SlideShare una empresa de Scribd logo
1 de 19
Descargar para leer sin conexión
Manipulation of amalgam
Manipulation of amalgam
Manipulation of dental amalgam
 1) Selection of alloys
 2) Proportioning and dispencing
 3) Trituration
 4)Condensation
 5)Carving
 6)Finishing and polishing
Selection of alloys:
 For restorations subjected to occlusal forces, an
amalgam with high resistance to marginal fracture is
desirable.
 If strength is needed quickly the best chice is spherical
or high copper alloys, but they require a fast operator.
 It is estimated that the majority of the dental
amalgams currently placed are high copper alloys,
spherical – unicompositional or admixed types.
Proportioning and Dispensing:
 Proportioned capsules containing alloy particles and
mercury in compartments separated by a disk or
membrane are available.
Manipulation of amalgam
Trituration:
 Trituration is the process by which mercury is allowed
to react with the alloy powder. This procedure allows
the rubbing of the surface oxide on amalgam particles,
exposing an active surface to react with mercury.
 Trituration: 1) hand trituration
2) mechanical trituration
Hand Mixing:
> A glass mortar
and pestle is used.
The mortar has its
inner surface
roughened to
increase the friction
between amalgam
and glass surface
with carborundum
paste. A pestle is a
glass road with a
round end.
Mechanical Mixing:
 The disposable capsule serves as a mortar. Some
capsules have a cylindrical metal or plastic piece in the
capsule which serves as the pestle.
 Reusable capsules are available with friction fit or
screw – type lids.
 Amalgamators have automatic timer and speed control
device. The speed ranges from 3200 to 4400 cycles per
minute. High copper alloys require higher mixing
speed.
Mechanical amalgamator for proportioned capsules (left)
Close-up the mechanical arm that grips and vibrates the capsules.
Effect of over trituration and under
trituration:
 Working time decrease with over trituration.
 Setting contraction increases with over-trituration.
 Compressive and tensile strengths increase with over-
trituration of lath cut alloys; however they decrease
with over- and under-trituration of spherical alloys.
 Creep increases with over-trituration.
Condensation:
 The amalgam is placed in the cavity after trituration,
and condensed using suitable instrument.
 Proper condensation increase the strength and
decrease the creep of the amalgam. Condensation
must always be done within the four walls and floor.
 If one or more walls of the cavity are missing, a steel
matrix may be used to compensate for it.
Manual Condensation:
 The mixed material is condensed in increments. Each
increment is carried to the prepared cavity by means
of a small forceps or an amalgam carrier.
 Once inserted, it should be condensed immediately
with sufficient pressure (approximately 3 to 4 pounds).
Mechanical Condensation:
 Mechanical condensers provide vibration or impact
type of force to pack the amalgam mix. Less effort is
needed than for hand condensation.
Carving
 The amalgam is overfilled into the cavity and the
mercury rich surface layer is trimmed away.
 The filling is carved to reproduce the tooth anatomy.
The carving should not be started until the amalgam is
hard enough to offer resistance to the carving
instrument.
 A scraping or ringing sound should be heard when it is
carved.
 If the carving is started too soon, the amalgam may be
so plastic that it may pull away from the margins.
Burnishing:
 After the carving, the restoration is smoothened, by
burnishing the surfaceand margins of the restoration.
 Burnishing slow setting alloys can damage the margins
of the restoration.
 Burnishing is done with ball burnisher using light
stroke proceeding from the amalgam surface to the
tooth surface. Final smoothing can be done by rubbing
the surface with a moist cotton pellet.
Polishing
 Polishing minimizes
corroision and prevents
adherence of plaque. The
polishing should be
delayed for atleast 24
hours after
condensation.
Thank You

Más contenido relacionado

La actualidad más candente

Principles of teeth arrangement and compensatory curves
Principles of teeth arrangement and compensatory curves Principles of teeth arrangement and compensatory curves
Principles of teeth arrangement and compensatory curves Huma Javeria
 
steps of cavity preparation for class 1
steps of cavity preparation for class 1 steps of cavity preparation for class 1
steps of cavity preparation for class 1 Parikshit Harnoor
 
Gass Ionomer Cement
Gass Ionomer CementGass Ionomer Cement
Gass Ionomer Cementshabeel pn
 
Tarnish & corrosion in dentistry
Tarnish & corrosion in dentistryTarnish & corrosion in dentistry
Tarnish & corrosion in dentistryDr Mujtaba Ashraf
 
Fundamentals in tooth preparation .
Fundamentals in tooth preparation .Fundamentals in tooth preparation .
Fundamentals in tooth preparation .Priyesh Kharat
 
Alginate Dental Material
Alginate Dental MaterialAlginate Dental Material
Alginate Dental MaterialDr. Ishu SINGLA
 
Alginate-Irreversible Hydrocolloid
Alginate-Irreversible HydrocolloidAlginate-Irreversible Hydrocolloid
Alginate-Irreversible HydrocolloidAmeet Agrawal
 
Special tray prosthodontics
Special tray prosthodonticsSpecial tray prosthodontics
Special tray prosthodonticsShazlana Raheem
 
Hand instruments in operative dentistry
Hand instruments in operative dentistryHand instruments in operative dentistry
Hand instruments in operative dentistryAbhijeet Khade
 
Fundamentals in tooth preparation (conservative dentistry)
Fundamentals in tooth preparation (conservative dentistry)Fundamentals in tooth preparation (conservative dentistry)
Fundamentals in tooth preparation (conservative dentistry)Adwiti Vidushi
 

La actualidad más candente (20)

Dental ceramics
Dental ceramicsDental ceramics
Dental ceramics
 
Denture Base Resin
Denture Base Resin Denture Base Resin
Denture Base Resin
 
Principles of teeth arrangement and compensatory curves
Principles of teeth arrangement and compensatory curves Principles of teeth arrangement and compensatory curves
Principles of teeth arrangement and compensatory curves
 
steps of cavity preparation for class 1
steps of cavity preparation for class 1 steps of cavity preparation for class 1
steps of cavity preparation for class 1
 
Gass Ionomer Cement
Gass Ionomer CementGass Ionomer Cement
Gass Ionomer Cement
 
Zinc Phosphate Cement
Zinc Phosphate CementZinc Phosphate Cement
Zinc Phosphate Cement
 
Tarnish & corrosion in dentistry
Tarnish & corrosion in dentistryTarnish & corrosion in dentistry
Tarnish & corrosion in dentistry
 
Impression compound
Impression compoundImpression compound
Impression compound
 
Fundamentals in tooth preparation .
Fundamentals in tooth preparation .Fundamentals in tooth preparation .
Fundamentals in tooth preparation .
 
Dental ceramics
Dental ceramicsDental ceramics
Dental ceramics
 
Dental burs
Dental bursDental burs
Dental burs
 
Alginate Dental Material
Alginate Dental MaterialAlginate Dental Material
Alginate Dental Material
 
Dental waxes final ppt
Dental waxes final pptDental waxes final ppt
Dental waxes final ppt
 
Class II cavity preparation
Class II cavity preparationClass II cavity preparation
Class II cavity preparation
 
Direct filling gold
Direct filling goldDirect filling gold
Direct filling gold
 
Alginate-Irreversible Hydrocolloid
Alginate-Irreversible HydrocolloidAlginate-Irreversible Hydrocolloid
Alginate-Irreversible Hydrocolloid
 
Special tray prosthodontics
Special tray prosthodonticsSpecial tray prosthodontics
Special tray prosthodontics
 
Amalgam
AmalgamAmalgam
Amalgam
 
Hand instruments in operative dentistry
Hand instruments in operative dentistryHand instruments in operative dentistry
Hand instruments in operative dentistry
 
Fundamentals in tooth preparation (conservative dentistry)
Fundamentals in tooth preparation (conservative dentistry)Fundamentals in tooth preparation (conservative dentistry)
Fundamentals in tooth preparation (conservative dentistry)
 

Similar a Manipulation of amalgam

Similar a Manipulation of amalgam (20)

MANIPULATION OF AMALGAM.pptx
MANIPULATION OF AMALGAM.pptxMANIPULATION OF AMALGAM.pptx
MANIPULATION OF AMALGAM.pptx
 
Mana
Mana Mana
Mana
 
Trituration
TriturationTrituration
Trituration
 
procedure for amalgam restoration
procedure for amalgam restorationprocedure for amalgam restoration
procedure for amalgam restoration
 
Amalgam seminar part 2
Amalgam seminar part 2Amalgam seminar part 2
Amalgam seminar part 2
 
Dental amalgam
Dental amalgamDental amalgam
Dental amalgam
 
Dental amalgam power point by Dr.Kazhan O. Abdulrahman
Dental amalgam power point by Dr.Kazhan O. AbdulrahmanDental amalgam power point by Dr.Kazhan O. Abdulrahman
Dental amalgam power point by Dr.Kazhan O. Abdulrahman
 
Abrasion and polishing agents (2)
Abrasion and polishing agents (2)Abrasion and polishing agents (2)
Abrasion and polishing agents (2)
 
Oper.ii 13
Oper.ii 13Oper.ii 13
Oper.ii 13
 
Amalgam newest.pptx
Amalgam newest.pptxAmalgam newest.pptx
Amalgam newest.pptx
 
Abrasion and polishing
Abrasion and polishingAbrasion and polishing
Abrasion and polishing
 
Oper.ii 06
Oper.ii 06Oper.ii 06
Oper.ii 06
 
Ultrasonic machining (modern manufacturing process)
Ultrasonic machining (modern manufacturing process)Ultrasonic machining (modern manufacturing process)
Ultrasonic machining (modern manufacturing process)
 
ABRASION AND POLISHING_013313.pptx
ABRASION AND POLISHING_013313.pptxABRASION AND POLISHING_013313.pptx
ABRASION AND POLISHING_013313.pptx
 
Oper.ii 04
Oper.ii 04Oper.ii 04
Oper.ii 04
 
Casting & defects
Casting & defectsCasting & defects
Casting & defects
 
mm_pract5.ppt
mm_pract5.pptmm_pract5.ppt
mm_pract5.ppt
 
Size reduction (GIKI)
Size reduction (GIKI)Size reduction (GIKI)
Size reduction (GIKI)
 
Abrasion and polishing agents
Abrasion and polishing agentsAbrasion and polishing agents
Abrasion and polishing agents
 
dentalamalgam.pptx
dentalamalgam.pptxdentalamalgam.pptx
dentalamalgam.pptx
 

Más de Rohan Vadsola

Finishing and polishing of restoration
Finishing and polishing of restorationFinishing and polishing of restoration
Finishing and polishing of restorationRohan Vadsola
 
Non carious cervical lesion
Non carious  cervical lesionNon carious  cervical lesion
Non carious cervical lesionRohan Vadsola
 
Classification of malocclusion
Classification of malocclusionClassification of malocclusion
Classification of malocclusionRohan Vadsola
 
Flouride in dentistry
Flouride in dentistryFlouride in dentistry
Flouride in dentistryRohan Vadsola
 
Chair and operator position
Chair and operator positionChair and operator position
Chair and operator positionRohan Vadsola
 
Etiology of malocclusion
Etiology of malocclusionEtiology of malocclusion
Etiology of malocclusionRohan Vadsola
 
Periradicular diseas
Periradicular diseasPeriradicular diseas
Periradicular diseasRohan Vadsola
 
Arrangement of teeth in class 2 relation
Arrangement of teeth in class 2 relationArrangement of teeth in class 2 relation
Arrangement of teeth in class 2 relationRohan Vadsola
 
Think in enlightened self interest
Think in enlightened self interestThink in enlightened self interest
Think in enlightened self interestRohan Vadsola
 
Mechanics of tooth_movement-_ortho
Mechanics of tooth_movement-_orthoMechanics of tooth_movement-_ortho
Mechanics of tooth_movement-_orthoRohan Vadsola
 
CAVITY NOMENCLATURE & IT'S TERMINOLOGY
CAVITY NOMENCLATURE & IT'S TERMINOLOGYCAVITY NOMENCLATURE & IT'S TERMINOLOGY
CAVITY NOMENCLATURE & IT'S TERMINOLOGYRohan Vadsola
 
Artificial Intelligence
Artificial IntelligenceArtificial Intelligence
Artificial IntelligenceRohan Vadsola
 

Más de Rohan Vadsola (16)

Finishing and polishing of restoration
Finishing and polishing of restorationFinishing and polishing of restoration
Finishing and polishing of restoration
 
Non carious cervical lesion
Non carious  cervical lesionNon carious  cervical lesion
Non carious cervical lesion
 
Tharmal emergencies
Tharmal  emergenciesTharmal  emergencies
Tharmal emergencies
 
Classification of malocclusion
Classification of malocclusionClassification of malocclusion
Classification of malocclusion
 
Flouride in dentistry
Flouride in dentistryFlouride in dentistry
Flouride in dentistry
 
Chair and operator position
Chair and operator positionChair and operator position
Chair and operator position
 
Etiology of malocclusion
Etiology of malocclusionEtiology of malocclusion
Etiology of malocclusion
 
Periradicular diseas
Periradicular diseasPeriradicular diseas
Periradicular diseas
 
Arrangement of teeth in class 2 relation
Arrangement of teeth in class 2 relationArrangement of teeth in class 2 relation
Arrangement of teeth in class 2 relation
 
Think in enlightened self interest
Think in enlightened self interestThink in enlightened self interest
Think in enlightened self interest
 
Google
GoogleGoogle
Google
 
Mechanics of tooth_movement-_ortho
Mechanics of tooth_movement-_orthoMechanics of tooth_movement-_ortho
Mechanics of tooth_movement-_ortho
 
CAVITY NOMENCLATURE & IT'S TERMINOLOGY
CAVITY NOMENCLATURE & IT'S TERMINOLOGYCAVITY NOMENCLATURE & IT'S TERMINOLOGY
CAVITY NOMENCLATURE & IT'S TERMINOLOGY
 
Artificial Intelligence
Artificial IntelligenceArtificial Intelligence
Artificial Intelligence
 
Smart watch
Smart watchSmart watch
Smart watch
 
Android Technology
Android TechnologyAndroid Technology
Android Technology
 

Último

ARTICULAR DISC OF TEMPOROMANDIBULAR JOINT
ARTICULAR DISC OF TEMPOROMANDIBULAR JOINTARTICULAR DISC OF TEMPOROMANDIBULAR JOINT
ARTICULAR DISC OF TEMPOROMANDIBULAR JOINTDR. SNEHA NAIR
 
Prescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxPrescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxraviapr7
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapitolTechU
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsEugene Lysak
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?TechSoup
 
AUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptxAUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptxiammrhaywood
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxDr. Asif Anas
 
KARNAADA.pptx made by - saransh dwivedi ( SD ) - SHALAKYA TANTRA - ENT - 4...
KARNAADA.pptx  made by -  saransh dwivedi ( SD ) -  SHALAKYA TANTRA - ENT - 4...KARNAADA.pptx  made by -  saransh dwivedi ( SD ) -  SHALAKYA TANTRA - ENT - 4...
KARNAADA.pptx made by - saransh dwivedi ( SD ) - SHALAKYA TANTRA - ENT - 4...M56BOOKSTORE PRODUCT/SERVICE
 
SOLIDE WASTE in Cameroon,,,,,,,,,,,,,,,,,,,,,,,,,,,.pptx
SOLIDE WASTE in Cameroon,,,,,,,,,,,,,,,,,,,,,,,,,,,.pptxSOLIDE WASTE in Cameroon,,,,,,,,,,,,,,,,,,,,,,,,,,,.pptx
SOLIDE WASTE in Cameroon,,,,,,,,,,,,,,,,,,,,,,,,,,,.pptxSyedNadeemGillANi
 
A gentle introduction to Artificial Intelligence
A gentle introduction to Artificial IntelligenceA gentle introduction to Artificial Intelligence
A gentle introduction to Artificial IntelligenceApostolos Syropoulos
 
3.21.24 The Origins of Black Power.pptx
3.21.24  The Origins of Black Power.pptx3.21.24  The Origins of Black Power.pptx
3.21.24 The Origins of Black Power.pptxmary850239
 
Diploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdfDiploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdfMohonDas
 
Work Experience for psp3 portfolio sasha
Work Experience for psp3 portfolio sashaWork Experience for psp3 portfolio sasha
Work Experience for psp3 portfolio sashasashalaycock03
 
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...Dr. Asif Anas
 
How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17Celine George
 
Quality Assurance_GOOD LABORATORY PRACTICE
Quality Assurance_GOOD LABORATORY PRACTICEQuality Assurance_GOOD LABORATORY PRACTICE
Quality Assurance_GOOD LABORATORY PRACTICESayali Powar
 
In - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptxIn - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptxAditiChauhan701637
 
How to Solve Singleton Error in the Odoo 17
How to Solve Singleton Error in the  Odoo 17How to Solve Singleton Error in the  Odoo 17
How to Solve Singleton Error in the Odoo 17Celine George
 
Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.raviapr7
 

Último (20)

ARTICULAR DISC OF TEMPOROMANDIBULAR JOINT
ARTICULAR DISC OF TEMPOROMANDIBULAR JOINTARTICULAR DISC OF TEMPOROMANDIBULAR JOINT
ARTICULAR DISC OF TEMPOROMANDIBULAR JOINT
 
Prescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxPrescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptx
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptx
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George Wells
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?
 
AUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptxAUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptx
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptx
 
KARNAADA.pptx made by - saransh dwivedi ( SD ) - SHALAKYA TANTRA - ENT - 4...
KARNAADA.pptx  made by -  saransh dwivedi ( SD ) -  SHALAKYA TANTRA - ENT - 4...KARNAADA.pptx  made by -  saransh dwivedi ( SD ) -  SHALAKYA TANTRA - ENT - 4...
KARNAADA.pptx made by - saransh dwivedi ( SD ) - SHALAKYA TANTRA - ENT - 4...
 
SOLIDE WASTE in Cameroon,,,,,,,,,,,,,,,,,,,,,,,,,,,.pptx
SOLIDE WASTE in Cameroon,,,,,,,,,,,,,,,,,,,,,,,,,,,.pptxSOLIDE WASTE in Cameroon,,,,,,,,,,,,,,,,,,,,,,,,,,,.pptx
SOLIDE WASTE in Cameroon,,,,,,,,,,,,,,,,,,,,,,,,,,,.pptx
 
A gentle introduction to Artificial Intelligence
A gentle introduction to Artificial IntelligenceA gentle introduction to Artificial Intelligence
A gentle introduction to Artificial Intelligence
 
3.21.24 The Origins of Black Power.pptx
3.21.24  The Origins of Black Power.pptx3.21.24  The Origins of Black Power.pptx
3.21.24 The Origins of Black Power.pptx
 
Prelims of Kant get Marx 2.0: a general politics quiz
Prelims of Kant get Marx 2.0: a general politics quizPrelims of Kant get Marx 2.0: a general politics quiz
Prelims of Kant get Marx 2.0: a general politics quiz
 
Diploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdfDiploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdf
 
Work Experience for psp3 portfolio sasha
Work Experience for psp3 portfolio sashaWork Experience for psp3 portfolio sasha
Work Experience for psp3 portfolio sasha
 
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
 
How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17
 
Quality Assurance_GOOD LABORATORY PRACTICE
Quality Assurance_GOOD LABORATORY PRACTICEQuality Assurance_GOOD LABORATORY PRACTICE
Quality Assurance_GOOD LABORATORY PRACTICE
 
In - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptxIn - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptx
 
How to Solve Singleton Error in the Odoo 17
How to Solve Singleton Error in the  Odoo 17How to Solve Singleton Error in the  Odoo 17
How to Solve Singleton Error in the Odoo 17
 
Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.
 

Manipulation of amalgam

  • 3. Manipulation of dental amalgam  1) Selection of alloys  2) Proportioning and dispencing  3) Trituration  4)Condensation  5)Carving  6)Finishing and polishing
  • 4. Selection of alloys:  For restorations subjected to occlusal forces, an amalgam with high resistance to marginal fracture is desirable.  If strength is needed quickly the best chice is spherical or high copper alloys, but they require a fast operator.  It is estimated that the majority of the dental amalgams currently placed are high copper alloys, spherical – unicompositional or admixed types.
  • 5. Proportioning and Dispensing:  Proportioned capsules containing alloy particles and mercury in compartments separated by a disk or membrane are available.
  • 7. Trituration:  Trituration is the process by which mercury is allowed to react with the alloy powder. This procedure allows the rubbing of the surface oxide on amalgam particles, exposing an active surface to react with mercury.  Trituration: 1) hand trituration 2) mechanical trituration
  • 8. Hand Mixing: > A glass mortar and pestle is used. The mortar has its inner surface roughened to increase the friction between amalgam and glass surface with carborundum paste. A pestle is a glass road with a round end.
  • 9. Mechanical Mixing:  The disposable capsule serves as a mortar. Some capsules have a cylindrical metal or plastic piece in the capsule which serves as the pestle.  Reusable capsules are available with friction fit or screw – type lids.  Amalgamators have automatic timer and speed control device. The speed ranges from 3200 to 4400 cycles per minute. High copper alloys require higher mixing speed.
  • 10. Mechanical amalgamator for proportioned capsules (left) Close-up the mechanical arm that grips and vibrates the capsules.
  • 11. Effect of over trituration and under trituration:  Working time decrease with over trituration.  Setting contraction increases with over-trituration.  Compressive and tensile strengths increase with over- trituration of lath cut alloys; however they decrease with over- and under-trituration of spherical alloys.  Creep increases with over-trituration.
  • 12. Condensation:  The amalgam is placed in the cavity after trituration, and condensed using suitable instrument.  Proper condensation increase the strength and decrease the creep of the amalgam. Condensation must always be done within the four walls and floor.  If one or more walls of the cavity are missing, a steel matrix may be used to compensate for it.
  • 13. Manual Condensation:  The mixed material is condensed in increments. Each increment is carried to the prepared cavity by means of a small forceps or an amalgam carrier.  Once inserted, it should be condensed immediately with sufficient pressure (approximately 3 to 4 pounds).
  • 14. Mechanical Condensation:  Mechanical condensers provide vibration or impact type of force to pack the amalgam mix. Less effort is needed than for hand condensation.
  • 15. Carving  The amalgam is overfilled into the cavity and the mercury rich surface layer is trimmed away.  The filling is carved to reproduce the tooth anatomy. The carving should not be started until the amalgam is hard enough to offer resistance to the carving instrument.
  • 16.  A scraping or ringing sound should be heard when it is carved.  If the carving is started too soon, the amalgam may be so plastic that it may pull away from the margins.
  • 17. Burnishing:  After the carving, the restoration is smoothened, by burnishing the surfaceand margins of the restoration.  Burnishing slow setting alloys can damage the margins of the restoration.  Burnishing is done with ball burnisher using light stroke proceeding from the amalgam surface to the tooth surface. Final smoothing can be done by rubbing the surface with a moist cotton pellet.
  • 18. Polishing  Polishing minimizes corroision and prevents adherence of plaque. The polishing should be delayed for atleast 24 hours after condensation.