Operative Lec. 1 Introduction PDF

Operative Lec. 1 Introduction (Definition, Classifications, Principles) Operative Lec. 1 Dr. Faisal Alhuwaizi  Operative Dentistry Lecture Subject...

Operative Lec. 1 Introduction (Definition, Classifications, Principles) Operative Lec. 1 Dr. Faisal Alhuwaizi  Operative Dentistry Lecture Subject Lec. 1 Introduction (Definition, Classifications, Principles) Lec, 2 Dental Rotary And Hand Instruments Lec. 3 Sterilization Lec. 4 Classifications of cavities + Class I Amalgam Restorations Lec. 5 Class II Amalgam Restorations Lec. 6 Class III Amalgam Restorations Lec. 7 Class V Amalgam Restorations Operative Lec. 1 Dr. Faisal Alhuwaizi Before we start.. Restorative Dentistry: is a dental service in which decayed , fractured or missing teeth are repaired by artificial materials. The restorative section is divided into 3 branches: 1- Operative dentistry, is the art and science of the diagnosis, treatment, and prognosis of defects of teeth that do not require full coverage restorations for correction (e.g. amalgam and composite restorations). Operative Lec. 1 Dr. Faisal Alhuwaizi 2- Fixed-prosthodontics, where crowns and fixed partial dentures (bridges) are fabricated, fitted, and cemented into place. 3- Endodontics, the treatment of dental pulps, and the filling of root canals. Operative Lec. 1 Dr. Faisal Alhuwaizi  Definition Of Tooth Preparation Tooth preparation is defined as the mechanical alteration of a defective, injured, or diseased tooth to best receive a restorative material that will re-establish a healthy state for the tooth with normal form and function. Operative Lec. 1 Dr. Faisal Alhuwaizi  Objectives Of Tooth Preparation In general terms, the objectives of tooth preparation are to: 1) To remove diseased tissue as necessary and provide necessary protection to the pulp. 2) To restore the integrity of the tooth surface. 3) To restore the function of the tooth- (so that under the force of mastication the tooth or the restoration or both will not fracture and the restoration will not be displaced. 4) To restore the appearance of the tooth. Operative Lec. 1 Dr. Faisal Alhuwaizi  Indications for Operative Procedures They can be categorized into three primary treatment needs: 1) Caries. 2) Malformed, discolored, or fractured teeth. 3) Restoration replacement or repair. Operative Lec. 1 Dr. Faisal Alhuwaizi  Nomenclature It refers to a set of terms used in communication by persons in the same profession that enables them to better understand one another. CARIES TERMINOLOGY Dental caries is an infectious microbiologic disease that results in localized dissolution and destruction of the calcified tissues of the teeth. Operative Lec. 1 Dr. Faisal Alhuwaizi  Morphologic types of caries Carious lesions originating: (1) On enamel pits and fissures. (2) On enamel smooth surfaces. (3) On root surfaces (Senile caries). Operative Lec. 1 Dr. Faisal Alhuwaizi (1) Caries on Enamel Pits and Fissures Origin. The caries forms a small area of penetration in the enamel at the bottom of a pit or fissure and does not spread laterally to a great extent until the dentino-enamel junction (DEJ) is reached. In diagrammatic terms, pit-and-fissure caries may be represented as two cones, base to base, with the apex of the enamel cone at the point of origin and the apex of the dentin cone directed toward the pulp. Operative Lec. 1 Dr. Faisal Alhuwaizi (2) Caries of Enamel Smooth-Surface Origin. The disintegration in the enamel in smooth-surface caries also may be pictured as a cone, but with its base on the enamel surface and the apex at, or directed to, the DEJ. The caries again spreads at this junction in the same manner as in pit-and-fissure caries. Thus, the apex of the cone of caries in the enamel contacts the base of the cone of caries in the dentin. (Double inverted cone). - Contact Areas. Operative Lec. 1 Dr. Faisal Alhuwaizi (3) Root surface caries. The proximal root surface, near the cervical line, often is unaffected by the action of hygiene procedures, such as flossing, because it may have concave anatomic surface contours and occasional roughness at the termination of the enamel. These conditions, when coupled with exposure to the oral environment (gingival recession), favor the formation of caries- producing plaque and proximal root-surface caries. Operative Lec. 1 Dr. Faisal Alhuwaizi  Root-surface caries is more common in older patients. Why? Caries originating on the root is alarming because: - It has a comparatively rapid progression. - It is often asymptomatic. - It is closer to the pulp. - It is more difficult to restore. Operative Lec. 1 Dr. Faisal Alhuwaizi  Tooth Preparation Terminology A tooth preparation is termed: 1- Simple if a tooth preparation only one tooth surface is involved. 2- Compound if a tooth preparation two surfaces are involved. 3- Complex if a tooth preparation involving three (or more) surfaces. Operative Lec. 1 Dr. Faisal Alhuwaizi  Abbreviated Descriptions of Tooth Preparations. The description of a tooth preparation is abbreviated by using the first letter, capitalized, of each tooth surface involved. Examples are: (1) an occlusal tooth preparation is an O. (2) a preparation involving the mesial and occlusal surfaces is an MO. (3) a preparation involving the mesial, occlusal, and distal surfaces is an MOD. Operative Lec. 1 Dr. Faisal Alhuwaizi  Tooth Preparation Walls (1) Internal Wall: An internal wall is a prepared (cut) surface that does not extend to the external tooth surface. (2) Axial wall: An axial wall is an internal wall parallel with the long axis of the tooth (3) Pulpal wall: A pulpal wall is an internal wall that is both perpendicular to the long axis of the tooth and occlusal of the pulp. Operative Lec. 1 Dr. Faisal Alhuwaizi (4) External Wall: An external wall is a prepared (cut) surface that extends to the external tooth surface, and such a wall takes the name of the tooth surface (or aspect) that the wall is toward. Operative Lec. 1 Dr. Faisal Alhuwaizi  Tooth Preparation Walls (5) Floor (or Seat): is a prepared (cut) wall that is reasonably flat and perpendicular to the long axis of the tooth). Examples are the pulpal and gingival walls. Operative Lec. 1 Dr. Faisal Alhuwaizi  Tooth Preparation Angles The junction of two or more prepared (cut) surfaces is referred to as an angle. - Line Angle: A line angle is the junction of two planal surfaces of different orientation along a line. An internal line angle is a line angle whose apex points into the tooth. An external line angle is a line angle whose apex points away from the tooth. - Point Angle: A point angle is the junction of three planal surfaces of different orientation. Operative Lec. 1 Dr. Faisal Alhuwaizi  Tooth Preparation Angles Cavo-surface Angle and Cavo-surface Margin: Is the angle of tooth structure formed by the junction of a prepared (cut) wall and the external surface of the tooth. The actual junction is referred to as the cavo-surface margin. Proximal surface: is the surface that face the adjacent tooth. Marginal ridge: border the lingual surface of anterior teeth and the occlusal surfaces of posterior teeth Operative Lec. 1 Dr. Faisal Alhuwaizi   Operative Lec. 1 Dr. Faisal Alhuwaizi  Thank you Operative Lec. 1 Dr. Faisal Alhuwaizi