Brief Explanation on Root canal anatomy and Access Cavity shapes.

2.  Definition : Endodontics is the branch of
dentistry dealing with diseases of the
dental pulp.

3.  The number of canals in a tooth
correlates to the number of roots in a
tooth.
 The space inside the root canals is filled
with a highly vascularized and highly
innervated loose connective tissue,
called the dental pulp.
 The pulp tissue is in communication
with the periodontium and the rest of
the body through the apical foramen.

4.  Central region contains nerves and
blood vessels.
 Innermost layer, - contains fibroblasts
and undifferentiated mesenchymal cells.
 Zone of Weil – This is a cell free zone,
rich in capillaries and nerve fibres.
 Odontoblastic layer – outermost layer,
contains odontoblasts and is next to the
predetin and mature dentin.

5.  Primary Function is to form Dentin
 Nutritive – provides nutrients to the
organic surroundings
 Sensory – sensitive to temperature,
pressure or trauma
 Protective – forms secondary dentin,
when under attack from bacteria.

7.  Accessory canals are branches of the main
canal that form a communication between the
pulp and periodontum.
 They also contain vessels and nerves, and can
be located anywhere between the level of
furcation to the apex.
 30% of lower incisors have lingual and labial
canals.
 85% of mesiobuccal roots contain two canals
(MB1 and MB2), in upper molar teeth.

9. The shape of the preparation is dictated
by :
 The shape of the pulp chamber
 The morphology of the canals.
It is important that straight line access to
the apical foramen is created.

10.  The access cavity is initiated in the
middle of the palatal side of the tooth.
 Initial preparation should be at 90° to
the palatal aspect of the tooth.
 Once dentine has been reached the
angulation of the bur is changed to
follow a long axis of the tooth using a
slow handpiece.

11.  Initial preparation is made in the
middle of the fissure. The cavity is then
extended buccally and palatally.
 NB : Marginal ridges must not be
involved in this presentation, as this
would compromise the integrity of the
tooth.

12.  Initial Preparation is done in the mesial
pit.
 The cavity is then extended in the mesial
half of the tooth to include all canals.
 The mesial marginal ridge must not be
damaged in upper molars as the cavity
should lay mesially to it.
 However lower molar teeth, have a distal
canal, which is located just past the middle
of the tooth.

16. Irrigation in Endodontic treatment
serves the following purposes:
 Lubricate canal
 Dissolve the pulp remnants
 Washing out debris created by canal
instrumentation
 Kill/remove the bacteria/micro-
organisms in root canal
 Clean the smear layer

17.  Sodium Hypochlorite :Dissolves necrotic
tissue and kills bacteria quite effectively.
 Kills bacteria quite effectively.
 Chelators: Such as EDTA, remove the
smear layer.
 Hydrogen Peroxide: Used to be used a lot,
however studies have shown it to be
ineffective.
 Chlorhexidine: Has been shown to remove
significant number of bacteria.

18.  ENDOVAC TECHNOLOGY – the use of
apical negative pressure irrigation,
significantly improves cleaning and
disinfection more closely to the apex.
 ENDOACTIVATOR – Sonically driven
system, enables the irrigant to travel
deep into the pulpal system, enabling
better cleaning.

19.  Tooth Anatomy – Revision
 Root canal anatomy
 Accessory canals
 Access cavities
 Irrigants
 Recent Developments in Endodontics.

20.  http://www.dentistrytoday.com/endodon
tics/1043
 http://www.youtube.com/watch?
v=QrUgCNQs038
 Endodontics Lecture from Blackboard.
By Dr Qualtrough.
 http://www.dentistrytoday.info/content/i
rrigation-endo
 http://www.jendodon.com/article/S0099-
2399(07)00095-7/abstract