lec 2 - normal occlusion

Question 1

as the static, closed contacting position of upper teeth to lower teeth - shawn

Answer 1

Dental Occlusion

Question 2

as a separation of teeth from occlusion; the opposite of occlusion

Answer 2

Harvet Stallard - Disocclusion of Teeth

Question 3

referred to as normal
occlusion orthodontically

Answer 3

Angle’s Class I occlusion

Question 4

key teeth for Angle’s Class I

Answer 4

permanent 1st molars

Question 5

Angle’s Class I occlusion

Answer 5

mesiobuccal cusp of maxillary 1st molar should occlude in mesiobuccal groove of mandibular 1st molar

Question 6

Normal occlusion usually
involves: (6)

Answer 6

ü occlusal contact
ü alignment of teeth
ü overjet
ü overbite
ü arrangement + relationship of teeth between arches
ü relationship of teeth to osseous structures

Question 7

Normal implies a situation
commonly found in ___________

Answer 7

absence of disease

Question 8

it should include not only a range of anatomically acceptable values but also ___________________

Answer 8

physiologic adaptability

Question 9

concept refers both to an
aesthetic + physiologic ideal

Answer 9

Ideal Occlusion

Question 10

important aspect of ideal
occlusion includes: (3)

Answer 10

ü functional harmony
ü stability of masticatory system
ü neuromuscular harmony in the masticatory system

Question 11

Ø an occlusion which is judged to be causative factor in formation of traumatic lesions

Ø disturbances in
supporting structures
of teeth, muscles + TMJ

Answer 11

Traumatic Occlusion

Question 12

studied 120 casts of non-orthodontic patients with normal occlusion for 4 years (1960-1964)

Answer 12

Lawrence F. Andrews

Question 13

According to Andrews, ______ to normal occlusion contributed individually + collectively to total scheme of occlusion

Answer 13

6 keys

Question 14

essential for orthodontic treatment to be considered successful

Answer 14

Andrew’s Six Keys to
Normal Occlusion

Question 15

Andrew’s Six Keys to
Normal Occlusion

Answer 15

Ø Key I: Molar Relationship
Ø Key II: Crown Angulation
Ø Key III: Crown Inclination
Ø Key IV: Absence of Rotations
Ø Key V: Tight Contacts
Ø Key VI: Flat Curve of Spee

Question 16

molar relationship should be such that the:

Answer 16

§ distal surface of distal marginal ridge of upper 1st permanent molar
§ contacts + occludes with mesial marginal ridge of lower 2nd molar

Question 17

mesiobuccal cusp of upper 1st permanent molar falls:

Answer 17

within the groove between
mesial + middle cusps of lower 1st permanent molar

Question 18

mesiolingual cusp of upper 1st molar seats in:

Answer 18

central fossa of lower 1st molar

Question 19

In normally occluded teeth, gingival portion of long axis

§ line bisecting clinical crown mesiodistally

Answer 19

Crown Angulation (Mesiodistal Tip):

Question 20

Crown Angulation:

ü of each crown is ________ to occlusal portion of that axis
ü ___________ varies with each tooth type

Answer 20

distal
degree of tip

Question 21

___________ causes a tooth to occupy more space.

Answer 21

Too much angulation

Question 22

angle between a line 90
degrees to occlusal plane

Answer 22

Crown Inclination (Labiolingual / Buccolingual Torque)

Question 23

line tangent to the middle of labial or buccal surface of clinical crown

Answer 23

Crown Inclination (Labiolingual / Buccolingual Torque)

Question 24

crown of maxillary incisors are so placed that incisal portion of labial surface is labial to gingival portion of clinical crown

Answer 24

Crown Inclination (Labiolingual or Buccolingual Torque)

Question 25

In normally occluded teeth, gingival portion of long axis

§ or line passing through most permanent part of labial or buccal surface of a tooth

Answer 25

Crown Angulation (Mesiodistal Tip):

Question 26

In all other crowns, occlusal portion of labial or buccal surface is lingual to gingival portion

Answer 26

Crown Inclination
(Labiolingual or Buccolingual Torque)

Question 27

In __________, lingual crown inclination is slightly more pronounced

ü compared to cuspids + bicuspids

Answer 27

maxillary molars

Question 28

In _________________, lingual inclination progressively increases

Answer 28

mandibular posterior teeth

Question 29

Anterior teeth:

Deciduous – more ______________.

Permanent teeth – more _____________.

Answer 29

vertically oriented
labially inclines

Question 30

Properly inclined teeth → ____________________

Improperly inclined teeth → ________________

Too much inclination → ________

Answer 30

proper intercuspation
poor intercuspation
protrusion

Question 31

teeth should be free of undesirable rotations

ü if rotated, a molar or bicuspid occupies ____________ than it would normally

ü a rotated incisor can occupy ____________ than normal

Answer 31

more space
less space

Question 32

Non-rotated tooth occupies __________ than a rotated tooth.

Answer 32

less space

Question 33

In absence of such abnormalities as genuine tooth-size discrepancies.

Answer 33

TIGHT CONTACTS

Question 34

Contact points should be ________.

Answer 34

tight.

Question 35

_______________ is a
must for stability of occlusion

Answer 35

flat occlusal plane

Question 36

Flat Curve of Spee is measured from __________________

Answer 36

the most prominent cusp of lower 2nd molar to the central incisor

Question 37

Flat Curve of Spee

ü ____________________ is acceptable from a standpoint of stability

Answer 37

no curve deeper than 1.5 mm