TIP MOTION
The tips describe an elliptical motion with a trans verse distance of between 0.08 – 0.15 mm and a longitudinal movement of between 0.055 – 0.135 mm.Diamond coated on one side using 40 μm grit diamond and are cooled using water irrigant at a flow rate of between 20–30 mL /min.
Considering the semi-rotary movement of the tip, the very high frequency of oscillations of the tip and the subsequently produced heat, dentin exposed by sono-abrasion can also be assumed to be covered by a smear layer.
LIMITATION
The torque applied to the instrument tips should be in the region of 2 N.
If the applied pressure is too great, the cutting efficiency is reduced due to damping of the oscillations
STUDIES
Van Meerbeek et al found that sono-abrasion resulted in enamel and dentin surfaces equally receptive towards bonding as compared with bur-cut surfaces, they also found that a three-step etch-and-rinse adhesive (Optibond) with omission of the acid-conditioning phase obtains higher bond strengths when bonded to sono-abraded dentin than to bur-cut dentin.
This was explained by the relatively high acidity of the primer of Optibond FI. (pH= 1.78), which thus acts as a self-etch adhesive, and by the fact that sono-abrasion presumably produces rather thin smear layers.
Pioch et al. investigated the interface of an etch-and-rinse adhesive with confocal laser scanning microscopy and did not see any difference between bur-prepared or sono-abraded dentin of primary teeth.
Opdam et al.| reported equal microleakage in class-II cavities prepared by bur or SonicSys, respectively. Their study was confirmed by the findings of Setien [57].
Minimally Invasive Technique
Sono-abrasion should be regarded as a good complement to rotary instruments for cavity preparation, the main advantages being less damage to adjacent teeth and minimally invasive cavities. A sono-abraded dentin surface is also covered by a thin smear layer.
Dentine caries excavation: a review of
current clinical techniques
Banerjee,1 T. F. Watson,2 and E. A. M. Kidd,3
BRITISH DENTAL JOURNAL VOLUME 188. NO.9 MAY 13 2000 476-482
Thursday, October 16, 2008
Saturday, October 11, 2008
SONO-ABRASION
SONO-ABRASION
INTRODUCTION
A recent development from the original ultrasonics ,is the use of
high-frequency, sonic, air-scalers with modified abrasive tips – a technique known
as ‘sono-abrasion’
The Sonicsys micro unit, designed by Drs Hugo, Unterbrink and
Mösele
Sono-abrasion is based upon the Sonicflex 2000L and 2000N air-scaler handpieces that oscillate in the sonic region (< 6.5 kHz)
WORKING PRINCIPLE
Sono abrasion technique is based on the removal of tooth material by an air-driven hand piece equipped with a diamond-coated working tip that removes tooth material by ultrasonic kinetic energy.
sono-abrasion has been introduced as an alternative for preparing minimally invasive cavities .
Sono abrasion technique was initially developed to prepare predetermined cavity outlines but also works well in removing hard tissue when finishing cavity preparation.
DIAMOND TIPS
Different sizes and shapes of diamond tips have been designed.
There are three different instrument tips:
lengthways halved torpedo shape (9.5 mm long, 1.3 mm wide),
small hemisphere (1.5 mm diameter) and
large hemisphere(2.2 mm).
As these tips are coated only on one side, additional damage and trauma of the approximal side of adjacent teeth is prevented.
The constricted shape of the tip enables easy access in small occlusal and approximal cavities.
Sono-abrasion can be used for beveling the cavity margins, thereby improving the marginal adaptation of a composite filling
INTRODUCTION
A recent development from the original ultrasonics ,is the use of
high-frequency, sonic, air-scalers with modified abrasive tips – a technique known
as ‘sono-abrasion’
The Sonicsys micro unit, designed by Drs Hugo, Unterbrink and
Mösele
Sono-abrasion is based upon the Sonicflex 2000L and 2000N air-scaler handpieces that oscillate in the sonic region (< 6.5 kHz)
WORKING PRINCIPLE
Sono abrasion technique is based on the removal of tooth material by an air-driven hand piece equipped with a diamond-coated working tip that removes tooth material by ultrasonic kinetic energy.
sono-abrasion has been introduced as an alternative for preparing minimally invasive cavities .
Sono abrasion technique was initially developed to prepare predetermined cavity outlines but also works well in removing hard tissue when finishing cavity preparation.
DIAMOND TIPS
Different sizes and shapes of diamond tips have been designed.
There are three different instrument tips:
lengthways halved torpedo shape (9.5 mm long, 1.3 mm wide),
small hemisphere (1.5 mm diameter) and
large hemisphere(2.2 mm).
As these tips are coated only on one side, additional damage and trauma of the approximal side of adjacent teeth is prevented.
The constricted shape of the tip enables easy access in small occlusal and approximal cavities.
Sono-abrasion can be used for beveling the cavity margins, thereby improving the marginal adaptation of a composite filling
Thursday, October 09, 2008
AIR ABRASION 4
PROTECTION DURING AIR ABRASION
Care should be taken to protect from aluminium oxide dust generated during Air abrasion procedure
INTRAORAL
High velocity vaccum shoulb be used.
Rubber dam or 2x2 or 4x4 size gauze laced in the throat .
EXTRAORAL
Safety glasses for dentist and patient while doing Air abrasion procedure.
Shield for dentist.
Adviced to cover sensitive equiments like camera and computer.
Particles less than 10 micron can penetrate the lung alveolar tissue.
Large article can be a upper airway irritant.
PARALLEL WATER TECHNIQUE-RAINEY
In Air abrasion, Particles are guided through a stream of water,cutting is more efficient and reduce the scattering of dust.
Disposable rear surface mouth mirror are adviced to use bcoz particles bounced off the tooth can ruin the mouth mirror.
In class II preparations barrier(rubber dam or matrix) should be used to protect the adjacent tooth.
Wednesday, October 08, 2008
FISH AND ALCOHOL IN ALZHEIMER'S DISEASE AND DEMENTIA
Eat fish and drink alcohol
Omega-3 fatty acids(fish) and the moderate intake of alcohol reduce Alzheimer’s disease and dementia
Omega-3 Fatty Acids(fish).
omega-3 fatty acids found in certain fish oils may also benefit the brain.
The ingestion of omega-3 fatty acid docosahexaenoic acid (DHA) over several months will slow cognitive and function decline in persons with Alzheimer’s disease.
The patients, 50 years or older, will receive 2 g of DHA daily influence physical and biological markers of Alzheimer’s disease, mainly, brain atrophy and proteins in blood and spinal fluid.
Alcohol.
Research suggests that moderate drinking of alcohol may significantly retard the progression of dementia in persons with mild age-related cognitive decline in comparison to persons who do not drink.
Moderate drinking of alcohol- <0.5 oz of alcohol a day.
Higher intake showed no protective benefit.
The protective dose of alcohol was typically found in a 12-oz glass of regular beer, a 5-oz glass of wine, or a cocktail containing 1 oz of alcoholic spirits.
Reference-Dental Abstracts Volume 53 Issue 3 2008 130-131
AIR ABRASION 3
THE EFFICIENCY OF AIR ABRASION IS INFLUENCED BY
Air pressure
Particle size
Powder flow
Tip size
Tip angle
Tip distance from tooth
AIR PRESSURE
The air abrasive units are used with 20 to 120psi
Higher pressure increases the sensitivity when cutting is in dentine
Most adviceable pressure is 40 to 60psi (not going beyond 80 psi)
PARTICLE SIZE
The particle size used in Air abrasion are 27 - 27.5 micron
(27 micron - 3/4 the size of human hair)
Smaller particle cuts faster and smoother when propelled at high speed.
Smaller article 27-27.5 micron are used to cut teeth.
Large particle are heavier and need more velocity to move.
Large particle 50 micron are used to clean the provisional restoration and inside of crown.
POWDER FLOW
When pressure is reduced the flow will increase and its difficult to evacuate
TIP SIZE
It may be small or large
Small - 0.28mm(0.011 inch)
to
Large- 0.8mm(0.32inch)
TIP ANGLE
Tip is angulated 45 degree while doing Air abrasion procedure.
TIP DISTANCE
Kinetic energy decreases with increase in tip distance
Focused mode - 1-2 mm
Defocused mode - farther away
While using the Air abrasion device
It is adviced to give a short burst(3secs) instead of long spray
Then observe the Preparation and continue the Procedure
Air pressure
Particle size
Powder flow
Tip size
Tip angle
Tip distance from tooth
AIR PRESSURE
The air abrasive units are used with 20 to 120psi
Higher pressure increases the sensitivity when cutting is in dentine
Most adviceable pressure is 40 to 60psi (not going beyond 80 psi)
PARTICLE SIZE
The particle size used in Air abrasion are 27 - 27.5 micron
(27 micron - 3/4 the size of human hair)
Smaller particle cuts faster and smoother when propelled at high speed.
Smaller article 27-27.5 micron are used to cut teeth.
Large particle are heavier and need more velocity to move.
Large particle 50 micron are used to clean the provisional restoration and inside of crown.
POWDER FLOW
When pressure is reduced the flow will increase and its difficult to evacuate
TIP SIZE
It may be small or large
Small - 0.28mm(0.011 inch)
to
Large- 0.8mm(0.32inch)
TIP ANGLE
Tip is angulated 45 degree while doing Air abrasion procedure.
TIP DISTANCE
Kinetic energy decreases with increase in tip distance
Focused mode - 1-2 mm
Defocused mode - farther away
While using the Air abrasion device
It is adviced to give a short burst(3secs) instead of long spray
Then observe the Preparation and continue the Procedure
Tuesday, October 07, 2008
AIR ABRASION 2
AIR ABRASION
ADVANTAGE
Pain during tooth structure removal is eliminated or at least reduced.
No vibration occurs during Air abrasion procedure
The only noise produced by Air abrasion is a familiar vacuum cleaner sound.
Well-designed tips provide good control during the procedure.
Patients who are afraid of traditional dentist techniques and the noise of airrotor handpieces can be treated, without anesthesia, using air abrasion.
It adapts well to Class I, IV and V preparations.
It is an especially useful technique for children.
Used properly, air abrasion "explores" incipient carious lesions extremely well, often locating carious areas previously undetectable visually or by radiography.
DISADVANTAGE
Air abrasion technique is not familiar,period to accustom themselves so dentists require a learning to it.
Tooth preparations do not resemble traditional, precise, clearly identifiable outlines.
The practitioner's tactile perception during tooth structure removal is minimal.
At this time, only small tooth preparations can be accomplished with the Air abrasion technique.
Expertise is required to control it by proper direction of the Air abrasion handpiece tip, excellent suction and, potentially, by use of air filtration devices.
The practitioner's vision is sometimes obscured by debris while tooth structure is being removed.
Performing air abrasion on Class II and III areas requires more extensive learning than that required for using the technique on other tooth locations.
Old amalgam cannot be removed produce mercury dust.
It doesnot remove soft decay bcoz the particles are absorbed to remove the soft decay one should use slow hand piece with no.2 or no.4 round bur or sharp spoon
Crown preparations are not possible with Air abrasion .
Aluminum oxide debris accumulates everywhere.
ADVANTAGE
Pain during tooth structure removal is eliminated or at least reduced.
No vibration occurs during Air abrasion procedure
The only noise produced by Air abrasion is a familiar vacuum cleaner sound.
Well-designed tips provide good control during the procedure.
Patients who are afraid of traditional dentist techniques and the noise of airrotor handpieces can be treated, without anesthesia, using air abrasion.
It adapts well to Class I, IV and V preparations.
It is an especially useful technique for children.
Used properly, air abrasion "explores" incipient carious lesions extremely well, often locating carious areas previously undetectable visually or by radiography.
DISADVANTAGE
Air abrasion technique is not familiar,period to accustom themselves so dentists require a learning to it.
Tooth preparations do not resemble traditional, precise, clearly identifiable outlines.
The practitioner's tactile perception during tooth structure removal is minimal.
At this time, only small tooth preparations can be accomplished with the Air abrasion technique.
Expertise is required to control it by proper direction of the Air abrasion handpiece tip, excellent suction and, potentially, by use of air filtration devices.
The practitioner's vision is sometimes obscured by debris while tooth structure is being removed.
Performing air abrasion on Class II and III areas requires more extensive learning than that required for using the technique on other tooth locations.
Old amalgam cannot be removed produce mercury dust.
It doesnot remove soft decay bcoz the particles are absorbed to remove the soft decay one should use slow hand piece with no.2 or no.4 round bur or sharp spoon
Crown preparations are not possible with Air abrasion .
Aluminum oxide debris accumulates everywhere.
Monday, October 06, 2008
AIR ABRASION - MINIMALLY INVASIVE TECHNIQUE
AIR ABRASION
Air abrasion is introduced by Dr.Robert.B.Black.
It is a parallel stream of focused narrow beam of 27 micron size of aluminium oxide.
The particle move according to law of physics .
When directed towards tooth surface it abrade with out heat, vibration,and noise.
Air abrasion conserve the tooth structure and maintains the structural integrity of the tooth.
It requires moderate learning curve and one should feel confident in using it.
There is no tactile sensation because the Air abrasion hand piece doesnt touch the tooth,and the cutting article exit at the it.
It is a end cutting device incontrast to rotary it cuts laterally.
MODES OF USES
Air abrasion handpiece can used in Two modes
Focused and unfocused mode.
Focused mode - 1-2 mm away from the tooth structure,it cuts enamel and dentine.
Defocused mode - farther away,it cleans the surface,explores the caries.
LAW OS PHYSICS
ENERGY(E) = 1/2 MASS x VELOCITY
Kinetic energy can be increased by increasing mass and velocity.
kinetic energy decreases with increase in tip distance.
INDICATIONS
Children, unaccustomed to traditional rotary-instrument tooth cutting, can be introduced to Air abrasion dentistry without psychological trauma.
Patients who cannot have local anesthesia because of various health reasons can be treated using air-abrasion techniques.
Patients who are afraid of traditional dentistry techniques and the noise of airotor handpieces can be treated.
CONTRAINDICATIONS
Asthma
Dust allergy
Periodontal disease
Recent extraction sites
Air abrasion is introduced by Dr.Robert.B.Black.
It is a parallel stream of focused narrow beam of 27 micron size of aluminium oxide.
The particle move according to law of physics .
When directed towards tooth surface it abrade with out heat, vibration,and noise.
Air abrasion conserve the tooth structure and maintains the structural integrity of the tooth.
It requires moderate learning curve and one should feel confident in using it.
There is no tactile sensation because the Air abrasion hand piece doesnt touch the tooth,and the cutting article exit at the it.
It is a end cutting device incontrast to rotary it cuts laterally.
MODES OF USES
Air abrasion handpiece can used in Two modes
Focused and unfocused mode.
Focused mode - 1-2 mm away from the tooth structure,it cuts enamel and dentine.
Defocused mode - farther away,it cleans the surface,explores the caries.
LAW OS PHYSICS
ENERGY(E) = 1/2 MASS x VELOCITY
Kinetic energy can be increased by increasing mass and velocity.
kinetic energy decreases with increase in tip distance.
INDICATIONS
Children, unaccustomed to traditional rotary-instrument tooth cutting, can be introduced to Air abrasion dentistry without psychological trauma.
Patients who cannot have local anesthesia because of various health reasons can be treated using air-abrasion techniques.
Patients who are afraid of traditional dentistry techniques and the noise of airotor handpieces can be treated.
CONTRAINDICATIONS
Asthma
Dust allergy
Periodontal disease
Recent extraction sites
Sunday, October 05, 2008
CVD DIAMOND BURS 3
ADVANTAGE
Better Cooling: Cooling water flows over the entire CVD tip rod and reaches the extremity without interference with its trajectory
Less Noise: Noise occurs only when the CVDpoint comes into contact with tooth Structure
Greater Durability: As a result of the new manufacturing technology, the resistance of the CVD diamond to displacement is greater than traditional diamond tips
Better Access and Visibility: CVD tip rods are long which allows the complete working area to be seen. They are also angled to provide better access to inaccessible areas
Effective Cavity Cleaning:
Preservation of tooth structure
Minimal damage to gingival tissue
Improved proximal access
Reduced risk of metal contamination
DISADVANTAGE
The cost of the CVD equipment must be considered for it is approximately 30 times more expensive than a conventional tip.
PROCEDURE
Better Cooling: Cooling water flows over the entire CVD tip rod and reaches the extremity without interference with its trajectory
Less Noise: Noise occurs only when the CVDpoint comes into contact with tooth Structure
Greater Durability: As a result of the new manufacturing technology, the resistance of the CVD diamond to displacement is greater than traditional diamond tips
Better Access and Visibility: CVD tip rods are long which allows the complete working area to be seen. They are also angled to provide better access to inaccessible areas
Effective Cavity Cleaning:
- Ultrasound produces a phenomenon called ultrasonic cavitation.
- Ultrasonic action forms air bubbles in a liquid medium.
- Many of these bubbles rise to the surface while others grow and implode, releasing a large amount of energy.
- This energy liberated on implosion causes intense movement of particles and cleaning of surfaces. This is the phenomenon which facilitates the cleaning of the surface of CVDdiamond instruments within the ultrasonic environment.
Preservation of tooth structure
Minimal damage to gingival tissue
Improved proximal access
Reduced risk of metal contamination
DISADVANTAGE
The cost of the CVD equipment must be considered for it is approximately 30 times more expensive than a conventional tip.
PROCEDURE
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