1. http:// www.dent.unc.edu/ portfolios/ bayne/ dental-materials/
VARNISH, LINERS, and BASES
Stephen C. Bayne
DENT112
Conservative Operative Dentistry
School of Dentistry
University of North Carolina
Roberson TM. Sturdevant's Art and Science of Operative Dentistry, 4:
portfolios/ bayne/ dental-materials/
 2006, Bayne and Thompson

2. OVERVIEW OF PULPAL PROTECTION
PROBLEM = No perfect replacement for missing enamel and dentin.
NORMAL
RESTORED
CHEMICAL Protection
PULPAL Medication
THERMAL / ELECT Protection
MECHANICAL Protection
SOLUTION LINER = thin film (varnish, bonding system, dentin sealer)
Suspension Liner (20-25 mm)
CEMENT LINER = medium thickness ( mm)
CEMENT BASE = thick ( mm)

3. FLUID FLOW = J = (P) (r4) / (8) (h) (l)
PULPAL
PROBLEMS:
Fluid Flow
Microleakage
Occlusion of
tubules

4. CHEMICAL PROTECTION DEFINITIONS:
Varnish = thin film solution liner (hydrophobic)
Suspension liner = thin film aqueous liner (hydrophilic)
Bonding system = thin film solution liner (hydrophilic)
Dentin sealer = thin film solution liner (hydrophilic)
Copalite
Smear Layer on Dentin
COPALITE = 90% solvent + 10% copal resin
Hydrophobic and does not wet dentin well.
Requires 2 applications for 85% coverage.
Thin coats work best.

5. (Biological Protection)
PULPAL MEDICATION
(Biological Protection)
PULPAL
PROBLEMS:
Fluid Flow
Microleakage
DENTIN
FUNCTIONS:
Chemical Protection
Thermal / Electrical Protection
Biological Protection (Medication)
Mechanical Protection
RDT
1º Dentin
2º Dentin
3º Dentin

6. (Biological Protection with Eugenol or Calcium Hydroxide)
PULPAL MEDICATION
(Biological Protection with Eugenol or Calcium Hydroxide)
PULPAL
PROBLEMS:
Fluid Flow
Microleakage
DENTIN
FUNCTIONS:
Chemical Protection
Thermal / Electrical Protection
Biological Protection (Medication)
Mechanical Protection
pH = 11.0
Low strength
Ca ion + salicylate
and ZnO ( Zn++)
Eugenol
Palliative
Ca(OH)2
Stimulating

7. THERMAL PROTECTION Intraoral HEAT FLOW:
Normal thermal transient = 30-60s at 5-60°C
HEAT paths = through restoration or via microleakage
Pulpal temperature = f ( TIME, TEMP, THICKNESS )
RDT
Through
restoration:
Thermal Conductivity
Thermal Diffusivity
Around
restoration:
Thermal Expansion

8. MECHANICAL PROTECTION
PROTECTION = 1-2 mm ( mm)
> Chemical Protection (Sealed tubules)
> Biological Protection (Pulpal Medication)
> Thermal / Electrical Protection (1-2 mm)
> Mechanical Protection (BASE = 1-2 mm)
RMGI
Polycarboxylate
Zinc Phosphate

9. BASES

10. of Varnishes, Liners, and Bases
COMMERCIAL EXAMPLES
of Varnishes, Liners, and Bases

11. for Medicament, Liner/Base, Varnish/Sealer/DBS
PROCEDURE SUMMARY
for Medicament, Liner/Base, Varnish/Sealer/DBS
RDT =