Dental Adhesion Principles and Practices

Dangerous Materials

• Adhesion: Essential for dental treatments such as crowns, bridges, veneers, and braces.

Adhesion Principles

• Preparation: Involves removing plaque and debris, followed by etching with phosphoric acid (10-38%).
• Etching: Increases the surface area for better resin contact, enhancing adhesion.
• Enamel: Composed of hydroxyapatite crystals (95% inorganic), water (0.36%), and organic matrix (3-5%).
• Dentin: The main component of the tooth structure, made of mineralized tissue.

Adhesion Force

• Definition: The force required to separate two bonded surfaces, which can be measured.
• Formula: 1 MPa = 10.2 kg/cm²

Enamel Etching

• Duration: Takes about 20 to 30 seconds, but may vary depending on the procedure.

Dentin Etching

• Procedure: Involves removing debris from the tooth surface using rotary instruments.

Adhesion Agents

• Types: Resin composites for enamel, dentin, total etching, oxygen inhibition, and self-etching.
• Classification: Categorised into total etching and self-etching systems.
• Tools: Specific etching tools are used in general, but self-etching systems can be applied directly.
• Note: Some systems only require enamel etching for materials like enamel.

Materials for Aesthetic Direct Placement

• Materials: Direct Placement Resin, Composite Resin, Glass Ionomer Cement, Hybrid Ionomer, and Compomer.

Composite Resins

• Color: Matched to the color of both anterior and posterior teeth.
• Formation: Composed of organic resin matrix (polymer) and inorganic fillers (silica) joined by a silane coupler.
• Adjustments: Accelerators and pigments can be added to achieve the desired tooth color.

Composite Resin Components

• Resin Matrix: Bis-GMA is the most common resin used.
• Resin Liquids: Oligomeric formations with 2 or more monomers.
• Fillers: Mostly inorganic (silica) to increase strength and reduce shrinkage during polymerization.
• Filler Content: Higher filler content leads to stronger restorations.

Agente Acoplador

• Function: Silane is a coupling agent that improves adhesion between organic fillers and the resin matrix by reacting with the surface of the inorganic filler and the organic matrix to create a stronger bond.

Pigmentos

• Purpose: Matching the natural tooth color.
• Examples: Chromium, saturation.
• Color Charts: A1, B1, ... An, Bn

Polimerización

• Definition: Chemical reaction where low molecular weight resin molecules (monomers) join to form polymers.
• Methods: Composite resins can be polymerized through chemical means, light, or a combination of both.

Curación Química

• Systems: Two-step systems with a base (containing the resin) and an initiator, and a separate catalyst.

Fotocuración

• Method: The most common method, as it doesn't require mixing.
• Light: Blue light with a wavelength close to 470 nm activates the initiator, triggering polymerization.
• Factors: Light access and resin layer thickness affect curing capacity.

Curación Doble

• Systems: Two step systems with initiators and activators, activated by both light and chemically.
• Advantage: Continued chemical reaction where light does not reach.

Cement de Conomero de Vidrio (CIV)

• Uses: Luting agents, restorative materials, base and liner, cavity lining, fissure sealing, non-traumatic restorative treatments.

CIV: Precautions

• Insufficient light emission.
• Poor setting/ generation of heat.
• Eye protection is essential.

CIV: Physical Properties

• Biocompatibility: Compatible with pulp.
• Adhesion: Adheres to the dental structure.
• Fluoride Release: Releases fluoride into the surrounding tooth structure.
• Solubility: Sensitive to water absorption and release.
• Thermal Expansion: Affected by changes in temperature.
• Thermal Protection: Provides protection against thermal changes.
• Compressive Strength: High compressive strength.
• Tensile Strength: Lower tensile strength compared to compressive strength.
• Resistance to Wear: Wears faster than resin.
• Radiopacity: More radiopaque than resin.
• Color: More opaque than resins.

Types of Hybrid Ionomers

• Improvements in glass ionomer (GI) properties: enhanced wear resistance and aesthetics.

Composites

• Contain modified/polyacid resins.
• Setting reactions occur in two phases.
• Form a network structure similar to light-activated composites.

Glass Ionomer (IV)

• Result of mixing aqueous liquids (carboxylic acid) with powdered polyalkenoates.
• Basic Composition:
  • Glass Powder: Silica, Alumina, and Fluorocalcium
  • Acidic Polymer (Liquid): Polyacrylic acids, tartaric and tannic acids.

Setting/Fraguado Reaction (IV)

• Acid-base reaction involving mixing a powder and a liquid.
• Matrix Formation: Through a union of the two components.
• Reaction Stages: Three distinct stages.
• Final Result: Involves ion displacement.

Reaction of Hardness:

• Hardness: Related to the exchange of C and carboxylic group.
• Reaction: Acid-Base.

Water:

• Influence: Plays a crucial role in ionic exchange, occurring in aqueous media.
• Deficiency or Excess: Causes structural changes (drying/erosion).
• Plasticizer: Acts as a plasticizer, reducing rigidity.

Cleaning:

• Treatments: Topical application of fluoride, bleaching, and decontamination.

Explore the crucial principles behind dental adhesion, including preparation and etching methods for both enamel and dentin. This quiz covers adhesion forces, types of adhesion agents, and specific procedures involved in dental treatments. Test your understanding of these essential concepts in dentistry.