INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com
www.indiandentalacademy.com
www.indiandentalacademy.com
ContentsContents
Introduction
Radiation biology
Radiation Chemistry
Effects of Radiation
Relevance of Radiation Expos...
Introduction
X-rays are a form of electromagnetic radiation
Ability to ionize matterwhich is the initiating
event in ra...
RADIATION BIOLOGYRADIATION BIOLOGY
 IS THE STUDY OF THE EFFECTS OF
IONIZING RADIATION ON THE LIVING
SYSTEM.

 Determini...
RADIATION CHEMISTRYRADIATION CHEMISTRY
 Free radical production
 RH + Photon R + H+
+ e
 These free radicals are unstab...
thus there is formation of structurally and
functionally biologic molecules differing from
original molecule.there by indu...
 Radiation acts on living system either
DIRECT INDIRECT
Direct ionization of biologic photon absorbed by
H2O
macromolecul...
Radiosensitvity and cell typeRadiosensitvity and cell type
 Most radiosensitive cells are are
1)undergoing mitoses
2)havi...
 Cells are usually divided into five categories of
radiosenstivity
1)vegetative inter mitotic cells
2)differentiating int...
)vegetative intermitotic cells—most radiosensitive
Eg:precursor cell–
spermatogenicerythoblastic ,basal cells of the oral
...
 Multi potential connective tissue cells –
---Eg intermediate radio sensitivity
--- : endothelial cells,fibroblasts
 Rev...
High Intermediate Low
Lymphoid Fine vasculature Optic lens
Bone marrow Growing cartilage Mature
Growing bone eryhtocytes
I...
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Radiation effects may be spoken In terms :-
the short term effects which bring about …
mitosis linked cell death
the lon...
Short term effectsShort term effects
 Primarily determined by the sensitivity of the
parenchymal cells of the respective
...
Long Term EffectsLong Term Effects
Determined by the extent of damage to the
fine vasculature of the tissue
Endothelial ...
 progressive fibrotic processes begins
around the capillaries
This fibrotic scar tissue will eventually
cause obliterati...
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Oral mucousOral mucous
membranemembrane
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• Oral mucous membrane
* Short term effects –related to the radiosensitive
vegetative intermitotic cells of the basal laye...
Taste budsTaste buds
*are radiosensitive—extensive degeneration
*loss of taste acuity during second or third
week of radio...
Salivary glandsSalivary glands
 The parenchymal component of salivary glands is
radiosensitive
 Short-term effects –infl...
Flora thus becomes more acidogenic in
saliva and plaque ---this along with thick
viscous ,acidic saliva---renders patient...
www.indiandentalacademy.com
Radiation cariesRadiation caries
Rampant form of decay
 Irradiation of the teeth does not influence the
decay but the ch...
Reducing ----daily application for 5 minutes
of a viscous topical 1% neutral NaF gel
--------avoidance of dietary sucrose...
TeethTeeth
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TeethTeeth
 Severity of damage is dose dependent
 If irradiation precedes calcification –tooth bud
destroyed
 After cal...
BoneBone
Primary damage—results from damage to
the vasculature of the periosteum and
cortical bone
Also the radiation te...
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OsteoradionecrosisOsteoradionecrosis
Decreased vascularity -renders bone
susceptible to infections
Source of these infe...
Relevance of Radiation
in Orthodontia
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Relevance of Radiation inRelevance of Radiation in
OrthodontiaOrthodontia
• Most commonly taken radiographs in
Orhtodontia...
 Exposure is of low doses …example for the
formation of cataract 2Sv(200 rem)but in opg
dose exposed to in the form of ...
Harmful effects manifest as increased
probability of a normally occurring disease
Bear in mind ALARA principle
www.india...
Maximum Permissible DoseMaximum Permissible Dose
 Two categories :-ouupationally exposed
 Non occupationally exposed
Who...
Radiation SafetyRadiation Safety
Two aspects:-
Patient Protection
Protection of Personnel
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Patient protection
1) Intensifying screens
2) Focal spot to film distance
3) Collimation
4) Filtration
5) Lead aprons and ...
Protection of PersonnelProtection of Personnel
Barrier/position and distance rule
Operator never hold film
Personnel sh...
 IS A COLLECTION OF SIGNS AND
SYMPTOMS EXPERIENCED BY PERSONS
AFTER ACUTE WHOLE BODY EXPOSURE
TO RADIATION
1)Prodromal Pe...
PRODROMAL PERIODPRODROMAL PERIOD
WITHIN FIRST MINUTES TO HOURSAFTER
EXPOSURE ,SYMPTOMS OF
GASTROINTESTINAL TRACT
DISTURBAN...
LATENT PERODLATENT PEROD
PERIOD OF APPARENT WELL BEING
EXTENT OF LATENT PERIOD IS DOSE
RELATED
www.indiandentalacademy.c...
HEMATOPOIETIC SYNDROMEHEMATOPOIETIC SYNDROME
 2 TO 7 Gy CAUSES INJURY TO THE
HEMATOPOETIC STEM CELLS OF THE
BONE MARROW ...
THE CLINICAL SIGNS OFTHE CLINICAL SIGNS OF
THE HEMATOPOIETICTHE HEMATOPOIETIC
SYNDROME INCLUDE-SYNDROME INCLUDE-
1)INFECTI...
GASTROINTESTINALGASTROINTESTINAL
SYNDROMESYNDROME
7 to 15 Gy causes extensive damage to the rapidly
proliferating epitheli...
These damages along with the hematopoietic
damage together contribute to the signs and
symptoms of GASTROINTESTINAL
SYNDR...
CARDIOVASCULAR AND CENTRALCARDIOVASCULAR AND CENTRAL
NERVOUS SYSTEM SYNDROMENERVOUS SYSTEM SYNDROME
Exposure to a dose in ...
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ContentsContents
 Introduction
 Mechanisms of Cross Infection
 Important Pathogens in Infection Control
 Control of Cr...
Pathways for Cross-Contamination
Patient to dental team
Dental team to patient
 Patient to patient
 Dental office t...
Mechanism or site of entry into
body:-
through breaks in
skinmucous membrane
through inhalation
www.indiandentalacademy...
www.indiandentalacademy.com
There are several important disease in
infection control but the ones of most
significance in the dental office are:-
Hep...
Infectious agent Disease or condition Route of
transmission
Incubation period Communicable
period
Hepatitis A virus ‘Infec...
Herpes Simplex
Virus
Type I ( HSV -1 )
Type II (HSV-2 )
Acute Herpetic
gingivostomatitis
Herpetic labialis
Ocular herpetic...
Treponema
pallidum
Syphilis Direct contact
Transplacental
10 days to 10 weeks Variable and
indefinite
Maybe 2 to 4 years
N...
Influenza
viruses
Influenza Nasal discharge
Respiratory
droplets
24 to 72 hrs 3 days from
clinical onset
Measles Virus
(Mo...
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 An infection-control program comprises two distinct
areas: exposure control and hazard
communication.
 Exposure control...
TerminologiesTerminologies
 Sterilization it is the process of destroying all
forms of microbial life
 Disinfection it...
Sanitizersreduce the microbial population to
safe levels as judged by public health
requirements.they are usually chemic...
SterilizationSterilization
Is a process intended to kill all
microorganisms whether vegetative or
pathogenic .
It is the...
The protocol for sterilization of instruments
is usually
1)holdingpresoaking
2)pre cleaning
3)sterilization process
4)as...
Holding PresoakingHolding Presoaking
If instrument not to be cleaned immediately
soak in holding solution prevents
sali...
Pre cleaningPre cleaning
Reduces amount of microbes present ,but
more importantly removes blood saliva and
other material...
Sterilization ProcessSterilization Process
A) Physical agents
B) Sunlight
C) Dry heat:-
flaming
incineration
hot air
D)...
F) Ultraviolet light
G)Radiation
H)Micro-wave
I)Lasers
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In dentistry the procedures used are:-
1)Heat sterilization
2)Gaseous sterilization
3) Liquid chemicals sterilization
www...
Heat sterilizationHeat sterilization
a) Moist heat:-steam pressure autoclave
b) Unsaturated chemical vapour:- chemiclave
c...
Steam Pressure AutoclaveSteam Pressure Autoclave
 Sterilizes by bringing about oxidation as well as
denaturing proteins
...
Advantages time efficient,good
penetration
Disadvantages 1)may lead to corrosion
of susceptible instruments.
2)items ...
Unsaturated Chemical vaporUnsaturated Chemical vapor
Chemical solution heated in a closed
solution-chemical vapor kills ...
Advantages
1)eliminates or reduces the corrosion of
susceptible instruments.
2)dry instruments available at end of cycle...
ChemiclavveChemiclavve
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Dry HeatDry Heat
 Conventional dry heat ovens
*heat chambers wherein heated air is circulated by
gravity convection
*320f...
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Short –cycle high temperature dry heat
ovens
Are force draft ovens
370°f to 375°f for 6 to 12 mins
Advantages :-1)instru...
Disadvantage
Instruments sensitive to elevated temp. will get
damaged
Ethylene oxide sterilization
 for complex, delicate...
Dry heat sterilizerDry heat sterilizer
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Boiling waterBoiling water
Even though seen to be used commonly it
does not kill spores and does not bring
about steriliz...
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Chemical MethodsChemical Methods
Chemical agents are used for controlling of
microbes on body surfaces and on
inanimate o...
Qualities of a universalQualities of a universal
disinfectantdisinfectant
1)destroy all forms of microorganisms
within a ...
ClassificationClassification
 Spaulding in 1972
A. High level disinfectants
Eg:-ethylene oxide gas,immersion
glutheralde...
C.Low level disinf.
Narrowest anti-microbial activity
Eg:- quaternary ammonium comps
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Categories of chemicalCategories of chemical
disinf.disinf.
 A) Alcohols
 B) Aldehydes
 C) Halogens
 D) Surfactants
 ...
A. Alcohols
bactericidal and fungicidal but not
sporicidal
MOA :- denature proteins
solvent action on lipids
Ethyl and ...
Alkalating agents
Formaldehyde
Gaseous state …used as a fumigant
MOA :- protoplasmic poison
denaturing proteins
 Disad...
Gluteraldehyde :-
less pungent volatile and irritating with
better disinfectant properties
broad spectrum of
activity2...
They also have a low surface tension
and can thus penetrate blood and
exudate thus reaching instruments
surfaces
Also us...
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HalogensHalogens
Iodine
Iodophors
Chlorine
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Chlorine
Sanitizing agent
Elemental chlorine used for water
purification
may also be used as a surface
disinfectant
...
Iodine :- used for wound and skin
antisepsis
Tinctures of iodine are usually used in
1,5and 7% conc. Which destroy 90%of...
SurfactantsSurfactants
Soaps :- degerm the skin by mecanical
removal of microbes
bacterostatic and bacteriocidial
www.ind...
Phenols :-
As disinfectants and antiseptics
MOA:-denaturing of proteins or damage to cell
membrane
Bacteroicidal and b...
www.indiandentalacademy.com
 These include :-
 Gloves
 Mouth masks
 Protective eyewear
 Hand washing
 Immunization
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GlovesGloves
The need for gloving
The practices of gloving not only
provides protection to dentist but also to
the patie...
For eg:-
Dentist
dentist contracts
treats herpes…herpes
whitlox
patient with herpes simplex
to patients treated in future...
Patient Care GlovesPatient Care Gloves
Disposable gloves
Do not wash gloves with detergents in an attempt
to reuse
Whil...
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Protective EyewearProtective Eyewear
 Protection from microbes
 Eg:HSV, Hepatitis B
 Protection against physical damage...
Preferable to use goggles over glasses as
former not only provides protection from
front splash and impacts but also from...
Hand washingHand washing
Two types of micro flora
 resident flora
transient flora
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Resident flora:colonize and become
resident
can never be completely
eliminated
less imp. In causing
disease
www.indian...
Transient flora:acquired whilst dealing
with contaminated objectssurfaces
do not colonize or
survive for long periods o...
Hand washing products containing low
levels of microbial agents used in a 10 –30
sec.hand wash routine minimizes the no.o...
Commonly used HandCommonly used Hand
DisinfectantsDisinfectants
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MasksMasks
Protect mucous membrane of mouth and
nose from contact with
aerosolssprayssplashes of oral fluids from
patient...
Dispose mask once it gets moist
resistance to airflow through the mask
increasesmore unfiltered air is allowed to
pass ...
ImmunizationImmunization
Hepatitis
The HBV is an infectious agent associated
with acute and chronic hepatitis .
Major cau...
Transmitted parenterally,sexual
contact,mother to fetus
HBV relatively environmentally stable…
potential for indirect t...
Following vaccination protective levels of
antibodies are believed to persist for seven
years
Need for booster dose is b...
Sterilization of OrthodonticSterilization of Orthodontic
PliersPliers
 autoclave or chemiclave .
The only major obstacle...
 corrosion resistance of orthodontic grade
steel is directly proportional to its chromium
content and inversely proportio...
Steps to prevent corrosionSteps to prevent corrosion
 first be cleaned thoroughly and rinsed with
distilled water .
 do ...
Chrome-plated instruments should be autoclaved
separately from stainless steel ones.
 Detergents with chloride bases sho...
ArchwiresArchwires
Contaminated archwires are sterilized in
divided plastic containers
Cut to appropriate length and kep...
Recycling of archwires
the relative high costs of archwires has lead to one
trying out the practice pf reclcycling of arc...
Studies on Recycling ofStudies on Recycling of
Orthodontic Arch wiresOrthodontic Arch wires
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Mayshew ,Kusy Am.j.OrthoMayshew ,Kusy Am.j.Ortho
19881988
 Effect of sterilization on mechanical properties
and surface t...
Tests conducted:-
Three point bending—elastic moduli
Surface topography –laser scattering
Tensile properties—instron u...
Buckthal, Kusy :Am.J.Ortho .Buckthal, Kusy :Am.J.Ortho .
19981998
 Effects of cold disinfectabnts on mechanical
propertie...
Tests :-
Bending ,tensile,laser spectroscopy
Results :-
No change in elastic moduli
No change in surface topography
...
Laboratory AsepsisLaboratory Asepsis
 Counter tops:-wipe counter tops with effective
disinfectants.
 Impressions:-
easi...
 Impressions after being removed from the mouth should
be rinsed under running water …this enables the removal
of adherin...
BibliographyBibliography
White and Pharoah: Oral
Radiology:Principles and Interpretations
Robert langleins,Olaf
e.langla...
Chris H. Miller and Charles J.
Palenik:Infection Control and
management of Hazardous
Materials for the Dental Team
Maysh...
www.indiandentalacademy.com
For more details please visit
www.indiandentalacademy.com
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Acute radiation syndrome 34 /certified fixed orthodontic courses by Indian dental academy

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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.

Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078

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Acute radiation syndrome 34 /certified fixed orthodontic courses by Indian dental academy

  1. 1. INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  2. 2. www.indiandentalacademy.com
  3. 3. ContentsContents Introduction Radiation biology Radiation Chemistry Effects of Radiation Relevance of Radiation Exposure in orthodontics Radiation Protection Bibliography www.indiandentalacademy.com
  4. 4. Introduction X-rays are a form of electromagnetic radiation Ability to ionize matterwhich is the initiating event in radiation induced biologic changes www.indiandentalacademy.com
  5. 5. 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
  6. 6. 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
  7. 7. thus there is formation of structurally and functionally biologic molecules differing from original molecule.there by inducing biological change. www.indiandentalacademy.com
  8. 8.  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
  9. 9. 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
  10. 10.  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
  11. 11. )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
  12. 12.  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
  13. 13. 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. 14. www.indiandentalacademy.com
  15. 15. 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
  16. 16. Short term effectsShort term effects  Primarily determined by the sensitivity of the parenchymal cells of the respective tissue  Raidly proliferatingcell 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
  17. 17. 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
  18. 18.  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
  19. 19. www.indiandentalacademy.com
  20. 20. Oral mucousOral mucous membranemembrane www.indiandentalacademy.com
  21. 21. • 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
  22. 22. 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
  23. 23. 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
  24. 24. 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. 25. www.indiandentalacademy.com
  26. 26. 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
  27. 27. Reducing ----daily application for 5 minutes of a viscous topical 1% neutral NaF gel --------avoidance of dietary sucrose www.indiandentalacademy.com
  28. 28. TeethTeeth www.indiandentalacademy.com
  29. 29. 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
  30. 30. 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. 31. www.indiandentalacademy.com
  32. 32. 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. 33. Relevance of Radiation in Orthodontia www.indiandentalacademy.com
  34. 34. 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
  35. 35.  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  Thyroid160-370 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
  36. 36. Harmful effects manifest as increased probability of a normally occurring disease Bear in mind ALARA principle www.indiandentalacademy.com
  37. 37. 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. 38. Radiation SafetyRadiation Safety Two aspects:- Patient Protection Protection of Personnel www.indiandentalacademy.com
  39. 39. 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
  40. 40. 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
  41. 41.  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
  42. 42. 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. 43. LATENT PERODLATENT PEROD PERIOD OF APPARENT WELL BEING EXTENT OF LATENT PERIOD IS DOSE RELATED www.indiandentalacademy.com
  44. 44. 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
  45. 45. 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
  46. 46. 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
  47. 47. These damages along with the hematopoietic damage together contribute to the signs and symptoms of GASTROINTESTINAL SYNDROME www.indiandentalacademy.com
  48. 48. 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
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  50. 50. ContentsContents  Introduction  Mechanisms of Cross Infection  Important Pathogens in Infection Control  Control of Cross-Infection  Sterilization in Orthodontics www.indiandentalacademy.com
  51. 51. 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
  52. 52. Mechanism or site of entry into body:- through breaks in skinmucous membrane through inhalation www.indiandentalacademy.com
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  54. 54. 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
  55. 55. 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
  56. 56. 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
  57. 57. 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
  58. 58. 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
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  60. 60.  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
  61. 61. 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-septicsthese are substances that prevent the growth or action of microbes by either destroying them or inhibiting their actions www.indiandentalacademy.com
  62. 62. Sanitizersreduce 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. Germicideskill 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
  63. 63. 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
  64. 64. 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
  65. 65. 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 soakingcorrosion www.indiandentalacademy.com
  66. 66. 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
  67. 67. 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. 68. F) Ultraviolet light G)Radiation H)Micro-wave I)Lasers www.indiandentalacademy.com
  69. 69. In dentistry the procedures used are:- 1)Heat sterilization 2)Gaseous sterilization 3) Liquid chemicals sterilization www.indiandentalacademy.com
  70. 70. 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
  71. 71. 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 cyclesStandard..20 –30 mins.at 250°f Flash cycles..3-10 mins.at 273°f www.indiandentalacademy.com
  72. 72. Advantages time efficient,good penetration Disadvantages 1)may lead to corrosion of susceptible instruments. 2)items sensitive to elevated temperatures get damaged www.indiandentalacademy.com
  73. 73. 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
  74. 74. 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. 75. ChemiclavveChemiclavve www.indiandentalacademy.com
  76. 76. 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
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  78. 78. 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
  79. 79. 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. 80. Dry heat sterilizerDry heat sterilizer www.indiandentalacademy.com
  81. 81. 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
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  83. 83. www.indiandentalacademy.com
  84. 84. Chemical MethodsChemical Methods Chemical agents are used for controlling of microbes on body surfaces and on inanimate objects are grouped under disinfectants These includeantiseptics sanitizing degerming disinfecting agents www.indiandentalacademy.com
  85. 85. 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 penetrabilityfor effective contact even in the presence of blood and exudate 5)readily soluble in available solvents www.indiandentalacademy.com
  86. 86. 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. 87. C.Low level disinf. Narrowest anti-microbial activity Eg:- quaternary ammonium comps www.indiandentalacademy.com
  88. 88. 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
  89. 89. 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
  90. 90. 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
  91. 91. Gluteraldehyde :- less pungent volatile and irritating with better disinfectant properties broad spectrum of activity2%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
  92. 92. 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
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  94. 94. HalogensHalogens Iodine Iodophors Chlorine www.indiandentalacademy.com
  95. 95. 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
  96. 96. 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. 97. SurfactantsSurfactants Soaps :- degerm the skin by mecanical removal of microbes bacterostatic and bacteriocidial www.indiandentalacademy.com
  98. 98. Phenols :- As disinfectants and antiseptics MOA:-denaturing of proteins or damage to cell membrane Bacteroicidal and bacteriostatic…but poor viricidal properties www.indiandentalacademy.com
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  100. 100.  These include :-  Gloves  Mouth masks  Protective eyewear  Hand washing  Immunization www.indiandentalacademy.com
  101. 101. GlovesGloves The need for gloving The practices of gloving not only provides protection to dentist but also to the patient www.indiandentalacademy.com
  102. 102. For eg:- Dentist dentist contracts treats herpes…herpes whitlox patient with herpes simplex to patients treated in future www.indiandentalacademy.com
  103. 103. 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
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  105. 105. 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
  106. 106. 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
  107. 107. Hand washingHand washing Two types of micro flora  resident flora transient flora www.indiandentalacademy.com
  108. 108. Resident flora:colonize and become resident can never be completely eliminated less imp. In causing disease www.indiandentalacademy.com
  109. 109. 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
  110. 110. 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. 111. Commonly used HandCommonly used Hand DisinfectantsDisinfectants www.indiandentalacademy.com
  112. 112. 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
  113. 113. Dispose mask once it gets moist resistance to airflow through the mask increasesmore unfiltered air is allowed to pass by the edge of the mask Use disposable maskschanging between patients www.indiandentalacademy.com
  114. 114. 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
  115. 115. 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
  116. 116. Following vaccination protective levels of antibodies are believed to persist for seven years Need for booster dose is being debated www.indiandentalacademy.com
  117. 117. 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
  118. 118.  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
  119. 119. 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
  120. 120. 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
  121. 121. ArchwiresArchwires Contaminated archwires are sterilized in divided plastic containers Cut to appropriate length and kept overnight in gluteraldehyde solution Thereafter stored in binsuntil ready to be used www.indiandentalacademy.com
  122. 122. 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 minsto keep impact on wires properties to the minimum. www.indiandentalacademy.com
  123. 123. Studies on Recycling ofStudies on Recycling of Orthodontic Arch wiresOrthodontic Arch wires www.indiandentalacademy.com
  124. 124. 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
  125. 125. 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
  126. 126. 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
  127. 127. Tests :- Bending ,tensile,laser spectroscopy Results :- No change in elastic moduli No change in surface topography No change in tensile properties www.indiandentalacademy.com
  128. 128. 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
  129. 129.  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
  130. 130. 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
  131. 131. 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
  132. 132. www.indiandentalacademy.com For more details please visit www.indiandentalacademy.com

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