This document discusses infection control in orthodontics. It describes the main pathways for cross-contamination between patients and dental staff, as well as the most important pathogens including hepatitis B virus, HIV, and herpes simplex virus. Proper sterilization of orthodontic instruments and use of personal protective equipment are essential to control cross-infection in the dental office.
3. Introduction
X-rays are a form of electromagnetic radiation
Ability to ionize matterwhich is the initiating
event in radiation induced biologic changes
www.indiandentalacademy.com
4. RADIATION BIOLOGYRADIATION BIOLOGY
IS THE STUDY OF THE EFFECTS OF
IONIZING RADIATION ON THE LIVING
SYSTEM.
Deterministic Stochastic
Severity of response probability of a
proportional to dose response occur
www.indiandentalacademy.com
5. RADIATION CHEMISTRYRADIATION CHEMISTRY
Free radical production
RH + Photon R + H+
+ e
These free radicals are unstable ,short lived and highly
reactive.
Fate of the free radical _
1) Dissociation
R X + Y
2) Cross linking
R + S RS
www.indiandentalacademy.com
6. thus there is formation of structurally and
functionally biologic molecules differing from
original molecule.there by inducing biological
change.
www.indiandentalacademy.com
7. Radiation acts on living system either
DIRECT INDIRECT
Direct ionization of biologic photon absorbed by
H2O
macromolecules with H2O IONIZED
formation of unstable free
radicals. Resultant free
radical
interact and
change the
macro moleculewww.indiandentalacademy.com
8. Radiosensitvity and cell typeRadiosensitvity and cell type
Most radiosensitive cells are are
1)undergoing mitoses
2)having a high mitotic rate
3)are most primitive in differentiation
www.indiandentalacademy.com
9. Cells are usually divided into five categories of
radiosenstivity
1)vegetative inter mitotic cells
2)differentiating inter mitotic cells
3)multipotential connective tissue cells
4)reverting post mitotic cells
5)fixed post mitotic cells
www.indiandentalacademy.com
10. )vegetative intermitotic cells—most radiosensitive
Eg:precursor cell–
spermatogenicerythoblastic ,basal cells of the oral
mucous membrane.
2)differentiating intermitotic cells –Eg: intermediate
cells of hemapoietic ,replicating cells of the inner
enamel epithelium
www.indiandentalacademy.com
11. Multi potential connective tissue cells –
---Eg intermediate radio sensitivity
--- : endothelial cells,fibroblasts
Reverting post mitotic cells ---radio resistant
---Eg: acinar and ductal cells of salivary gland and
pancreas,parenchymal cells of liver ,kidney and
thyroid
Fixed post mitotic cells---most radioresistant
---Eg:neurons ,striated muscle cells ,squamous cells
close to the surface of oral mucous membrane and
erythocytes
www.indiandentalacademy.com
12. High Intermediate Low
Lymphoid Fine vasculature Optic lens
Bone marrow Growing cartilage Mature
Growing bone eryhtocytes
Intestines Salivary glands Muscle
Mucous Lungs cells
membrane Kidney Neurons
Liver
Relative Radio sensitivityRelative Radio sensitivity
of Various Organsof Various Organs
www.indiandentalacademy.com
14. Radiation effects may be spoken In terms :-
the short term effects which bring about …
mitosis linked cell death
the long term effects that bring about….fibro
atrophic cell death
www.indiandentalacademy.com
15. Short term effectsShort term effects
Primarily determined by the sensitivity of the
parenchymal cells of the respective
tissue
Raidly proliferatingcell loss mitosis linked
reduction in the number of mature cells .
In tissues that undergo little proliferation the
radiation induced hypoplasia is not evident
www.indiandentalacademy.com
16. Long Term EffectsLong Term Effects
Determined by the extent of damage to the
fine vasculature of the tissue
Endothelial cells---multi potential
connective tissue cells---intermediate radio
sensitivity..
Thus over a period of time ---capillaries
,degenerate and undergo necrosis.
Permeability increased
www.indiandentalacademy.com
17. progressive fibrotic processes begins
around the capillaries
This fibrotic scar tissue will eventually
cause obliteration of blood vessels---
depriving the cells of nutrition ,oxygen
and elimination of waste
Eventually leading to loss of cell function
,decreased resistance to infection and death
of all cell types…with the net result of
PROGESSIVE FIBROATROPHY
www.indiandentalacademy.com
20. • Oral mucous membrane
* Short term effects –related to the radiosensitive
vegetative intermitotic cells of the basal layer of the
mucous membrane.
* Initially —redness and inflammation—mucositis
*as therapy continues – formation of whitish yellow
pseudomembrane—desquamated epithelial layer
*2 months after therapy—rapid healing---
• mucosa becomes atrophic,thin relatively
avascular.
www.indiandentalacademy.com
21. Taste budsTaste buds
*are radiosensitive—extensive degeneration
*loss of taste acuity during second or third
week of radiotherapy
*recovery usually takes between 60-120 days
www.indiandentalacademy.com
22. Salivary glandsSalivary glands
The parenchymal component of salivary glands is
radiosensitive
Short-term effects –inflammatory response
Long-term effect progressive fibrosis,adiposis,loss
of fine vasculature with parenchymal
degeneration---accounting for xerostomia.
Marked reduction of salivary flow is seen in the
1st
two weeks
Xerostomia ,decreased ph of saliva (6.5to 5.5)---
this is low enough to cause decalcification
Buffering capacity falls by 44%www.indiandentalacademy.com
23. Flora thus becomes more acidogenic in
saliva and plaque ---this along with thick
viscous ,acidic saliva---renders patient
susceptible to radiation caries. Oral micro
flora changes –strept.mutants,lactobacillus
and candidasis
Recovery—6 to 12 months
If not –unlikely that there will be significant
recovery
www.indiandentalacademy.com
25. Radiation cariesRadiation caries
Rampant form of decay
Irradiation of the teeth does not influence the
decay but the changes induced in the salivary
glands and saliva are responsible for this decay
There are three types of radiation caries
-----superficial lesions—B,O,Li,P surfaces
-----primarily involving cementum and dentin
in the cervical region
-----dark pigmentation of the entire crown
www.indiandentalacademy.com
26. Reducing ----daily application for 5 minutes
of a viscous topical 1% neutral NaF gel
--------avoidance of dietary sucrose
www.indiandentalacademy.com
28. TeethTeeth
Severity of damage is dose dependent
If irradiation precedes calcification –tooth bud
destroyed
After calcification has begun—inhibition of
cellular differentiation –malformations and
arresting growth
Adult teeth are relatively radioresistant
Pulpal tissue –reverting and fixed postmitotic cells
—may show long –term fibroatrophy
No discrenible effect on the crystalline structure of
enamel ,dentin or cementumwww.indiandentalacademy.com
29. BoneBone
Primary damage—results from damage to
the vasculature of the periosteum and
cortical bone
Also the radiation tends to destroy
osteoblasts and to a lesser extent osteoclasts
Bone marrow fatty bone marrow and
fibrous connective tissue
marrow hypo vascular,hypoxic and
hypo cellular
Degree of mineralization reduced brittle
www.indiandentalacademy.com
31. OsteoradionecrosisOsteoradionecrosis
Decreased vascularity -renders bone
susceptible to infections
Source of these infections may be from
radiation –induced breakdown of the oral
mucous membrane ,mechanical damage
tooth extraction ,denture sore,PD lesion
or radiation caries...
Mandible > maxilla
www.indiandentalacademy.com
33. Relevance of Radiation inRelevance of Radiation in
OrthodontiaOrthodontia
• Most commonly taken radiographs in
Orhtodontia are :-lateral cephalogram
panoramic radiograph
• hand- wrist x-rays
• Exposure of critical organs which are:-
active bone marrow
thyroid gland
salivary glands
optic lenswww.indiandentalacademy.com
34. Exposure is of low doses …example for the
formation of cataract 2Sv(200 rem)but in opg
dose exposed to in the form of scattered radiation
is only 80 microSv
Also studies by Danforth and Gibbs
Thyroid160-370 microGys
Pitutary 70-490 microGys
Salivary glands 393 microGys
As these doses are well below the maximum
permissible dose the harmful effects still remain
uncertain
www.indiandentalacademy.com
35. Harmful effects manifest as increased
probability of a normally occurring disease
Bear in mind ALARA principle
www.indiandentalacademy.com
36. Maximum Permissible DoseMaximum Permissible Dose
Two categories :-ouupationally exposed
Non occupationally exposed
Whole body Isolated areas of
body
Occ.exp. 0.05Svyear 0.75Svyear
Non occ. 0.005Svyear 0.075Svyear
Exp.
www.indiandentalacademy.com
38. Patient protection
1) Intensifying screens
2) Focal spot to film distance
3) Collimation
4) Filtration
5) Lead aprons and collars
6) Good radiographic techniques
www.indiandentalacademy.com
39. Protection of PersonnelProtection of Personnel
Barrier/position and distance rule
Operator never hold film
Personnel should wear film badges
Regular checks of x-ray equipment for
spills
www.indiandentalacademy.com
40. IS A COLLECTION OF SIGNS AND
SYMPTOMS EXPERIENCED BY PERSONS
AFTER ACUTE WHOLE BODY EXPOSURE
TO RADIATION
1)Prodromal Period
2)Hematopoietic Syndrome
3)Gastrointestinal Syndrome
4)Cardiovascular Syndrome
Acute Radiation SyndromeAcute Radiation Syndrome
www.indiandentalacademy.com
41. PRODROMAL PERIODPRODROMAL PERIOD
WITHIN FIRST MINUTES TO HOURSAFTER
EXPOSURE ,SYMPTOMS OF
GASTROINTESTINAL TRACT
DISTURBANCES MAY OCCUR.
ANOREXIA,NAUSEA
VOMITTING,DIARRHEA,WEAKNESSAND
FATIGUE
SEVERITY AND TIME OF ONSET R DOSE
RELATED
www.indiandentalacademy.com
43. HEMATOPOIETIC SYNDROMEHEMATOPOIETIC SYNDROME
2 TO 7 Gy CAUSES INJURY TO THE
HEMATOPOETIC STEM CELLS OF THE
BONE MARROW AND SPLEEN.
FALL IN THE NUMBER OF
CIRCULATING
GRANULOCYTES’PLATELETS,AND
ERTHROCYTES.
www.indiandentalacademy.com
44. THE CLINICAL SIGNS OFTHE CLINICAL SIGNS OF
THE HEMATOPOIETICTHE HEMATOPOIETIC
SYNDROME INCLUDE-SYNDROME INCLUDE-
1)INFECTION-LYMPHOPENIAAND
GRANULOCYTOPENIA
2)HEMORRHAGE—
THROMBOCYTOPENIA.
3)ANEMIA—ERYTHOCYTE
DEPLETION
IF PATIENT DOES NOT RECOVER DEATH
MAY OCCUR IN 10 TO 30 DAYS.
www.indiandentalacademy.com
45. GASTROINTESTINALGASTROINTESTINAL
SYNDROMESYNDROME
7 to 15 Gy causes extensive damage to the rapidly
proliferating epithelial cells of the intestinal villi
with resultant –denudation of mucosal surface
,loss of plasma and electrolytes
these changes are responsible for
diarrhea,dehydration,and weight losses well
as invasion of endogenous intestinal bacteria
producing septicemia.
www.indiandentalacademy.com
46. These damages along with the hematopoietic
damage together contribute to the signs and
symptoms of GASTROINTESTINAL
SYNDROME
www.indiandentalacademy.com
47. CARDIOVASCULAR AND CENTRALCARDIOVASCULAR AND CENTRAL
NERVOUS SYSTEM SYNDROMENERVOUS SYSTEM SYNDROME
Exposure to a dose in the range of 50Gy will
cause death in a few minutes to 2 days
There is collapse of the cardiovascular
system and autopsies reveal necrosis of the
cardiac muscle .
Damage to the nervous system manifests as
patient showing intermittent stupor ,inco-
ordination,disorientation and convulsions
www.indiandentalacademy.com
49. ContentsContents
Introduction
Mechanisms of Cross Infection
Important Pathogens in Infection Control
Control of Cross-Infection
Sterilization in Orthodontics
www.indiandentalacademy.com
50. Pathways for Cross-Contamination
Patient to dental team
Dental team to patient
Patient to patient
Dental office to
community
Modes of disease spread :-Direct contact
Indirect contcat
Droplet infection
IntroductionIntroduction
www.indiandentalacademy.com
51. Mechanism or site of entry into
body:-
through breaks in
skinmucous membrane
through inhalation
www.indiandentalacademy.com
53. There are several important disease in
infection control but the ones of most
significance in the dental office are:-
Hepatitis B virus
HIV
Herpes Simplex Virus
www.indiandentalacademy.com
54. Infectious agent Disease or condition Route of
transmission
Incubation period Communicable
period
Hepatitis A virus ‘Infectious hepatitis’
Type A Hepatitis
Feco-oral, Food ,
water, shellfish
2 to 6 wks (av. 28
to 30 days)
2 to 3 wks before
onset (jaundice)
through 8 days
after
Hepatitis B Virus ‘Serum hepatitis’ Type
B Hepatitis
Blood, saliva, body
fluids,sexual
contact, perinatal
2 to 6 months ( av.
60 to 90 days )
Before, during &
after clinical signs
Carrier state:
indefinite
Delta Hepatitis
Virus ( HDV )
Delta Hepatitis Coinfection with
HBV, Blood,
Sexual contacts,
Perinatal
2 to 10 weeks All phases
Non-A, Non-B
Hepatitis Virus
Non-A, non-B hepatitis Similar to HBV 2 to 6 months Like HBV
Epidemic non-A non-B Feco-oral
Contaminated
water
15 to 64 days Not known. Maybe
like HAV
Human
Immunodeficienc
y Virus ( HIV )
Acqired
Immunodeficiency
Syndrome ( AIDS )
Blood & blood
products
( infected i.v
needles ), sexual
contact, perinatal,
3 months to 5
years
2 years for
transfusion case )
From
asymptomatic
through onset of
opportunistic
infections
www.indiandentalacademy.com
55. Herpes Simplex
Virus
Type I ( HSV -1 )
Type II (HSV-2 )
Acute Herpetic
gingivostomatitis
Herpetic labialis
Ocular herpetic
infections
Herpetic Whitlow
Saliva, direct
contact ( lip, hand )
Indirect contact
(on objects, limited
survival)
Sexual contact
2 to 12 days Labialis: one day
before onset until
lesions are crusted
Acute stomatitis:
7wks after
recovery
Asymptomatic
infection: with viral
shedding
Reactivation
period: with viral
sheddingVaricella-zoster
virus (VZV)
Chickenpox
Shingles
Direct contact
Indirect contact
Airborne droplet
2 to 3 weeks 5 days prior to
onset of rash until
crusting of vesicles
Epstein- Barr Virus
( EBV )
Infectious
mononucleosis
Direct contact
Saliva
4 to 6 weeks Prolonged
Pharyngeal
excretion 1yr after
infection
Cytomegalovirus
( CMV )
Neonatal CMV
infection
CMV disease
Perinatal
Direct
contact(most body
secretions)
Blood transfusion
Inexact
3 to 8wks after
transfusion
Months to years
www.indiandentalacademy.com
56. Treponema
pallidum
Syphilis Direct contact
Transplacental
10 days to 10 weeks Variable and
indefinite
Maybe 2 to 4 years
Neisseria
gonorrhoea
Gonorrhea Direct contact
Indirect contact
(short survival of
organism)
2 to 9 days During incubation
Continued for
monthsand years if
untreated
Group A
streptococci
(Beta-hemolytic)
Streptococcus
pyogenes
Streptococcal sore
throat
Scarlet fever
Impetigo
Erysipelas
Respiratory
droplets
Direct contact
1 to 3 days 10to 21 days,
untreated
Many nasal
oropharyngeal
carriers
Staphylococcus
aureus
Staphylococcus
epidermidis
Abscesses
Boils (furuncles)
Impetigo
Bacterial
pneumonia
Saliva
Exudates
Nasal discharge
4 to 10 days
Variable and
indefinite
While lesions drain
and carrier state
persists
www.indiandentalacademy.com
57. Influenza
viruses
Influenza Nasal discharge
Respiratory
droplets
24 to 72 hrs 3 days from
clinical onset
Measles Virus
(Morbilivirus)
Rubeola (measles) Direct contact
Saliva
Airborne droplets
8 to 13 days to
fever, 14 days to
rash
Few days before
fever to 4 days
after rash appears
Rubella virus
(Togavirus)
Rubella (German
measles)
Nasopharyngeal
secretions
Dirrect contact
Airborne droplets
16 to 23 days From 1wk to at
least 4 days after
rash appears
Congenital Rubella
Syndrome
Maternal infection,
first trimester
Infants shed virus
for months after
birth
Mumps virus
(Paramyxovirus
)
Infectious parotitis Direct contact
(saliva)
Airborne droplets
2 to 3 wks
(average 18 days)
From 1 to 7 days
before sympoms
until 9 days after
swelling
Polio virus
types 1,2,3
Poliomyelitis Direct contact
(saliva), Droplet,
Feco-oral
7 to 14 days Probably most
infectious 7 to 10
days before and
after onset of
symptoms
Mycobacteriu
m Tuberculosis
Tuberculosis Droplet nuclei
Sputum
Upto 6 months Long, repeated
exposure usually
www.indiandentalacademy.com
59. An infection-control program comprises two distinct
areas: exposure control and hazard
communication.
Exposure control covers sterilization and disinfection,
waste management, and employee including personal
protective equipment and bodily-fluid-exposure
protocols.
Hazard communication requirements include a periodic
checklist for OSHA compliance, drills for hazard
communication plans (chemical spills, emergency first
aid, and fire or tornado evacuation), secondary labeling of
hazardous chemicals, Material Safety Data Sheets, x-ray
updates, and properly displayed state and federal posters.www.indiandentalacademy.com
60. TerminologiesTerminologies
Sterilization it is the process of destroying all
forms of microbial life
Disinfection it is defined as the removal of or
inactivation of microbes.thus it implies only some
and not all pathogenic organisms can be
eliminated by this method.
Anti-septicsthese are substances that prevent
the growth or action of microbes by either
destroying them or inhibiting their actions
www.indiandentalacademy.com
61. Sanitizersreduce the microbial population to
safe levels as judged by public health
requirements.they are usually chemical agents that
kill close to 99.9%of the organisms.
Germicideskill the growing forms but not
necessarily the resistant spores.
Bacterio static agents agents which have the
ability to inhibit he growth of bacteria.
www.indiandentalacademy.com
62. SterilizationSterilization
Is a process intended to kill all
microorganisms whether vegetative or
pathogenic .
It is the highest level of microbial killing
that can be achieved
www.indiandentalacademy.com
63. The protocol for sterilization of instruments
is usually
1)holdingpresoaking
2)pre cleaning
3)sterilization process
4)aseptic storage and handling of
instruments
www.indiandentalacademy.com
64. Holding PresoakingHolding Presoaking
If instrument not to be cleaned immediately
soak in holding solution prevents
salivablood from drying up.
Holding solution usually is a germicidal
Discard solution at least once a day
Avoid prolonged soakingcorrosion
www.indiandentalacademy.com
65. Pre cleaningPre cleaning
Reduces amount of microbes present ,but
more importantly removes blood saliva and
other materials that may insulate microbes
from the sterilizing agent.
May be achieved by
ultrasonic
manual
www.indiandentalacademy.com
66. Sterilization ProcessSterilization Process
A) Physical agents
B) Sunlight
C) Dry heat:-
flaming
incineration
hot air
D) Moist heat :
boiling
steam under pressure
E) Filtration:-
membranes
asbestos padswww.indiandentalacademy.com
68. In dentistry the procedures used are:-
1)Heat sterilization
2)Gaseous sterilization
3) Liquid chemicals sterilization
www.indiandentalacademy.com
69. Heat sterilizationHeat sterilization
a) Moist heat:-steam pressure autoclave
b) Unsaturated chemical vapour:- chemiclave
c) Dry heat:- conventional dry heat ovens
:- short cycle high temperature dry
heat ovens
www.indiandentalacademy.com
70. Steam Pressure AutoclaveSteam Pressure Autoclave
Sterilizes by bringing about oxidation as well as
denaturing proteins
It is the latent heat and not the pressure built
inside by steam within the closed chamber that is
responsible for killing of the microbes
Two cyclesStandard..20 –30 mins.at 250°f
Flash cycles..3-10 mins.at 273°f
www.indiandentalacademy.com
72. Unsaturated Chemical vaporUnsaturated Chemical vapor
Chemical solution heated in a closed
solution-chemical vapor kills the
microbes
0.23%formaldehyde,72.38%ethanol along
with acetone,ketone and water
20 min at 270°f
www.indiandentalacademy.com
73. Advantages
1)eliminates or reduces the corrosion of
susceptible instruments.
2)dry instruments available at end of cycle
Disadvantages
1)items sensitive to elevated temp.will get
damaged
2)pre drying of inst.a must
www.indiandentalacademy.com
75. Dry HeatDry Heat
Conventional dry heat ovens
*heat chambers wherein heated air is circulated by
gravity convection
*320f for 30 min
*place packs at least 1 cm apart to allow for the hot
air to circulate between wrapped instruments
www.indiandentalacademy.com
77. Short –cycle high temperature dry heat
ovens
Are force draft ovens
370°f to 375°f for 6 to 12 mins
Advantages :-1)instruments sensitive to
corrosion may be safely sterilized
2)effective rapid cycles are possible
3)items dry at end of cycle
www.indiandentalacademy.com
78. Disadvantage
Instruments sensitive to elevated temp. will get
damaged
Ethylene oxide sterilization
for complex, delicate , heat sensitive inst.
aeration of about 24hours must pror to use
of instruments especially porous and plastic
ones
www.indiandentalacademy.com
80. Boiling waterBoiling water
Even though seen to be used commonly it
does not kill spores and does not bring
about sterilization of instruments
Heat reaches and kills the blood borne
pathogens
100° for 10 min.
Thus more than sterilization it is a process
of high level disinfections
www.indiandentalacademy.com
83. Chemical MethodsChemical Methods
Chemical agents are used for controlling of
microbes on body surfaces and on
inanimate objects are grouped under
disinfectants
These includeantiseptics
sanitizing
degerming
disinfecting agents
www.indiandentalacademy.com
84. Qualities of a universalQualities of a universal
disinfectantdisinfectant
1)destroy all forms of microorganisms
within a practical period of time
2)non-toxic,non-allergic,non-irritating
3)non-corrosive,non-discolouring ,non-
degrading
4)good wettability and penetrabilityfor
effective contact even in the presence of
blood and exudate
5)readily soluble in available solvents
www.indiandentalacademy.com
85. ClassificationClassification
Spaulding in 1972
A. High level disinfectants
Eg:-ethylene oxide gas,immersion
glutheraldehyde solutions
B. Intermediate level disinfectants
Eg:-formaldehyde ,chlorine
compounds,alochol,iodophors ad phenolic
compounds
www.indiandentalacademy.com
87. Categories of chemicalCategories of chemical
disinf.disinf.
A) Alcohols
B) Aldehydes
C) Halogens
D) Surfactants
E) Quanternary ammonium compounds
F) Phenols and Phenolic compoundwww.indiandentalacademy.com
88. A. Alcohols
bactericidal and fungicidal but not
sporicidal
MOA :- denature proteins
solvent action on lipids
Ethyl and isopropyl alcohols…most
commonly used
optimum conc. 70% range 60-95%
If conc.falls below 45%antmicrobial
activity is slow and uncertain
www.indiandentalacademy.com
89. Alkalating agents
Formaldehyde
Gaseous state …used as a fumigant
MOA :- protoplasmic poison
denaturing proteins
Disadvantage:-pungent odour
,irritating t skin ,poor penetrating and
slow acting
www.indiandentalacademy.com
90. Gluteraldehyde :-
less pungent volatile and irritating with
better disinfectant properties
broad spectrum of
activity2%sol.bactericidal,tubercu
locidal and virucidal in 10 mins and
sporicidal in 10 hours
gluteraldehyde+iodine comp.+bleach
recommended for use against Hb virus
where sterilization not feasible
www.indiandentalacademy.com
91. They also have a low surface tension
and can thus penetrate blood and
exudate thus reaching instruments
surfaces
Also used for disinfection of
impressions
Cidex , sporicidin, glutorex
www.indiandentalacademy.com
94. Chlorine
Sanitizing agent
Elemental chlorine used for water
purification
may also be used as a surface
disinfectant
conc. 2.5%
gloves must be worn
corrosive to metals
www.indiandentalacademy.com
95. Iodine :- used for wound and skin
antisepsis
Tinctures of iodine are usually used in
1,5and 7% conc. Which destroy 90%of
bacteria in 90,60 and 15 sec.
respectively
• Iodophors:- composed of complexes
of iodine and surface active organic
carrier molecules from which iodine
gradually released .
www.indiandentalacademy.com
97. Phenols :-
As disinfectants and antiseptics
MOA:-denaturing of proteins or damage to cell
membrane
Bacteroicidal and bacteriostatic…but poor
viricidal properties
www.indiandentalacademy.com
99. These include :-
Gloves
Mouth masks
Protective eyewear
Hand washing
Immunization
www.indiandentalacademy.com
100. GlovesGloves
The need for gloving
The practices of gloving not only
provides protection to dentist but also to
the patient
www.indiandentalacademy.com
102. Patient Care GlovesPatient Care Gloves
Disposable gloves
Do not wash gloves with detergents in an attempt
to reuse
While leaving chairside remove gloves
While working chair side try and put to use the
practice of double gloving
www.indiandentalacademy.com
104. Protective EyewearProtective Eyewear
Protection from microbes
Eg:HSV, Hepatitis B
Protection against physical damage
Protection from impact damage
Protection from splashes of chemicals
www.indiandentalacademy.com
105. Preferable to use goggles over glasses as
former not only provides protection from
front splash and impacts but also from side
impacts and splashes
www.indiandentalacademy.com
106. Hand washingHand washing
Two types of micro flora
resident flora
transient flora
www.indiandentalacademy.com
107. Resident flora:colonize and become
resident
can never be completely
eliminated
less imp. In causing
disease
www.indiandentalacademy.com
108. Transient flora:acquired whilst dealing
with contaminated objectssurfaces
do not colonize or
survive for long periods on the hand
usually pathogenic
can be removed by
following a good hand washing protocol
www.indiandentalacademy.com
109. Hand washing products containing low
levels of microbial agents used in a 10 –30
sec.hand wash routine minimizes the no.of
transient flora and aids in reducing the no.of
resident flora too.
Chlorhexidine digluconate ,povidine
iodine,parachlorometaxylonol
Washing of hands before and after gloving
very imp.
www.indiandentalacademy.com
111. MasksMasks
Protect mucous membrane of mouth and
nose from contact with
aerosolssprayssplashes of oral fluids from
patients…also in turn protect patient
Composed of material that filters out 95%-
99.9%of 2-3 micrometer size particles that
directly contact it
They should be form-fitting over the bridge
of the nose to reduce fogging of eyewear
www.indiandentalacademy.com
112. Dispose mask once it gets moist
resistance to airflow through the mask
increasesmore unfiltered air is allowed to
pass by the edge of the mask
Use disposable maskschanging between
patients
www.indiandentalacademy.com
113. ImmunizationImmunization
Hepatitis
The HBV is an infectious agent associated
with acute and chronic hepatitis .
Major cause of necrotizing vasclitis,cirrhosis ,
and primary hepatocellular carcinoma.
Found primarily in blood and blood products
…may also be present in other body
fluids…saliva , semen,tears,urine
www.indiandentalacademy.com
114. Transmitted parenterally,sexual
contact,mother to fetus
HBV relatively environmentally stable…
potential for indirect transmission via
contact with contaminated inst.
Best protection is by immunization
Two vaccines Recombivax HB and
EngerixB
Regime :-1.0ml doses given at 0, 1, and 6
mths
www.indiandentalacademy.com
115. Following vaccination protective levels of
antibodies are believed to persist for seven
years
Need for booster dose is being debated
www.indiandentalacademy.com
116. Sterilization of OrthodonticSterilization of Orthodontic
PliersPliers
autoclave or chemiclave .
The only major obstacle of pliers
sterilization is related to their corrosion
suceptibility.
www.indiandentalacademy.com
117. corrosion resistance of orthodontic grade
steel is directly proportional to its chromium
content and inversely proportional to its carbon
content .
disruption of chromium oxide layer renders them
suceptible to corrosion.
Instruments made of carbon or 400 series steel are
more susceptible than those made of 300 series
steel.
www.indiandentalacademy.com
118. Steps to prevent corrosionSteps to prevent corrosion
first be cleaned thoroughly and rinsed with
distilled water .
do not allow contaminants to dry
Tap water to be avoided– use only distilled water
www.indiandentalacademy.com
119. Chrome-plated instruments should be autoclaved
separately from stainless steel ones.
Detergents with chloride bases should not be used
, Purple or black staining is caused by exposure to
ammonia.
*
www.indiandentalacademy.com
120. ArchwiresArchwires
Contaminated archwires are sterilized in
divided plastic containers
Cut to appropriate length and kept
overnight in gluteraldehyde solution
Thereafter stored in binsuntil ready to be
used
www.indiandentalacademy.com
121. Recycling of archwires
the relative high costs of archwires has lead to one
trying out the practice pf reclcycling of arch wires
Both cold and heat sterilization have been tried
Heating cycle should not exceed 235 C for a total
of 20 minsto keep impact on wires properties to
the minimum.
www.indiandentalacademy.com
122. Studies on Recycling ofStudies on Recycling of
Orthodontic Arch wiresOrthodontic Arch wires
www.indiandentalacademy.com
123. Mayshew ,Kusy Am.j.OrthoMayshew ,Kusy Am.j.Ortho
19881988
Effect of sterilization on mechanical properties
and surface topography of 0.017” x 0.025”
NiTinol and Titanal wires
Three methods:-
dry heat at 180 c for 60 min
formaldehyde alcohol vapour ,132c for 30 min
steam autoclave ,121 c for 20 min at 15-20 psi
www.indiandentalacademy.com
124. Tests conducted:-
Three point bending—elastic moduli
Surface topography –laser scattering
Tensile properties—instron utm
Results:-
No significant change in tensile properties with
any sterilization procedure
No change in elastic moduli
No apparent effect on surface topography
www.indiandentalacademy.com
125. Buckthal, Kusy :Am.J.Ortho .Buckthal, Kusy :Am.J.Ortho .
19981998
Effects of cold disinfectabnts on mechanical
properties and surface topography of 0.017” x
0.025” NiTinol and Titanal wires
Three disinfectants tested:-
2%acidic phetaraldehyde for 10 hours
Cholorine dioxide for 6 hours
Iodophor for 10 hours ..mixture at the ratio of
1/256 with water.
www.indiandentalacademy.com
126. Tests :-
Bending ,tensile,laser spectroscopy
Results :-
No change in elastic moduli
No change in surface topography
No change in tensile properties
www.indiandentalacademy.com
127. Laboratory AsepsisLaboratory Asepsis
Counter tops:-wipe counter tops with effective
disinfectants.
Impressions:-
easily contaminated with blood and saliva
microorganisms easily transferred from
contaminated impressions to casts where they can
remain viable for upto 7 days…thus providing a
path for cross contamination from the clinic to the
laboratory personnel
www.indiandentalacademy.com
128. Impressions after being removed from the mouth should
be rinsed under running water …this enables the removal
of adhering microorganisms
They are then placed into plastic bags with appropriate
disinfectants for approximately 15 mins…followed by
their removal and rinsing of the disinfectant…they are
now ready to be poured
If the impression is sensitive to immersion an alternate
would be to spray the impression with the appropriate
disinfectant and wrap it with a paper towel moistened with
the same disinfectant for 15 mins.
www.indiandentalacademy.com
129. BibliographyBibliography
White and Pharoah: Oral
Radiology:Principles and Interpretations
Robert langleins,Olaf
e.langland,McDavid:Panoramic Radiogaph
Casebow, M.P.:patient doses from
Orthopantomograph x-ray exposures,Br. J.
Radiol.,46:230,1973
www.indiandentalacademy.com
130. Chris H. Miller and Charles J.
Palenik:Infection Control and
management of Hazardous
Materials for the Dental Team
Mayshew,Kusy:Recycling of
orthodontic wires:Am. J. Ortho
1988
Buckthal,Kusy: Am. J. Ortho.1998
www.indiandentalacademy.com