Exam 1 Dental Anatomy Lectures 1 - 4

What is the function of Incisors?

Cut food, speech, lip support, guide mandible into the intercuspal position

What is the crown shape of the facial view of an incisor

Trapeziod

In the facial view of the crown of an incisor what dimension is greater than the mesiodistal dimension?

the incisogingival dimension

In the facial view of incisors what is the shape of roots?

conical roots taper apically

In the facial view of incisors which angle is more acute than the distoincisal angle?

Mesioincisal angle

In the proximal view, what is the shape of the crown of an incisor?

triangular/wedge and the base in the cervical direction

Which tooth has the greatest concave cervical line curvature

Incisors

Arch Traits of Maxillary Incisors

Wider mesial-distal than facial-lingual, 1st incisor larger than 2nd, heavy lingual anatomy, incisal edge on long axis.

When do Maxillary Central Incisors erupt?

7-8 yrs old

When do maxillary central incisors root complete development?

10 yrs old

When does calcification of maxillary central incisors begin?

3 - 4 months old

When does the enamel of maxillary central incisors complete?

4 - 5yrs old

Which teeth have the longest CROWN

Maxillary Central Incisors

Where do central incisors meet (contact)?

At the midline of the incisal 1/3

Which outline of the maxillary central incisor is more convex?

the distal outline is more convex than the mesial outline

What can you see in the lingual view of a maxillary central incisor?

mesial and distal marginal ridge; cingulum, lingual fossa, cervical line, and the root apex towards the distal

define cingulum

a ridge at the base of the crown

What can you see in the proximal view of a maxillary central incisor?

incisal edge and root apex on the long axis; mesial and distal cervical line curvatures; height of contour from the facial to lingual on the cervical 1/3; facial outline convex

What can you see in the incisal view of a maxillary central incisor?

incisal edge; the mesial to distal dimension greater than the facial to lingual dimension; the mesiomarginal ridge seen longer than the distomarginal ridge

Which teeth have the most variation (variable crown morphology)?

maxillary lateral incisors

At what age do maxillary lateral incisors erupt?

8-9 yrs old

At what age does the root complete in maxillary lateral incisors?

11 yrs old

At what age does calcification of maxillary lateral incisors begin?

10 - 12 months old

At what age does the enamel complete development for maxillary lateral incisors?

4 -5 yrs old

what is the crown ratio for maxillary lateral incisors?

1:1.5

What are some differences between a maxillary lateral incisor and maxillary central incisor?

marginal ridges are heavier; cingulum less obvious; lingual fossa is deeper and often has a lingual groove/pit; root is longer

Where are the contact points on the maxillary lateral incisor

the mesial contact point is at the incisal and middle 1/3 and the distal contact point is at the middle 1/3

Which is the smallest permanent tooth in the mouth?

Mandibular central incisor

At what age does the root development complete on mandibular central incisors?

9 yrs old

At what age does calcification begin in mandibular central incisors?

3 - 4 months old

At what age does the enamel complete on mandibular central incisors?

4 - 5 yrs old

At what age does the mandibular central incisor erupt?

6 - 7 yrs old

describe the facial view of the mandibular central incisor

bilaterally symmetrical; 90 degree incisal angles

what are the contact points of the mandibular central incisor

mesial incisal 1/3 is parallel to the distal incisal 1/3 of the adjacent tooth

decribe the lingual view of the mandibular central incisor

madginal ridges are the same length (confined to the incisal 1/3); lingial fossa not too visible; cingulum is centered

What tooth has very slight anatomy with no grooves, accessory edges or pits?

mandibular central incisors

describe the proximal view of the mandibular central incisor

almost flat facial outline in the middle and incisal thirds; longitudinal grooves on the mesial and distal roots; the incisal edge is more lingual to the long axis

where is the height of contour in a mandibular central incisor?

from the facial to lingual of the cervical 1/3

describe the incisal view of the mandibular central incisor

incisal ridge is lingual to the long axis; bilateral symmetry; proximal sides converge toward the lingual

In mandibular central incisors which dimensions are greater?

facial to lingual dimensions are greater than the mesial to distal dimensions

how does the pulp look like in a cross section of a mandibular central incisor?

pulp cavity is ribbon like shaped; mesial and distal outlines are both concaved

When do mandibular lateral incisors begin to erupt

6 - 7 yrs old

At what age does the root complete development in mandibular lateral incisors

9 yrs old

At what age does calcification begin for mandibular lateral incisors

3 - 4 months

At what age does the enamel complete development for mandibular lateral incisors

4 - 5 yrs old

describe the facial features of a mandibular lateral incisor

M-I angle makes a right angle

D-I angle is more rounded

smooth and longer than the central incisor

Where is the height of curvature for mandibular lateral incisors

at the cervical 1/3

describe the incisal view of a mandibular lateral incisor

similar to the mandibular central incisor but larger; incisal ridge is Not perpendicular to mid axis line but is TWISTED DISTALLY

Concave

Surface that is curved or rounded inward like the interior of a bowl

Convex

Surface that is curved or rounded outward like the exterior of a sphere

Mesial

Towards the midline or center of the dental arch

Distal

Away from the midline or center of the dental arch

Facial

Relating to the front or anterior surface of the tooth

Lingual

Relating to the back or posterior surface of the tooth

Cervical

Relating to the neck of the tooth near the gumline

Incisal

Relating to the cutting or biting edge of anterior teeth

Apical

Relating to the tip or apex of the root of a tooth

Height of Contour (Greatest Convexity)

The greatest curvature (convexity, bulge) on the proximal surfaces

Contact Point

The specific point where the teeth touch in the anterior region

Contact Area

The broader area of contact on the posterior teeth

How many lobes do incisors have?

3

How many lobes do canines have?

4

How many cusps do canines have

1

How many lobes do premolars (bicuspids) have

4

How many cusps do premolars (bicuspids) have

2

How many lobes do molars have

5

How many cusps do molars have?

5

Developmental Lobes

Areas of calcification in the tooth development process

Geometric Shapes of Crown Outlines

Different shapes like triangular, trapezoidal, or rhomboidal that describe the crown of a tooth

Embrasures

V-shaped spaces that help direct food away from the gingival and provide space for the interdental papilla

What is the spillway for food

Embrasures

Interdental Papilla

The triangular-shaped gum tissue between the teeth.

They fill the embrasures

Where are interdental papilla located

Cervical to the contact area

Dental Arch Alignment

The arrangement where mandibular teeth contact two maxillary teeth, including the class counterpart and the tooth mesial to it

When teeth are newly erupted they come closer to having contact points. How are the contact areas formed?

aging and wearing of teeth cause them to broaden

What mandibular tooth has only a mesial contact with a maxillary tooth?

mandibular central incisor

What maxillary tooth has only a mesial contact with a mandibular tooth?

maxillary 3rd molar

What are the functions of canines?

support the lips and facial muscles; shear food; protective mechanism during mastication

Which teeth are protect the lips during mastication?

Canines

Which teeth are located at the self cleansing area of the arch?

Canines

Which TEETH are the longest in the mouth (crown + root)

Canines

Which teeth have the longest SINGLE roots in the mouth?

Canines

define canine eminence

bulge of the canine

What two features do canines not have

mamelons and perikymata

how many lobes do canines have?

4

how many cusps do canines have

one highly development incisal cusp

At what age do maxillary canines erupt?

11 - 12 yrs old

At what age does calcification of maxillary canines begin?

4 - 5 yrs old

When does the enamel development complete in maxillary canines?

6 - 7 yrs old

When does the root development complete in maxillary caninnes?

13 - 15 yrs old

Maxillary Canine - Facial Aspect

developmental depressions on the crown divide the three facial lobes forming a facial ridge.

Maxillary Canine - Lingual View

2 marginal ridges; 2 cusp ridges; 1 lingual ridge; 2 fossae ML and DL; Cingulum

Maxillary Canine - Proximal Views

Broad root facial to lingual; facial outline is more convex; slight linear root depression on the mesial and distal

Maxillary Canine - Incisal View

Facial-lingual measurement greater than mesial-distal, prominent facial ridge with depressions, well-developed cingulum, and visible marginal ridges, lingual fossae, and cusp ridges.

Maxillary Canine Pulp Cavity

Broad facial-lingual pulp outlines, narrow mesial-distal outlines, and an oval pulp outline.

At what age do mandibular canines begin to calcify?

4 - 5 yrs old

At what age does the enamel complete development for mandibular canines?

6 -7 years old

At what age do mandibular canines begin to erupt?

9 - 10 yrs old

At what age does the root development complete?

12 - 14 yrs old

Which tooth has the longest CROWN?

mandibular canine