The document discusses various techniques and materials for posterior composite restorations, including the use of liners to reduce marginal leakage and polymerization shrinkage stress. It also covers advances in dental adhesives that incorporate solvents and nanoparticles to improve bonding to dentin. Proper layering of composites incrementally is recommended to minimize shrinkage and debonding at restoration interfaces.

1. Posterior
Composites

2. ALLAH’S Thought at all times

3. Fazal ur Rehman Qazi
BDS, FCPS.
Asst. Professor Operative Dentistry
DIKIOHS,DOW University
Karachi

4. What is Nanotechnology

5. An emergent science formed from the convergence of
chemistry (classically restricted to atomic
interaction) and molecular scale physics and biology
(previously restricted to the micron scale)
Dental update Jan-Feb 2003

6. Nanofilled Composites
• Handling
• Easy finishing and polishing
• Durability

7. Preparation for Posterior
Composite Restorations

8. Centric occlusal stops located
primarily on tooth structure

9. Excessive tooth wear from
clenching or grinding

10. Esthetics as a prime
consideration

11. Cavosurface margins in enamel

12. Follow Directions For Use

13. Contamination
• Biofilm
• Gingival Exudate
• Saliva
• Blood
• Eugenol
• Handpiece Oil

14. No special Preparation for Class
1 Composite Restorations

15. Margins of the Occlusal Preparation
should not be Bevelled

16. Class 2 Composite Restorations

17. Prewedging

21. Beveling for facial and lingual
margins of the proximal box

24. Gingival Margins

25. Occlusal Margins
Placement of occlusal bevels has
demonstrated no benefit to the
longevity of class 2 resin
composite
restorations

28. Cavity Liners with Composite
Restorations

29. Calcium- Hydroxide Liner

30. Glass-ionomer Liners
• Improve marginal integrity and decrease marginal
leakage (J Dent 1993;21:158-162)
Reduce polymerization shrinkage and cuspal
deformation(Quintessence Int 1988;19:191-1980
• How should composite be layered to reduce
shrinkage stress: Incremental or bulk filling?
. (Dental Materials 2008 ; 24 :1501 – 1505)

31. Glass ionomer liners
• SEM and microleakage evaluation of the
marginal integrity of two types of class V
restorations with or without the use of a
light-curable coating
• J Dent. 2008 Nov;36(11):885-91. Epub 2008
Aug 30 material and of polishing.

32. Dental Composites are much stronger
than the liners and bases and are
equally insulating
JADA 1994;125:687-701
Investigation of the electrical
properties of some dental
composite restorative materials
before and after laser exposure
Dental materials 2005 ;vol 22 : 885
- 895

33. Use of glass ionomer liner on
dentine cavity surfaces has shown
to significantly reduce
postoperative sensitivity
Am J Dent 2001;14:34-38

36. Bonded Base Technique

38. Techniques to make tight contacts
• Use of thin sectional matrices
• Prewedging
• Prepolymerized composite balls
• Special wedge shaped composite curing tips.

43. Do you need to use flowable composite
under posterior composite restorations?

44. The Snow Plow Technique

45. Improvements in Dentine Bonding
Systems

46. The wet bonding technique has been
repeatedly shown to enhance bond
strengths
Quintessence Int 2001;32:385-390

47. Nanotechnology Dental
Adhesives

48. Incorporation of organic solvents like
acetone or ethanol

49. Dentine is air dried collagen fibres
collapse

52. Depending on cavity size,
dispense 1 or 2 drops of
XENO V into a DENTSPLY
CliXdish™.
Picture DFU

53. In a closed CliXdish XENO V
remains useable for up to
30 minutes. Disassemble
for cleaning and
disinfection.
Picture DFU

54. Apply XENO V twice,
wetting all cavity surfaces
uniformly with each
application.
Picture DFU

55. Then gently agitate the
adhesive for 20 seconds.
Picture DFU

56. Evaporate solvent by
thoroughly blowing with
air for at least 5 sec.
Avoid pooling.
Picture DFU

57. Cure for at least 20 seconds.
Min. Output Halogen ≥ 500
mW/cm2
Min. Output LED ≥ 800
mW/cm2
Picture DFU

58. Place increments
Picture DFU

59. INCREMENTAL TECHNIQUE

60. • Shrinkage results in interfacial stresses, with the
potential for debonding and/or local fracture of
tissue or restorative.
• Shrinkage should be minimised as far as possible.
Shrinkage

61. Light-cure each increment
(4 mm)
Picture DFU
* 10 sec for light output ≥ 800 mW/cm2,
20 sec for light output of 500 to 800 mW/cm2.

62. Polishing can be done
immediately
Picture DFU

63. Clinical Case

64. Clinical Case

65. Core Buildup (Pre-Op)

66. Core Buildup (Post-Op)

67. Wear Resistance
• Clinical Relevance: A low wear rate means that
enamel-restorative margins and contact points
remain at the correct level, and that gross loss of
material does not occur. It goes without saying that a
low wear rate is a prerequisite for a modern
composite.

68. Flexural Strength and Modulus
Clinical Relevance: The flexural strength of a
dental material is an important property since
materials may be used in thin layers or in
poorly supported edges where flexural forces
occur.
A high flexural strength is therefore needed.