Occlusion 2

Question 1

In what 2 stated can you exmaine the occlusion of a patient?

Answer 1

• static
• dynamic

Question 2

When marking tooth contacts what should you use?

Answer 2

2 diff colours of articulating paper (one colour for static occlusion and one for dynaminc)

Question 3

When should you mark tooth contacts?

Answer 3

Before:

• Preparing a tooth
• Removing a restoration

After:

• Placement of a crown
• Placement of a restoration

Question 4

Why do you want to mark tooth contacts before preparing a tooth?

Answer 4

• You want to look and see if your work will interfere with any occlusal contacts

Question 5

In terms of changing occlusal contacts, you want to check them beforehand and then what would you decide?

Answer 5

If the occlusal scheme is good then would conform to this occlusion (try recreate it)

Question 6

What can be assessed in the static occlusion?

Answer 6

• Incisor Relationship
• Molar relationship
• Overjet/Overbite
• Cross bites
• Open bites
• Individual tooth contacts
• RCP – ICP slide (freedom in centric)

Question 7

What is the definition of a functional cusp in ICP?

Answer 7

Cusps that occlude with the opposing teeth in the intercuspal position

Question 8

What are the functional cusps in a dentition?

Answer 8

• Are the palatal cusps of the upper posterior teeth and the buccal cusps of the lower posterior teeth

Question 9

What is the definition of non-functional cusps in ICP?

Answer 9

• Cusps that do not occlude with the opposing teeth in the intercuspal position

Question 10

What cusps are non-functional cusps?

Answer 10

• Are buccal cusps of the upper posterior teeth and the lingual cusps of the lower posterior teeth

Question 11

The functional cusps of a tooth contacts with what part of the opposing tooth?

Answer 11

The fossa

Question 12

What cusps contact what fossas in the ICP?

Answer 12

• The lingual cusp of an upper molar contacts the fossa of a lower molar
• The buccal cusp of a lower molar contacts the fossa of an upper molar

Question 13

What action would you ask the patient to perform if trying to use articulating paper to mark tooth contacts in the ICP?

Answer 13

Tap the teeth together

Question 14

What malocclusions might you see in the static occlusion?

Answer 14

• Incisor relationships
  
  • Class I
  • Class II div 1
  • Class II div 2
  • Class III
• Overbite
• Overjet
• Posterior/anterior crossbites
• Anterior/posterio open bites

Question 15

How big is an overbite normally?

Answer 15

2-4mm

Question 16

Describe canine guidance.

Answer 16

• When the mandible moves to the left (working side) there is only contact between the canines
• There are NO posterior contacts (open space)

Question 17

Canine guidance gives what kind of occlusion?

Answer 17

A mutually protected occlusion (the gold standard)

Question 18

Why is mutually protected occlusion (canine guidance) preferable?

Answer 18

• The roots on the canines are adapted for these types of movements
• But the roots on molars aren’t developed for this so don’t want them experiencing lateral movements/forces

Question 19

Where is bilateral group function more commonly seen?

Answer 19

toothwear cases and is more common as patients age

Question 20

Describe the the occlusion/tooth contacts during protrusion.

Answer 20

(The condyle moves forwards and downwards on articular eminence)

• Only incisors +/- canines touch
• No posterior tooth contacts

Question 21

What is an occlusal interference?

Answer 21

undesirable tooth contacts that may produce mandibular deviation during closure to ICP or may hinder smooth passage to and from ICP

Note: . As soon as we deviate from canine guidance, we end up with these

Question 23

What different occlusal interferences do you get?

Answer 23

• Working side
• Non-working side
• Protrusive

Question 24

Describe a working side contact occlusal interference.

Answer 24

Will have the canine and a posterior tooth on the working side contacting

(if moving jaw to left the LHS is the working side)

Similar cusps contact

Question 25

What is a non-working side contact?

Answer 25

Undesireable contact during lateral movement on non-working side Dissimilar cusps contact

Question 26

What is protrusive interference?

Answer 26

This is *any* posterior contact during protrusion.

Question 27

Why do we want to avoid posterior contacts?

Answer 27

* Teeth are designed to absorb heavy forces in the direction of the long axis of the tooth * Won’t like it when lateral forces are applied * Most teeth are not designed to absorb significant lateral forces…………generated by occlusal interferences * Musculature gets a rest as less activity if not undesirable posterior contacts * If teeth were constantly contacting then it will cause muscle problems – tiredness etc. * Occlusal trauma and undesirable tooth movements

Question 28

What pathology regarding occlusion may be present?

Answer 28

- bruxism - tooth wear - occlusal trauma

Question 29

What are the 2 types of bruxism you get?

Answer 29

- essentric - centric

Question 30

What is essentric bruxism?

Answer 30

* The parafunctional grinding of teeth * An oral habit consisting of involuntary rhythmic or spasmodic or functional gnashing, grinding or clenching of teeth in other than chewing movements of the mandible which may lead to occlusal trauma * Side to side movement

Question 31

What is centric bruxism?

Answer 31

* Clenching * The pressing and clamping of the jaws and teeth together * Frequently associated with acute nervous tension or physical effort

Question 32

What are some clinical signs and symptoms of bruxism?

Answer 32

* Toothwear * Fractured restorations * Tooth migration * Tooth mobility (Often in absence of periodontal disease) * Muscle pain and fatigue * Headache * Earache * Pain and stiffness in the TMJ and surrounding muscles

Question 33

What might tooth wear be due to?

Answer 33

* Multifactorial (normally this) * Abrasion * Attrition * Erosion * Abfraction

Question 34

How is tooth wear classed?

Answer 34

mild/moderate/severe

Question 35

What is occlusal trauma?

Answer 35

Occlusal trauma is an injury resulting in tissue changes within the attachment apparatus, including periodontal ligament, supporting alveolar bone and cementum, as a result of occlusal force(s).

Question 36

What are the diff ways that occlusal trauma can be classed?

Answer 36

* Primary * intact periodontium * Secondary * reduced periodontium * Fremitus * palpable or visible movement of a tooth when subjected to occlusal forces

Question 37

What is the checklist you should go through when examining occlusion?

Answer 37

* Incisor relationship * Guidance * Overjet/overbite * ICP contacts * Working/non-working/protrusive contacts (in dynamic occlusion) * Pathology