Dental Anatomy Facts Part 3 Flashcards
When the mandible moves from CO to edge to edge, what do the condyles do
Condyles move forward and downward
when the mandible moves from CO to edge to edge, what does the non-working condyle do
moves downward, forward, and medial
What plays the greatest role in discluding the posterior teeth in latero-protrusive movements
Anterior guidance
Teeth are in contact in intercuspal position during non masticatory swallowing or during masticatory swallowing
Non masticatory swallowing
What almost exclusively determines intercuspal position
Tooth contact
What is a tooth guided position and what is a ligament guided position
Tooth guided - Centric occlusion or intercuspal position
Ligament guided - Centric relation
In Posselt’s envelope, what is the most superior point
Maximum intercuspal position = intercuspal position = CO
Bennet Movement
Side shift of the mandible toward the working condyle, the side it’s moving to
When does Bennet movement occur
During the earliest stage of lateral movement
What is postural position
Physiological rest position
About 2mm lower than CO
Is Postral position a border position
no
Mandibular postral position determined almost exclusively by what
mandibular musculature
If you move from postral position to CO, use what muscle
Use anterior fibers of temporalis
Curve of Spee
the Anterior-posterior curvature of the occlusal surfaces as seen in a facial/buccal view
- think weeee, sliding down the teeth
Curve of Wilson
Curved bridge from left to right side inside the mouth
Overjet
Horizontal overlap
- Usual overjet is 2-4 mm
- think jet on the horizon
Overbite
Vertical overbite
-think, you bite up and down
The main component of enamel
inorganic matter
not collagen
Direction of enamel rods in permanent teeth in cervical third
Gingival direction or not towards the incisal/occlusal
rods in cervical third of deciduous teeth run incisal-cervically
Perikymata
Result from the normal enamel apposition - seen on outside surface
-Manifestation of striae of Retzius on enamel surface
Striae of Retzius
Developmental disturbances inside tooth in the enamel
-run obliquely from DEJ to enamel surface
For multi-rooted teeth, where does dentin most rapidly form
at the floor and roof of pulp chamber
Caries stimulates production of what
tertiary dentin
Percentage of dentin that is organic
20-30%
Primary function of dental pulp is
to form dentin
-not to nourish or provide sensation
What is the dentin and pulp formed from
Dental Papilla
-think D.P. - dental papilla and dentin pulp
Dentin that is most highly mineralized is
Intra or peritubular dentin
- Peritubular - right around the odontoblastic process
- INTERtubular dentin is in between two processes
The DEJ occurs at what two structures during development
dental papilla and inner enamel epithelium
-DP cells in contact with IEE = odontoblasts
Softest dental tissue
cementum
2 types of cementum, where are they
Acellular - coronal 2/3
-Cellular - apical 1/3, think that the cells are down where the blood supply is coming from
When viewed from the occlusal, the arrangement of the teeth are what shape,
however, the 4 or 5 posterior teeth are aligned in what shape
all teeth in parabolic shape
posterior teeth aligned in straight line
All teeth develop from how many lobes
What are the exceptions
All teeth develop from 4 lobes
- Except permanent first molars - 5 lobes
- And mandibular 2nd premolar 3 cusp type - 5 lobes
Marginal ridges of mand first premolar
mesial marginal ridge more cervical than the distal
All teeth have distal and mesial marginal ridges - true or false
true
What separates cusp ridges from marginal ridges
developmental grooves
Union of a facial and lingual triangular ridge
Transverse ridge
How many teeth in permanent dentition normally have a cingulum, which are they
All 12 anterior teeth
What percent of the total F-L dimension is made up by the occlusal table of posterior teeth
55-65%
What makes up the periodontium
Gingiva, PDL, Cementum, Alveolar bone (junctional epithelium is often included)
-epithelial attachment - junctional epithelium
How wide is PDL normally and with age
PDL is 0.2 mm wide
-Old age decreases to 0.1 due to deposition of cementum and bone
Attachments of PDL fibers
tooth (cementum) to dental alveolar bone
Attachments of gingival fibers
tooth (cementum) to gingiva
What is the predominant connective tissue for PDL fibers
Type 1 collagen
What fibers provide the major support for a tooth during function
Oblique fibers
Which fiber reduces the likelihood of forceful impaction into alveolus
Oblique fibers
Group of fibers most likely found in middle third of root
Oblique fibers
Most prevalent type of PDL fiber
Oblique fibers
Transseptal fibers are PDL or gingival fibers
Gingival fibers
Attachments of transseptal fibers
Tooth to tooth
About how much of permanent root is formed when tooth erupts
50%
When is the apex of a tooth fully formed after it erupts
about 2-3 years
Function of the pulp
form dentin - primary function
- supply nutrients to dentin
- transmit sensory stimuli
Which teeth have facial heights of contour in cervical third
All except mandibular molars
Lingual heights of contour found where
Anterior teeth - cervical third
-Posterior teeth - middle third except MD 2nd premolar is in occlusal third
Location of lingual height of contour on mand 2nd premolar
occlusal third
Where is the greatest depth of curvature of the cervical line of permanent teeth
Mesial aspect
Where does the CEJ dip deeper
Ant teeth than post
Max than mand
Mesial than distal
Greatest on mesial of max central incisor
Think max central incisor as model for all of these
Supernumerary teeth commonly where
between maxillary centrals
or as a 4th molar sometimes
Concrescence
when cementum of two teeth join together
Oligodontia
presence of fewer than normal teeth - 6?
Which aspect of mand central opposes the which part of max central
distoincisal aspect of mand central opposes lingual fossa of max central
Exceptions to picket fence drawing
Lingual cusps of max premolars contact the distal fossa of respective mand premolars because of mesial slant of lingual cusp
(max 2nd premolar lingual cusp contacts distal fossa of mand 2nd premolar)
In a cusp to fossa contacting relationship in ICP, max first premolar is most likely to articulate with mand first premolar - this is due to lingual inclination of max first premolar. Mand second premolar is not involved in cusp to fossa manner
