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Operative dentistry
Lec1
‫د‬
/
‫عدنان‬
‫عمران‬
Introduction
Operative dentistry
is defined as science and art of dentistry which deals with diagnosis, treatment and
prognosis of defects of the teeth which do not require full coverage restorations for
correction”.
Such corrections and restorations result in the restoration of proper tooth form, function
and aesthetics while maintaining the physiological integrity of the teeth in harmonious
relationship with the adjacent hard and soft tissues.
Introduction
Indications of operative dentistry procedures
❖ Caries
Dental caries is an infectious microbiological disease of the teeth which results in localized dissolution and destruction of
the calcified tissue
❖ Noncarious Loss of the Tooth Structure due to Attrition, Abrasion, Abfraction and Erosion
Attrition
Mechanical wear between opposing teeth commonly due to excessive masticatory forces.
Abrasion
Loss of tooth material by mechanical means other than by opposing teeth.
Erosion
Loss of dental hard tissue as a result of a chemical process not involving bacteria.
Indications of operative dentistry procedures
❖ Malformed, Traumatized, or Fractured Teeth
Traumatic injuries may involve the hard dental tissues and the pulp which require restoration.
❖ Esthetic Improvement
Discolored teeth because of staining or other reasons look unesthetic and require restoration.
❖ Replacement or Repair of Restoration
Repair or replacement of previous defective restoration is indicated for operative treatment.
Scope of Operative Dentistry
Scope of operative dentistry includes the following:
• To know the condition of the affected tooth and other teeth.
• To examine not only the affected tooth but also the oral and systemic health of the patient.
• To diagnose the dental problem and the interaction of problem area with other tissues.
• Provide optimal treatment plan to restore the tooth to return to health and function.
• Thorough knowledge of dental materials which can be used to restore the affected areas.
• To maintain the pulp vitality and prevent occurrence of pulpal pathology.
• To have knowledge of dental anatomy and histology.
.
Purpose of operative dentistry
Diagnosis
Proper diagnosis is vital for treatment planning
Prevention
To prevent any recurrence of the causative disease and their defects
Interception
Preventing further loss of tooth structure by stabilizing an active disease process..
Preservation
Preservation of the vitality and periodontal support of remaining tooth structure.
Restoration
Includes restoring form, function, phonetics and aesthetics.
Maintenance
After restoration is done, it must be maintained for providing service for longer duration.
Purpose of operative dentistry
TERMINOLOGY OF TOOTH PREPARATION
It is the mechanical alteration of a defective, injured or diseased tooth in order
to best receive a restorative
Simple Tooth Preparation
A tooth preparation involving only one tooth surface is termed simple preparation for
example occlusal preparation.
Compound Tooth Preparation
A tooth preparation involving two surfaces is termed compound tooth preparation for
example mesioocclusal or disto-occlusal preparation.
Complex Tooth Preparation
A tooth preparation involving more than two surfaces is called as complex tooth
preparation for example MOD preparation.
Tooth Preparation Walls
Internal Wall
It is a wall in the preparation, which is not extended to the external tooth surface
External Wall:-
An external wall is a wall in the prepared tooth that extends to the external tooth surface.
External wall takes the name of the tooth surface towards which it is situated.
Tooth Preparation Walls
Tooth Preparation Walls
Pulpal Wall:-
A pulpal wall is an internal wall that is towards the pulp and covering the pulp. It may be
both vertical and perpendicular to the long axis of tooth.
Tooth Preparation Walls
Axial Wall:-
It is an internal wall which is parallel to the long axis of the tooth .
Floor:-
Floor is a prepared wall which is usually flat and perpendicular to the occlusal forces
directed occlusogingivally,for example, pulpal and gingival walls .
Tooth Preparation Walls
Cavosurface Angle Margin/Tooth Preparation Margin
Cavosurface angle is formed by the junction of a prepared tooth surface wall and
external surface of the tooth .The acute junction is referred to as preparation margin or cavosurface
margin.
Line Angle
It is a junction of two surfaces of different orientations
along the line and its name is derived from the involved
surfaces.
Point Angle
It is a junction of three plane surfaces or three line angles of
different orientation and its name is derived from its involved
surfaces or line angles.
المحاضرة الاولى.pdf

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المحاضرة الاولى.pdf

  • 2. Operative dentistry is defined as science and art of dentistry which deals with diagnosis, treatment and prognosis of defects of the teeth which do not require full coverage restorations for correction”. Such corrections and restorations result in the restoration of proper tooth form, function and aesthetics while maintaining the physiological integrity of the teeth in harmonious relationship with the adjacent hard and soft tissues. Introduction
  • 3. Indications of operative dentistry procedures ❖ Caries Dental caries is an infectious microbiological disease of the teeth which results in localized dissolution and destruction of the calcified tissue ❖ Noncarious Loss of the Tooth Structure due to Attrition, Abrasion, Abfraction and Erosion Attrition Mechanical wear between opposing teeth commonly due to excessive masticatory forces. Abrasion Loss of tooth material by mechanical means other than by opposing teeth. Erosion Loss of dental hard tissue as a result of a chemical process not involving bacteria.
  • 4. Indications of operative dentistry procedures ❖ Malformed, Traumatized, or Fractured Teeth Traumatic injuries may involve the hard dental tissues and the pulp which require restoration. ❖ Esthetic Improvement Discolored teeth because of staining or other reasons look unesthetic and require restoration. ❖ Replacement or Repair of Restoration Repair or replacement of previous defective restoration is indicated for operative treatment.
  • 5. Scope of Operative Dentistry Scope of operative dentistry includes the following: • To know the condition of the affected tooth and other teeth. • To examine not only the affected tooth but also the oral and systemic health of the patient. • To diagnose the dental problem and the interaction of problem area with other tissues. • Provide optimal treatment plan to restore the tooth to return to health and function. • Thorough knowledge of dental materials which can be used to restore the affected areas. • To maintain the pulp vitality and prevent occurrence of pulpal pathology. • To have knowledge of dental anatomy and histology. .
  • 6. Purpose of operative dentistry Diagnosis Proper diagnosis is vital for treatment planning Prevention To prevent any recurrence of the causative disease and their defects Interception Preventing further loss of tooth structure by stabilizing an active disease process..
  • 7. Preservation Preservation of the vitality and periodontal support of remaining tooth structure. Restoration Includes restoring form, function, phonetics and aesthetics. Maintenance After restoration is done, it must be maintained for providing service for longer duration. Purpose of operative dentistry
  • 8. TERMINOLOGY OF TOOTH PREPARATION It is the mechanical alteration of a defective, injured or diseased tooth in order to best receive a restorative
  • 9. Simple Tooth Preparation A tooth preparation involving only one tooth surface is termed simple preparation for example occlusal preparation.
  • 10. Compound Tooth Preparation A tooth preparation involving two surfaces is termed compound tooth preparation for example mesioocclusal or disto-occlusal preparation.
  • 11. Complex Tooth Preparation A tooth preparation involving more than two surfaces is called as complex tooth preparation for example MOD preparation.
  • 12. Tooth Preparation Walls Internal Wall It is a wall in the preparation, which is not extended to the external tooth surface
  • 13. External Wall:- An external wall is a wall in the prepared tooth that extends to the external tooth surface. External wall takes the name of the tooth surface towards which it is situated. Tooth Preparation Walls
  • 14. Tooth Preparation Walls Pulpal Wall:- A pulpal wall is an internal wall that is towards the pulp and covering the pulp. It may be both vertical and perpendicular to the long axis of tooth.
  • 15. Tooth Preparation Walls Axial Wall:- It is an internal wall which is parallel to the long axis of the tooth .
  • 16. Floor:- Floor is a prepared wall which is usually flat and perpendicular to the occlusal forces directed occlusogingivally,for example, pulpal and gingival walls . Tooth Preparation Walls
  • 17. Cavosurface Angle Margin/Tooth Preparation Margin Cavosurface angle is formed by the junction of a prepared tooth surface wall and external surface of the tooth .The acute junction is referred to as preparation margin or cavosurface margin. Line Angle It is a junction of two surfaces of different orientations along the line and its name is derived from the involved surfaces. Point Angle It is a junction of three plane surfaces or three line angles of different orientation and its name is derived from its involved surfaces or line angles.