Understanding Dental Materials for Oral Health

OVERVIEW OF OVERVIEW OF DENTAL MATERIALS DENTAL MATERIALS

What is Dental Material? Human body is prone to damage due to either disease or accidents. Likewise the structures in the oral cavity are lost or damaged due to disease such as caries, periodontal disease and trauma. The main goal in dentistry is to maintain or improve the quality of life through replacement or alteration of tooth structure.

s Goal can be accomplished by preventing disease, relieving pain, improving mastication efficiency, enhancing speech, & improving appearance. Therefore the main challenge for centuries has been to develop and select ideal dental materials that can withstand the adverse conditions of the oral environment.

Ideal Restorative Material Be biocompatible Should bond permanently to tooth structure or bone Should match the natural appearance of tooth structure and other visible tissues Exhibit properties similar to those of tooth tissues (enamel and dentine) Be capable of initiating tissue repair or regeneration of missing or damaged tissues

DENTAL MATERIALS Metals Ceramics Polymers Composites

Classification Preventive dental materials Restorative dental materials Auxiliary dental materials

Preventive Dental Materials Pit and Fissure Sealants Sealing agents that prevent leakage Materials used primarily for their antibacterial effects. Liners, bases, cements and restorative materials that are used primarily because they release fluoride. Chlorhexidine or other therapeutic agents used to prevent or inhibit the progression of tooth decay.

Restorative Dental Materials Synthetic components that can be used to repair or replace tooth structure, including primers, bonding agents, liners, cement bases, amalgams, resin-based composites, compomers, hybrid ionomers, cast metals, metal-ceramics, ceramics, and denture polymers.

Restorative Dental Materials Direct restorative materials Used intraorally to fabricate restoration or prosthetic devices directly on the teeth Indirect restorative materials Made extraorally in which the materials are formed indirectly on the teeth or tissues Temporary restorative materials

Auxiliary Dental Materials Substances used in the process of fabricating dental prostheses and appliances but do not become part of these devices. Acid etch solutions, impression materials, casting investments, gypsum cast, and model materials, dental waxes, acrylic resins for impression, bleaching trays, mouthguards, and occlusion aids, finishing and polishing abrasives.

Terminologies Restoration- filling material or prosthesis used to restore or replace a tooth, a portion of a tooth, multiple teeth, or other oral tissues

DIRECT FILLLING GOLD

Base- layer of insulating, sometimes medicated, cement, placed in the deep portion of the preparation to protect pulpal tissue from thermal and chemical injury Cement- substance that hardens to act as a base, liner, filling material, or adhesive to bind devices and prosthesis to tooth structure or to each other

Zinc polycarboxylate cement Zinc Phosphate cement

Cavity liner- thin layer of cement, such as Ca(OH)2 suspension in an aqueous or resin carrier(after evaporation)used for protection of the pulp. certain glass ionomer cements that are used as an intermediate layer between tooth structure and composite restorative material are also considered liners.

Intermediate restorative material Zinc oxide eugenol

DIRECT RESTORATIVE MATERIALS Amalgam Liners and bases Varnishes, calcium hydroxide, zinc oxide eugenol, zinc phosphate, zinc polycarboxilate, glass ionomer cement Pit and fissure sealants Composites Glass ionomer cement Direct filling gold

Properties of dental materials Coefficient of thermal expansion Contact angle Strength- - Compressive strength - Tensile strength - Shear strength Modulus of elasticity Abrasion resistance biocompatibility

Amalgam Compressive strength Tensile strength Creep Dimensional stability Tarnish and corrosion expansion

Composites Compressive strength Tensile strength Modulus of elasticity esthetics Polymerization shrinkage Modulus of elasticity biocompatibility

INDIRECT RESTORATIVE MATERIALS Impression materials Cast metal restorations Ceramic restorations Cementation materials

IMPRESSION MATERIALS

CAST METAL RESTORATIONS

METAL CROWN