Perio

Question 1

What is the basic definition of occlusion in general dictionaries?

Answer 1

The act of closure or being closed.

Question 2

What does the dental definition of occlusion include?

Answer 2

It includes the static, morphological tooth contact relationship and factors related to masticatory system stability and function.

Question 3

What is the primary role of occlusion in oral motor behavior?

Answer 3

It involves the use of teeth in functional and parafunctional activities.

Question 4

Define occlusal trauma.

Answer 4

Injury resulting in tissue changes within the attachment apparatus due to occlusal force.

Question 5

Define occlusal traumatism.

Answer 5

Functional loading of teeth off-axis, sufficient to induce temporary or permanent changes in teeth or supporting structures.

Question 6

What is acute trauma from occlusion?

Answer 6

Abrupt occlusal impact with high magnitude and short duration, often caused by biting on hard objects.

Question 7

What is chronic trauma from occlusion?

Answer 7

Gradual changes due to tooth wear, drifting, or parafunctional habits like bruxism, with low magnitude and long duration.

Question 8

What is primary occlusal trauma?

Answer 8

Tissue changes due to excessive occlusal forces on teeth with normal support.

Question 9

What is secondary occlusal trauma?

Answer 9

Tissue changes due to normal or excessive occlusal forces on teeth with reduced support.

Question 10

What type of force is mainly produced during mastication?

Answer 10

Compression forces produced by the masseter muscle.

Question 11

What type of force acts on anterior teeth during mastication?

Answer 11

Shear forces with a horizontal component.

Question 12

What type of force acts on posterior teeth during mastication?

Answer 12

Compressive forces with a vertical component.

Question 13

Why are horizontal forces more detrimental in occlusal traumatism?

Answer 13

They lead to tipping, rocking, and misplacing of teeth.

Question 14

What are th anatomical actions during centric relation (CR)?

Answer 14

TMJ is at rest, and muscles hold the jaw in the least strained position.

Question 15

What anatomical changes occur during centric occlusion (CO)?

Answer 15

Teeth take over the load when maximum intercuspation occurs, supported by muscles.

Question 16

What is fremitus?

Answer 16

A palpable or visible movement of a tooth when subjected to occlusal forces.

Question 17

How is tooth mobility graded?

Answer 17

Grade 0: Physiological; Grade 1: <1 mm total; Grade 2: >1 mm total; Grade 3: Vertical displacement.

Question 18

What is a widened PDL space a sign of?

Answer 18

It indicates occlusal trauma or increased mobility.

Question 19

What clinical sign occurs in occlusal trauma involving the gingiva?

Answer 19

Gingival recession caused by direct contact or functional overload.

Question 20

What radiographic feature may indicate root resorption?

Answer 20

A visible resorption of root structure on X-rays.

Question 21

What are the three stages of tissue response to occlusal trauma?

Answer 21

Injury, repair, and adaptive remodeling.

Question 22

What occurs during the injury phase of occlusal trauma?

Answer 22

Bone resorption under pressure and PDL fiber tearing under tension.

Question 23

What happens during the repair phase?

Answer 23

Damaged tissues are replaced with new bone, cementum, and connective tissue.

Question 24

What is the purpose of adaptive remodeling?

Answer 24

To create a structural relationship where forces are no longer injurious.

Question 25

What is the direction of forces during functional activity?

Answer 25

Vertical forces increase while horizontal forces decrease.

Question 26

What is the magnitude of force during functional activity?

Answer 26

20-30 lbs.

Question 27

What is the duration of functional activity daily?

Answer 27

About 20 minutes per day during eating and swallowing.

Question 28

What is the direction of forces during parafunctional activity?

Answer 28

Horizontal forces increase, causing tipping and rocking of teeth.

Question 29

What is the force magnitude during parafunctional activity?

Answer 29

250-300 lbs.

Question 30

What is the duration of parafunctional activity?

Answer 30

About 40 minutes per hour due to habits like clenching and bruxism.

Question 31

Why are natural teeth more adaptive to forces compared to implants?

Answer 31

Natural teeth have a periodontal ligament, which absorbs and distributes forces.

Question 32

What type of forces are implants most vulnerable to?

Answer 32

Excessive occlusal forces, especially horizontal and cantilever forces.

Question 33

How do implants respond to excessive occlusal forces?

Answer 33

They may cause crestal bone resorption and loss of osseointegration.

Question 34

What is the significance of bone density in implant occlusion?

Answer 34

Lower density bones (like D4) are more susceptible to overloading and bone loss.

Question 35

Why should maximum intercuspation be avoided in implants?

Answer 35

Implants lack proprioceptors in the PDL, leading to uncontrolled force distribution.

Question 36

What is a common overloading factor for implants?

Answer 36

Overextended cantilevers or large occlusal tables.

Question 37

What is the treatment focus for primary occlusal trauma?

Answer 37

Occlusal adjustment to prevent further tissue damage.

Question 38

What is the first step in treating secondary occlusal trauma?

Answer 38

Addressing inflammation with scaling, root planing, and oral hygiene measures.

Question 39

How does occlusal adjustment help in periodontitis cases?

Answer 39

It reduces mobility and enhances periodontal healing.

Question 40

When is splinting necessary in cases of occlusal trauma?

Answer 40

For mobile teeth with a healthy but reduced periodontium to increase comfort and prevent fractures.

Question 41

What are signs that occlusal adjustment may improve periodontal treatment outcomes?

Answer 41

Premature contacts, fremitus, or cervical abfraction.

Question 42

What is the modulus of elasticity of natural tooth structures?

Answer 42

Ranges from 9 psi for bone to 14 psi for dentin and cementum.

Question 43

Why is ferrule height critical in post-and-core restorations?

Answer 43

It dissipates occlusal forces, reducing stress concentration and failure.

Question 44

How much ferrule height is needed for anterior teeth?

Answer 44

2 mm on both labial and lingual surfaces.

Question 45

How do horizontal forces affect anterior teeth with posts?

Answer 45

Stress concentration occurs at the cement line or post-to-tooth junction, risking failure.

Question 46

What happens if excessive occlusal forces act on dental implants?

Answer 46

They can lead to crestal bone resorption due to force concentration at the bone-implant junction.

Question 47

How should implant designs differ from natural teeth?

Answer 47

Avoid rules of natural teeth; ensure force distribution aligns with implant limitations.

Question 48

Why is bone remodeling more significant in implants under excessive force?

Answer 48

The mismatch in modulus of elasticity between implants and bone concentrates forces at weak points.