dentin bonding agents

explained with Limited matter moreover I have included all the images. if you go through a standard textbook and referred to this PPT it will help you so much I hope It helps you

1. CONTENTS Introduction Definition Factors affecting Conditioning Bonding to dentin Priming Dentin bonding agents Mechanism Evolution Role of water Bonding in other clinical situations Additives Success/failure Water treeing Conclusion References DENTIN BONDING AGENTS

2. INTRODUCTION Major Problem – Proper Union Gap – Create Problems Process Of Inventions – Various Techniques And Modalities BONDING Adhesive techniques Adhesive agents

3. BASIC PRINCIPLES Adhesive Substance added to produce adhesion Adherend Material to which it is applied Adhesion force or the intermolecular attraction Factors affecting SURFACE ENERGY WETTING CONTACT ANGLE

4. TOOTH AS A SUBSTRATE FOR BONDING Contrast in composition of enamel and dentin influence the bonding Presence of moisture in dentin Dentinal fluid- outward flow Moisture – external factors Important factor – smear layer Smear unit - contaminant

5. Requisite of an ideal bonding agent High bond strength to dentin . Biocompatibility. Minimize micro leakage. Prevent recurrent caries and marginal staining. Easy to use and minimally technique sensitive. Good shelf life. Be compatible with a wide range of resins. Non toxic and non sensitizing. seal the tooth surfaces from oral fluids.

6. Objective – remove contaminants, raise energy Conditioning – remove organic layer Etching – demineralization Removes – pellicle & surface enamel Creates porous layer Increase wettability , surface area & surface energy Conditioning enamel and etching

7. PATTERNS OF ETCHING IN ENAMEL Etched surface – matt white / frosty Other alternatives Recent advances 37% PA – most common Time – 10-15 seconds

8. BONDING TO DENTIN Comparatively difficult – Complex tissue Living tissue Direct connection – pulp Bonding of resin composite-dentin Micromechanical attachment Treatment of dentin for optimal bonding Conditioning of dentin Role of smear layer Priming

9. DENTIN BONDING AGENTS

10. WATER TREEING PHENOMENON This phenomenon does not occur in self etching primers because the etched and primed dentin is covered by a comparatively thick hydrophobic resin layer In such a case a resin modified glass ionomer is used before placing composite restorations.

11. REFERENCES Sturdevant’s art and science of operative dentistry Philips science of dental materials Pickards manual of operative dentistry Materials used in dentistry mahalakshmi Buonocore MG, Wileman W, Brudevold F: Simple methods of increasing adhesion of acrylic filling materials to enamel surfaces, J Dent Res 34(6):849, 1955 Asmussen E: Clinical relevance of physical, chemical and bonding properties of composite resins, Oper Dent 10:61, 1985 CONCLUSION Dentin bonding agents have dramatically improved in recent years. The major breakthrough has been the “total etch” technique, in which the smear layer is removed simultaneously with the enamel etching. The primers and bonding agents of multicomponent systems and combined primer/agent of one-bottle systems provide a dramatic bond to both the collagen and etched hydroxyapatite of the dentin. Although dentin bonding agents are not yet considered “ideal” materials, they are certainly close. Hopefully more controlled clinical trials will be forthcoming, allowing choices of material and technique to be made on a sound scientific basis.

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