REMINERALIZING AGENTS

SONO-ABRASION 2

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

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

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.

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 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.

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

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:

• 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

CVD DIAMOND BURS 2

[

MANUFACTURING

These tips, called CVD, are produced in a reactor in which a mixture of methane and hydrogen gases results in the formation of a single artificial diamond layer without space between the grains on the substrate (a molybdenum rod)

WORKING PRINCIPLE

CVD diamonds burs present unidirectional oscillating movement with maximal displacement ranging from 50 to 60 micron,at oscillating frequencies ranging from 25,000 to 32,000 Hz.

CVD diamond tip require only a slight touch to promote tooth grinding

This differs from the high speed handpiece, which is manipulated with pendulum movements over tooth structure.

Movement with maximal displacement ranging from 50 to 60 micron,at oscillating frequencies ranging from 25,000 to 32,000 Hz.


CVD diamond burs must be handled with light hand pressure,just enough to guide the instrument.

If too much load pressure is applied,the cutting effectiveness is reduced and pain,noise,and heat will be generated.

A greater application force reduces the cutting ability of the tip and may lead to fracture of the molybdenum substrate.

In addition the lack of irrigation of the ultrasound instrument on the treated surface may cause the tip to heat up and fracture.

This system doesn’t lose superficial diamond during cutting,subsequently extending the lifetime.

CVD feature significantly decrease the risk of metal contamination

CVD instrument allows the capability of working at high inclination angles,resulting in safer proximal finishing with less chance of hitting adjacent tooth.

CHEMICAL VAPOUR DEPOSITION(CVD) DIAMOND BURS

CHEMICAL VAPOUR DEPOSITION(CVD) DIAMOND BURS

CVD technology allows high adherence of the diamond as a unique stone on the metallic surface with excellent abrading performance.

CVD diamond burs become an option for cavity preparation,and preservation of tooth structure.

In 1996,CVD diamond burs coupled with an ultrasonic handpiece were introduced in dentistry to eliminate problems relate with diamond burs

CVD method produce high adherence between the diamond film and metal surface,induced by chemical bond

Because of the inherent roughness of the sharp edged and polycrystalline diamond layers,these tools are well suited for tooth grinding










They are obtained by chemical vapour deposition( CVD) of diamond film over a molybdenum substrate.

They were synthesized inside an enhanced hot filament assisted reactor.

This manufacturing process,and the adaptation to an ultrasonic handpiece,provide some potential advantage.

SMART BUR 2

PROCEDURE









WITHOUT LA

SMART BUR Cutting is limited to the superficial layer of affected dentin will not remove the odontoblast reaction zone of mineralized tubule plugs and can be completed without the use of LA

When working with the polymer(SMART) bur, and early intensive contact with hard areas of the tooth should be avoided to reduce the possibility that the excavating performance of the bur is diminished.

Like conventional bur,polymer(SMART) bur rake angle is also negative.unlike cabide bur,the downward pressure applied by the polymer bur against the tissue is dessipated as the bur starts abrade when it encounters hard dentine

The dentist was requested to exert as little force as possible on the SMART BUR.

CONSERVATIVE

One of the goals of conservative dentistry is to develop a method of removing caries-infected dentin while preserving caries-affected dentin.

The polymer(SMART BUR) instrument appears to offer a
straightforward and efficient means of achieving this goal and conserving healthy tooth

SMARTPREP (SMART BUR) INSTRUMENTS

POLYMER BUR or SMART BUR

The SMARTPREP Instrument is a medical grade polymer that safely and effectively remove decayed dentin, leaving healthy dentin intact.

The hardness of instrument is less than that of healthy dentin and enamel but harder than carious dentin

SELFLIMITING

The polymer instrument is self-limiting and will not cut sound dentin unless applied with great force, and then it will only wear away, rather than cut, the healthy dentin

Smartprep instrument in a range of sizes (equivalent to round burs nos. 2, 4 and 6)

The Smartprep Instrument is used in a slow speed handpiece (500-800 rpm) to complete caries removal

They are single-patient-use rotary instruments

Carious tissue is removed with circular movements starting from the centre to the periphery.

ADVANTAGE

They are being used for deep caries removal in anticipation of an indirect pulp capping procedure

Use the Smart-Prep burs in the beginning of their clinic experience and hopefully a

void iatrogenic pulp exposures

DISADVANTAGE

Polymer bur left large amount of decayed tissue unexcavated (underprepation)

Technique sensitive (the Smart Prep can be readily defeated by the dumb operator)

the burs disintegrate when they touch enamel or even sound dentin

potentially expensive

BURNISHERS

BURNISHERS

To burnish amalgam restoration.
for making occlusal anatomy of composite restoration
for marginal adaptation of gold

TYPES

• PK Thomas no. 3(cone) burnisher
• Beavertail burnisher no. 2
• Foot ball or ovoid no.30 burnisher
• Sprateley burnisher
• Anatomic burnisher

ANATOMIC BURNISHER
They are used for sculpturing occlusal anatomy in posterior resin composite restoration prior to polymerisation.

BEAVERTAIL
Closing of marginal gap between gold and tooth in cast gold restoration



SPRATELEY
For burnishing proximal gingival margin metallic restoration

TYPES OF CARVER

They are used for carving amalgam and resin composites

TYPES

Large discoid - cleoid

Small discoid - cleoid

No.14 sickel shaped carver

Hollenback no. ½ caver

Frahms 90 degree carver

Walls no.3

Interproximal carver

Wards carver

Scalpel blade no. 12 mounted on scalpel handle

• Cleoid-discoid - for carving occlusal surface in molar and useful for lingual concavities in anterior teeth

• Walls no.3 – for carving occlusal surface,the end that is shaped like hoe is used for shaping cusps & for carving lingual and facial surfaces

• Hollenback – used for occlusal,proximal,axial surfaces
  

• Interproxiaml – have very thin blades for carving proximal amalgam surface

• Scalpel blade No. 12 - is used for carving resin composite restorations

• Sickel No.14L – For carving interproximal areas.It has very strong hollow round triangular blade – to remove amalgam over hangs.
  

• Wards carver - for occlusal surface and carving proximal surface in class IIrestoration.

• Frahm's 90 degree carver(diamond carver) - for carving occlusal surface.

FLUORIDE RELEASE AND RECHARGE OF DIFFERENT MATERIALS

GLASS IONOMER

The releasing and recharge ability of the material fully depends on the glass particle,particularly the amount of hydrogel layer over glass filler.

In case of glass ionomer the powder liquid reaction is acid base reaction and the reaction results in more well defined amount of hydrogel matrix over the glass particle.

So that glass ionomer release large amount of fluoride initially(hydrogel matrix) and release reduces with time, at the same time the released fluoride is recharged with exernal fluoride source such as fluoride solution,fluoride varnish,fluoride tooth paste.fluoride mouthrinse.

The initial "burst" effect is only seen in glass ionomer,compomer and giomer does on exibit initial "burst".


COMPOMER
In Compomer, polyacrylic acid and resin matrix combined into one molecule.

Initially polymerization reaction takes place followed by subsequent sorption of water leads to ionization of acid and acid base reaction takes place at the slow rate.The fluoride release is during first sevan days in expected to be low.

The acid base reaction is less prominent in this case and hydrogel layer formed in small part.

In Compomer fluoride release is less when compared to glass ionomer and the recharging ability is not seen case of compomer.

GIOMER
In Giomer the fluoride release is similar to that of glass ionomer,the difference of giomer from compomer in fluoride release is both contain glass ionomer and resin matrix but in case of giomer the glass particles are pre-reacted with polyacrylic acid before blending with resin matrix.

The hydrogel layer is more extensive in giomer similar to that of glass ionomer.

Fluoride release in case of giomer is by exchange mechanism in the direction of lower fluoride concentration from higher concentration.The existence of a CONCENTRATION GRADIENT is the driving force for fluoride release.

Fluoride release of giomer was greaer than other materials at day sevan and it became significantly lower at day due to diminishing fluoride gradient

REFERENCES
Giomer restorations,Dental Abstracts
Volume 50, Issue 6, November-December 2005, Page 355

A three-year clinical evaluation of two dentin bonding agents
J Am Dent Assoc, Vol 135, No 4, 451-457
BRUCE A. MATIS, D.D.S., M.S.D., MICHAEL J. COCHRAN, D.D.S., M.S.D.,

Evaluation of a self-etching primer and a giomer restorative material: Results at eight years
J Am Dent Assoc 2007;138;621-627
Valeria V. Gordan, Eduardo Mondragon, Ronald

Surface Finish of a New Hybrid Aesthetic Restorative Material
Operative Dentistry, 2002, 27, 161-166
AUJ Yap • BYY Mok

Short-Term Fluoride Release from Various Aesthetic Restorative Materials
Operative Dentistry, 2002, 27, 259-265,AUJ Yap • SY Tham,LY Zhu • HK Lee

Fluoride release and recharge in giomer,compomer and resin composite
Dental Materials (2004) 20, 789–795
Toshiyuki Itotaa,b, Thomas E. Carricka, Masahiro Yoshiyamab,John F. McCabea

Clinical evaluation of two one-bottle dentin adhesives at three years ,
J Am Dent Assoc, Vol 132, No 8, 1117-1123
EDWARD J. SWIFT JR., D.M.D., M.S., JORGE PERDIGÃO, D.D.S., M.S., PH.D.,

GIOMER

GIOMER is basically a modified GLASS IONOMER.

It is a true hybrid of two compounds, Glass Ionomer and Composite

The difference of Giomer from Compomer is, in Compomer variable amount of unhydrated polyacrylic acid is added to the resin matrix and the acid base reaction wont takes place until water comes and contact with compomer

The main disadvantage of COMPOMER is less amount of Fluoride release and absence of Fluoride recharging ability.This makes the GIOMER more preferable then compomer

GIOMER uses PRG( Pre Reacted Glass ionomer ) TECHNOLOGY by which it differs from compomer, in giomer the glass filler particles used are pre reacted with polyacrylic acid

By using this technology,we can get the properties of both glass ionomer and composites.

The properties of GIOMER is fluoride release and fluoride recharging of glass ionomer and esthetics,easy of polishing,and strength of composite.

COMPOSITION Of GIOMER (BEAUTIFUL)

• Bisphenol A glycidyl dimethacrylate,
• TEGDMA,
• inorganic glass filler,
• aluminuoxide, silica,
• pre-reacted glass ionomer filler,
• DL-camphorquinone

PRG TECHNOLOGY IN GIOMER

There is a pre reaction of Fluoroalumino silicate glass fillers with Polyacrylic acid,the reaction produce a glass ionomer which is more stable

This phase is called”WET SILICEOUS HYDROGEL”

This material is freeze dried, milled, treated with silane and then round to produce PRG fillers, then these glass fillers are added to the resin matrix(GIOMER)

PRG TECHNOLOGY is used in production of two types of fillers.

They are:
S-PRG (Surface Pre Reacted Glass Ionomer) marketed as BEAUTIFUL (shofu)

F-PRG (Full Pre Reacted Glass Ionomer) marketed as REACTMER (shofu)

GOD'S GRACE