2. The equipment necessary for the administration of
local anesthetics and for the extraction of the tooth
introduced in armamentarium
Armamentaria have evolved to ease surgery
,shortening on table time, widening the surgical
field, increasing visibility,mimimizing trauma to
surgical areas etc
3. OBJECTIVES
To provide an optimal surgical field
For optimum visibility
To decrease physical strain of the surgeon
To enable patient comfort
To protect vital structures
5. ADA CRITERIA FOR ACCEPTANCE OF LOCAL
ANESTHETIC SYRINGE
1. they must be durable and able to withstand
repeated sterilization without damage
2. they should be capable of accepting a wide
variety of cartridge and needles of different
manufacture and should permit repeated use
3. inexpensive , self-contained , lightweight and
simple to use with one hand
4. they should provide for effective aspiration and
be constructed so that blood may be easily
observed in the cartridge
6. I. SYRINGE
It is the vehicle whereby the contents of the anesthetic
cartridge are delivered through the needle to the patient.
Four types:
1. Nondisposable syringes:
a. Breech-loading , metallic , cartridge-type ,
aspirating
b. Breech-loading , plastic , cartridge-type ,
aspirating
c. Breech-loading , metallic , cartridge-type ,
self-aspirating
d. Pressure syringe for periodontal ligament injection
e. Jet injector (needle-less syringe)
2. Disposable syringe
3. Safety syringes
4. Computer-controlled local anesthetic delivery systems
7. 1. NONDISPOSABLE SYRINGES
o A. Breech-loading metallic cartridge type
aspirating syringe
- most commonly used in dentistry
- breech loading implies that the cartridge is
inserted into the syringe from the side of the
barrel of the syringe
- the needle is attached to barrel of the syringe
at the needle adaptor
- the needle than passes into the barrel, where
it penetrates the diaphragm of local
anesthetic cartridge
- the needle adaptor is removable and sometimes is
discarded inadvertently along with disposable needle
8.
9. METALLIC BREECH-LOADING , ASPIRATING
SYRINGE........
Advantages
- visible cartridge
- aspiration with one
hand
- autoclavable
- rust resistant
- long lasting with
proper maintenance
Disadvantages
- weight(heavier than
plastic syringe)
- syringe may be too big
for small operators
- possibility of infection
with improper care
10. B. Breech-loading , plastic , cartridge-type
aspirating syringe
- a plastic, reusable, dental aspirating syringe
is available that is both autoclavable and
chemically sterlizable
- with proper handling, this syringe may be
used for multiple anesthetic administrations
before it is discarded
11. PLASTIC, REUSABLE, ASPIRATING
SYRINGE.........
Advantages
- plastic eliminates
metallic,clinical look
- lightweight: provide
better feel during
injection
- cartridge is visible
- aspiration with one hand
- rust resistant
- long lasting with proper
maintenance
- low cost
Disadvantages
- size(may be too big for
small operators)
- possibility of infection
with improper care
- deterioration of plastic
with repeated autoclaving
12. C. Breech-loading , metallic , cartridge-type , self-
aspirating syringe
- to increase ease of aspiration , self-aspirating
syringes have been developed
- these syringes use the elasticity of the rubber
diaphragm in the anesthetic cartridge to
obtain the necessary negative pressure for
aspiration
- the use of a self-aspirating dental syringe
permits easy performance of multiple
aspirations throughout the period of local
anesthetic deposition
13.
14. METALLIC , SELF-ASPIRATING SYRINGES.......
Advantages
- cartridge visible
- easier to aspirate with
small hands
- autoclavable
- rust resistant
- long lasting with proper
maintenance
- piston is scored(indicates
volume of local
anesthetic administered)
Disadvantages
- weight
- feeling of insecurity for
doctors accustomed to
harpoon-type syringe
- finger must be moved
from thumb ring to thumb
disc to aspirate
- possibility of infection
with improper care
15. D. Pressure syringes
- it is brought about a renewed interest in the
periodontal ligament injection
- it is also known as intraligamentary injection
- it is more reliable to achieve pulpal anesthesia of
one isolated tooth in mandible
18. E. Jet injector
- jet injection is based on the principle that
liquids forced through very small openings ,
called jets , at very high pressure can
penetrate intact skin or mucous membrane
- the most frequently used jet injectors in
dentistry are syriJet Mark II and MadaJet
- the primary purpose of the jet injector is obtain
topical anesthesia before insertion of a needle
19.
20. JET INJECTORS.......
Advantages
- does not require use of
needle
- delivers very small
volumes of local
anesthetics
- used in instead of
topical anesthetics
Disadvantages
- inadequate for pulpal
anesthesia or for
regional block
- some patients are
disturbed by the jolt of
the injection
- cost
- may damage
periodontal tissue
21. 2. DISPOSABLE SYRINGES
Most often they are used for intramuscular or
intravenous drug administration, but they also may
be used for intraoral injection.
These syringes contain a luer-lock screw on needle
attachment with no aspirating tip.
Because there is no thumb ring aspiration ,it
requires both hands.
In addition this syringes do not accept dental
cartridges.
22.
23. DISPOSABLE SYRINGE........
Advantages
- disposable, single use
- sterile until opened
- lightweight
Disadvantages
- does not accept
prefilled dental
cartridges
- aspiration difficult
24. 3. SAFETY SYRINGES
Safety syringes minimize the risk of an accidental
needle-stick injury occurring to a dental health
provider with a contaminated needle after
administration of a local anesthetics
These syringes possess a sheath that “locks” over
the needle when it is removed from the patient’s
tissues , preventing accidental needle-stick
These are designed as single-use items , although
they permit reinjection
25.
26. SAFETY SYRINGES......
Advantages
- disposable , single use
- sterile until opened
- lightweight
Disadvantages
- cost: more expensive
than reusable syringe
- may feel awkward to a
first-time user
27. 4. COMPUTER-CONTROLLED LOCAL
ANESTHETIC DELIVERY(C-CLAD) SYSTEMS
This system enables a dentist or hygienist to
accurately manipulate needle placement with
finger-tip accuracy and deliver the local anesthetic
with a foot-activated control
28.
29. RECOMMENDATIONS
1. A safety syringe, minimizing the risk of accidental
needle-stick injury, is recommended for use during
all local anesthetic injections
2. A self-aspirating syringe is recommended for
practitioners with small hands
3. All reusable syringes must be capable of being
sterilized
4. Nonreusable syringes must be disposed of
properly
5. Non-aspirating syringes should never be used for
local anesthetics
30. II. NEEDLE
Needle is a vehicle that permits local anesthetic
solution to travel from the dental cartridge into the
tissues surrounding the needle tip
Most needles used in dentistry are stainless-steel
and disposable
31. PARTS OF NEEDLE
Bevel
Shaft
Hub
Syringe adaptor
Cartridge penetration end
32. GAUGE
Gauge refers to the diameter of the lumen of the
needle: the smaller the number , the greater the
diameter of the lumen
A 30-gauge needle has a smaller internal diameter
than 25-gauge needle
There is a growing trend toward the use of smaller
diameter needles based on the assumption that
they are less traumatic to the patient than needles
with larger diameter
The most commonly used needles in dentistry are
30-gauge short and 27-gauge long
33.
34. ADVANTAGES OF LARGER NEEDLE OVER
SMALLER GAUGE NEEDLE
1. Less deflection , as needle advances through
tissues
2. Greater accuracy of injection
3. Less chance of needle breakage
4. Easier aspiration
5. No perceptual difference in patient comfort
35. LENGTH
Dental needles are available in three lengths:
Long : 30-35mm
Short : 20-25mm
Ultra-short : <20mm
36. RECOMMENDATIONS
1. Sterile disposable needles should be used
2. If multiple injections are to be administered,
needles should be changed after three or four
insertions in a single patient
3. A needle should never be forced against
resistance
4. Needles should remain capped until used and
should be made safe immediately when withdrawn
5. The direction of a needle should not be changed
while it is still in tissue
37. III. CARTRIDGE
The dental cartridge is a glass cylinder containing
the local anesthetic drug , among other ingredients
39. PROBLEMS
1. Bubble in cartridge
2. Extruded stopper
3. Burning on injection
4. Sticky stopper
5. Corroded cap
6. Rust on the cap
7. Leakage during injection
8. Broken cartridge
40. RECOMMENDATIONS
1. Dental cartridges must never be used on more
than one patient
2. Cartridges should be stored at room temperature
3. It is not necessary to warm cartridge before use
4. Cartridges should not be used beyond their
expiration date
5. Cartridges should be checked carefully for cracks,
chips, and the integrity of the stopper and cap
before use