Lecture 4 Mandibular Incisors Flashcards
what are the numbers of the mandibular central incisors
24 and 25
what number is the right lateral mandibular incisor
23
what number is the left mandibular lateral incisor
26
what are embrasures
the spaces that widen out from the contact
what is the interproximal contact
where two adjacent teeth contact each other
what are the embrasure spaces of anterior teeth
incisal, gingival, facial, lingual
what are the embrasure spaces of the posterior teeth
occlusal, gingival, facial, lingual
what are the relationships between embrasures in the anterior teeth
-incisal < gingival
- facial = lingual
what are the relationships between embrasures in the posterior teeth
- occlusal = gingival
- facial < lingual
what makes up the gingival embrasure
the interdental papilla
what are mandibular incisors used for
incise or cut food
what tooth is the smallest tooth in the mouth
the mandibular central incisors
which incisors in the mandible are smaller
the central incisors
which tooth has the smallest mesiodistal diameters
mandibular central incisors
describe the relationship between buccolingual measurement and mesiodistal measurement of the mandibular incisors
broader buccolingually than mesiodistally
describe the shape of the mandibular central incisor from the facial view
trapezoidal, tapers cervically
describe the incisal outline of the mandibular central incisor
straight, mamelons are present when the tooth erupts
describe the mesioincisal and distoincisal angles of the mandibular central incisor
both are 90 degrees
what tooth is the only symmetrical tooth in the mouth
mandibular central incisor
where are the mesial and distal contact areas for the mandibular central incisor
both contacts are at the same level in the incisal 1/3
describe the labial surface of the mandibular central incisor
-smooth, no developmental depressions
- flat in incisal 1/3 and becomes for convex cervically
describe the root of the mandibular central incisor
single root, narrow mesiodistally, curves distally in some cases
- root length is greater than crown length
describe the shape of the central incisor from the lingual view
-trapezoidal in outline
-smooth and rounded, slightly concave but no lingual fossa
describe the ridges and the cingulum of the mandibular central incisor from the lingual view
-mesial and distal marginal ridges are only minor elevations
- cingulum is much less distinct than in the maxillary incisors
- no developmental grooves
describe the shape of the mandibular central incisor from the mesial view and the height of contour
-triangular in outline
-labial outline is convex
- height of contour is in the cervical 1/3rd
from the mesial view of the mandibular central incisor where does the incisal edge lie in respect to the line bisecting the root
lingual
describe the CEJ of the mandibular central incisor from the mesial view
CEJ curves incisally about 1mm more than on the distal
what happens to the mandibular central incisor when worn
the incisal edge angles to the facial
describe the cervical line of the mandibular central incisor from the mesial aspect (Lingual vs labial)
cervical line extends 1mm more apically on the lingual than on the labial
describe the root of the mandibular central incisor
extends straight from CEJ and tapers apically from middle 1/3
- may have broad developmental depression along its length (depression is greater on distal root than mesial)
describe the differences of the mandibular central incisor from the distal view compared to the mesial view
-cervical lines curves incisally 1 mm less distally than on mesial
- developmental depression on distal of root is greater than on mesial
describe the incisal edge in comparison to a line bisection the crown labiolingually of the mandibular central incisor
incisal edge is at right angles to the line
- incisal edge lies lingual to center of the tooth
where are the contact areas of the mandibular central incisor from the incisal view
they are centered labiolingually
describe the width of the labial surface vs the lingual surface from the incisal view of the mandibular central incisor
the MD width of the labial surface is wider than the MD width of the lingual surface
describe the root and pulp of the mandibular central incisor
single root, root is broader FL than MD
- developmental depressions on mesial and distal (D > M)
-usually one pulp canal but 40% of population has 2 pulp canals (facial and lingual canals if 2)
how is the mandibular lateral incisor bigger than the central incisor
wider MD than the central incisor, all extra width appears to be added to the distal aspect of the tooth
describe the crown height of the mandibular lateral incisor from the facial view
distal crown height is often shorter than the mesial crown height, incisal edge slopes downward distally
describe the distoincisal angle and the mesioincisal angle of the mandibular lateral incisor from the facial view
mesioincisal is 90
distoincisal is rounded
where are the mesial and distal contacts of the mandibular lateral incisor from the facial view
incisal 1/3. distal contact is more cervical than the mesial
describe the lingual view of the mandibular lateral incisor compared to the mandibular central incisor
same
describe the difference between the distal view and mesial view of the mandibular lateral incisor
the distal aspect is twitsed lingually. the lingual surface is not visible from distal
describe the incisal edge of the mandibular lateral incisor
lingual to the center of the tooth
describe the distofacial line angle of the mandibular lateral incisor from the incisal view
DF is more lingual
describe the pulp canal on the manibular lateral incisor
typically one canal, but can have 2 40% of the time
