3. Dental anatomy:
The study of the development, morphology,
function, and identity of each tooth in the
human dentition.
As well as:
The way in wich the teeth relate to other teeth in
the same dental arch and to teeth in the opposite
arch.
6. Formation of the dentition
Humans have two sets of teeth in their lifetime.
First set : primary or deciduous dentition, begins
at 14th weeks in utero and is completed at about 3 years
postnatally .the first teeth begin to appear in mouth at
6th month and the last one at 28th _+4month.
Second set : permanent dentition completed at 14-15
year for second permanent molar(but transition or
mixed dentition from 6th -12th year because the
human has decideouos and permanent teeth).
7. Why mixed period of dentition is a difficult
time for young child ?
Missing teeth
Teeth of different colors
Crowding , malposed teeth .
exfoliation
shedding
=
16. Formula for human teeth
Deciduous : I22 C11 M22 = 10
I 22 means incisors 2 upper , 2 lower
C22 means canines 1 upper ,1 lower
M22 means molars 2 upper , 2 lower
The total =10 in two quadrant
10 * 2 =20 tooth(milk or baby tooth)in
full mouth
17.
18. Permanent :I 22 C 11 P 22 M 33
Total = 16 in two quadrant
16*2=32 in full mouth
46. Cusp
Is an elevation or mound on crown portion of a tooth;
making up a divisional part of the occlusal surface.
47. Tubercle
Is a smaller elevation on some portion of the crown
produced by an extra formation of enamel
48. Cingulum
Latin word for”girdle”
It is the lingual lobe of an anterior tooth . It makes the
cervical third of the lingual surface .
49. Ridge
Any linear elevation on the surface of of the tooth and
is named according to its location
Examples:
- incisal ridge
- marginal ridge
- buccal ridge
50. Marginal ridges
Are rounded borders of enamel that form the mesial
and distal margins of the occlusal surfaces of molars
and premolars
and the mesial and distal margins of the incisors and
canine
51. Triangular ridges
Desend from the tip of the cusp of molar and premolar
toward the central part of the occlusal surface .
How do they name? according to the cusp they belong
to.
Example:buccal cusp ridge.
53. Fossa
An irregular depression or concavity
Ligual fossae: are on lingual surface of incisors
54. Triangular fossa
Located adjacent to the marginal ridges on the
occlusal surfaces of posterior teeth. Two types of
triangular fossae are mesial and distal
55. Central fossae
Are on the occlusal surfaces of molars ,they formed by
the convergence of ridges terminating at a central
point in the bottom of the depression where there is a
junction of grooves
56. sulcus
is a long depression or valley in the surface of a tooth
between ridges and cusps, the inclines of which meet
at an angle. A sulcus has a developmental groove at the
junction of its inclines
57. developmental groove
a shallow groove or line between the primary parts of
the crown or root
Buccal and lingual grooves
58. supplemental groove
A less destinct, shallow linear depression on the
surface of a tooth, but it is supplemental to
adevelopmental groove, and does not mark the
junction of primary parts
MLCR, mesiolingual cusp ridge; LDG, lingual
developmental groove; DLCR, distolingual cusp ridge;
DTF, distal triangular fossa (outlined area); DCR, distal
cusp ridge; DBDG, distobuccal developmental groove;
DBCR, distobuccal cusp ridge; MTF, mesial triangular
fossa (outlined area); SG, a supplemental groove.
59. Pits
Small pinoint depressions located at the junctions of
developmental groove or terminals of those grooves.
60. Lobe One of the primary sections of formation in the
development of the crown .
Cusps and mamelons are representative of lobes .
Mamelon:one of three tubercles on the cutting edge
of a newly erupted incisor tooth.
71. Summary of schematic outlines
Triangles:
six anterior teeth , maxillary and mandibular
A-mesial aspect
B-distal aspect
72. Summary of schematic outlines
trapezoids:
I. Trapezoids with longest uneven side toward occlusal
or incisal surface:
A. All anterior teeth , maxillary and mandibular
1-labial aspect
2-lingual aspect
B. All posterior teeth
1- buccal aspect
2- lingual aspect
73. Summary of schematic outlines
trapezoids:
II. Trapezoids with shortest uneven side toward occlusal
or incisal surface:
A. All maxillary posterior teeth
1-mesial aspect
2- distal aspect
74. Summary of schematic outlines
rhomboids:
All mandibular posterior teeth
1-mesial aspect
2- distal aspect
75. Interproximal form
Proximal contacts of approximating teeth in the arch
protect the soft tissue(gingiva) between the teeth and
referred to as interproximal space
Interdental papilla
76. Interproximal form
Normally the gingiva covers part of cervical third of
the crown and fills the interproximal spaces.
The gingival line follows the curvature but not
necessarily the level of the cervical line .
77. Interproximal form
The cervical line is a stable anatomical demarcation.
The level of gingival line is variable.
Absence of bone over the root of the tooth is called
dehisence(clift) or fenestration(window).
78. Interproximal form
Cervicoenamel ridge
It is also called cervical ridge.
It is curvature on the crown at the cervical third above the
cervical lin.
This ridge shouldn’t be overcontoured or undercontoured
in full-crown restorations.
79. Root form
Root form(shape and length) is associated with:
- overall form
- work
Of the tooth
80. Root form
Mesial view of the anterior tooth will show that the incisal
ridge or cusp is centered over the root
The measurment from cusp tip to cusp tip buccolingually is
much less than the buccolingual diameter of the root base
81. Contact area
A part of mesial or distal surface wich contacts the
neighbouring tooth.
point
line
area
82. diastema
is a space that exists between two adjacent teeth in the
same arch that is not the result of a missing tooth.
It is most commonly seen between the maxillary right
and left central incisors, but can occur between any
teeth
83. Embrasures(spillways)
when two teeth in the same arch in contact ,their
curvature adjacent to the contact area form spillway
space called embrasures.
84. Significance of Embrasure form
Serves as a spillway for food material during
mastication
Prevents food from being forced through the contact
area and injuring the periodontal tissues.
Also, Enhances the self-cleansing process of the tooth
by exposing the surfaces to oral fluids, mechanical
cleansing, and friction from the tongue, lips, and
cheeks
