Following are the examples of indirect retainers EXCEPT:

 # Following are the examples of indirect retainers except:

A. Occlusal rest

B. Auxillary occlusal rest

C. Canine rest

D. Continuous bar retainers and linguoplates

The correct answer is A. Occlusal rest.

Continuous clasp: “A metal bar usually resting on the lingual surface of teeth to aid in their

stabilization and to act as an indirect retainer”-GPT.

Canine rest

• If the mesial marginal ridge of the first premolar is close to the fulcrum line, canine rest is used.

• This design can be modified by placing the minor connector anterior to the canine. The minor connector hooks back into the cingular rest seat. This increases the efficacy of the indirect retainer (due to increase in distance from the fulcrum line).

Types of Indirect Retainers

The most commonly used type of indirect retainer is a rest connected to a minor connector. In some cases indirect retention is obtained without a rest.

Types:

1. Auxiliary occlusal rest

2. Canine extension from the occlusal rest

3. Canine rest

4. Continuous bar retainers and linguoplates

5. Modification areas

6. Rugae support

7. Direct indirect retention

8. Indirect retention from major connectors

Reference: Nallaswamy, 2nd Edition, Page 375

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Main advantage of the palatal plate major connector is:

 # Main advantage of the palatal plate major connector is:

A. Thick metal plate

B. Thin metal plate

C. Surface irregularity of plate

D. Corrugated plate

The correct answer is D>B. 

Advantages:

• Intimate contact with the palatal tissues over a large area provides good retention due to the presence of interfacial surface tension.

• Provides good vertical support.

• Numerous surface corrugations due to very thin metal provide a very natural feel.

Reference: Nallaswamy, 2nd Edition, Page No 331

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Class IV Kennedy classification is:

 # Class IV Kennedy classification is:

A. A single edentulous area located anterior to remaining natural teeth

B. A single edentulous area present anterior to the canine

C. A single edentulous area present bilaterally on both halves of the jaw

D. A single edentulous area crossing the midline located anterior to the remaining natural teeth

The correct answer is D. A single edentulous area crossing the midline located anterior to the remaining natural teeth

Class IV: Single, bilateral edentulous area located anterior to the remaining natural teeth. This is a single edentulous area, which crosses the midline of the arch, with remaining teeth present only posterior to it. 

Reference: Nallaswamy, 2nd edition, Page no: 272

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Main purpose of tilting the cast in surveying is to:

 # The main purpose of tilting the cast in surveying is to:

A. Locate the undercuts

B. Locate the line of contour

C. Provide the most desirable path of placement

D. Aid in designing

The correct answer is C. Provide the most desirable path of placement.

Tilting the Cast and Altering the Path of Insertion

Some areas of the tooth may form an undercut only when viewed in a different angle. In such cases, the cast can be tilted on a surveyor so that the path of insertion of the denture is altered and the undercuts are present in relation to the new path of insertion.

The cast can be tilted only to a maximum of 10°, beyond which it is not advisable because the patient will require excessive mouth opening for insertion and removal. Generally, tilting the cast to obtain a retentive undercut is the least sorted procedure and is not advisable in the presence of other alternatives.

Ref: Nallaswamy, 2nd Edition Page No: 402

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