Studevant's Chapter 1 Clinical Significance of Dental Anatomy, Histology, Physiology, and Occlusion Flashcards
The human dentition is called?
Omnivorous
Because the diet consists of animal and plant foods
Incisors are used to?
Shear (cut through) foods
Canines function to?
seizing, piercing, tearing and cutting of food
provide lip support and speech (phonetics) and esthetics
Premolars function to?
tear and grind food
(having qualities of both canines and molars)
provide lip support and crucial in esthetics
Molars function to?
crush, grind, and chew food for swallowing
maintain vertical dimension of the face
What are the 3 structures of teeth?
Enamel, Pulp-Dentin, Cementum
Amelogenesis
Enamel formation caused by ameloblasts
Fissure
non coalesced developmental lobes that create a deep invagination in the deep groove area of enamel
Pit
non coalesced enamel at the deepest point of a fossa
What are the constituents of enamel?
Inorganic material or mineralized (calcium hydroxyapatite) 96%
Organic matrix proteins 1%
Water 3%
Incremental striae of Retzius
Growth rings that form during amelogenesis
Imbrication lines of Pickerill
alternating grooves that are formed when the growth rings at the enamel are incomplete
Perikymata
Elevations between the grooves/lines of Pickerill
Hunter Schreger Bands
Where the direction of the enamel rods change
Nasmyth membrane
A membrane that covers a newly erupted tooth and is worn away by mastication and cleaning
Pellicle
replaces the nasmyth membrane by way of salivary proteins
Enamel Maturation
where the permeability of enamel decreases with age because of the changes in the enamel matrix
What are the 4 functions of the pulp?
formative (developmental)
nutritive
sensory (protective)
defensive/reparative
Pulp has 2 parts
The coronal portion (in the crown portion of the tooth)
The radicular portion (in the root portion of the tooth)
What is dentinogenesis?
Dentin formation
What cell bodies create dentin?
Odontoblasts
What are the odontoblastic processes that cross into the DEJ in the enamel called?
Enamel Spindles
Where is predentin located?
Next to the cell bodies of odontoblasts
What is primary dentin?
The dentin that forms the initial shape fo the tooth
What are the constituents of Dentin?
70% Inorganic
20% Organic
10% Water
What is the hydrodynamic theory?
Stimulus initiated rapid tubular fluid movement within the dentinal tubules that account for nerve depolarization
Reversible pulpitis?
mild to moderate injury causing a reversible inflammatory response when pathology is removed
Irreversible pulpitis?
Severe injury that causes irreversible inflammatory response
What forms cementum?
Cementoblasts
What are the constituents of Cementum?
45-50% inorganic material
50-55% organic material: collagen and protein polysaccharides
What is the difference between acellular and cellular cementum?
Acellular: Coronal half of root
Cellular: Apical half of the root
What is the CEJ?
Cementoenamel Junction, where the cementum meets enamel
What are the 4 main functions of teeth?
Mastication
Esthetics
Speech
Protection of supporting tissues
What does the proximal height of contour provide?
contacts with proximal surfaces of adjacent teeth
adequate embrasure space apical to contact for gingival tissue
What is the tissue called between each gingival embrasure?
Gingival or interdental papilla
What are the 4 functions of the periodontal ligament?
Attachment and support
Sensory
Nutritive
Homeostatic
Principle fibers of the ligament serve to?
Connect cementum to the alveolar bone to suspend and support the tooth
What does occlusion mean?
Closing; The contact of the teeth in opposing dental arches when the jaws are closed.
What is tooth contact called during mandibular movement?
Dynamic occlusal relationship
The central groove separates what cusps?
The facial from the lingual cusps
What are the depressions between cusps called?
fossae (fossa)
What are functional cusps?
The cusps that contact opposing teeth along the central fossa occlusal line
Each cusp has four ridges, what are they?
Outer Incline (facial or lingual ridge)
Inner Incline (triangular ridge)
Mesial cusp ridge
Distal cusp ridge
What are non functional cusps?
The cusps that overlap opposing teeth
What is MI?
Maximum Intercuspation, where the position of the mandible is when it is in full contact with a persons full dentition
What depression does the mandible articulate with the temporal bone at?
The glenoid fossa
Function of the enamel?
To protect the dentin and the pulp?
The enamel is the ____ substance in the body?
Hardest
What is the elastic modulus?
a quantity that measures an object or substances resistance to being deformed elastically when a stress is applied to it (High: Stiff, Low: Flexible)
What is compressive strength?
the resistance of a material to breaking under pressure
What is tensile strength?
is the maximum strength a material can withstand while being stretched or pulled before breaking or deforming
Enamel is both strong and brittle. Enamel has ___ elastic modulus, ___ compressive strength and ___ tensile strength?
high
high
low
Dentin is strong and resilient. Dentin and ___ elastic modulus, ___ compressive strength, and ___ tensile strength?
low
high
high
What are the four functions of pulp?
Formative,
Nutritive,
Sensory (Protective),
Reparative
What is the coronal pulp?
The pulp that is located in the crown of the tooth
What is the pulp called in the roots of the teeth?
Radicular pulp
What is the opening from the pulp into the PDL near the apex of each tooth called?
Apical foramen
What are Sharpey Fibers?
Collagen fibers from the PDL that are partially inserted into the outer surface of the cementum at 90 degrees or perpendicular
