LASERS IN ORTHODONTICS GUIDE SMT DR CHANDRALEKHA PROFESSOR AND HEAD OF DEPARTMENTDEPARTMENT OF ORTHODONTICSVYDEHI INSTITUTE OF DENTAL SCIENCES

PRESENTED BY DR OMAR RIZVI POST GRADUATE STUDENT DEPARTMENT OF ORTHODONTICS VYDEHI INSTITUTE OF DENTAL SCIENCES

SPECIAL THANKS TO SHRI DR VENKETESHIAH PROFESSOR OF DEPARTMENT OF ORTHODONTICS SMT DR ROOPA SR LECTURER DEPARTMENT OF ORTHODONTICS

SHRI DR VINOD SR LECTURER DEPARTMENT OF ORTHODONTICS

L light A amplified by S stimulated E emission of R radiation

LASER is a device that transforms a light of various frequencies into chromatic radiation in the visible, infrared and ultraviolet regions, with all the waves in phase capable of mobilizing immense heat and power when focused at a close range

Historical perspectiveEarly 1900s-chinese and egyptians (phototherapy)1960 Thiodore Maiman1965 Dr Goldman1970s nd-YAG1982- Pick Frame and Picaro1987 Meyers portable laser

Stern and sognnaes(1964) and Goldman et al (1964) were the first to investigate potential uses of ruby lasers in dentistry They began their studies on dental hard tissue by investigating the possible use of a ruby laser to reduce surface dimeralisation.

HISTORY1991 Soft Laser1993 Nd:YAG Laser1993 Kinetic Cavity Preparation1994 CO2 Laser, Argon Laser1996 Laser welder1997 Nd:YAP Laser1998 Er:YAG Laser

FUNDAMENTALS OF LASERS

Light beam is composed of packets of energy known as photons Ground state-atoms are normal stateAtoms are excited by energy and move to higher energyAs it reverts back to its ground state, energy is emitted-spontaneous emissionResults without external interference and forms waves that are in phase.With all the various types of lights and materials on the market, it is virtually impossible to come up with one protocol, especially one featuring reduced curing times,across the board.

Curing Lights

Curing lights allow us to polymerize on demand a vast array of materials.If you undercure a restoration, for example, you may not even be aware of the negative sequelae for years. Using a light that puts out too much energy also continues to be a topic for discussion. Therefore,selecting a curing light and using it properly can greatly affect the performance and longevity of your restorations.

Types of Curing Lights

Halogen Use a halogen bulb as the source of light.+ Most common+ Least expensive+ Reliable+ Long track record+ Should cure all materials + Available in corded and cordless models+ Wide bandwidth (400nm-510nm) Somewhat slower than plasma arc and argon lasers

Plasma Arc Bulb is really an aluminum oxide, high pressure vessel, which contains highly energized xenon gas (plasma) under 150psi. The inside shape is specific to reflect light arcing between two electrodes. Arc is only about 1mm long, enabling a very focused beam.+ Very fast

Expensive

Larger than halogen

Limited track record

May not cure all materials

Tips are usually too small for most restorations

Cords are liquid-filled, may be stiff, and can degenerate over time

Argon Laser Light generated when energy is applied to an atom raising an electron to a higher, unstable energy level. Electron will return to stable level by releasing lightthrough a medium of argon gas.+ Fast Tips are usually too small for most restorations Very expensive Larger than halogen May not cure all materials

LED (Light Emitting Diode) Special diodes (an electronic device that restricts current flow chiefly to one direction) that emit light when connected in a circuit.+ Available in cordless and corded+ Light in weight+ Small+ Long battery life due to the low power usage+ Virtually no heat generation at the tip New, very limited track record May not cure all materials Most have poor selection of tips Power output questionable

Curing Modes

High or Boost Usually the highest power the light will generate.Achieves this power within five seconds of activation.Entire curing interval will be at this level power. Typicallysynchronized to a timer that has a 10-second curing interval,which may not be adequate for many restorations.

Regular or Normal Medium power level.Will usually cureall types of restorations just a little slower than high power.

Step Cure at low power (usually about 150mW/cm2) for 10seconds, followed by an instant step up to a much higherpower (usually maximum of light) for the rest of the curinginterval.

Ramp Start curing at low power (usually about150mW/cm2), followed by a linear increase to a higherpower (usually maximum of light) for 10 seconds, and then stay at that high level for the rest of the curing interval.

Pulse Has different meanings for different lights, but usually means either the power cycles between high and low every second or so or the power cycles on and off every second or so from the beginning of curing.

Nd: YAG laser

DIAODE LASERSEMICONDUCTOR LASER

Gallium Arsenide chipNo mirror to clean and alignNo gas tube, flashlamps, laser rod, water coolingPortableNo special powerNo cooling connectionNo heat QuietAffordableMore powerful, less traumatic250microsecond-10sec0.05 Hz - 200 HzExpand Practice* Sulcular debridement* Root canal treatment

Caries RemovalCavity PreparationHard tissue modificationSoft tissue modificationPeak absorption of water andHydroxyapatiteVaporize the water rapidlyAcusto-mechanical wave

What is orthodontics???

Branch of dentistry concerned with prevention, interception and correction of malocclusion and other abnormalities of the dento facial region.

Here is why pateints come commonly to a orthodontist.

The result we achieve by our treatment.

Future Trends in Dentistry No pain Smile

WHY ORTHDONTIC TREATEMENT ???

No pain?Pain

Vibration

Sound

Smile?Esthetic needsNon invasive

Incision, Excison, Vaporization, Ablation, HemostasisDecontamination, Aphtous Ulcer Tx, Drain AbscessOpeculectomy, Surgical uncovering, Enamel exposure Root canal treatment

LASERS..WHY SHOULD I??PRECISIONPOWERPERFORMANCETIME ANTI CARIOGENIC PREVENTS DECALCIFICATION

Why Etching in orthodontics???The primary effect of enamel etching is to increase the surface area and thereby change the surface from a low energy hydrophobic surface to high-energy hydrophilic surface ( Reynolds, 1975 ).

Various surface properties may be accomplished but the most important point is to modify the surface characteristic of the enamel for adhesive attachment ( Silverstone et al. , 1975 ).

Various preparation methods including orthophosphoric acid, sandblasting, and laser irradiation have been shown to etch enamel for orthodontic bonding

Acid etching decalcifies the inorganic component of the enamel and the enamel becomes more susceptible to carious attack, which is induced by plaque accumulation around the bonded orthodontic attachments.

Laser irradiation removes the smear layer. After laser etching, some physical changes occur, such as melting and recrystallization. Numerous pores and bubble-like inclusions appear Thus, irregular surfaces are created which permit penetration of fluid adhesive components. The main disadvantage was the immediate increase in temperature, resulting in an inflammatory pulpal responseThe main advantage of the laser-etched surface is acid resistance. It yields more resistant enamel for caries attack

Reason ????The purpose of my thesis work is to investigate the shear peel bond strength and adhesive failure location of laser- and sandblasted-etched enamel compared with conventional acid-etching techniques, and to determine the suitability of these modalities in bonding of brackets

WHY DID I CHOOSE LASERS??

This is where I want to reach Treatment should be available to every one irrespective what our economic statusHow do we do this RESEARCH is the key .

What role do researchers play ???Well its the researchers contribution that today numerous dental procedures are affordable by the masses.Different studies carried out over the years have gifted dentistry with introduction of lasers

FrenectomyGingival troughing

Minimal marginal gingival regeneration: A, placement of topical anesthetic on a previously impacted canine with short clinical crown height;B, gingivectomy performed with an Er,Cr:YSGG, Waterlase; strict hemostasis with an erbium laser may be difficult; C, gingivectomy complete and tissue tag removed (photo taken immediately postoperatively); D, 3-month postsurgical follow-up with minimal marginal gingival regeneration.

Application of low level of laser

Gingival Recontouring

Gingivoplasty

EXPLORE NEW VISTAS, LET LASER TRANSFER YOUR PRACTICE

KEEP SMILING. THANK YOU..