Occlusal trauma can lead to periodontal damage over time. Specifically, primary occlusal trauma can cause horizontal bone loss around teeth. Once occlusal trauma is eliminated, even in the presence of inflammation, the most likely result is a reduction in tooth mobility as the periodontal ligament space decreases in width and overall bone volume increases. A custom incisal guide table is required for a patient with mutually protected occlusion who is receiving a fixed partial denture replacing teeth 1.1-1.3.
1. 2013
Pg 353 #8
A removable partial denture rest should be placed on the lingual surface of a
canine rather than on the incisal surface because
A. less leverage is exerted against the tooth by the rest.
B. the enamel is thicker on the lingual surface
C. visibility and access are better.
D. the cingulum of the canine provides a natural recess that does not need to be
prepared.
Pag 156 Mcraken’s Removable partial Prosthodontics
2. 2013
Pg 354 # 5
Placement of yellow external stain on a porcelain crown will increase chroma and
A. increase the value.
B. decrease the value.
C. increase the hue.
D. decrease the hue
The three characteristics of color are (1) hue, (2) chroma, and (3) value.
Hue is that quality that distinguishes one color from another. It is the name of a
color, such as red, blue, or yellow. Hue may be a primary color or a combination of
colours
Chroma is the saturation, intensity, or strength of a hue. For example, a red and a pink
may be of the same hue. The red has a high chroma, while the pink, which is actually a
weak red, has a low chroma.
Value, or brightness, is the relative amount of lightness or darkness in a hue. Value is
the most important color characteristic in shade matching. If it is not possible to achieve
a close match with a shade guide, a lighter shade should be selected because it can be
stained more easily to a lower value. It is impossible to stain a tooth to obtain a lighter
shade (higher value) without producing opacity. If major changes are attempted in the
hue or chroma, there will be an accompanying decrease in value
For example A 60 year old patient, compared to a 25years old is most likely to have teeth
With a color that is lower in value and higher in chroma
3. Pg 354 # 9
To achieve optimum strength and esthetics, a metal ceramic restoration with a porcelain
butt joint margin should really have a
A. 0.8 – 1.0mm shoulder reduction
B. 0.8 – 1.0mm incisal reduction. (2mm Incisal reducution n Posterior teeth is 1.5mm)
C. cavosurface margin. (C.S 90 provide better suport for ceramic crown)
D. finish line that is 2mm subgingival
The cavosurface angle is 90 degrees, and shoulder width is only slightly lessened by the
rounded internal angle. Stress concentration is less in the tooth structure than with a
classic shoulder, and support for ceramic restoration walls is good. Destruction of tooth
structure required for this configuration is not significantly less than that
required for a classic shoulder, however.
Porcelain labial margin requires proper support for the porcelain. A shoulder 90ºcavo
surface angle is recommeded
Shillinburg Pag 132
4. Pg 358 #4
Which of the following would require a custom incisal guide table for a patient
with mutually protected occlusion?
A. A fixed partial denture from tooth 3.5-3.7.
B. An all ceramic crown on tooth 4.7.
C. A fixed partial denture from tooth 1.1-1.3.
D. A single ceramometal crown on tooth 1.4.
5. 2013 From 350-372
Pag 359 #2
After the elimination of occlusal trauma, even in the presence of inflammation, which of
the following is most likely to result?
A. Reduction in tooth mobility.
B. Regeneration of the periodontal ligament
C. Restoration of lost alveolar bone.
D. Gain of clinical attachment
For these reasons when treating periodontal patients with occlusal issues the first
aim of therapy should be directed at alleviating plaque-induced inflammation.
Once this has been accomplished efforts can then be directed at adjusting the
occlusion. This may result in a decrease in mobility, decrease in the width of the
periodontal ligament space, increase in overall bone volume. Finally, in cases
planned for regenerative therapy, consideration to stabilizing mobile teeth should
also be given prior to surgical intervention.
Naval Postgraduate Dental School
National Naval Dental Center
8901 Wisconsin Ave
6. Pag 360 #2
Overadjustment of a wrought wire denture clasp can lead to fracture because of a/an
A. increase in modulus of elasticity.
B. decrease in ductility due to strain hardening.
C. decrease in the yield strength
D. increase in fracture toughness
Fracture toughness is the ability to deform plastically without
fracture
and is proportional to energy consumed in plastic deformation.
Cracks
or flaws, arising naturally or developing over time, cause
weakening
such that fracture may occur at stresses below the yield
stress, the flaw
acting as a stress riser.
Dental materials at glance pag 5
7. Pag 360 #9
A conical pontic replacing a mandibular first molar should be designed so that
A. it seals the mucogingival fold.
B. it has open gingival embrasures.
C. the porcelain to metal junction is on its gingival surface.
D. the gingival surface is concave buccolingually
The conical pontic is rounded and cleanable, but the tip
is small in relation to the overall size of the pontic. It is
well suited for use on a thin mandibular ridge (Fig 26-15,
A). However, when used with a broad, flat ridge, the
resulting large triangular embrasure spaces around the
tissue contact have a tendency to collect debris
Fundamental and Fixed Prosthodontics pag 481
Shillinburg
8. Pag 361 #2
A reciprocal clasp arm on a removable partial denture will provide
A. support.
B. indirect retention.
C. stabilization.
D. direct retention
Reciprocation to prevent transient horizontal forces
that may be detrimental to abutment stability is
most needed when the restoration is placed or
when a dislodging force is applied.
Mc Cracken RPD pag 254
9. Pg368#2
The major connector of a removable partial denture should be designed to
A. rigidly connect the denture components
B. act as a stress-breaker Clasp retainers on abutment teeth adjacent to distal
extension bases should be designed so that
they will avoid direct transmission of tipping and
rotational forces to the abutment. In effect, they
must act as stress-breakers either by their design
or by their construction.
C. dissipate vertical forces
D. distribute forces to the soft tissues
A rigid major connector will limit
movement possibilities by acting as a counteracting
lever. This phenomenon is referred to as cross-arch
stability. Cross-arch stability becomes more important
in situations associated with a high potential for
greater prosthesis movement (i. e., distal extension
Mc Cracken RPD pag 42
10. Pag 359 #1
Primary occlusal trauma can cause
A. gingival recession.
B. furcation involvement.
C. horizontal bone loss
D. tooth sensitivity.