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Surveying maxillary cast
Mark the ideal survey lines
Tooth modifications
1.
2.
3.
Contour modifications
Guide planes
Rest seats
LINGUAL
LABIAL
DISTAL VIEW OF DISTAL & LINGUAL
GUIDING PLANE ON A CUSPID.
LINGUAL
BUCCAL
DISTAL VIEW OF LINGUAL AND
DISTAL GUIDING PLANES.
MESIAL
DISTAL
LINGUAL VIEW OF DISTAL & LINGUAL
GUIDING PLANES.
Buccal View of Distal
Guiding Plane
DISTAL
MESIAL
RESTS
Prevent vertical movement of
partial into tissue

The term rest designates any component of
the framework that is placed on a tooth. It
must be in a PREPARED REST SEAT. It
limits the movement of the prosthesis in a
gingival direction and transmits forces to the
long axis of the teeth.
 Contact on a tooth surface incline without a
rest seat could result in tooth movement
converting the RPD to an ORTHODONTIC
APPLIANCE.
1o SUPPORT
Rests
 Transmits forces through long axis of
tooth
 Transmits forces through periodontal
ligament
 Stabilizes against rotational forces

Rest seats can be located on the
occlusal and incisal sufaces of a tooth
as well as the cingulum and in some
instances the marginal ridges of
canines.
REST AREA - REST SEAT
1
That portion of the tooth selected and
prepared to receive an occlusal, incisal,
marginal ridge or cingulum / lingual rest.
2
The portion of the tooth structure or of a
restoration in a tooth prepared so it is spoon
shaped on posterior teeth and V, U or hookshaped on some anterior teeth, into which
seats the metallic rest of a removable partial
denture framework.
DESIGN CHARATERISTICS OF
RESTS
1. Large enough to fit a casting to
2. Forms acute angles with minor connectors prevents tooth from moving away from
partial
3. Does not interfere with occlusion
TYPES OF RESTS
1. Occlusal
2. Cingulum
3. Incisal
OCCLUSAL RESTS
Maxillary premolar
Mandibular First Premolar
Occlusal Rests

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
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Rounded triangular shape-”teaspoon”
Approximately one-third width of tooth
Marginal ridge should be lowered to permit
bulk of metal for strength.
Floor of rest apical to marginal ridge.
No sharp edges or line angles.
Angle formed by minor connector and rest
should be less than <ninety degrees.
Definitive rest
CINGULUM
RESTS
Mandibular
Cingulum Rests
Cingulum Rest
-Restoration
-Natural tooth
Cingulum Rests
Most effective on maxillary canines.
 Slightly rounded inverted “V” shape.
 When mandibular canines / incisors are
utilized a rounded ledge at the level of
the cingulum can serve as a rests.
 Care must be taken to avoid enamel
undercuts.

INCISAL
REST
Incisal Rests
Prepared in form of rounded notch at
incisal angle of canine or incisal edge of
incisor.
 Should be approximately 2.5 mm wide
and 1.5 mm deep.
 Notch is beveled both labially and
lingually.

Marginal Ridge Rest
45o
Bonded Resin Cingulum Rest