Occlusion

Question 1

Ideal oclusion definitions

Answer 1

• Mesiobuccal ridge of maxillary 1st molar fits into the mesiobuccal groove of mandibular 1st molar
• Cusp of maxillary canine is in the embrasure between the mandibular canine and mandibular 1st premolar

Question 2

Ideal occlusion ideal relationships

Answer 2

• Ideally, buccal cusps of maxillary teeth are positioned more buccally than the buccal cusps of mandibular teeth
• Ideally, each maxillary tooth is positioned slightly distal (vertical long axis) to the corresponding mandibular tooth of the same type
• Ideally, lingual cusps of maxillary posterior teeth rest in occlusal fossae of the mandibular teeth. Buccal cusps of mandibular teeth rest in occlusal fossae of maxillary teeth

Question 3

Class 1, 2, and 3 malocclusion profile

Answer 3

1= orthognathic (72%)
2= retrograde (22%)
3= prognathic (6%)

Question 4

Labioversion

Answer 4

single tooth, a tooth out of alignment to the labial or buccal compared to other teeth in the arch

Question 5

linguoversion

Answer 5

single tooth, a tooth out of alignment to the lingual compared to other teeth in the arch

Question 6

toriversion

Answer 6

single tooth, a tooth that is twisted around its tooth axis

Question 7

Supraversion, supraeruption or extrusion

Answer 7

single tooth, tooth that is overerupted that is abnormally long relative to the rest of the occlusal surfaced

Question 8

Infraversion or infraocclusion

Answer 8

single tooth, is abnormally short relative to the rest of the occlusal plane

Question 9

Ankylosis

Answer 9

is fusion of cementum to alveolar bone when periodontal ligament is lost, can cause infraversion

Question 10

posterior teeth crossbite

Answer 10

i. Mandibular molars too buccal or maxillary molars too lingual
ii. Maxillary molars too buccal or mandibular molars too lingual

Question 11

anterior teeth crossbite

Answer 11

mandibular incisors are more labial than maxillary incisors

Question 12

overbite

Answer 12

**normal overbite= only the incisal third of mand incisor
overlapped vertically
**deep overbite= maxillary incisors completely overlap mandibular incisor crowns (vertical)

Question 13

Edge-to-edge

Answer 13

incisal edges of both maxillary and mandibular arches occlude

Question 14

open bite

Answer 14

incisor edges of opposing arches do NOT occlude, nor is there vertical overlap when the posterior teeth are closed together

Question 15

over-jet

Answer 15

maxillary incisors are excessively labial/anterior compared to mandibular incisors (horizontal)

Question 16

class 2 division 1

Answer 16

exhibit considerable overjet (often with ALL maxillary incisors tipped labially)

Question 17

class 2 division 2

Answer 17

incisors exhibit deep overbite often with maxillary central incisors tipped lingually BUT lateral tipped labially

Question 18

class 3

Answer 18

• The anterior relationship is often edge to edge OR crossbite
• jaw jutted anterior
• true class 3 if difference in alignment is width of premolar

Question 19

class 2 vs class 3 mandible placement

Answer 19

• *class 2= retrograde profile-Profile has mandibular arch jutted backwards, so mandibular 1st molar and canine are distal of ideal occlusion
• *class 3= prognathic profile- Profile has mandibular arch jutting anterior, so mandibular 1st molar and canine are mesial/anterior of ideal occlusion

Question 20

Crepitation

Answer 20

crackly or grating sound within jaw joint during function when severe overjet present

Question 21

Temporomandibular joint (TMJ)

Answer 21

articulation between the mandible and two temporal bones at the base of the skull; only free moving joint in skull; bilateral articulation; all 3 parts enclosed by fibrous connective tissue

Question 22

Bruxism

Answer 22

grinding teeth at night

Question 23

degultition means?

Answer 23

swallowing

Question 24

functional verses parafunctional tooth contacts

Answer 24

• Functional tooth contacts occur during the normal day to day process of mastication
• Parafunctional tooth contacts occur for clenching or bruxing teeth (or something in your mouth you don’t eat like your own check/tooth or a clarinet reed or pipe or chewing a pencil)

Question 25

Fremitus

Answer 25

palpable or visible movement or vibration of the tooth when subjected to heavy occlusal forces; caused by heavy occlusion

Question 26

Trismus

Answer 26

disturbance of the fibers of the nerve to the chewing muscles; can be a negative side-affect to parafunctional contacts