Tooth Restorations

Chapter Objectives By the end of this chapter, you should be able to:

• Discuss the purpose of dental restorations and their classifications, and identify the steps of the dental restoration procedure.

• List the various methods employed to maintain a dry mouth area during dental preparations.

• Name the steps in preparing a restorative site prior to placing the restorative materials.

• Discuss the necessity for matrix placement, and identify the various types of matrix retainers and their uses.

• Identify and describe the assorted dental cements, liners, and base materials used in tooth restorations.

• Understand and define terminology commonly used in dental restorative procedures.

• Discuss the various types and properties of dental restorative materials used in tooth restorations.

• Identify the methods used to complete, finish, and refine the tooth restoration.

Operatory and Procedure Area

• Steps in restoration:

  • Remove decay. This involves using dental instruments to carefully eliminate the decayed portion of the tooth, preventing further spread of the caries.

  • Prepare restorative site. Preparing the site ensures optimal bonding and adaptation of the restorative material.

  • Classification of caries: (Class I - Class VI)

  • Class I: Pits and fissures on the occlusal surfaces of molars and premolars, buccal or lingual pits of molars, and lingual pits of maxillary incisors.

  • Class II: Involves the proximal (mesial or distal) surfaces of premolars and molars.

  • Class III: Involves the proximal surfaces of incisors and canines that do not involve the incisal angle.

  • Class IV: Involves the proximal surfaces of incisors or canines that do involve the incisal angle.

  • Class V: Occurs on the facial or lingual surfaces of any tooth at the gingival third (near the gumline).

  • Class VI: Involves the incisal edges of anterior teeth or the occlusal cusp heights of posterior teeth.

  • Restore tooth to normal function. This ensures the tooth can properly perform its role in chewing and speaking, maintaining dental arch integrity.

Isolation of the Operative Site

• Dry field: Maintaining a dry field is crucial for successful dental restorations, preventing contamination and ensuring proper bonding of materials.

  • Oral evacuation: Use of high-volume evacuation (HVE) and saliva ejectors to remove fluids and debris from the mouth.

  • Saliva ejector: A low-volume suction device used to remove saliva and small amounts of fluid from the mouth.

  • Absorbent pads: Cotton rolls or dry angles are placed to absorb saliva and maintain dryness in specific areas.

• Isolation:

  • Barrier: Use of physical barriers to isolate the operative site from the rest of the mouth.

  • Dental dam: A thin latex or non-latex sheet used to isolate one or more teeth during a dental procedure.

  • Ligature: Floss or rubber dam clamps used to secure the dental dam around the teeth.

  • Invert: Folding the edges of the rubber dam around each tooth to create a tight seal.

  • Stabilize: Ensuring the dental dam remains securely in place throughout the procedure.

Preparation of the Restorative Site

• Removal of caries and perform debridement: Thoroughly cleaning the tooth to remove all decay and debris, ensuring a clean surface for restoration.

• Preparation of tooth form:

  • Outline: Establishing the ideal shape and dimensions of the restoration.

  • Convenience: Modifying the tooth structure to allow easier access and placement of restorative materials.

  • Retention: Creating features in the tooth preparation to mechanically lock the restoration in place.

  • Resistance: Designing the preparation to withstand occlusal forces and prevent displacement of the restoration.

  • Finishing and refinement: Smoothing and shaping the restoration to match the natural tooth contours and ensure proper function.

Matrix Placement

• Types of matrices:

  • T-strip: A simple matrix band used for Class II restorations, especially in primary teeth.

  • Tofflemire: A universal matrix retainer used to hold the matrix band in place around the tooth.

  • AutoMatrix: A pre-assembled matrix system that does not require a retainer.

  • Ivory retainer: A specific type of retainer used with matrix bands for Class II restorations.

  • Sectional: Used for composite restorations to help establish proximal contact and contour.

  • V3 system or spring clamp: A type of sectional matrix system that uses a spring clamp to hold the matrix in place.

  • Mylar matrix and crown forms: Thin, transparent strips used for composite restorations, especially on anterior teeth.

Cements, Liners, and Base Materials

• Varnish: A thin layer applied to the prepared tooth surface to reduce microleakage and sensitivity.

• Liner: A thin layer of material placed on the deepest portion of the cavity preparation to protect the pulp.

• Acid etchant: A solution used to create a micro-retentive surface on enamel and dentin for bonding.

• Bonding agent: A resin material used to bond the restorative material to the tooth structure.

• Base: A thicker layer of material placed under a restoration to provide thermal insulation and support.

• Cement: A material used to lute or bond indirect restorations to the prepared tooth.

• Retention pin: Small metal pins used to provide additional retention for large restorations.

• Core post: A post placed in the root canal of a tooth to provide retention and support for a core buildup.

Purposes of Liners, Bases, and Cements

• Insulation: Providing a barrier against thermal sensitivity.

• Palliative: Soothing and protecting the pulp.

• Protective: Shielding the pulp from chemical irritation.

• Luting: Cementing indirect restorations in place.

• Cementation of restorative pins: Securing retention pins within the tooth structure.

• Laminated: Applying materials in layers to achieve desired properties and aesthetics.

Restoration Placement Terminology

• Manipulation: The process of mixing and handling dental materials according to manufacturer instructions.

• Homogenous: Uniform consistency throughout a mixture.

• Trituration: The mechanical mixing of amalgam alloy and mercury.

• Mulling: Further blending of the amalgam after trituration to achieve a smooth, homogenous mix.

• Dissipate: To spread out or disperse heat generated during a chemical reaction.

• Polymerization: The chemical process in which monomers are converted into a polymer.

• Bonding: The process of attaching a restorative material to the tooth structure using adhesive techniques.

Restorative Materials

• Amalgam: A metallic alloy used for direct restorations, known for its strength and durability.

• Cement: A broad category of materials used for various purposes, including luting and base applications.

• Composite: A tooth-colored resin material used for direct and indirect restorations.

• Gold foil: Pure gold used for direct restorations, known for its excellent biocompatibility and longevity.

• Veneer: A thin layer of porcelain or composite resin bonded to the facial surface of a tooth to improve its appearance.

Finishing Methods

• Increment: Placing restorative material in small layers to minimize shrinkage and improve adaptation.

• Condensation: Packing the restorative material tightly into the preparation to reduce voids and improve density.

• Carving: Shaping the restorative material to match the natural tooth anatomy.

• Burnish: Smoothing the surface of the restoration to improve its luster and reduce marginal discrepancies.

• Articulating paper: Used to check the occlusion (bite) and identify areas of premature contact.

• Laminated: Applying materials in layers to achieve desired properties and aesthetics.

• HVE: High-volume evacuation to remove debris and maintain a clear field during finishing procedures.