These are the presentation prepared by student of BPKIHS Batch 2015 BDS on observation of respective faculty of BPKIHS

1. Resource Faculties:
Dr. Ashish Shrestha
Dr. Shashi Keshwar
Presented by:
Samiksha Sharma – 705
Sampada Khatiwada-706
30/04/2017

2. CONTENTS
Definition
Repair and regeneration in:
 Enamel
 Dentin
 Pulp
 Cementum

3. Repair
The restoration of tissue function and
architecture following an injury.
Regeneration
The growth and differentiation of new cells from
its precursor cells and intercellular substances to
form new tissues.

4. Repair and Regeneration of Enamel
cannot be reformed once destroyed because of the
degeneration of its precursor cells i.e. ameloblasts
after forming enamel
but capable of some limited repair by physiological
means
if initiated caries is arrested and the enamel surface
has not broken down, supply of calcium and
phosphate ions remineralizes the enamel

5. Repair and Regeneration of Dentin
formation of dentin continues throughout the life
Dental caries, abrasion, attrition or cutting of dentin
during operative procedures lead to its repair and
regeneration
caries attrition Cavity preparation

6. Tertiary Dentin
localized formation of dentin at pulp dentin border in
response to noxious stimuli like caries, trauma,
attrition, cavity preparation, etc.
 no continuity with primary or secondary dentin so
dentin permeability decreases
Quality depends on :
 intensity of stimulus
 vitality of pulp

8. Reactionary Dentin
the exposed or cut
odontoblast cells
survive
continue to form
dentin

9. Reparative Dentin
 dead odontoblasts are replaced by the migration of
undifferentiated cells arising in deeper regions of pulp
to the dentin interface
 newly differentiated mesenchymal cells known as
“Odontoblast like cells” give rise to reparative dentin

11. Reactionary dentin Reparative dentin
Stimulus for
formation
Mild aggressive
Formative cell Surviving
odontoblast
New odontoblast like
cells
Structure Physiologic dentin
Change in direction
of new dentinal
tubules
Heterogeneous
Tubular(organized)
Osteodentin(disorg.)

13. Have enough courage for ending things
before they end up discouraging
you….!!

14. Dead tracts
 Degeneration of odontoblastic process due to caries,
attrition etc. leads the empty dentinal tubules to fill
with air
 In ground section, such tubules appear dark in
transmitted light and white in reflected light
 They demonstrate decreased sensitivity and appear to
a greater extent in older tooth

16. Repair and regeneration of pulp
an organ with remarkable reparative abilities
responds to irritation, whether mechanical, thermal,
chemical, or bacterial, by producing reparative dentin
and mineralizing any affected dentinal tubules
reparative dentin was found to be more atubular in
closed/active lesions
more tubular in open/slowly progressive lesions

17. After injury to the mature tooth, the fate of the
Odontoblast can vary according to the intensity of the
injury
Milder injury can result in functional activity leading
to focal secretion of a reactionary dentin matrix, called
regeneration
Greater injury can lead to Odontoblast cell death;
Induction of differentiation of a new generation of
Odontoblast-like cells can then lead to reparative
dentinogenesis

18. Repair and Regeneration of
Cementum
 serves as the major
reparative tissue for root
surface
 damage to root such as
fracture and resorption
can be repaired by
deposition of new
cementum
 repair may be by the
formation of cellular or
acellular cementum or
both

21. Two types of cementum repair are seen:
Anatomic Repair
 in most cases the repair re-establishes the
former outline of root known as anatomic repair
Functional Repair
 only a thin layer of cementum is deposited on
the surface of deep resorption
 The root outline is not reconstructed and a bay
like recess remains
 the periodontal space is restored to its normal
width by formation of bony projection

22. References:

23. Be careful of things you do,
experiences are good, regrets are
not…!!!!