Oral biology final Flashcards
The color that results when the mucosa is constantly irritated and the epithelium becomes thicker
White
The type of dentin that continually form throughout ones life time
Secondary dentin
Each tooth develops from ___ or more growth centers known as developmental lobes that grow out from the tooth germ
4
These are incisal ridges on anterior teeth separated by developmental grooves
Mamelons
Anterior teeth have ___ facial lobes and ___ lingual lobes
3,1
Which molar usually has a 5th lobe/cuspid
1st molar
Which premolar may have 2 or 3 cusps
Mandibular 2nd
Mandibular teeth usually erupt ___ maxillary teeth
Before
All deciduous teeth are usually erupted by what age
2.5 years old
As the child grows the jaw also grows but the erupted teeth do not grow any larger, creating space and separations between the teeth called
Primate spacing
The first permanent teeth to erupt are usually the
First molars
Which teeth act as the foundation for the rest of the permanent denition
1st molars
It is not uncommon for permanent incisors to erupt ___ to deciduous Incisors while deciduous incisors are still in place
Lingually
Which teeth break the rule of mandibular teeth erupting before maxillary teeth
Maxillary 2nd premolars
Teeth that do not completely erupt, but remain embedded in bone, or soft tissue
Impacted teeth
As teeth erupt and meet the teeth in the opposing arch they form what is called
Occlusal plane
The period of denition that begins about 6 years of age and lasts while both primary and secondary teeth are present
Mixed dention
Which of the following is not a function of the teeth
Unscrewing bottle cap
The crown of the tooth is covered with
Enamel
The whole crown of the tooth that is covered by enamel, whether it is erupted or not
Anatomic crown
Any unerupted part of the tooth
Clinical root
The hardest tissue in the body
Enamel
The type of dentin that is laid down in response to caries or tramua
Tertiary/ Reparative dentin
Nutrition for cementum is derived from outside of the tooth through ___ coming directly from bone
Blood vessels
Incisors are designed to ___ food
Cut
Molars are designed to ____ food
Grind
A depression or concavity on a tooth
Fossa
An elevated portion of a tooth that runs in a line
Ridge
Spaces between the teeth that are occlusal to the contact areas
Embrasures
The widest part of the crown of the tooth is called the
Height of contour
How many succedaneous teeth are there?
20
Of the 3 possible anterioposterior relationships in primary occlusion which is the most common?
Mesial step
As the primary molars are exfoliated they are replaced by permanent premolars causing extra space called
Leeway space
Horizontal alignment of the teeth is due to the equilibrium of 2 factors the tongue, and
Lips and cheeks
When one or more teeth in the mandibular arch are located facial to the opposing maxillary teeth
Cross bite
When the anterior teeth do not touch, but are widely separated when their centric occlusion
Open bite
According to angles classification system the mesiobuccal cusp of the maxillary 1st molar occludes with the buccal groove of the mandibular 1st molar is
Class 1
In lateral mandibular glide side which no teeth are contacting is
No working side
In the general rules of tooth identification, if tooth roots curve they usually curve
Distally
Which teeth are the most commonly congenitally missing teeth after the third molars
Maxillary lateral incisors
What is the age of eruption of the permanent maxillary central incisors
7-8 years old
The smallest teeth in the entire dentition
Mandibular central incisors
The nerves in the pulp of the tooth elicit what type of response
Pain
if a tooth is lost a tooth in the opposing arch may erupt too far into the mouth
Supraeruption
The roots of molars tend to be ___ the more posteriorly they are positioned
Shorter
Which teeth are the longest in the entire dentition
Maxillary canines
Canines are designed to __ food
Hold and tear
AN area of the root that is not covered by cementum can cause
Sensitivity
Which of the premolars usually have 2 roots
Maxillary 1st premolar
Any ridge that runs from the cusp tip to the central groove of the occlusal surface of the tooth is
Triangular ridge
What makes the mandibular 1st premolar unique
A functional lingual cusp
The 3 cusp type of the mandibular 2nd premolar may have a groove pattern on the occlusal surface resembling what letter
Y
Which cusp form of the mandibular 2nd premolar is more common
3 cusp
54.2% have 3cusp, 43% have 2 cusp, 2.8% have 4 cusps
The crown measurements of posterior teeth are ___ cervicoocclusally than anterior teeth
Shorter
How many nonsuccedaneous teeth are there?
12
What is the name of the 5th supplemental cusp of the maxillary 1st molar
Cusp of carabelli
What is the occlusal outline of. The maxillary 1st molar
Rhomboidal
What is the eruption time of the maxillary 2nd molars?
11-13 years
What is the occlusal outline of the maxillary 2nd molar
Heart shapped
How many roots do the maxillary molars have
3 roots
Of the 3 maxillary molars roots which is the longest?
Lingual/ palatal root
How many cusps does the mandibular first molar have
5
What pattern is formed on the occlusal surface of the mandibular 1st molar
Y
What is the geometric shape of the occlusal surface of the mandibular 2nd molars?
Rectangular
How many cusps do Mandibular 2nd molars have
4
Mandibular molar usually have how manny pulp canals
3 mesiobuccal, mesiolingual, and distal
How many teeth are in the deciduous dentition
20
Which deciduous teeth are usually the first to erupt
Mandibular central incisors
Which deciduous teeth are wider mesiodistally than the permanent teeth that replace them
Deciduous molars
How is the color of the deciduous teeth different from the permanent teeth
Lighter
How are the pulp cavities of deciduous teeth different than permanent teeth
Large in proportion to crown size
An anomaly that occurs before birth or at birth is
Congenital
Where do supernumerary teeth most commonly occur
Maxillary midline and molars
Which teeth are least likely to be congenitally missing
Canines
Teeth which are situated buccally or lingually to a molar
Paramolars
A condition when 2 adjacent tooth germs unite they maybe united long part or the entire length of the tooth union must occur at the dentin
Fusion
Condition which occurs when there is a failure of the hertwigs epithelial root sheath to properly invaginate horizontally, creating elongated pulp chambers with short stunted roots
Taurodontism
Indentation at the midline of the upper lip
Philtrum, its derived from embryonic medial nasal processes
A change is identical embryonic cells to become distinct structurally and functionally
Differentiation
There are two types of cells involved in the initiation of tooth development. One type is oral epithelial cells. What is the other?
Mesenchymal cells
During which week is the dental lamina seen?
6th week
The 1st stage of enamel organ development, the bud stage starts in the ___ embryonic week
8th week is the initial budding of the 10 thickened areas of the dental lamina
During the cap stage the mesenchyme forms the dental papilla which becomes
Pulp
This is the outermost part of the structure of the cap stage and is directly continuation of the basal cell layer
OEE
Appearance of the stratum intermedium is the beginning of what stage of enamel organ development
Bell stage
This is an extension to the lingual side of each developing primary tooth
Successional lamina
Which embryonic layer does dentin come from
Mesoderm
Which embryonic layer does enamel come from
Ectoderm
What are the cells that form enamel
Ameloblasts
What are the cells that form the dentin
Odontoblasts
What is the inorganic composition of enamel
96%
The primary unit of enamels structure
Enamel Rod
How many ameloblasts together form one enamel rod?
3-4
What is the shape of the enamel rod?
Keyhole
the stage of enamel development when the hydroxyapatite crystals are deposited into the enamel matrix
Mineralization stage
What is the inorganic composition of dentin
70 %
The bulk of the Dentinal material is the “glue” that holds all the tubules together
Intertubular dentin
The type of dentin that is formed when the tooth erupts and comes into contact with the opposing tooth
Secondary dentin
Reparative dentin is formed in response to local Rama and is located immediately beneath the trauma area. The type of trauma that is usually the result of cavity preparation is called
Mechanical trauma
Which of the following are the peripheral cells of the pulp
Odontoblasts
Which cells are the protection for the pulp
Macrophages
During the bell stage the point where the OEE meets the IEE is located at the deepest part of the enamel organ
Cervical loop
The tip of the epithelial root sheath that turns horizontally inward
Epithelial diaphragm
The 3 components of the attachment apparatus are cementum,periodontal ligament and
Alveolar bone
These are cells of the epithelial root sheath that have pulled away from the dentin and are found in the PDL space next to the tooth
Epithelial rest cell
What is the inorganic component of cementum
45-50%
As cementum is laid down it may assume 3 different relationships with the enamel of the crown what is the most common?
Cementum overlaps enamel
The type o cementum where the cementoblasts remain on the surface instead of becoming entrapped in cementum. They are located in the cervical 2/3 of the root
Acellular
Ends of the periodontal ligament fibers that become surrounded by cementoblasts are called
Sharpeys fibers
Alveolar bone originates from which embryonic layer
Mesoderm
Layer of bone is radiographically referred to as the lamina dura
Cribriform plate also called alveolar bone proper
The PDL fibers which run from cementum to alveolar bone
Alverolodental fibers
Alveolodental fiber group of PDL fibers that is only on multi rooted teeth
Interradicular group
When a tooth is lost the tooth posterior to it will usually tilt forward into the unoccupied space this is know as
Mesial drift
Phenomenon that refers to the total life span of the tooth from the crown development until the tooth is lost or the person dies
Active tooth eruption
Type of eruptive movement in high the crown of the tooth developers while the bottom of the socket fills in with bone, pushing the crown towards the surface
Spatial
Tooth movement in the eruptive stage tends to be
Occlusal and facial
The stage of eruption that takes place when the teeth come into occlusion
Post eruptive stage
Type of mucosa found on the gingiva and hard palate
Masticatory mucosa
The oral mucosa membrane is composed of stratified squamous epithelium and
Connective tissue
The type of stifled squamous epithelium which has a surface layer with layers of dead cells without nuclei
Keratinized
Type of stratified squamous epithelium that has cells on the surface with nuclei that are healthy and normal
Nonkeratinized
Lining mucosa
Nonkeratinized to parakeratinized
Tissue on the gingiva and hard palate is
Parakeratinized to keratinized
The peak of gingiva that extends coronally between the teeth is the
Interdental papilla
Part of the interdental papilla that is apical to the contact area is
Col
The shallow groove around the tooth
Gingival sulcus
The connective tissue beneath the mucosa that contains blood vessels, nerves and connective tissue
Submucosa
Of the 4 stages of passive eruption the stage that is considered pathological and is frequently referred to as gingival recession
Stage 4
The attaching of epithelium to tooth is an extremely active process, and the cells providing for this attachment are replace every
3-5 days
What direction do the rods run
DEJ to the surface of the crown
