vi. Oral Biology Flashcards

1
Q

L40: What are the muscles of mastication?

A

The ‘mandibular muscles’:

  • Masseter;
  • Temporalis;
  • Lateral Pterygoid;
  • Medial Pterygoid.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

L40: What is the origin, insertion and action of the masseter?

A

Origin: zygomatic arch
Insertion: lateral surface and angle of the mandible
Action: elevates mandible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

L40: How do you examine the masseter?

A
  • Tender in pts who have a clenching habit;
  • Place one finger intra-orally and the other on the cheek;
  • Is it sore, tender, inflamed?
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

L40: What is the origin, insertion and action of the temporalis?

A

Origin: floor of the temporal fossa
Insertion: coronoid process of the anterior border of ramus
Action: Elevates and retracts mandible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

L40: How do you examine the temporalis?

A
  • Tender in pts who have a clenching habit;
  • Palpate its origin (can’t palpate insertion) by asking the pt to clench together;
  • Is it sore, tender, inflamed?
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

L40: What is the origin, insertion and action of the lateral pterygoid?

A

Origin: from the lateral surface of the lateral pterygoid plate
Insertion: anterior border of the condyle and intra-articular disc (via two independent heads)
Function: protrudes and laterally deviates the mandible and the inferior head functions with the mandibular depressors during openings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

L40: What are the insertions of each belly of the lateral pterygoid?

A

Inferior belly: head of the condyle;

Superior belly: intra-articular disc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

L40: What are typical symptoms of lateral pterygoid problems?

A
  • Click on opening of mouth;
  • Poor opening of mouth;
  • Spasm due to exhaustion of muscle (overnight clenching).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

L40: How are lateral pterygoid issues usually treated?

A
  • Splint;

- Physiotherapy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

L40: The lateral pterygoid is not accessible to palpate so how is this examined?

A
  • Best examines by recording the response to resisted movement (sideways);
  • Palm on top of head and on mandible;
  • Ask pt to move jaw sideways.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

L40: What is the origin, insertion and action of the medial pterygoid?

A

Origin: medial surface of the lateral pterygoid plate (deep head), tuberosity of maxilla (superficial head)
Insertion: medial surface of angle of mandible
Action: elevates and assists in protrusion of the mandible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

L40: Are you able to palpate/ examine the medial pterygoid?

A

No - due to its location and it doesn’t respond well to resistive movement tests (trismus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

L40: Following a LA injection, your pt is unable to open their mouth fully on the following day. Which muscle was hit by the LA?

A

Medial pterygoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

L40: When administering a LA, where should the needle contact and why?

A

The bone, to ensure the correct position within the pterygomandibular triangle (not the soft tissues)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

L40: How many movements does the TMJ involve?

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

L40: What are the 2 movements of the TMJ?

A
  • Rotation (initial opening);

- Translation (wider opening).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

L40: What is the initial opening movement?

A

A hinge movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

L40: What is the secondary movement?

A

Translation, a sliding movement

for wider opening/ protrusive and retrusive movements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

L40: Explain what happens when the mandible protrudes.

A
  • Both condyles leave their fossae;

- Move forward along the articular eminences.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

L40: Explain what happens when the mandible retrudes.

A
  • Leave the eminences;

- Both condyles move back to their fossae;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

L40: What is Posselt’s envelope?

A

A representation of maximum mandibular movement (from border movements of three different planes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

L40: What is the range of typical maximum biting force between molars?

A

200-700N (varies between teeth)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

L40: What factors affect maximum biting force?

A
  • Psychological: Fear of tooth fracture;
  • Muscle mass: bigger muscles, larger forces;
  • Tooth type and position: relative to TMJ, root area (PDL support).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

L40: Why are greatest biting forces achieved between molars?

A

Closest to TMJ and muscles generating the forces, largest occlusal areas too

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

L40: What are the different muscle fibre types and what forces are they responsible for?

A
  • Type I: slow, low forces;

- Type II (sub-types IIA, IIX, IIB): fast, stronger forces.

26
Q

L40: What are the four supra hyoid (above hyoid bone) muscles?

A
  • Digastric;
  • Mylohyoid;
  • Geniohyoid;
  • Stylohyoid.
27
Q

L40: What is a major function of supra hyoid muscles?

A

Jaw depressors

28
Q

L40: What are the four infra hyoid (below hyoid bone/ ‘strap’) muscles?

A
  • Sternohyoid;
  • Omohyoid;
  • Thyrohyoid;
  • Sternothyroid.
29
Q

L40: What do the infra hyoid bones do to ‘fix’ the hyoid bone in place?

A

Contract

30
Q

L40: What do intrinsic tongue muscles do and what are their names?

A
  • Alter shape;
  • Longitudinal;
  • Vertical;
  • Transverse.
31
Q

L40: What do extrinsic tongue muscles do and what are their names?

A
  • Alter shape and position;
  • Genioglossus;
  • Hyoglossus;
  • Palatoglossus;
  • Styloglossus.
32
Q

L40: Which facial muscles help to control a food bolus and prevent spillage?

A
  • Orbicularis Oris;

- Buccinator.

33
Q

L47: What are the three branches of the trigeminal nerve?

A
  • Ophthalmic;
  • Maxillary;
  • Mandibular.
34
Q

L47: Which cranial nerve is the trigeminal nerve?

A

Cranial nerve five (V)

35
Q

L47: What are the cranial nerves?

A
I: Olfactory
II: Optic
III: Oculomotor
IV: Trochlear
V: Trigeminal
VI: Abducens
VII: Facial
VIII: Vestibulocochlear
IX: Glossopharyngeal
X: Vagus
XI: Accessory
XII: Hypoglossal
36
Q

L47: Which branch of the mandibular branch, of the trigeminal nerve, innervates the front of the chin and lower lip?

A

Mental nerve

37
Q

L47: Where does the mental nerve exit the mandible?

A

Mental foramen

38
Q

L47: What is paraesthesia?

A

An abnormal sensation, typically tingling or prickling

39
Q

L47: What is dyaesthesia and what causes it?

A

An abnormal, unpleasant sensation felt when touched due to damage to peripheral nerves

40
Q

L47: What is the afferent (sensory) supply of the gag reflex?

A

IX, glossopharyngeal

41
Q

L47: What is the efferent (motor) supply of the gag reflex?

A

V: Jaw opening
X: Pharyngeal constriction
XII: Tongue thrust

IX and XI also

42
Q

L47: With regards to RPDs, what method can be used to prevent the patient’s gag reflex during its use?

A

Use of a metallic mesh attachment to the base, instead of a post-dam ridge

43
Q

L47: What is Bell’s Palsy?

A

Temporary facial paralysis to one side of the face

44
Q

L47: What are the common causes for Bell’s palsy?

A
  • Infection;
  • Otitis Media;
  • Diabetes;
  • Trauma;
  • Toxins;
  • Infiltration of LA during dental tx.
45
Q

L47: What are the common symptoms for Bell’s Palsy?

A
  • Asymmetrical;
  • Inability to wrinkle brow;
  • Drooping eyelid;
  • Inability to puff cheeks;
  • Drooping mouth.
46
Q

L47: How can LA in dental tx cause Bell’s Palsy?

A

When the injection is given too far distally, the LA penetrates the parotid gland, then diffuses to the facial nerve and effects all five branches

47
Q

L47: What should you do if your patient develops Bell’s Palsy as a result of your tx?

A
  • Reassure them it is temporary;

- Protect their eye with a loose pad to protect the cornea until blinking returns.

48
Q

L47: Which cranial nerve is the facial nerve?

A

Cranial nerve seven (VII)

49
Q

L47: What are the five branches of the facial nerve?

A
  • Temporal (two);
  • Zygomatic (zulus);
  • Buccal (bugged);
  • Mandibular (my);
  • Cervical (cats).
50
Q

L47: What is the benefit or retaining natural tooth roots or stumps with RPD tx?

A
  • For periodontal mechanoreceptors: a better appreciation of food/ more precise mandibular movement;
  • Psychological benefit: retaining own teeth;
  • Gradual transition to a complete denture.
51
Q

L47: What is the lowest threshold for mechanoreceptors?

A

0.5mN

52
Q

L47: What functions do periodontal mechanoreceptors contribute to?

A
  • Direction of applied forces to teeth;
  • Mastication (food consistency);
  • Salivation;
  • Interdental discrimination.
53
Q

L47: What receptors (location) contribute to interdental size discrimination?

A
  • TMJ;
  • Muscles;
  • PDL.
54
Q

L47: What is proprioception?

A

Awareness of position and orientation of body parts

55
Q

L47: What proprioceptors contribute to proprioception?

A
  • Joint;
  • Muscle;
  • PDL.
56
Q

L47: What is dysphagia?

A

Difficulty swallowing

57
Q

L47: What can cause dysphagia?

A
  • Stroke;
  • Brain injury;
  • MS;
  • GORD;
  • Tumours.
58
Q

L47: What are nociceptors?

A

Receptors that detect intense stimuli, usually associated with pain

59
Q

L47: What is the medical term for a loss of smell?

A

Anosmia

60
Q

L47: Why can anosmia effect sense of taste?

A

Smell and taste are strongly interlinked because the sense of smell stimulates salivary glands and saliva contributes to the initial breakdown of food, which you taste