Dentin Bonding agents generations

bonding agents in dentistry , definition, mechanism and generations

1. Bonding agent generations DEFINITION,MECHANISM AND GENERATIONS BY : Farah Sarmad Dental student /4th stage At university of baghdad

2. DEFINITION are  resin  materials used to make a  dental composite  filling material adhere to both   dentin  and  enamel . IT IS CONSISTS OF : PMMA( POLY METHYL METHACRYLATE ) volatile carrier solvent like  acetone They may also contain  diluent  monomers.  

3. MECHANISMS OF ACTION ETCH PRIMER BONDING AGENT PARTIAL\TOTAL REMOVAL OF SMEAR LAYER. DEMINERALIZATION OF INTERTUBULAR & PERITUBULAR DENTIN. DENTINAL TUBULES OPENED WHILE EXPOSING COLLAGEN FIBERS. MICROPOROSITY OF INTERTUBULAR DENTIN INCREASED. INCREASE THE CRITICAL SURFACE TENSION OF DENTIN . PENTERATE THE INTERTUBULAR DENTIN & FORMING HYBRID LAYER. PENTERATE & POLYMERIZE IN OPEN DENTINAL TUBULES &FORMING RESIN TAGS.

4. FOURTH GENERATION (THREE STEP ADHESIVE) etchant primer adhesive

5. Etchant ( phosphoric acid in gel form ) Primer : is a bifunctional molecule consist of hydrophilic ( monomers in ethanol , acetone & water attaches to the tooth ) . hydrophobic monomer attaches to the composite resin . Examples : HMA NTG-GMA PENTA Bonding agent: consist of unfilled & filled resins BisGMA , UDMA with TEGDMA & HEMA . Aids in penetration into intertubular dentin to form a resin dentin inter diffusion zone called HYBRID LAYER .

6. advantages Higher bond strength of 17-24MPa Reliable and consistent results DISADVANTAGES Technique sensitive Time consuming procedure Over wetting or over drying of dentin BRAND NAMES All bond 2 & All bond 3 Optibond FL ( Kerr corporation) 3M ESPE

7. Total etchant for 15 sec Rinse the etchant thoroughly +blot dry primer Adhesive Light cure

8. FIFTH GENERATION TWO STEPS PRIMER & ADHESIVE ETCHANT

9. ETCHANT GEL RINSE THE ETCHANT THOROUGHLY & BLOT DRY THE SUBSTRATE (MOIST TECHNIQUE) PRIMER + ADHESIVE ( SINGLE BOTTLE ) LIGHT CURE

10. Prime&bond NT( Dentsply Adper single bond 2 ExciTE ( ivoclar,vivadent ) XP bond One caot bond

11. SISTH GENERATION 2 STEPS & 2 COMPONENT 1 STEP & 2 COMPONENT

12. VI GENERATION 2 STEPS & 2 COMPONENT NOURSHING CONDITIONER OR SELF PRIMER ETCHANT MECHANISM OF ACION:- THE ACIDIC PRIMERS CONTAIN PHOSPHATED RESIN MOLECULES PERFORMS FUNCTIONS:- ETCHING & PRIMERING OF ENAMEL . INCORPORATING SMEAR PLUGS INTO RESIN TAGS.

13. APPLICATION OF BOTTLE 1 ETCHANT+ PRIMER AFTER 10S ,APPLY BOTTLE 2 ON TOOTH SURFACE LIGHT CURE

14. Clearfil SE bond( kuraray,japan ) A dheSE (ivoclar, vivadent ) Optibond Solo Plus Self-etch (kerr corp )

15. SIXTH generation 1 step & 2 component Bottle 1 Conditioner +primer Bottle 2 Adhesive resin

16. Self etching primers are acidic in nature leading to it’s penetration along the aqueous channels found in smear layer and widening them. When the concentration of acidic monomers increased (30-40% in VI) aided in etching through smear layer . Self etching primers contain acidic esters like HEMA,MDP,TEGDMA . Simpler than that of total etchant adhesive systems. BRANDS Xeno III( Dentsply ) One Up bond ( tokuyama ) Prompt L bond (3M ESPE)

17. NO ETCHING NEEDED. LESS TECHNIQUE SENSITIVE. LESS TIME CONSUMING . S ELF ETCH ADHESIVES ARE LESS LIKELY TO RESULT IN DISCREPANCY BETWEEN DEPTH OF DEMINERALIZATION AND DEPTH OF INFILTRATION. DECREASE SHELF LIFE. INCOMPATIBLE WITH CHEMICAL CURE COMPOSITE. SELF ETCH ADHESIVES ARE CURRENTLY AVAILABLE DO NOT ETCH AS EFFECIENTLY AS PHOSPHORIC ACID ESPECIALLY IF THE ENAMEL HAS NOT BEEN INSTRUMENTED .

18. Seventh generation self etching adhesive The etchant,primer & adhesive resin are combined in one bottle . Advantage:- Lesser application time. Decrease in errors with etch step. Disadvantages :- Tooth-restoration interface created do not eliminate the micro leakage & bacterial penetration which cause secondary caries .

19. iBond ( heraeus kulzer ) G bond ( GC ) Xeno IV( dentsply ) Clearfil S3(curare) Xeno v+

20. Can be used with self-etch , selective-etch & total_etch technique. Can be used with dual- cure , self-cure & light-cure without need to separate activator. Can be used for both direct and indirect substrates. The adhesive MDP monomer contained in most universal adhesives enables effective bonding to calcium, dentin, enamel, zirconia and metal alloys

21. The first universal adhesive has a 100% retention rate after three years with a total-etch approach. Scotchbond Universal from 3M was the first universal adhesive introduced. It has the 10 MDP Monomer. Universal adhesives have a higher pH level than other adhesives, Phosphoric acid etches enamel well and “ enamel likes an aggressive etch .” The application techniques are simplified with universal adhesives . curing light matters-a lot . Universals are much more resistant to contamination than their predecessors. Universals have a separate bonding mechanism in addition to the hybrid layer formation. All bonding agents create a hybrid layer consisting of collagen encased adhesive but the US creating a chemical bond from the 10 MDP monomers to the calcium in the tooth. This makes the bond more durable-and getting more so all the time . Most universals bond well to zirconia.