Occlusal Exam

Question 1

what is the definition of malocclusion

Answer 1

a condition in which there is a deflection from the normal relation of the teeth to other teeth in the same arch and/or to teeth in the oppposing arch

Question 2

what is angle’s classification based on

Answer 2

the relationship of the MB cusp of the maxillary 1st molar and the buccal groove of the mandibular 1st molar

Question 3

what is an angles class 1

Answer 3

MB cusp of the max 1st molar bisects buccal groove of the mandibular 1st molar

Question 4

describe class 1 malocclusion

Answer 4

same as normal occlusion but characterized by crowding, rotations and other positional irregularities

Question 5

what is an angle’s class 2

Answer 5

-MB cusp of max 1st molar is mesial to mand 1st molars buccal groove
-“overbite”

Question 6

what is an angles class 3

Answer 6

-MB cusp of max 1st molar is distal to buccal groove of mand 1st molar
- “underbite”

Question 7

what is overjet

Answer 7

the horizontal overlap of the maxillary central incisors over the mandibular central incisors

Question 8

what is overjet measured with and what is the normal measurement

Answer 8

-periodontal probe
- usually 2-3 mm

Question 9

what is overbite

Answer 9

the vertical overlap of the maxillary central incisors over the mandibular central incisors

Question 10

how is overbite measured and what is the normal number

Answer 10

with a probe vertically,
- 2-3 mm or 20-30% of the mandibular incisors

Question 11

what is erosive tooth wear classified by

Answer 11

the specific mechanism that is responsible for the wear

Question 12

what can cause erosive tooth wear

Answer 12

-erosion
-abfraction
-abrasion
-attrition

Question 13

what is dental wear

Answer 13

part of the normal cycle of the dentition but excessive wear and tooth loss leads to a variety of changes within the oral cavity

Question 14

what is the etiology of dental wear

Answer 14

multifactorial and complex relationships between the 3 types of wear: attrition, erosion and abrasion

Question 15

what is the evidence of occlusal wear/trauma

Answer 15

-wear facets
-broken restorations
-chipped teeth

Question 16

what is the evidence of bruxism

Answer 16

-bony ridges- exostosis or tori
- recesssion
-abfraction
- broken teeth and restorations
-excessive attrition

Question 17

what is abfraction

Answer 17

loss of cervical area due to bruxism
-physical wear along the gingival margin that is not caused by bacterial acid activity

Question 18

what is attrition

Answer 18

mechanical wear of the incisal or occlusal surfaces as a result of functional or para functional movements of the mandible (tooth to tooth contact)

Question 19

what does attrition do to bruxism

Answer 19

accelerates it

Question 20

what can attrition be due to

Answer 20

age

Question 21

in attrition occlusal surfaces match ___

Answer 21

jaw movements and usually have a similar degree of wear

Question 22

what type of erosion is abfraction

Answer 22

physical

Question 23

describe the shape of abfraction

Answer 23

cervical wedge shaped defects

Question 24

what is abrasion

Answer 24

abnormal tooth surface loss resulting from direct frictional forces between the teeth and external objects or from frictional forces between contacting teeth in the presence of an abrasive medium

Question 25

what may abrasion occur from

Answer 25

• improper brushing techniques
  -habits like holding pipe stem by teeth
• vigorous use of toothpicks between adjacent teeth

Question 26

what does improper brushing techniques causing abrasion look like

Answer 26

seen as a sharp V shaped notch in the gingival 1/3 of the tooth

Question 27

where can abrasion occur and what causes each

Answer 27

• interproximal: toothpicks
  -incisal notching: nails, pipe
• cervical: toothbrushing

Question 28

what is erosion

Answer 28

wear or loss of tooth structure by chemicomechanical action

Question 29

what causes facial erosion

Answer 29

lemons, chlorine

Question 30

what causes lingual erosion

Answer 30

bulimia

Question 31

what are oral signs of bulimia

Answer 31

-raised amalgams
-thermal sensitivity
-thinning, chipping of incisal edges
-anterior open bite
-loss of vertical dimension