ANATOMY OF DENTAL PULP

2.  Introduction
 Development of pulp
 Disturbances in formation of pulp
 Methods of detecting of detecting anatomy
 Anatomy of pulp
 Pulps of maxillary teeth
 Pulps of mandibular teeth
 Differences in primary and permanent
 Age changes
 Clinical considerations
 Conclusion

3.  Pulp is a connective tissue which is present in
central portion of the tooth
 As it is central portion it is also known as “Heart of
the tooth”
 This connective tissue is highly vascularised and
unique and dose not resemble any of the tissues
in the human body

4.  Due to all these features it is also referred to as an
“Organ”
 So let us know more in depth about this organ

5.  The tooth pulp is initially called as the dental
papilla
 Tissue is designated only as “pulp” only after
dentin forms around it
 In the earliest stage of tooth development it is an
area of proliferation future papilla that causes oral
epithelium to invaginate and form enamel organ

6.  The enamel organ enlarge to enclose the dental
papilla in their central portion which is the future
pulp
 The cell density of dental papilla is greater
because of proliferation of cells within it
 Young dental papilla is highly vascularised
 Cells of dental pulp appear as undifferentiated
mesenchymal cells

7.  These cells develop into stellate shaped
fibroblasts
 When inner enamel epithelium differentiate into
ameloblasts, the odontoblasts then differentiate
from peripheral cells of dental papilla, when dentin
production begins the tissue is no longer called as
dental papilla, now designated by dental pulp
organ

8.  Dense invaginatus (Dense in Dente):
 It results from an infolding of enamel organ during
proliferation and is an error in
morphodifferentation
 Causes may be increased localized external
pressure, focal growth retardation, focal
stimulation in certain areas of tooth bud
 Often results in an early pulp-oral communication
which requires early root canal treatment

9.  They show varying degree of severity and
complexity
 Maxillary laterals are frequently involved and
lingual pit is the mildest form

10.  Dense evaginatus:
 It appears as an accessory cusp or “globule of
enamel” on the occlusal surface of teeth
 These are common in mandibular premolars
between buccal & lingual cusps
 They often contain an extension of pulp
 If fragile tubercles fracture or wear off, the pulp
may get exposed and there may be a necessity
pulp treatment accordingly

11.  Lingual groove:
 It appears as a surface infolding of dentin oriented
from cervical towards apical direction, usually
present on maxillary laterals
 It results in a deep narrow periodontal defect that
occasionally communicates with pulp causing an
endo-perio problem
 Treatment is difficult, and usually requires
extraction

12.  Dilacerations:
 It is a severe or a complex curvature or a bend in the
root or the crown portion
 During development, structures such as cortical bone
of maxillary sinus or mandibular canal or nasal fossa
may deflect epithelial diaphragm
 Another cause might be trauma during development of
root
 Modification of type of instrument may be necessary
for preparation of these canals
 Roots having severe curvature or bend cannot be
negotiated

13.  Taurodontism:
 It represents an increase in proportion of crown to
the roots
 Crown is more in length than the roots
 Pulp chambers of molars might be below the
middle thirds of the tooth also
 Pulp horns might be also at an higher level than
expected, a radiographic evaluation might be
necessary during restorative procedure also

14.  Textbook knowledge:
 Gaining knowledge from textbook is most important
and most useful method
 Radiographic evidence:
 Radiographs can be termed as great pretenders as
they often are misleading and helpful
 They are certainly useful, particularly conventional
periapical films
 Radiographs tend to make canals look uniform in
shape and tapered. In fact aberrations are often found
and generally not visible

15.  Exploration:
 Additional determination of pulp anatomy can be made
during access preparation and when searching canals
 Newer technology:
 Newer techniques such as digital radiography, digital
subtraction radiography, tomography
 Micro CT – it is very accurate and has ability to
determine morphology not visible on conventional
radiographs. Creates a 3 dimensional image

16.  The dental pulp occupies the center of each tooth
and consists of sift connective tissue
 Every person normally has 52 pulp organs – 32
permanent & 20 deciduous
 Each pulp organ resides in pulp chamber which is
surrounded by dentin
 Total volumes of all pulp organs is 0.38cc, mean
volume is 0.02cc
 Molar pulps are 3-4 times more larger than incisor
pulps

17. Coronal pulp- central
portion of crown
 Each pulp organ
Radicular pulp- root
portion

18.  Coronal pulp in young individuals resembles the
outer portion of the crown dentine
 It has 6 surfaces – the roof or occlusal, mesial,
distal, buccal, lingual and floor
 Pulp horns are protrusions that extend into cusp of
each crown
 No. of pulp horns depends on no. of cusps
 Cervical region of pulp is constricted

19.  In a young tooth pulp horns are at an higher level
than the older teeth
 It may be necessary to take a radiograph for the
extent of caries weather it is closer to pulp which
may lead to an unintentional exposure
 Factors such as physiologic ageing, pathosis and
occlusion all modify the dimensions of pulp
chamber by production of secondary and tertiary
dentin

20.  Because of continuous deposition the pulp
becomes smaller with age
 This is not uniform throughtout the coronal pulp
but progresses faster on the floor than on roof or
side of walls

21.  The radicular or the root pulp is the pulp entering
from the cervical region of crown to root apex
 In anterior teeth they are single and in posterior
are multiple
 They are not always straight and vary in size,
shape and number
 Variations may be as follows

24.  Usually two closely lying canals in a single root may
have communication
 This kind of communication is known as isthmus
 Isthmus is a narrow ribbon shaped communication
between two root canals that contain pulp or pulpally
derived tissue
 Isthmi must be found, prepared and filled, because
they can function as bacterial reservoirs
 A root with two or more canals may have an isthmus

26.  Communication between
pulp and PDL is not limited
to apical foramen
 Accessory are one arising
from the radicular pulp
laterally through root
dentin at any level through
the root end has a
communication with
periodontal space

27.  The mechanism of formation is not known clearly
 They are likely to occur in areas where there is
premature loss of root sheath cells as these cells
from odontoblasts which form dentin
 They may also occur where developing root
encounters a blood vessal, the vessel may be
locked in an area where dentin is forming and the
hard tissue may develop around it

28.  They are most commonly and numerously found
in the regions of apical root
 In molars or premolars they also occur near
bifurcation or trifurcation areas of root
 They are clinically significant in spread of infection
, either from pulp to PDL or vice versa

29.  Concept of apical root
anatomy is based upon three
anatomic and histologic
landmarks in the apical region
of root
 Apical constriction (AC)
 Cement dentinal junction
(CDJ)
 Apical foramen (AF)

30.  The root apex has root canal tapering from the
canal orifice to the AC
 The AC generally is considered the part of root
canal with smallest diameter
 The CDJ is point in the canal where cementum
meets dentin
 This is point where pulp tissue ends and
periodontal tissue begins
 Location of CDJ in the root canal varies
considerably

31.  Generally it is not in the area of apical constriction and
is approximately 1 mm from the apical foramen
 From the apical constriction or the minor apical
diameter canal widens as it approaches AF, or major
apical diameter
 The average size of AF of maxillary teeth in adult is
0.4mm in mandibular teeth slightly smaller being
0.3mm diameter
 The shape between major and minor diameters has
been described as funnel shape or hyperbolic

32.  The AF is not always located at the center of root apex
 It may exit from mesial, distal, labial or lingual surfaces
of root usually slightly eccentrically
 The mean distance between major and minor apical
diameters 0.5mm in young persons and 0.67mm in
older individuals
 Distance is greater in old, because of build of
cementum
 The AF is the circumference or rounded edge, like a
funnel or crater that differentiates termination of the
cemental canal from the exterior surface of root

48. Primary pulp Permanent pulps
Relative volume of pulp is more Relative volume of pulp is less
Pulp horns are more prominent and
are
placed at higher level
Pulp horns are initially prominent but
are
reduced with age and at a lower level
Because of this position of pulp horns
cavity preparation is at a limited depth
Due to lower position of pulp horns
adequate depth is maintained
Accessory canals are frequently found
in the bifurcation areas of molars
Accessory canals are commonly found
in the apical 3rds
The position of apical foramen varies
as they undergo resorption
Position of apical foramen is fixed
Canals are flaring due to flaring roots Canals are usually straight

49.  In young persons pulp horns are long, pulp chambers
are large, root canals are wide, apical foramens are
broad
 With increasing age pulp horns recede, pulp chambers
become smaller in height rather than in width
 Root canals also become narrower due to deposition
of dentin
 Apical foramina also deviate from exact anatomic
apex
 Their minor diameter becomes narrower and major
diameter becomes wider from deposition of dentin and
cementum

50.  Clues in locating extra canals:
 Prominent cingulum of mandibular incisor – an
extra canal may be present lingually
 Prominent lingual cusp of mandibular bicuspid –
an extra canal may be present lingually
 Prominent buccal cusp and wide crown mesio-
distally, a mesial buccal canal or root may be
found in maxillary 1st
premolar

51.  Prominent buccal cusp, wide crown buccolingually
on mesial half in maxillary molar, second mesial
buccal canal be found roof is wider buccolingually
 An extra canal be found in mandibular molar distal
root if distal cusps are prominent

52.  A young permanent usually takes 2-3 years for
completion of root formation after eruption
 So an young permanent tooth posses an immature
apex initially and then matures due to deposition of
dentin and cementum
 If endodontinc intervention is done in these kind of
teeth then treatment varies according to the condition
of pulp
 If radicular pulp is vital then, only coronal pulp is
treated so as to form a physiological and anatomical
mature apex

53.  After apex is matured definite endodontic
treatment is done
 This procedure is referred to as “ apexogenesis”
 If radicular pulp is non-vital and apex is immature,
then both coronal and radicular pulp are treated
an agents will form a definitive barrier between
apical foramen and surrounding tissues should be
applied

54.  Agents such as calcium hydroxide, mineral
trioxide aggregate(MTA), or a mixture of MTA and
paste of camphorated monochlorophenol may
help to form such a definitive barrier
 This kind of procedure is reffered to as
“apexification”
 Certain clinical studies have also shown continued
development of root to form mature apex even
after the raducular pulp is treated

55.  Pulp is only vital that caries blood and nerve
supply as well as nourishes the tooth
 All these features are necessary for the tooth to
respond to and kind of stimulus which will protect
the tooth or alarm the tooth that something is
wrong with the tooth
 If pulp tissue is removed completely, tooth
becomes “non-vital” and hence is insensible to
any kind of stimulus

56.  It is also an organ which when destroyed cannot
be regenerated
 So it is necessary to know the anatomy of the pulp
to carry out any procedures on the tooth and to
make every attempt to save the pulp

57. The dental pulp
Seltzer, Samuel …3rd
ed.
 Endodontic practice
Grossman …5th
ed.
 Endodontics
Ingle …3rd
ed.
 Pathways of pulp
Cohen, Stephan …9th
ed.
 Endodontics
C. Stock, K. Gulabiwala…3rd
ed.
 Endodontic therapy
Weine …6th
ed.