Midterm Review – Dentition, Bone Biology & Cranial Anatomy

A comprehensive set of vocabulary flashcards covering dentition, tooth development, bone biology, joint types, evolutionary theory, and key cranial bones and landmarks for midterm preparation.

Incisors

Sharp cutting teeth at the front of the jaw

Canine

Pointed tooth used for tearing food

Incisors

Sharp cutting teeth at the front of the jaw

Canine

Pointed tooth used for tearing food

Premolars

Bicuspid transitional teeth located behind canines

Molars

Large, flat teeth specialized for grinding

Neural crest-derived mesenchyme

Embryonic connective tissue from neural crest that contributes to tooth and craniofacial structures

Oral epithelium

Ectodermal lining of the mouth that forms the enamel organ

Condensing dental mesenchyme

Aggregated mesenchyme beneath the enamel organ during early tooth development

Ameloblasts

Enamel-secreting cells derived from oral ectoderm

Odontoblasts

Cranial-neural-crest cells that produce dentin

Enamel

Hard, non-regenerative outer covering of the tooth crown

Dentin

Regenerative calcified tissue beneath enamel and cementum

Dental pulp

Soft connective tissue in the tooth’s center containing nerves and blood vessels

Thickening stage

Initial epithelial proliferation in tooth development (E11.5 in mouse)

Bud stage

Enamel organ invaginates mesenchyme (E13.5)

Cap stage

Enamel organ forms cap over dental papilla (E14.5)

Bell stage

Histodifferentiation stage shaping the future crown (E18.5)

Erupted tooth

Postnatal stage when tooth emerges into the oral cavity (≈P35)

Crown

Visible part of a tooth above the gum line

Root

Portion of a tooth anchored in alveolar bone

Enamel-dentine junction

Boundary where enamel meets dentin

Dentogingival junction

Interface between tooth surface and gingiva

Cementum

Bone-like tissue covering the tooth root

Periodontal ligament

Fibrous connective tissue attaching tooth to alveolar bone

Alveolar bone

Jaw bone that houses tooth sockets

Striae of Retzius

Weekly incremental growth lines in enamel

Cross striations

Daily incremental growth lines in enamel

Digastric muscle

Suprahyoid muscle that depresses mandible and opens mouth

Lateral pterygoid (inferior head)

Muscle that depresses and protrudes the mandible

Masseter

Powerful elevator and protractor of the mandible

Temporalis

Fan-shaped muscle that elevates and retracts the mandible

Medial pterygoid (superior head)

Muscle that elevates and mediates lateral movements of mandible

Osteoblast

Bone-forming cell that secretes osteoid

Osteoclast

Multinucleated cell responsible for bone resorption

Osteocyte

Mature bone cell maintaining bone matrix

Osteoid

Unmineralized bone matrix produced by osteoblasts

Cortical bone

Dense outer layer of bone providing strength

Spongy bone

Trabecular bone filling the interior of many bones

Woven bone

Immature, disorganized bone formed during growth or repair

Lamellar bone

Mature, organized secondary bone resistant to fracture

Primary bone

First bone laid down, often atop woven scaffold

Secondary bone

Lamellar bone formed during remodeling

Intramembranous ossification

Direct bone formation within a connective tissue membrane (e.g., skull)

Endochondral ossification

Bone formation that replaces a cartilage model (e.g., long bones)

Fontanelle

Membrane-covered gap between fetal skull bones aiding birth & brain growth

Origin (muscle)

Attachment site that remains relatively fixed during contraction

Insertion (muscle)

Attachment site that moves during contraction

Synovial joint

Freely movable joint with capsule, cavity, and synovial fluid

Fibrous joint

Joint united by dense fibrous tissue, allowing little/no movement

Cartilaginous joint

Bones joined by cartilage permitting limited movement

Synchondrosis

Primary cartilaginous joint composed of hyaline cartilage

Symphysis

Secondary cartilaginous joint composed of fibrocartilage

Cranial suture

Fibrous joint between skull bones

Syndesmosis

Fibrous joint united by ligament or membrane (e.g., tibia-fibula)

Gomphosis

Peg-in-socket joint between tooth roots and jaw bone

Ontogeny

Developmental changes occurring throughout an organism’s life

Sexual dimorphism

Skeletal differences between males and females

Individual variation

Idiosyncratic morphological differences among individuals

Linnaean classification

Hierarchical taxonomy using binomial nomenclature (Genus species)

Morphological species concept (MSC)

Defines species based on physical traits

Biological species concept (BSC)

Defines species as interbreeding groups reproductively isolated from others

Homo genus

Human lineage (≈2.3 mya-present) characterized by bipedalism & larger brains

Basicranial flexion

Bending of cranial base associated with speech & expanded brain

Parabolic dental arcade

Bow-shaped tooth row typical of Homo

Frontal bone

Bone forming the forehead and superior orbits

Parietal bone

Paired bones forming sides and roof of cranial vault

Temporal bone

Bone housing ear structures and forming part of the zygomatic arch

Occipital bone

Posterior skull bone containing the foramen magnum

Sphenoid bone

Butterfly-shaped cranial base bone with the sella turcica

Ethmoid bone

Porous midline bone forming nasal septum & cribriform plate

Maxilla

Upper jaw bone that holds upper teeth

Nasal bone

Small paired bones forming the bridge of the nose

Lacrimal bone

Small bone of medial orbital wall with lacrimal groove

Mandible

Lower jaw bone housing the lower teeth

Zygomatic bone

Cheek bone forming part of zygomatic arch

Supraorbital foramen

Opening in frontal bone above the orbit for nerve and vessels

Supraorbital notch

Incomplete variant of the supraorbital foramen

Metopic suture

Midline frontal suture present in infants; may persist in adults

Meningeal grooves

Grooves on inner parietal bone for middle meningeal vessels

Zygomatic process

Projection of temporal bone contributing to cheek arch

Mastoid process

Conical projection of temporal bone for muscle attachment

External auditory meatus

Bony ear canal opening in temporal bone

External occipital protuberance

Midline projection on occipital bone for ligament attachment

Foramen magnum

Large opening in occipital bone for spinal cord passage

Sella turcica

Pituitary-housing depression on sphenoid bone

Lesser wing of sphenoid

Small wing forming part of orbit roof

Greater wing of sphenoid

Large wing forming cranial floor and lateral skull wall

Pterygoid process

Inferior projection of sphenoid for muscle attachment

Crista galli

Vertical ethmoid projection for falx cerebri attachment

Anterior nasal spine

Midline projection of maxilla beneath nose

Incisive foramen

Opening in maxilla posterior to incisors for vessels/nerves

Mental eminence

Chin prominence on anterior mandible

Condylar process

Posterior mandibular process forming the temporomandibular joint

Coronoid process

Anterior mandibular process for temporalis insertion

Alveolar process

Tooth-bearing ridge of maxilla or mandible