MDS PREP
When loads are placed on the abutment tooth, all of the following result except
1) Widening if the periodontal ligament
2) Increase in the density of the cortical plates
3) Increase in the trabeculation of the alveolar bone
4) None of the above
Prosthodontics
Answer: 4
Effects of loading on the abutment tooth and the surrounding structures.
Widening of the periodontal ligament: When loads are
applied to a tooth, the periodontal ligament (PDL) experiences stress. This
can lead to a mild widening of the PDL space due to the mechanical loading
and adaptive responses of the tissues involved. Thus, this statement is
true.
Increase in the density of the cortical plates: When
there is functional loading, the cortical bone surrounding the teeth can
adapt by increasing in density (a process known as bone remodeling).
Increased loads can stimulate bone formation, leading to denser cortical
plates. This statement is also true.
Increase in the trabeculation of the alveolar bone:
Similar to the cortical plates, the trabecular (or cancellous) bone also
adapts to loads through a process of remodeling, often leading to increased
trabeculation during functional loading. This means denser and more
organized bone structure in response to the applied forces, which is true as
well.
None of the above: Given that all the previous
statements can be considered true in the context of what happens when loads
are applied to the abutment tooth, the option "None of the above" suggests
that all of the listed outcomes can occur with loading on the abutment
tooth, making option 4 the correct choice.
In summary, when loads are placed on the abutment tooth, all the mentioned
effects (widening of the periodontal ligament, increase in the density of the
cortical plates, and increase in the trabeculation of the alveolar bone) are
valid responses to mechanical stress. Therefore, the answer 4 (None of the
above) is correct because there are no false statements among the listed
outcomes.
The mean denture bearing area in the edentulous mandible is approximately
1. 12.25 cm square
2. 16.25 cm square
3. 18.12 cm square
4. 20.25 cm square
Prosthodontics
Answer: 1
The mean denture bearing area in the edentulous mandible is approximately 12.25 cm square.
The range of motion, as measured in millimeters, is least for the
1. pure hinge like opening and closing movement
2. protrusive movement
3. left lateral movement
4. Bennet movement
Prosthodontics
Answer: 4
Explanation:
Pure hinge-like opening and closing movement: The range of pure rotation in
the temporomandibular joint (TMJ) was determined to be up to 1520 mm in the
1960s. However, recent research suggests that pure rotational movement may not
occur.
Protrusive movement: The normal range of motion for protrusive movement is
812 mm.
Left lateral movement: The normal range of motion for left lateral movement
is 812 mm. The normal range of motion for mouth opening is 3560 mm.
The average immediate Bennett shift was found to be 1.05 mm on the left
side and 1.12 mm on the right side when firm guidance was used.
Excessive application of pressure on the posterior portion of the occlusal rim during jaw relations results in
1. Anterior open bite
2. Posterior open bite
3. Anterior deep bite
4. Unbalanced occlusion
Prosthodontics
Answer: 1
Excessive application of pressure on the posterior portion of the occlusal rim during jaw relations results in an anterior open bite.
What is the significance of the path of insertion in removable
partial dentures?
1) It is the path followed by the denture from first contact until fully
seated
2) It indicates the direction of tooth extraction
3) It determines the color of the denture
4) It measures the size of the denture
Prosthodontics
Answer: 1
The path of insertion is crucial as it describes the trajectory the denture takes during placement, which is essential for ensuring proper fit and function.
When acrylic resin is packed in the sandy stage, it may result in
1) Open bite
2) Porosity
3) Increased strength
4) All of the above
Prosthodontics
Answer: 2
Packing acrylic resin in the sandy stage, which refers to a stage where the material is not fully polymerized and has a grainy texture, can lead to porosity in the final product. This occurs because the incomplete packing can trap air bubbles, resulting in a porous structure that compromises the strength and integrity of the restoration.
Uncontrolled diabetes poses a problem to prosthodontist as
1. More bone resorption
2. Increased salivary flow
3. Less bone resorption
4. Less tissue laxity
Prosthodontics
Answer: 1
Uncontrolled diabetes poses a problem to the prosthodontist as it leads to more bone resorption.
Which dental surveyor is known for its simplicity and durability?
1) Jelenko surveyor
2) Ney surveyor
3) Williams surveyor
4) Highriser RPD surveyor
Prosthodontics
Answer: 2
The Ney surveyor is widely recognized for its simplicity and durability, making it a popular choice among dental professionals.