1st lecture comparative dentistry

Question 1

What has a functional basis?

Answer 1

Every curve and segment of a normal tooth

Question 2

Four Phylogenetic Classes of Tooth Forms

Answer 2

1. Single Cone (haplodont)
2. Three Cusps in line (Tricondont)
3. Three Cusps in a Triangle (Tritubecular Molar)
4. Four Cusps in a quadrangle (quadritubecular molar)

Question 3

Single Cone

Answer 3

haplodont

Question 4

Three Cusps in line

Answer 4

trricondont

Question 5

Four Cusps in a quadrangle

Answer 5

quadritubecular molar

Question 6

Haplodont

Answer 6

Reptilian Stage

-Simplest form of tooth= single cone

Question 7

Characteristics of Haplodonts

Answer 7

-Many teeth in both jaws
-Jaw movement is limited, to simple open and close- hinge
-NO OCCLUSIOn of teeth
-Teeth used for prehension or combat

-Main function is procurement of food. Jaw movements are related and government by tooth form in all cases

Question 8

Tricondont

Answer 8

Easy Mammalian Stage

-Three Cusps in a line in posterior teeth

-The Largest cusp is centered- with a smaller cusp located anteriorly and posteriorly

-Carnivores have teeth representing this form

Question 9

Tritubercular

Answer 9

Dogs and Carnivores

-THREE Cusps in a Triangle

-Three cornered tritubercular molar arrangement

-teeth bypass each other more or less when jaw is opened or closed

Question 10

Tritubercular

Answer 10

Dogs and Carnivores

-THREE Cusps in a Triangle

-Three cornered tritubercular molar arrangement

-teeth bypass each other more or less when jaw is opened or closed

Question 11

Quadritubercular

Answer 11

-First time that one reflects occlusal contact relationship between the teeth of upper and lower jaws.

Four Cusps in a quadrangle!

Question 12

Apes

Answer 12

Have similar dentition to humans.

Main difference is the development of the canines, arch form, and jaw development!

Question 13

Lobes

Answer 13

The multiplication and fusion of lobes during tooth development are demonstrated graphically when human teeth are viewed from the mesial or distal aspects. Anterior teeth, which are used for incising or apprehending food, reflect the single cone, whereas the posterior or multicusped teeth, which are used for grinding food in addition to having a shearing action, appear to be two or more cones fused

Question 14

What represents a primary center of formation?

Answer 14

Each Lobe of a tooth- this ALL teeth appears to be a combo of four or more lobes!

Question 15

Primary Center of Formation

Answer 15

Mamelon, Cingulum, Cusp Tip

Question 16

Anterior Teeth

Answer 16

Mesial, Labial/Facial, Distal, and Lingual Lobe

Question 17

Premolars

Answer 17

Mesial, Buccal, Distal, Lingual- if you are a 3 cusp variety of the Mandibular 2nd Molar, you have a mesiolingual and distolingual lobe!

Question 18

Molars

Answer 18

Named as the cusps

1: Mesiobuccal Cusp = Mesiobuccal Lobe

Question 19

Isognathus

Answer 19

Jaws of equal size
Trait is to LIMIT lateral movement

Question 20

Anisognathous

Answer 20

Jaws of unequal size
Trait tends to increase mobility of the mandible in a lateral direction

Question 21

Bunodont

Answer 21

Refers to tooth-bearing conical cusps

Question 22

Selenodont

Answer 22

Characterized by low crowns, crescent shaped cusps when viewed from above

Question 23

Tooth form and jaw movements of humans

Answer 23

Humans are bunodont and relatively isognathus- not perfectly isognathus because the maxillary arch overlaps horizontally the mandibular arch

Question 24

Geometries

Answer 24

All aspects of each tooth crown except the incisal or occlusal aspect may be outlined schematically by these three shapes:

1) Triangle
2) Trapezoid
3) Rhomboid

Question 25

Anterior Teeth from the Proximal Shape

Answer 25

Triangular Because these teeth are prehensile

Question 26

Trapezoid

Answer 26

All TEETH from the facial/lingual- with the longest uneven side toward the occlusal/incisal and the shorter side at the cervix This allows for two antagonist in opposing arch

Question 27

Shape of the Proximal surface of Maxillary Posterior Teeth

Answer 27

Trapezoids- with the shortest uneven side toward the occlusal, longer side at the cervix Helps to penetrate food, without constriction, the occlusal forces could be overwhelmed for the base of crown.

Question 28

Shape of Proximal Surface of Mandibular Posterior Teeth

Answer 28

Rhomboids The rhomboidal form inclines the crown in a lingual direction. Long axes of maxillary and mandibular teeth are kept parallel to one another

Question 29

Each tooth of the dentition has two antagonist-- what is the exception

Answer 29

Except the mandibular central incisor

Question 30

Form and Function

Answer 30

Incision, prehension, and trituration

Question 31

Human Dentition

Answer 31

Omnivores

Question 32

A general restorative principle states that occlusal forces in dental restorations should be directed along which axis of teeth?

Answer 32

The long axis

Question 33

Interproximal Form

Answer 33

*Proximal contacts protect the soft tissue between teeth Tissue that occupies this space is called the interdental papilla or gingival papilla

Question 34

Dehiscence

Answer 34

Partial absence of bone over the tooth

Question 35

Fenestraton

Answer 35

Window or hole in the bone with an intact gingival alveolar process

Question 36

Root Form

Answer 36

Associated with the overall form of the tooth and the work it has to do. The angle of the incisal and occlusal surfaces of anterior and posterior teeth are positioned to be placed OVER the center of the root or WITHIN confines of the root trunk

Question 37

Roots of which teeth are flared for stabilization

Answer 37

Posterior teeth

Question 38

Is the dental arch flat?

Answer 38

No

Question 39

Curvature of Spee

Answer 39

Anterior to Posterior curvature of dentition

Question 40

Curvature of Wilson

Answer 40

FACIAL TO LINGUAL CURVATURE OF THE POSTERIOR TEETH

Question 41

Compensating Occlusal Curvature

Answer 41

Is a combination of the curve of spee and the curve of Wilson

Question 42

Overjet

Answer 42

Horizontal overlap

Question 43

Overbite

Answer 43

vertical overlap