Lecture 4- Permanent incisors

Question 1

First permanent tooth to errupt

Answer 1

mandibular 1st molar

Question 2

Last PRIMARY tooth to be lost (at age 12, marking the end of the mixed dentition period)

Answer 2

primary 2nd molar

Question 3

What is special about the maxillary central incisors? (5)

Answer 3

1) Esthetically the most prominent teeth
2) Most prone to trauma
3) widest anterior tooth
4) Curvature of the cervical line on mesial aspect of central incisor is greater than that of any other tooth, on any aspect
5) Only maxillary central and mandibular 2nd PM have straight conical roots

Question 4

Maxillary anterior alignment

Answer 4

Inclined mesially form lateral view

Question 5

labial and lingual geometric shape

Answer 5

Trapezoid

Question 6

Proximal geometric shape

Answer 6

Triangle

Question 7

Incisal geometric shape

Answer 7

Triangle/circle

Question 8

Why is is a trapezoid?

Answer 8

Because central incisor is longer cervico incisally than it is wider mesiodistally

Question 9

Distolabial line is more convex on central incisor than the mesiolabial line. This leads to

Answer 9

Point angles:
Mesio-incisal sharp approaching 90 degrees
Disto-incisal angle more convex
(pattern that is repeated in most teeth)

Question 10

Mesial contact area

Answer 10

located at incisal third

Question 11

Incisal embrasure size trend

Answer 11

INCREASE as you move POSTERIORLY

Question 12

lingual embrasure is larger than labial embrasure

Answer 12

1) All teeth have lingual convergence

2) Proximal contact is facial to the center

Question 13

Lingual pit

Answer 13

Sometimes found in lingual fossa

Question 14

Cervical line on central incisor/proximal aspects

Answer 14

Curvature of the cervical line on mesial aspect of central incisor is greater than that of any other tooth, on any aspect

Question 15

Incisal aspect of incisors

Answer 15

Mesiodistal dimension is slightly Greater than labiolingual dimension (bolded)

Cingulum off center to distal side

Question 16

Incisal aspect of incisors

Answer 16

Lingual embrasure is larger than facial embrasure in ALL teeth

Question 17

Incisal root

Answer 17

STRAIGHT CONICAL ROOT (incisors and 2nd maxillary premolar)

Question 18

How many canals do incisors have? (pulp space morphology)

Answer 18

one

Question 19

Occlusion of maxillary central incisor

Answer 19

Occludes with mandibular central AND lateral incisors

Question 20

Maxillary lateral incisor

Answer 20

The last permanent incisor to erupt

Question 21

Peg shaped lateral

Answer 21

lateral incisor that is significantly smaller than it should be

Question 22

congenitally missing lateral incisor

Answer 22

3rd most common congenitally missing tooth

options for treatment: implants or removable prosthesis

Question 23

Maxillary lateral incisor vs maxillary central incisor

Answer 23

lateral- more rounded outlines, more convex (more rounded incisal edge and incisal angles/mesial and distal)

smaller in all dimensions EXCEPT root length

Question 24

Proximal contact area

Answer 24

Mesial: Junction of incisal and middle thirds
Distal: middle third

Question 25

Embrasure area

Answer 25

Distoincisal embrasure is larger than mesioincisal embrasure (bolded)

Question 26

Lingual aspect of lateral incisors

Answer 26

The marginal ridges, cingulum, and incisal ridge are more pronounced (bold) so more accentuated lingual fossa

Question 27

lingual aspect of lateral incisors

Answer 27

lingual pit and lingual developmental groove are more likely

Question 28

Proximal aspect of lateral incisors

Answer 28

Incisal ridge is in line with center of the root

Question 29

Incisal aspect of lateral incisors

Answer 29

Looks like a triangle or OVAL outline (due to prominent cingulum) Incisal ridge is thicker labiolingually compared to the central incisor

Question 30

Pulp space morphology/number of canals of lateral incisors

Answer 30

one

Question 31

root of lateral incisors

Answer 31

single root; distal curvature

Question 32

Occlusion of lateral incisors

Answer 32

mandibular lateral incisor and canine

Question 33

third most common tooth to be congenitally missing

Answer 33

maxillary lateral incisor

Question 34

What is special about the Permanent Mandibular Central Incisor?

Answer 34

It is the smallest tooth | It is the most symmetrical tooth

Question 35

labial surface of mandibular incisors is

Answer 35

bilaterally symmetrical (mesial half is identical to distal half)

Question 36

Proximal contacts and embrasures of mandibular central incisors

Answer 36

Both mesial and distal contact areas are at the same level at the incisal third (bolded) of crown near the mesial and distal incisal angles Both incisal embrasures are the same size and very small

Question 37

lingual aspect of mandibular central incisors

Answer 37

``` The marginal ridges are ill defined lingual fossa small and shallow Shallow smooth cingulum No lingual pit (bolded) ```

Question 38

Incisal aspect

Answer 38

Labiolingual greater than mesiodistal dimension (opposite maxillary teeth). (bolded)

Question 39

Root of mandibular central incisors

Answer 39

Root is convex labially and lingually and flattened mesially and distally (bolded)

Question 40

Pulp space morphology mandibular central incisors

Answer 40

TWO canals with prominent single pulp horn (bold)

Question 41

occlusion

Answer 41

with maxillary central incisor