Management of Temporomandibular Disorders and Occlusion - E-Book: Chapter 4: Mechanics of Mandibular Movement Flashcards

What two types of movement occur in the TMJ?

Rotational moment of mandible the occurs within the (...) cavity of the joint between the superior surface of the (...) and the inferior surface of the (...).

What three planes can rotational movement of the mandible can occur in?

In each the horizontal, frontal, and sagittal planes, rotational movement of the mandible occurs around a point, called the (...).

Mandibular movement around the horizontal axis is referred to as a (...) movement, and the axis around which it occurs is referred to as the (...).

When the condyles are in their most superior position in the articular fossae and the movement of the mandible is purely rotatational, the axis around which movement occurs is called the (...).

Mandibular movement around the frontal axis occurs when one condyle moves (...), while the vertical axis of the opposite condyle remains in the (...).

Mandibular movement around the sagittal axis occurs when one condyle moves (...) while the vertical axis of the opposite condyle remains in the (...).

Translational movement of mandible the occurs within the (...) cavity of the joint between the superior surface of the (...) and the inferior surface of the (...).

When the mandible moves through the outer range of motion, reproducible describable limits result, which are called (...).

What are the four components of mandibular motion in the sagittal plane?

The range of posterior and anterior border movements is determined primarily by (...); the superior border movements are determined by the (...).

Posterior opening border movements in the sagittal plane occur as two-stage hinging movements. In the first stage, the condyles are in centric relation, and (...) movement occurs until the anterior teeth are (...) mm mm apart.

Which ligament limit rotational movement of the mandible?

Posterior opening border movements in the sagittal plane occur as two-stage hinging movements. In the second stage, the TM ligaments tighten, and the condyle is (...) as the mouth rotates open to its maximum limit of (...) mm.

Which ligament limits maximum opening of the mandible?

With the mandible maximally opened, closure accompanied by contraction of the (...) will generate the anterior closing border movement and tightening of the (...) produces a posterior movement of the condyles.

Which ligament limits the posterior border movement?

Whereas the border movements previously discussed are limited by (...), the superior contact border movement is determined by the characteristics of the (...).

The precise delineation of the superior contact border depends on the:

1. the amount of variation between (...),
2. the steepness of the (...) of the posterior teeth,
3. the amount of (...) of the anterior teeth,
4. the (...) of the maxillary anterior teeth, and
5. the general (...) relationships of the teeth.

The initial tooth contact in (...) occurs between the mesial inclines of a maxillary tooth and the distal inclines of a mandibular tooth.

If muscular force is applied to the mandible in terminal hinge closure, a superoanterior movement or shift will result until the (...) is reached.

The slide from CR to ICP is present in approximately 90% of the population, and the average distance is (...) mm.

When the mandible is protruded from maximum intercuspation, contact between the incisal edges of the mandibular anterior teeth and the lingual inclines of the maxillary anterior teeth results in an (...) movement of the mandible.

As maxillary and mandibular anterior teeth enter an edge-to-edge relationship in protrusion, the the mandible follows a (...) pathway of movement, which continues until the mandibular incisal edges pass beyond the maxillary incisal edges.

Once the mandibular incisal edges pass beyond the maxillary incisal edges in protrusion, the mandible moves in a (...) direction until the posterior teeth contact.

Once the posterior teeth contact in protrusion, their occlusal surfaces dictate the remaining pathway to the maximum protrusive movement, which joins with the most superior position of the (...) border movement.

How is the description of the superior contact border movement is altered when a person has no discrepancy between CR and maximum intercuspation?

(...) movements occur during activity of the mandible. They usually take place within the border movements and therefore are considered free movements.

Most functional activities require maximum intercuspation and therefore typically begin at and below the ICP. When the mandible is at rest, it is found to be located approximately (...) mm below ICP. This position has been called the (...).

If the chewing stroke is examined in the sagittal plane, the movement will be seen to begin and end at the (...) potision.

With the head upright the teeth are elevated directly into (...) from the postural position.

With the head raised 45°, the postural position of the mandible is shifted (...), thus when the teeth occlude, contacts occur (...) to the intercuspal position.

With the head lowered 30°, the postural position of the mandible is shifted (...), thus when the teeth occlude, contacts occur (...) to the intercuspal position.

It has been stated that the normal head position during eating is with the face directed downward 30°. This is referred to as the (...).

A (...) is used to record the mandibular border movements in the horizontal plane. As the mandible moves, the stylus attached to the mandibular teeth generates a pathway on the recording table attached to the maxillary teeth.

What are the four components of mandibular motion in the horizontal plane?

With the condyles in the CR position, contraction of the right inferior lateral pterygoid will cause the right condyle to move (...). If the left condyle remains situated in CR, this will result in the (...) border movement.

During the left border movement, the right condyle is called the (...) condyle and the left condyle is called the (...) condyle.

With the mandible in the left lateral border position, contraction of the left inferior lateral pterygoid muscle along with continued contraction of the right inferior lateral pterygoid muscle will cause the left condyle to move (...), producing the (...) border movement.

With the condyles in the CR position, contraction of the left inferior lateral pterygoid will cause the left condyle to move (...). If the right condyle remains situated in CR, this will result in the (...) border movement.

During the right border movement, the right condyle is called the (...) condyle and the left condyle is called the (...) condyle.

With the mandible in the right lateral border position, contraction of the right inferior lateral pterygoid muscle along with continued contraction of the left inferior lateral pterygoid muscle will cause the right condyle to move (...), producing the (...) border movement.

As mandibular opening increases, the size of the tracings generated by horizontal border movements become successively (...).

The exact position of the mandible during chewing is dictated by the existing (...).

What are the four components of mandibular motion in the frontal plane?

With the mandible in maximum intercuspation, a lateral movement is made to the left. A recording device will disclose an (...) path being generated, which forms the (...) border movement.

The precise nature of the left and right superior border movements in the frontal plane are primarily determined by (...); of secondary influence are the (...).

From the maximum left lateral superior border position, an opening movement of the mandible produces a (...) path. As maximum opening is approached, ligaments tighten and produce a (...) directed movement.

With the mandible in maximum intercuspation, a lateral movement is made to the left. A recording device will disclose an (...) path being generated, which forms the (...) border movement.

From the maximum right lateral superior border position, an opening movement of the mandible produces a (...) path. As maximum opening is approached, ligaments tighten and produce a (...) directed movement.

As in the other planes, functional movements in the frontal plane begin and end at the (...) position.

By combining mandibular border movements in the three planes (sagittal, horizontal, and frontal), a three-dimensional (...) is produced, that represents the maximum range of movement of the mandible