New Advances in
Dr Wael Al-Omari
BDS, MDentSci, PhD
Drawbacks of Conventional Methods:
Contamination and cross-infection
The need for presterilisation cleaning.
1-Manual cleaning of burs
3-Ulrasonic cleaners with enzymatic detergents
Removal of infected and unaffected tissues.
- Is total caries removal necessary?
Noise, vibration and discomfort experienced with
Rational behind New Developments
Removal of only infected dentin
Reduce patients anxiety
Provide favorable surface features for bonding
Reduce contamination and cross-infection
Reduce the need for anesthesia
Easier recognition between infected and
Provide equal or superior efficiency compared
to conventional methods
New Developments in Caries Removal
Air Abrasion (Kinetic Cavity Preparation)
Atraumatic Restorative Treatment.
Early Lasers (Caron dioxide, ruby and
1- Inefficient cutting
2- Excessive heat generation
3- More efficient for soft tissue surgery.
Nd:YAG laser ablated dentin showing
craters and cracks and heat induced
band (Lin et al, 2001)
Erbium yttrium aluminum garnet
(Er:YAG, 2.94 µm wavelength)
Erbium chromium yttrium scandium
gallium garnet (Er,Ch:YSGG, 2.78
Mechanism of ablation by erbium lasers
- High absorption coefficient in water and high
affinity for hydroxyapatite.
- Absorbed heat cause microexplosions and
microfragmentataion of target issue.
- Irradiated surface demonstrate
microirregularities, absence of smear layer,
open tubules, absence of extensive thermal
Cavity prepared with erbium laser
Bur cut versus Er,ch:YSGG laser cut dentin
(Ekworapoj et al, 2007)
Advantages of erbium lasers
No thermal effect on target tissues and
Noiseless, no vibrations.
No harmful effect on the pulp.
Distinguishing between infected and
uninfected dentine might be possible.
Various clinical applications:
periodontics, endodontics, operative
Disadvantages of erbium lasers
Erbium laser preparations must be
followed by acid etching for reliable
bonding to resin composite
May weaken the irradiated surface
Defocusing effect due to water spray
Tissues can be only removed when it is
visible to operator’s line of sight.
Lack of tactile sensation
Waterlase MD Biolase ezlase 940
New more efficient generations of
Lasers with femtosecond pulse
duration (pulse duration = 10-15 s)
(Kinetic Cavity Preparation)
This technique uses a pressurized
stream of small aluminum oxide
particles to abrade carious lesion.
Typical Air Abrasion system:
- Particle diameter 27-50 µm.
- Powder flow rate 0.7-4.2 g/min
- Air pressure 40-160 psi
- Operating distance from tooth 0.5-2 mm
Air Abrasion Unit
Removal of superficial enamel defects
For detection pit and fissure caries by removal of
Removal of enamel surface stains.
Removal of localized minimal carious lesion
Surface preparation of abfractions and abrasions
to brake the glaze of the surface for better
Removal of existing restorations.
The need for anesthesia may be avoided
because of the cooling effect of the high
Cavity prepared using air abrasion technique
Advantages of Air Abrasion
Less painful than bur preparation
due to less noise and vibration.
More conservative than bur for
minimal fissure and pit caries.
Roughened surfaces may favor
better bonding….However air
abrasion is not a substitute for acid
Limitations of Air Abrasion
There is little tactile sensation
Unable to remove gross caries.
Removes normal and relatively hard dentin.
Remove exposed cementum and root
Splattering f powder-risk of ingestion.
Unable to prepare well-defined cavity
Does not obviate the need for acid etching.
May lacerate soft tissues
Removal of large amalgam causes release
Mandatory need for rubber dam, high
velocity evacuation and protective eyewear
Future Developments in Air Abrasion
Less abrasive powders
- Softer particles may be more
effective in selective removal of
Described by Boston (2000).
Made of a softer polyamide/imide polymer
Remove infected dentine only
Manufacturer: SmartPrep (SS White, USA)
Harder than carious dentine and softer than
Designed for single use on slow-handpiece
Remove caries from central of lesion to
Less effective than carbide bur in caries
removal (Dammaschke et al, 2006)
Polymer burs SmartPrep before (1a) and after
(1b) use (Dammaschke et al, 2006)
Fissurotomy Burs (SS White,USA) allow
exploration of the fissures with minimal
removal of enamel.
It is 1.5-2.5 mm in length and tapers to
fine carbide tip.
Other burs such as Brassler 889M-007 bur
and Microdiamond 838M-007 burs are
used for minimal preparation.
Microinstruments (Micropreparation set)
requires low contact pressure (< 2N)
Conventional bur versus fissurotomy bur
The system use disinfectant solution
applied to deep caries, allowed to
penetrate softened dentin for 60 s, and
then photoactivated with low-powered
diode laser for 1 min.
Dilute toluidine blue binds to bacteria.
Red light activation release oxygen that
kills the cells
Healthy tissues are not damaged by
Toluidine blue is safe at the used
Toludine blue and laser acts together
Photo-Activated Disinfection (PAD)
Carisolv s a chemomechanical method
for caries removal.
It is a mixture of amino acids and 05%
The resultant high-pH chloramines
reacts with denatured collagen in
Softened dentin is removed with
special hand instruments
Special hand instruments used with Carisolv Gel
Clinical Indications For Carisolv Gel
Removal of root and coronal caries
where access is easily obtained
Due to selective removal of carious
dentine, the need foe anesthesia is
reduced , thus the technique is
indicated in children, dental-phobic
patients and special needs patients
Advantages of Carisolve Gel
Selective removal of carious dentine.
The reduced need for anesthesia
Does not affect the bonding to
Removes smear layer
Does not cause adverse effect on the
Disadvantages of Carisolv Gel
Technique requires longer time than
May be inefficient for removing
caries at enamel-dentin junction.
Caries under overhanging enamel
may go unnoticed.
Large lesions needs to be accessed
using rotary bur.
Atraumatic Restorative Treatment ِ
Atraumatic Restorative Treatment is
a procedure based on removing
carious tooth tissue sing hand
instruments alone and restoring the
cavity with an adhesive restorative
material namely glass ionomer
Hand instruments used in ART
Reasons for using hand instruments in ART
Makes restorative procedure
accessible to all population.
Minimal cavity preparation
Reduce need for anesthesia
Simplified infection control due to
easy cleaning and sterilization
Reason for using glass-ionomer in ART
Glass ionomer sticks chemically to
enamel and dentin
Compatible to oral and hard dental
Advantages of ART
Benefit the less-industrialized and
Minimal invasion preparations
Friendly procedure for children,
fearful adults, physically or mentally
handicapped, people living in
nursing homes and the home-bound
Disadvantages of ART
Restorations tend to fail and wear.
Incomplete removal of bacteria
Wear and failure means that
patients require frequent review by
Difficult o remove caries in
Caries Detection Dyes
Dyes such as 1.0% acid red in propylene
They stain infected dentine and organic
matrix of demineralised of carious dentin
that should not be removed.
They stain dentin naturally with low minerals
such as circumpulpal dentin and enamel-
Result in overpreparations.
Not useful in detecting pt and fissure caries
because they stain food debris and other
organic materials in the fissure
They are not recommended
Caries detecting dyes stains demineralised
matrix of carious dentin that should not be