 mm.
• Gothic arch tracing is a device which produces a tracing resembling
the arrowhead or Gothic arch during the mandibular movements.
• Increased vertical dimension leads to trauma to the tissues, pain in
the TMJ, clicking sound of the dentures, increased facial height,
tense facial muscles and difficulty in speech.
• Reduced vertical dimension results in reduced function of the
muscles with loss of muscle tone, creases at the corner of the mouth,
trauma to the TMJ, decreased facial height, lax facial muscles with
• Vertical dimension influences the aesthetics and mechanics of the
denture and if incorrect may produce possible disturbances in the
• M.E. Niswonger (1934) called the rest position as neutral position and
Evolution of Anterior Teeth Selection, 124
Selection of Anterior Teeth, 125
Size of the Maxillary Arch, 126
Distance between the Canine Eminences, 127
Contour of Residual Ridge, 127
Vertical Distance between the Ridges, 127
Composition of Material of Anterior Teeth, 130
Posterior Teeth Selection, 133
Size of the Posterior Teeth, 134
Form of the Posterior Teeth, 135
Colour of the Posterior Teeth, 136
Material of the Posterior Teeth, 136
Arrangement of the Anterior Teeth, 136
Relationship of Anterior Teeth with the Incisive
Relationship of Anterior Teeth with the Soft
Horizontal Relation with Residual Ridges, 137
Vertical Positions of the Maxillary Anterior
Arrangement of the Posterior Teeth, 138
Horizontal Positioning of the Posterior
Vertical Positioning of the Posterior Teeth, 139
Buccolingual Positioning of the Posterior
Principles of Arranging Teeth, 140
Mandibular Anterior teeth, 141
Maxillary Posterior Teeth, 141
Mandibular Posterior Teeth, 142
Role of Phonetics in Complete Denture
Prosthetic Considerations, 146
Optimum aesthetics in complete denture construction is achieved by
arranging teeth in their natural position and according to the patient’s
aesthetic and functional requirement. Complete dentures are
aesthetically pleasing when teeth and denture bases are in harmony
with the facial musculature, facial profile and colour of eyes, and skin.
Denture aesthetics is defined as ‘the ef ect produced by a dental prosthesis
that af ects the beauty and attractiveness of the person’. (GPT 8th Ed)
According to S. Winkler, aesthetics in complete denture
prosthodontics is affected by the following three factors:
• The clinician should have proper knowledge of the anatomical
structures, facial musculature and normal facial appearance.
• The clinician should understand the cause and effect relationship.
• If the labial flange is made too bulbous, it will push the lips
outwards giving them an artificial appearance or vice versa.
• Facial wrinkles tend to reduce by increasing the vertical dimension
• But excessive increase in vertical dimension leads to patient
discomfort, clicking sound during function and compromised
• Also, the placement of maxillary and mandibular teeth affects
speech which is dependent on the interocclusal distance.
• The artificial teeth should be arranged at the position which was
once occupied by the natural teeth.
• The teeth should be placed such that forces from the cheeks and lips
are balanced by the forces from the tongue. This area where forces
are balanced is called the neutral zone.
• Placing the teeth in neutral zone will enhance the stability of the
• A patient’s perception of his/her appearance plays an important role
• A patient with a positive self-image will have a broad smile,
whereas a patient with a poor self-image will have a tight-lipped
• Camper’s plane is often considered as the psychological plane of
• Therefore, plane of orientation established by the clinician
determines the psychological state of the patient to some extent.
Pre-extraction guides are an important aid in selecting teeth,
especially the anterior teeth. Various pre-extraction guides used are as
It is defined as ‘life size reproduction of a part or parts of the oral cavity
and/or facial structures for the purpose of study and treatment planning’.
• It is the most reliable aid in selecting and arranging anterior teeth.
• Anterior teeth can be selected by determining the form and size of
• Usually, the patient accepts the shape and form of the teeth similar
• Past photograph which shows the anterior teeth or at least the
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