Chapter 1

Question 1

What is the functional cusps of each arch?

Answer 1

Maxillary: palatal
Mandibular: buccal

Question 2

When the mandibular lingual cusps are in the maxillary fossa, and the maxillary buccal cusps are in the mandibular fossa, what is this called?

Answer 2

Buccal i.e. cross bite.

Question 3

In individual supporting cusps, which cusp of maxillary molar seats in central fossa of mandibular molar? And which mandibular molar cusp seats in maxillary central fossa?

Answer 3

The MP cusp of maxillary molar teeth normally seated in central fossa of the mandibular molars
The DB cusp of mandibular molar teeth seat in central fossa of maxillary molars.

Question 4

Where do the palatal cusps of the maxillary bicuspids contact on mandibular teeth?

Answer 4

Contact the marginal ridges of mandibular bicuspids and 1st molar

Question 5

In ICP of intact and unworn teeth, where does the supporting cusp contact in the adjacent fossa? (3 points of contact- name all)

Answer 5

The contact is not at the very tip of the supporting cusp, nor at the deepest part of the fossa; They contact the opposing inclines leading to the fossae, ideally with buccal and lingual contact for each cusp.
The supporting cusps have at least one mesial or distal contact with opposing marginal, triangular, transverse of oblique ridges.

Question 6

What is the term that describes the precise firm position of the supporting cusp in closure/occlusion?

Answer 6

Tripodisation or tripodism (at least three contacts).

Question 7

What are the actual points found in tripodisation called?

Answer 7

Centric stops or holding contacts as they hold teeth in stable position.

Question 8

Describe centric relation

Answer 8

Position of the mandible to the maxilla, with the intra-articular disc in place, when the head of the condyle is against the most superior part of the distal facing incline of the glenoid fossa.

Question 9

What is the Working side, and the non-working side?

Answer 9

WS: the side to which the mandible is moving
NWS: is the side from which the mandible is moving away from.

Question 10

What movement(s) does the WS condyle do? What is the term for this name?

Answer 10

The WS condyle moves laterally. Immediate non-progressive lateral movement i.e. immediate side shift (ISS) or Bennet movement.

Question 11

What movement(s) does the NWS condyle do? What is the movement called?

Answer 11

Forward, medially and downwards. It is called the Bennet angle

Question 12

What is the bennet angle and the condylar angle?

Answer 12

The direction of movement of the NWS condyle forwards, downwards and medially. It is defined against the horizontal plane by the conylar angle and the vertical plane by the Bennet angle.

Question 13

What is the Bennet movement? What else can it be called?

Answer 13

Bennet movement is the bodily movement of the working side condylar head outwards (laterally) during lateral excursions. It is also known as Immediate side shift or Immediate non-progressive side shift. (Image 1)

Question 14

What is the average movement in mm in the Bennet movement?

Answer 14

In average normal person the shift is 1.5mm towards the lateral position corresponding to an end to end position of the cuspids on the working.

Question 15

Why does the Bennet movement happen?

Answer 15

It is the effect of the forward, medial and downward movement of the NWS condyle during lateral excursion i.e. Because of the Bennet angle.

Question 16

What is the bennet angle

Answer 16

The angle formed by the medial movement of the NWS to the vertical plane.

Question 17

If the bennet movement is absent, does the bennet angle still exist?

Answer 17

The bennet angle exists even in the absence of bennet movement.

Question 18

What is the condylar angle?

Answer 18

The angle formed against the horizontal plane by the downward movement of the condyle(s) during translation down the distal face of the articular eminence, as during opening of the mandible, or during lateral excursion when the NWS condyle move downwards in its forwards downwards and medial movement.

Question 19

The condylar angle is measurable at which condyle?

Answer 19

Both condyles- it is the angle formed against the horizontal plane by the path the condyles follow when it travels down the distal face of the articular eminence during the translation phase of the mouth opening. It is also measured at the non working side condyle during its DFM in lateral excursion.

Question 20

What is the average condylar angle range?

Answer 20

Range from 22-65 degrees. An average value of 30 degrees is generally used on an average value articulator.