ANTH 343 - Dentition

Stages of tooth development:

Bud → Cap → Bell Stage

Enamel

Most external part of the tooth - hardest tissue

Dentin

Resilient tissue that forms the middle layer of the tooth

Pulp

Innermost tissue of tooth - has blood vessels and nerves

Cementum

Anchors root of the tooth

Types of teeth:

1. Incisors

2. Canines

3. Premolars

4. Molars

Mesial

Toward the midline of the mouth

Distal

Away from the midline of the mouth

Buccal

Toward the cheeks

Labial

Toward the lips

Lingual

Toward the tongue (down/in)

Palatal

Towards the dental arch (up)

Occlusal

The chewing/biting surface of teeth; premolars and molars

Incisal

Biting, cutting-edge surface of the teeth; incisors and canines

General Trend of The Univeral (US) Numbering System

Starts with top-right Wisdom Tooth, wraps around to bottom-left Wisdom Tooth, ends with bottom-right Wisdom Tooth

General Trend of The Palmer Numbering System

Quadrant based, starting with front-most incisor

Cusp of Carabelli

Cusp mainly in first molars, progressively less likely in 2nd/3rd molars

Shovel-shaped incisors

Incisors have a shovel-like dip; lingual-side

Taurodontism

The pulp region of the tooth is expanded, resulting in shortened & displaced roots

When do baby (Deciduous) teeth come in?

6 months - 2.5 years

When do adult (Permanent) teeth come in?

6-21 years

When do Wisdom Teeth come in?

Whenever they feel like it

What teeth do adults have that children do not?

Premolars

Diastema

Natural gap between teeth

Do humans have a diastema?

No

Prognathism

Protrusion of the upper/lower/both jaws

Evolutionary trends in human dentition:

1. Tooth/jaw size reduction

2. Loss of diastema

3. Reduced prognathism

4. Developing 2.1.2.2. dental formula

Dental Pathology: Caries

Tooth decay

Dental Pathology: Periodontal disease

Bacterial infection that damages gum and bone around teeth

Dental Pathology: Periapical abscesses

Bacteria caused pus pocket at the root of a tooth

Enamel Hypoplasia

Developmental defect wherein teeth have poor, spotty and/or missing enamel

Cultural modifications of teeth include:

1. Fillings

2. Inlays

3. Extractions

Forensic applications of teeth:

1. Age

2. Ancestry

3. Health

4. Diet

5. Forensic ID (bitemarks not reliable in court for conviction)

Human dental formula:

2.1.2.3 (in evolution stage to 2.1.2.2)

Per Quadrant:

2 Incisors

1 Canine

2 Premolars

3 Molars

Layers of the Crown

Enamel → Dentin → Pulp

Layers of the Root

Dentin → Pulp

Why study teeth?

They survive when other skeletal parts degrade; forensic applications

Microscopic Features of Teeth:

1. Striae of Retzius

2. Perikymata

3. Cementum annulations (aging)

Calculus Deposits

Plaque; a calcified deposit commonly found on the sides of tooth crowns

Resorption

A physiological process where living bone cells (osteoclasts) break down and remodel the dental socket (alveolar ridge) following the extraction or loss of a tooth resulting in a smooth, rounded, and filled in new, dense bone.

In what stage do we begin to se the caps being developed?

Bud stage

Molars and premolars have:

Cusps

Incisors and canines have:

Caps

Cementoenamel Junction

Where cementum and enamel meet

What does 1 represent:

Mesial

What does 2 represent:

Distal

What does 3 represent:

Palatal

What does 4 represent:

Occlusal

What does 5 represent:

Labial

What does 6 represent:

Buccal

What does 7 represent:

Lingual

What does 8 represent:

Incisal

Striae of Retzius

A microscopic growth ring inside the enamel matrix caused by severe systemic stress, disease, or nutritional deficiencies during tooth formation

How many subadult teeth do humans have on average?

20

How many adult teeth do humans have on average?

32

What is another name for dental cavities?

Caries

What tooth articulates to the mesial aspect of the right mandibular second premolar?

1st Premolar