Dental Anatomy, Morphology and Occlusion

Front Plane divides body into

Anterior and Posterior portions

Sagittal Plane divides body into

Left and right portions

Transverse (Horizontal) Plane divides body into

Superior and inferior portions

Name 2 out of 8 cranial bones

Left and Right Temporal

Where is the Left and Right Temporal located and shape?

Fan shape

Name 2 important Temporal Bones

Glenoid Fossa
Articular Eminence

How many bones are in the facial portion of the human skull?

14

Name 5 important facial skeletal bones

Left and Right Maxilla
Left and Right Palatine
Mandible

Locate the Maxilla

Form the anterior 2/3 of the hard palate
Nasal cavity

Maxilla supports what

Supports natural teeth in bony sockets by the alveolar process

Locate the Palatine Bone

Parts of the floor and outer wall of the nasal cavity
Hard palate

What does the occlusal view of the Maxilla look like

Locate the Mandible

Few movable bones of the skull
Lower Jawbone

Ramus

Vertical projections of the mandible. Connects masseter muscle for movement of mandible

Alveolar process

Bone that supports natural dentition of the teeth

Supports the teeth and ginival

Mental Foramen

Anterior opening of the mandibular canal. Found between the 1st and 2nd premolar root tips. Mental nerve is passed through this opening

Condyl

-Fits into the glenoid fossa of the temporal bone that makes up the Temporomandibular joint (TMJ)

-Oval shaped structure found on the end of the condyloid process of the mandible

-Located in the lower

TMJ acronym for

Temperomandibular Joint

The right and left TMJ are places where the

where the mandible connects with the rest of the skull at the temporal bone

TMJ is formed by

Glenoid Fossa
Articular Eminence

Condyl

Glenoid fossa

Deep hollow on the undersurface of the zygomatic process of the temporal bone. Condyle stays in the fossa during opening and closing jaw movements

Located in the upper

Articular Eminence

Ramp shaped prominence that extends the forward and downward from the anterior boundary of the glenoid fossa

Located in the upper

Articular disc

Pad of tough, flexible fibrocartilage situated between condyle and glenoid fossa. Shock absorbing mechanism

Synovial cavity

Upper and lower joint compartments. Upper disc found between the top of the disc and glenoid fossa. Lower synovial cavity is found between the bottom of the disc and the condyle of the mandible. Synovial membrane lines the cavity making a lubricating liquid called the synovial fluid

Hinge

Opening or closing motions on the horizontal axis common to both condyles

Protrusion and Retrusion Translatory aka

Sliding movements - translatory

Protrusion

Forward movement of mandible

Retrusion

Backwards movement of mandible

Left and Right lateral movements of the mandible

Working side is the area you chew on one side
Non working side is the opposite end of the chewing

How many classifications of levers are there

3

What Class Lever is the normal mandibular jaw

Class 3 - like a fishing pole
Fulcrum is the TMK and the load is where the food goes

How many muscles of Mastication are there? Name them

4
Masseter Muscle

Temporalis Muscle

Medial Pterygoid

Lateral Pterygoid

Masseter action

Elevates the mandible, aid in the protruding of the mandible

Temporalis action and shape

Fan shape
Closes the jaws / can dislodge without it

Retrude or pull back the mandible

Medial Pterygoid action

Closes the lower jaw
Move the mandible sides or lateral excursion

Lateral Pterygoid action

Both lateral pterygoid muscles contract together. Mandible is pulled forward into protrusion.
One muscle contracts independently from one another, the mandible shifts into lateral excursion

Buccinator location and action

Pulls corners of the mouth laterally and hold food between teeth while chewing

Orbicular Oris location and action

Closes the lips

Mylohyoid muscle

Forms the floor of the mouth (lower)
Can dislodge a mandibular denture

Geniohyoid Muscle

Sits directly on top of the mylohyoid muscle

How many systems to identify teeth? Names?

3
Universal
FDI

Palmer

What is the Universal Tooth Numbering System?

Maxillary has 1-16
Mandibular has 17-32

FDI acronym for

Federation Dentaire Internationale

Whats the numbering system for FDI

Top Right from midline = 11-18
Top Left from midline = 21-28
Bottom Right from midline = 31-38
Bottom Left from midline = 41-48

Whats the numbering system for Palmer

4 quadrants, from midline 1-8

Child’s teeth term and how many

20 Deciduous Teeth

First deciduous teeth to erupt is

Mandibular cental incisor

First permanent dentition to erupt

First molars - 6 year molar

Exfoliation

Shedding of primary teeth to be replaced by permanent teeth

Purpose of incisors and canine

Incisor - cut food
Canine - tear food

Purpose of premolar / bicuspid / molars

Grind food

How many embrasures types are there

4
Facial
Lingual
Gingival / Cervical / Apical / Interproximal Space
Occlusal / Incisal

Emergence Profile

Contour of a tooth as it relates to the adjacent tissue

Overditching a die will

cause an unnatural emergence profile

How many contact surfaces are there? Name them

3
Mesial and Distal aka Proximal
Occlusal / Incisal

Maxillary 1st molar shape

Rhomboidal

Mandibular 1st molar shape

Trapezoidal

How many lobes do teeth have?

Lobes are developmental grooves = 4 to 5

Which tooth has the most lobes

Mandibular first molar with 5 lobes

How many surfaces does a line angle have

2

How many surfaces does a point angle have

3

Whats a long axis and which way does it lean

Imaginary line passing lengthwise through the center of a tooth - distal lean

Incisals are sharper on which end

Mesioincisal point

Only tooth with oblique ridge

Maxilary molars

Triangular ridge

Enamel from cusp to central sulcus

Transverse Ridge

Union of buccal and lingual triangular ridge

Lingual fossa is seen on

Anterior teeth

Triangular fossa is seen on

Posterior teeth

Centra fossa is seen on

Molars and mandibular second premolars

Mamelons

Small, rounded projections of enamel from the incisal edge of newly erupted anterior teeth

When do mamelons wear away

After age

Which tooth has the largest cingulum of all anterior teeth? And the longest tooth?

Maxillary Canine - Cuspid

Which way does the oblique ridge run on the maxillary first molar?

Mesiolingual cusp to distobuccal cusp

Cusp of Carabelli

Mesiolingual cusp of the 1st maxillary molar - nonfunctioning and secondary cusp

What teeth only occludes on 1 surface?

Mandibular central incisor and last Maxillary molar

How many variations of occlusal groove patterns? Name them

3: H, Y, and U pattern

Mandibular second premolar possesses 3 cusps, which is the largest

Mesiolingual cusp

Anatomic crown vs Clinical Crown

Enamel

White, compact, and very hard substance that covers and protects dentin of crown of teeth

What is enamel made up of and strength

96% inorganic materials and 384 MPA strength

Dentin

Tissue of the tooth under the enamel that makes up bulk of the tooth

Apex

Root tip

Apex Foramen

Opening of root tip that nerves and blood vessels enter and leave tooth

Shearing cusps

Guiding, Non loading baring cusps that do not normally occlude with opposing occlusal surface - BULL (Buccal Upper, Lingual Lower)

Stamping cusps

Supporting Cusp that occludes with the occlusal surface of the opposing teeth - LUBL (Lingual Upper, Buccal Lower)

Cusp to embrasure

Natural dentition

Cusp to fossa

Used for fixed prosthetic dentistry to avoid fracture and food traps

Attached gingiva

Gingiva that is tightly bound to bone

Free gingiva

About 0.5mm wide and is found at the neck of the tooth

Interdental Papilla

Potion of the free gingiva that fills the proximal space between contact areas of adjacent teeth. Prevents food traps

Curves of Occlusion

Curve of Spee

Curve of Wilson

Monson’s Sphere

Curve of Spee

Anterior posterior seen from the side

Curve of Wilson

Lateral curve seen from the anterior

Monson’s Sphere

Ideal occlusion touches an imaginary sphere - 8 inches in diameter

Compensating Curve

Combination of Curve of Spee and Wilson

Centric Relation

RUM - Rearmost, Uppermost, Midmost Condyler position
No contact between teeth
Space is known as Freeway Space

Centric Occlusion

MIP - Maximum Intercuspation

Maximum Intercuspation

Complete intercuspation of the opposing teeth independent of the condyler position