Excess height of the posterior palatal seal

 # Excess height of the posterior palatal seal of a complete maxillary denture will usually result in which of the following?

A. Gagging

B. Increased retention

C. A tingling or tickling sensation

D. Unseating of the denture

The correct answer is D. Unseating of the denture.

Over contouring or excessive beading of the posterior palatal seal causes too much pressure to be exerted on the palatal tissues resulting in the unseating of upper dentures.

The posterior palatal seal is typically placed approximately on the vibrating line between the hard and soft palate and provides a physiologically acceptable tissue pressure within the compressible portion of the soft palate to attain retention and peripheral seal.

Over extending the coverage of seal will cause gaggling and painful swallowing for the part of the patient. 

Flabby maxillary anterior ridge

# Which of the following is associated with a flabby maxillary anterior ridge under a complete denture?

A. Retained mandibular anterior teeth

B. A "V" shaped ridge

C. A "U" shaped ridge

D. A patient with Class Il occlusion

E. Osteoporosis 

The correct answer is A. Retained mandibular anterior teeth.

Combination syndrome is a condition that usually occurs when retained mandibular

anterior teeth opposes a maxillary complete denture.

In combination syndrome, the anterior aspect of upper maxillary ridge becomes highly resorbed and flabby due to the biting force against its natural tooth antagonist.

Since the occlusal force of a natural tooth is stronger than the force of a denture supported by an alveolar ridge, the area under pressure will exhibit higher resorption pattern than the rest of the denture.

Pterygomandibular raphe is a tendon between

# Pterygomandibular raphe is a tendon between which of the following muscles?

A. Masseter and medial pterygoid

B. Anterior belly of the digastric and Buccinator

C. Buccinator and Superior constrictor

D. Buccinator and Masseter

The correct answer is C. Buccinator and Superior constrictor.

Pterygomandibular raphe acts as a tendon between the buccinator and superior Constrictor muscle. It is a landmark used often for the identification of the pterygomandibular space for the administration of an inferior alveolar nerve block.

The injecting needle pierces the buccinator muscle to inject the local anesthetic solution in the pterygomandibular space.

 

Number of lobes in a tooth

 # The minimum number of lobes from which any tooth may develop is:

A. Two

B. Three

C. Four

D. Five

The correct answer is: C. Four.

Tooth development begins with increased cell activity in growth centers in the tooth germ. A growth center (lobe) is an area of the tooth germ where the cells are particularly active. These lobes are primary centers of calcification and are primary sections of formation in the development of the crown of a tooth. They are represented by a cusp on posterior teeth and mamelons and cingula on anterior teeth. They are always separated by developmental grooves, which are very prominent in the posterior teeth and form specific patterns. With anterior teeth, their presence is much less noticeable and these lobes are separated by what are known as developmental depressions.

Summary of number of lobes:

•All anterior teeth: three labial and one lingual (cingulum)

• Premolars: three buccal and one lingual.

Exception: The mandibular second premolar has three buccal and two lingual lobes.

• First molars (maxillary and mandibular): five lobes, represented by five cusps - one lobe for each cusp

•Second molars (maxillary and mandibular): four lobes, one for each cusp

• Third molars: at least four lobes. one for each cusp ***variations arc seen