Uploaded bySanchiRonDutta
PPTX, PDF1,041 views

Laser

The document discusses the application and advancements of lasers in oral surgery and prosthodontics, detailing their historical development, physical principles, and various types of lasers used in dental practices. It highlights the benefits of lasers in enhancing patient care, including minimizing pain, reducing bacterial presence, and facilitating surgical procedures. The document also emphasizes laser classification, operational parameters, and specific applications in managing soft and hard tissues in dentistry.

Embed presentation

Downloaded 10 times
1 / 105
2 / 105
3 / 105
4 / 105
5 / 105
6 / 105
7 / 105
8 / 105
9 / 105
10 / 105
11 / 105
12 / 105
13 / 105
14 / 105
15 / 105
16 / 105
17 / 105
Most read
18 / 105
Most read
19 / 105
20 / 105
21 / 105
22 / 105
23 / 105
24 / 105
Most read
25 / 105
26 / 105
27 / 105
28 / 105
29 / 105
30 / 105
31 / 105
32 / 105
33 / 105
34 / 105
35 / 105
36 / 105
37 / 105
38 / 105
39 / 105
40 / 105
41 / 105
42 / 105
43 / 105
44 / 105
45 / 105
46 / 105
47 / 105
48 / 105
49 / 105
50 / 105
51 / 105
52 / 105
53 / 105
54 / 105
55 / 105
56 / 105
57 / 105
58 / 105
59 / 105
60 / 105
61 / 105
62 / 105
63 / 105
64 / 105
65 / 105
66 / 105
67 / 105
68 / 105
69 / 105
70 / 105
71 / 105
72 / 105
73 / 105
74 / 105
75 / 105
76 / 105
77 / 105
78 / 105
79 / 105
80 / 105
81 / 105
82 / 105
83 / 105
84 / 105
85 / 105
86 / 105
87 / 105
88 / 105
89 / 105
90 / 105
91 / 105
92 / 105
93 / 105
94 / 105
95 / 105
96 / 105
97 / 105
98 / 105
99 / 105
100 / 105
101 / 105
102 / 105
103 / 105
104 / 105
105 / 105
LASERSINORALSURGERYANDPROSTHODONTICS Dr. SANCHAYITA ROY & Dr. RON DUTTA
• INTRODUCTION • HISTORY • LASER PHYSICS • LASER COMPARTMENT AND DELIVERY SYSTEM • LASERCLASSIFICATION • LASER EFFECTS ON TISSUE • MOST COMMON LASERS IN DENTISTRY • LASER APPLICATION IN PROSTHODONTICS • LASERS IN RPD, CD, FPD, ESTHETICS, IMPLANT, MAXILLOFACIAL PROSTHESIS, DENTAL MATERIALS, USE IN LABORATORY • LASER IN ORAL SURGERY • LASER IN DIAGNOSIS • DENTAL LASERS IN FUTURE • LASER SAFETY • REFERENCES CONTENTS
INTRODUCTION • LASER = “light amplification by stimulated emission of radiation” • Lasers are devices that produce beams of coherent and very high intensity light. • An alternative to traditional halogen curing light, laser now has become the instrument of choice, in many dental applications. • Its advancements in the field of dentistry are playing a major role in patient care and well being
HISTORY ALBERT EINSTEIN 1915, Neils Bohr’s atomic model -- basis for quantum mechanics and, useful in demonstrating laser principles Einstein credited with development of Laser theory. Coin the term “Stimulated Emission” in his publication “Zur Quantentheorie der Strahlung”, published in 1917.
CHARLES H TOWNES (1951) Charles Hard Townes, an American physicist invented the MASER (Microwave Amplification by Stimulated Emission of Radiation)
THEODORE H MAIMAN (1960) Maiman introduced first Laser using synthetic ruby rod (RUBY LASER) Lasers as bloodless surgical tool for T/t of cancers & as dental equipment . 1956,--exposed extracted tooth to prototype Ruby (694 nm) Laser, --- transmission of Laser energy was found. The first actual laser, based on a pink ruby crystal, was demonstrated in 1960 by at Hughes Research Laboratories.
LEON GOLDMAN(1965) Goldman established the first laser medical laboratory using ruby laser. 1960, Goldman and Polanyi and Jako developed Nd:YAG, CO2 lasers for surgery of oral cavity THE FATHER OF LASER MEDICINE
• In 1965 Taylor reported the histologic effect of ruby laser on the dental pulp. • The 1st application of LASER in maxillofacial surgery was by Lenz et al in 1977, who used argon laser to create a nasoantral window. • CO2 laser was 1st invented by Kumar Patel in 1964 and it was 1st applied to periodontal surgery by Pick in 1985. • In 1996, Use of lasers on hard tissue such as teeth or the bone of the mandible • • In 1997, laser armamentarium has been designed • 1997 - FDA gave clearance for first true dental hard tissue Er:YAG laser and the Er,Cr:YSGG a year later.
Light is a form of an electromagnetic energy which is basically waves of energy that has both electric and magnetic field component which are perpendicular to each other. Light consists of photons — “particles” with no mass which travel at the speed of light.
Long wavelength Low frequency Low energy Short wavelength High frequency High energy Non ionizing Ionizing
Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 700 nm
LASER PHYSICS
Energy of these atoms in excited states is provided externally by some energy source referred to as the “pump” source. Amplification by stimulated emission
Probability for an atom to absorb photon is same as probability for an excited atom to emit a photon via stimulated emission, The collection of real atoms will be a net absorber, not a net emitter, and amplification will not be possible. Hence , to make a laser, we have to create a “population inversion
Population inversion -- amplify a signal via stimulated emission, Most of the excited atoms in population emit spontaneously and do not contribute to the overall output A resonator = a system of mirrors that reflects undesirable (off-axis) photons out of the system and reflects the desirable (on-axis) photons back into the excited population where they can continue to be amplified. •Lasing medium is pumped continuously --- create a population inversion at lasing wavelength • Photons travel on- axis and off-axis •Photons on- axis will be reflected back into lasing medium & stimulate more excited atoms.
•Active medium •Pumping Mechanism •Optical resonator •Cooling system •Control Panel •Delivery system LASER COMPARTMENT
Arthur Shawlow said, “Hit it hard enough and anything will lase.
•(with mirrors at joints) – UV, visible & infrared lasers •(flexible tube with reflecting internal surfaces) – middle & far infrared lasers. •Fiber optics – visible & near infrared lasers LASER DELIVERY SYSTEM
FOCUSED DE-FOCUSED • Laser beam hits tissue at its focal point- narrowest diameter • Beam moved away from its focal point • Cutting mode • Wider area of tissue affected as beam • Ablative mode • Low level laser therapy LASER OPERATION PARAMETERS
CONTACT NON-CONTACT • Tip is in contact with tissue • Tip is kept 0.5 to 1 mm away from tissue • Concentrated delivery of laser energy • Laser energy delivered at the surface is reduced • Char tissue formation at tip • Tactile feedback is available
Basic modes of wavelength emission for dental lasers: Continuous wave emission: laser energy is emitted continuously produces constant tissue interaction. Equipped with a mechanical shutter with a time circuit to produce gated or super-pulsed energy to minimize some of undesirable residual thermal damage. Eg. CO2, Ar, and diode lasers Free-running pulse emission: very short bursts of laser It provides target tissue with thermal relaxation time to cool. Eg. Nd:YAG, Er:YAG, and Er,Cr:YSGG
LASERS CHARACTERISTICS Monochromatic Coherent Unidirectional Collimated Efficacy Laser beam= Single wavelength (visible or infrared) •Photon beams have same frequency •Waves are identical & phased • Constant phase relationship with time and phase ---COHERENT Perfectly parallel to directional light at very low average power levels lasers can produce required energy to perform specific fn.
CLASSIFICATION 1. According to wavelength:
2.Based on the penetration power of the beam: • Hard tissue lasers: Erbium lasers. • Soft tissue lasers: Diode, Nd:YAG,CO2 laser. 3.Based on the emission mode: • Continuous wave • Gated pulse • Free running pulsed
4.Based on the laser material used: • Gas lasers: CO2, Argon, He-Ne lasers • Liquid lasers: Dye lasers • Solid state lasers: Ruby , Nd:YAG lasers • Semiconductors: Gallium, Arsenide (diode laser).
5. According to ANSI & OHSA standards Class I : Low powered lasers that are safe to use. Class IIa : Low powered visible , hazardous only when viewed directly for longer than 1000 seconds. Class IIb : Low powered visible , hazardous when viewed for more than 0.25 seconds. Class IIIa : Medium powered ,hazardous if viewed for less than 0.25 seconds without magnifying optics. Class IIIb : Medium powered, hazardous when viewed directly. Class IV : High powered lasers, that produce ocular skin and fire hazards.
LASER EFFECT ON TISSUES Incident light energy will interact with a medium (eg oral tissue) that is denser than air, in one of four ways ≥50% back-scatter
Laser absorption characteristics: Laser emission mode: continuous beam, or forms of pulses with time Laser incident power (Joules per second) Laser power density (Watts per square centimetre): smaller the beam diameter, greater concentration of heat effects. Beam movement: relative to tissue site; rapid laser beam movement --- reduce heat build-up ----thermal relaxation. Endogenous coolant: blood flow. Exogenous coolant: water, air, pre-cooling of tissue SECONDARY FACTORS ARE: •Laser wavelength • Tissue (composition) and thickness • Surface wetness • Incident angle of beam, • Exposure time • Contact vs non-contact mode
LASER EFFECTS ARE DUE TO Depending on the time of irradiation and the power density, photochemical Biostimulation & Photodynamic therapy Clinical application in dentistry are: low level laser therapy (LLLT) & photodynamic therapy (PDT).  photo-thermal Photopyrolysis , photovaporolysis photoplasmolysis  photo-mechanical Photodisruption & Photoacoustic
 Photochemical effect: Biostimulation PDT: Association of a certain wavelength and a specific chromophore able to absorb the light. Tissue response in terms of change of covalent str LLLT: (Endre Meister in 1967) ---pain reduction & fast healing process • Work towards healing by stimulation of factors & processes, Below surgical threshold • Useful for pain relief, increased collagen growth & anti-inflammatory activity Photopyrolysis Photovaporolysis Photoplasmolysis Ascendent heat levels-phase transfer , liquid to vapor at 100 deg C Tissue removed by formation of electrically charged ions and particles in a semi-gaseous high energy state. Ascending temperature change from 60oC to 90oC, target tissue proteins undergo permanent morphologic change. Photothermal effect:
• When rapid pulses of light are incident ,they can be absorbed and resulting energy radiated as heat. • This heat causes detectable sound waves due to pressure variation in the surrounding medium. Photoacoustic: conversion between light and acoustic waves due to absorption and localized thermal excitation PHOTOMECHANICAL Disruption of tissue due to a range of phenomena, including such as Shock wave formation, Cavitations etc Action: • photoablation----fast thermal explosion & mechanical shock waves • photodisruption ----nonlinear tissue behavior , optical breakdown & mechanical shock waves
HARD AND SOFT TISSUE LASER ‘Hard’ and ‘soft’ based on their effect on tissue (not relate to target tissue types) • ‘Hard’, or surgical lasers---- high power lasers direct interaction. (photothermal) incident light energy is absorbed and converted into thermal energy which causes tissue change. • ‘Soft’, or ‘low-level’ lasers -----low power lasers an indirect interaction (photobiostimulation) eg. tissue warming, increase of local blood flow and production of endorphins. Eg. HeNe , GaAlAs diode, GaAs diode , defocused Co2 & Nd:YAG laser , Argon ,
- Laser soft tissue surgery (Nd:YAG) well accepted by child patients. BDJ, VOL 187, 1999
The depth and extent differ with laser wavelength, superficial with longer wavelengths---less oedema Deeper with shorter wavelength ----greater oedema central zone of tissue ablation Irreversible protein denaturation (coagulation, eschar) Reversible, reactionary Along thermal gradient
SOFT TISSUE • Cut, coagulate, ablate or vaporize target tissue elements • Sealing of small blood vessels • Sealing of small lymphatic vessels • Sterilizing of tissue- Eschar • Decreased post-operative tissue shrinkage BENEFITS OF LASER – TISSUE INTERACTION In dental hard tissue the water component is vapourized at 100 °c and the resulting jet of steam expands and then explodes the surrounding matter into small particles. This micro-explosion of the apatite crystal is termed SPALLATION
Effects of long wavelength laser light on hard dental tissue: Explosive vaporisation of water content of enamel & dentine, • Dissociation of tissue and ejection of micro-fragments Er:YAG Er,Cr:YSGG Co2 Affinity for ---- Hydroxyappatite Water chromophores
WHAT DOES THE OPERATOR CONTROL?
CO2 LASER LASER CHARACTERISTICS WAVELENGTH 9300, 9600, 10600 nm ACTIVE MEDIUM Carbon dioxide gas DELIVERY SYSTEM Articulated arm MODE OF OPERATION Continuous wave, gated pulsed mode. Used in focused and de-focused modes CHROMOPHORE Water, hydroxyapatite LIMITATION High risk of carbonisation ADVANTAGE Carbonized /charred layer acts as biological dressing
ARGON LASER LASER CHARACTERISTICS WAVELENGTH 488 – 514 nm ACTIVE MEDIUM Argon gas DELIVERY SYSTEM Optical fiber FIBER DIAMETER 300 microns MODE OF OPERATION Continuous wave CHROMOPHORE Melanin pigment, haemoglobin, hemosiderin APPLICATIONS Soft tissue only Pocket debridement and de- epithelialisation for GTR
DIODE LASER LASER CHARACTERISTICS WAVELENGTH 810 – 980 nm ACTIVE MEDIUM Semi-conductor diode DELIVERY SYSTEM Optical fiber- quartz or silica FIBER DIAMETER 300 microns MODE OF OPERATION Continuous wave, gated pulse mode Used in focused and de –focused modes CHROMOPHORE Melanin pigment, haemoglobin APPLICATIONS Primarily soft tissue applications- all minor surgical procedures
ND:YAG LASER (neodymium-doped yttrium aluminium garnet) LASER CHARACTERISTICS WAVELENGTH 1064 nm ACTIVE MEDIUM Neodymium in YAG crystal DELIVERY SYSTEM Optical fiber FIBER DIAMETER 300 microns MODE OF OPERATION Continuous wave, pulsed wave CHROMOPHORE Melanin pigment, haemoglobin, water APPLICATIONS Soft and hard tissue, Causes more thermal damage
LASER CHARACTERISTICS WAVELENGTH 2940 and 2780 nm ACTIVE MEDIUM Erbium ion embedded in YAG or YSGG crystal DELIVERY SYSTEM Articulated arm, hollow wave guide, FIBER DIAMETER Tip diameter – 0.6mm MODE OF OPERATION Continuous wave, free running pulsed mode. Used in focused and de- focused modes. CHROMOPHORE Water, hydroxyapatite Er:YAG LASER (erbium-doped yttrium aluminium garnet
Er,Cr:YSGG (2790 nm) --- active medium of a solid crystal of yttrium – scandium-gallium-garnet doped with erbium and chromium. Er:YAG (2940 nm) -----active medium of a solid crystal of yttrium-Al- Garnet doped with erbium. CHROMOPHORE: water & hydroxyapatite USES: • Caries removal and tooth preparation used with a water spray. •Healthy enamel surface can be modified for increased adhesion Er,Cr: YSGG & Er:YAG LASER
All dental soft tissue surgeries can be performed by soft tissue laser (LLLT), but the erbium (Er) family of lasers is the only group of lasers indicated for treatment of osseous tissue. Benefit of laser in prosthetic surgeries: 1. reduces bacteria at the surgical site 2. coagulates blood vessels. 3. minimizes scar formation. 4. reduces swelling and postoperative pain. 5. facilitates the overall treatment of prosthodontic patients. LASER IN PROSTHODONTICS
•Tuberosity , Torus / exostosis reduction •Soft tissue and residual ridge modification •Epulis fissuratum reduction •Denture stomatitis •Treatment of flabby ridges •Vestibuloplasty •frenectomies •Osseoectomy during tooth/root extraction or ridge contouring •Treatment of soft tissue and hard tissue undercuts. •Laser welding (Nd:YAG ) for Ni-Cr-Mo & Cr-Co-Mo alloys laser welding, 20%-50% higher values of tensile strength compared with soldering. LASER IN RPD
Immediate postoperative views of the maxilla (c) following frenectomy and vistibuloplasty and the mandible (d) following vistibuloplasty.
•Crown lengthening & Osseous lengthening (Erbium lasers ) •Soft tissue management around abutments ( Argon) •Troughing (Nd:YAG. replace need for retraction cord, electrocautery) •Formation of ovate pontic sites (Co2 laser) •Bleaching (Er:YAG and Er Cr:YSGG ) •Veneer removal (Er:YAG and Er Cr:YSGG ) •Tooth preparation (Er, Cr: YSGG ) •Removal of the carious lesion and cavity preparation. (Er: YAG laser – 1997) •Direct Fiber reinforced composite restoration (Er: YAG lasers ----- thermomechanical ablation by microexplosions of smear layer) •De-pigmentation of gingiva. (Diode, Nd:YAG, CO2 and erbium ) • Laser phototherapy (AsGaAl) •Dentinal hypersensitivity. (soft tissue laser and Er family) LASER IN FPD
Laser Specification Treatment effectively MOA He-Ne Senda et al. (1985). pulsed (5 Hz) CW mode 5.2 to 100%. increases the action potential of nerve Ga- Al-As diode- Matsumoto et al.(1985). CW for 0.5- 3 Minutes. 85-100% blocking the depolarization of C-fiber afferents. (Wakabayashi et al.1992- 1993) Nd:YAG - Matsumoto et al (1985) black ink as absorption enhancer , prevent any deep penetration into E/D/P Co2 Moritz et al.(1996). 1W for 5-10sec dentinal desiccation for temporary clinical relief (Fayad et al.1996). Er:YAG deposition of insoluble salts in the exposed dentinal tubules. Er, Cr: YSGG 0.5W for 30s thermo mechanical process
Laser handpiece: High-speed hand piece with fiber-optic tips instead of bur, Focal point approximately 1-2 mm Crown preparation Cutting enamel (6W,90% air,75% water), defocused mode for 30 sec- 1 min Placing gingival margin –(1.25 W, 50% air, 40% water )-- accuracy. Interproximal, buccal, lingual/palatal reduction --- ( 4W, 65% air, 55% water)  Finish Buccal cusp overlay and final margination ----( 2.25 W, 65% air, 55% ) Advantages: No anesthesis reqd. --- temporary paresthasia Accurate and faster Disadvantages: Trained dentist required for use. CROWN PREPERATION Hydrokinetic technology (laser-energized water to cut /ablate tissue)
EXCIMER LASER (308nm) one laser that offers precise ablation of tissues, fiber delivery, bactericidal effects, good transmission through water and enamel surface conditioning in one system. Very expensive and time consuming • Used for RCT
Gently washes away decay with laser- energized water droplets
Laser phototherapy: LLLT eg AsGaAl (gallium aluminum arsenide) 660 nm laser Promote soft tissue bio-modulation around prepared crown to ensure no inflammation signals is present in gingival tissue before final luting procedure Lasers: Argon, CO2, diode, erbium, and pulsed Nd:YAG LASER IN ESTHETICS Smile designing
i) Prototyping and CAD/CAM technology. Titanium plate for CD: CAD/CAM + LRF (Laser Rapid Forming) Laser scanner, reverse engineering software, and STL . Denture plate built layer-by-layer, on LRF system ii) Analysis of occlusion by CAD/CAM. laser scanner technique and 3D reconstruction in balanced cases. iii) Analysis of accuracy of impression by laser scanner. Scanning laser (3D) digitizer. It accurately and reliably measure dimensions of dental impression materials while avoiding subjective errors. LASER IN CD Lasers in prosthodontics – a review. Journal of Evolution of Medical and Dental Sciences/Volume1/ Issue4/October - 2012
 Socket sterilization & Implant site preparation Peri implantitis ( to vaporise any granulation tissue - Diode laser, CO2 laser and Er:YAG ) Preoperative frenectomy and tissue ablation  Debridement of implant surface (Er: Cr: YSGG ---2780 nm – uses ablative hydrokinetic process for decontamination & debridment) Second stage uncovering of implant (CO2 laser ) Repair of ailing implant. LLLT eg. diode soft laser (690 nm) used on contaminated surface for 60 sec after placement of toluidine blue O for 1 min. Reduced bacteria count by 92%. LASER IN IMPLANTOLOGY Gounder R, Gounder S. Laser science and its applications in prosthetic rehabilitation. J Lasers Med Sci. 2016;7(4):209-213.
3D Printing: 3D printing for both bony & soft tissue reconstruction, a model obtained from (CAD) & built in a layer by layer fashion. Various 3D printing techniques : •stereolithography, • multijet modelling, •SLS, •binder jetting , •fused deposition modelling. LASER IN MAXILLOFACIAL PROSTHESIS Gounder R, Gounder S. Laser science and its applications in prosthetic rehabilitation. J Lasers Med Sci. 2016;7(4):209-213.
1 .Laser cutting 2. Laser welding 3. Fabrication of prosthesis using CAD-CAM, DLMS, rapid prototyping etc. 4. Laser titanium sintering 5.Laser ablation of titanium surfaces 6.Laser-assisted HA coating 7.Laser welding of titanium components of prostheses. Lasers have (pulsed) for deposition of HA thin films on titanium implants. Also for surface treatment of titanium castings for ceramic bonding LASER IN LABORATORY
Laser microgroove implant— LASER LOK
Laser welding It is a union process based on localized fusion in the joint, through bombardment from a high-intensity, concentrated, monochromatic and coherent light beam. The area to be welded is protected by using an inert gas, usually argon or a mixture of inert gases.
Intraoral welding Based on creation of an electric arc btw two electrodes under an argon gas flux: Causing ---inter-digitations of titanium prisms • 1967 Gordon described the possibility of welding metallic portions •Initially, CO2 and Nd:YAG used ---- but Nd:YAG gained popularity (Shinoda et al, 1991- Yamagishi et al, 1993). •Nd:YAG laser to weld appliances, extra- and intra-orally, in dental office. Methods: “Syncrystallization” and “Mondani Electrowelder” •ILW technique is effective on all metals and alloys •Can be applied either with or without filler metal and shielding gas •Small spot size of the beam (0.6 mm), restrict high temperature within a very limited area. Limitations are: Effective only on titanium and its alloys, Cannot be used on patients with pacemaker, Some energy from welding process spreads to adjacent area (teeth, acrylic, ceramic, etc.).
Intraorally Welded Titanium Bar in the Immediate Loading Implants
Alloy Lasers Ti and its Alloy CW–CO2, Pulsed Nd:YAG laser, Fiber laser, Yb:YAG ytterbium Ceramics CW–CO2, KrF excimer laser, pulsed YAG Steel and its alloy Pulsed Nd:YAG, CW-laser, Photolytic iodine laser, CW–CO2 and diode laser Al alloy Pulsed Nd:YAG laser, CW–CO2, Fiber laser Gold Semiconductor laser, Nd:YAG laser LASER IN DENTAL MATERIALS
 Lasers are rapidly becoming the standard of care for many procedures performed by oral and maxillofacial surgeons  The reason for this transition is due to the fact that many procedures can be executed more efficiently and with less morbidity using lasers as compared to a scalpel, electrocautery or high frequency devices  Early lasers were bulky and historically used for major cases in operating theaters; but today, access to small, portable, office-based lasers with improved intraoral delivery systems have made it possible to treat even minor routine procedures in the clinic
Advantages  The advantages of laser surgery include:  Hemostasis and excellent field visibility  Precision  Enhanced infection control and elimination of bacteremia  Lack of mechanical tissue trauma  Reduced postoperative pain and edema  Reduced scarring and tissue shrinkage  Microsurgical capabilities  Less instruments at the site of operation  Asepsis due to non-contact tissue ablation and prevention of tumor seeding
Laser Osteotomy  Experimental laser osteotomies performed in vitro and in vivo using different wavelengths including excimer lasers, Er:YAG, CO2 and Ho:YAG lasers  The laser light emitted by Er:YAG and CO2 --- absorbed water Er:YAG laser--- absorbed by hydroxyapatite CO2 laser --- absorbed by collagen  Light microscopy, histologic sections and SEM revealed no charring, but a very thin basophilic zone next to the cut surface, while cutting the trabecular structures resulted in coagulation zone
Fibromas  Fibromas are often due to lip biting.  The soft tissue surgery can be performed using Laser HF using the fibroma removal mode (975nm, 5W, CW) without side effects or complications after surgery
Clinical appearance of a lower lip fibroma Use of Laser HF for soft tissue surgery Postsurgical view. Follow up two weeks after surgery.
Mucocele  Mucoceles of the lip can be unroofed, then excised with gland tissue using Laser HF, using fibroma removal mode (975nm, 5W, CW).  The wound margins may be sealed with a defocused beam without side effects or complications.  Re-epithelization takes about three weeks
Clinical appearance of the mucocele Unroofed lesion after first laser use Excision of the lesion together with adjacent salivary gland using diode laser Final postoperative view.
Palatal Lesions  Lesions of the soft palate such as traumatic fibromas in the soft palate can be treated using Laser HF, fibroma removal mode (975nm, 5W, CW).  Application of LLLT immediately after surgery may expedite healing (Acupuncture mode, 660nm, 90mW, 90s interval) without side effects or complications
Clinical appearance of the fibroma of the soft palate Usage of diode laser for soft tissue surgical procedure Application of LLLT immediately after surgery. Follow up three weeks after surgery
Epulis Fissuratum  Epulis fissuratum of the jaws can be removed using Laser HF, via a combination of Fibroma removal (975nm, 5W, CW) and Gingivectomy modes (975nm, 3W, 10ms, 1:2), followed by LLLT application immediately after the surgical procedure (Acupuncture mode, 660nm, 90mW, 90s interval).  The aPDT may also be performed (660nm, 50mW, 30s interval) without complications  Palatal fibroepithelial polyp and inflammatory papillary hyperplasia of the hard palate can be treated similarly using Laser HF using (Fibroma removal mode, 975nm, 5W, CW) in combination with loop of high frequency.  LLLT application (Acupuncture mode, 660nm, 90mW,90s interval) immediately after surgery
Clinical appearance of a maxillary epulis fissuratum Surgical procedure performed using diode laser Immediate postsurgical view. Application of the ''photosensitizer'', a coloring solution for aPDT, and photodynamic therapy using diode laser. b. Application of the diode laser.
Exposure of impacted teeth  Exposure of an impacted tooth (soft tissue impaction) can be done using Laser HF, (Gingivectomy mode, 975nm, 3W, CW).  After laser incision around the impacted crown, the mucosal tissue is removed with an elevator until the underlying crown is identified
Clinical view before surgery Incision using diode laser. Removal of the mucosal flap with an elevator. Immediate application of the orthodontic element.
Crown lengthening  Crown lengthening is easily done using lasers.  After raising the mucoperiosteal flap, selective osteotomy with the surgical bur is performed.  Subsequent to the suturing and frenectomy, laser gingivectomy using LaserHF (Gingivectomy mode, 975nm, 3W, 10ms, 1:2) for the lengthening of clinical crowns can be done
a. Treatment planning before surgery. b. Radiograph before surgery. a. Selective osteotomy after raising the mucoperiosteal flap. b. Selective osteotomy completed.
a. Subsequent to the suturing and frenectomy, gingivectomy using diode laser was performed.b. Frenectomy, gingivectomy completed.
Laser Doppler Flowmetry - To monitor pulpal and gingival blood flow - To assess tooth vitality • Laser Fluorescence for detection of caries • Laser Doppler Vibrometry to measure tooth mobility. LASER DIAGNOSTICS
PART OF EYE DAMAGED LASER TYPE • Corneal damage • Er Cr YSGG, Ho YAG, Er YAG, CO2 • Lens damage • Diode, Nd YAG, Ho YAG, Er Cr YSGG, Er • Aqueous damage • Ho YAG, Er Cr YSGG, Er YAG • Retinal damage • Argon, He Ne, diode, Nd YAG EYE DAMAGE
315 – 400 nm Eye Lens Damage 760 – 1400 nm Retinal Damage 1400 nm – 1 mm Corneal Damage
• Radiation absorbed in eye lens • Effects are delayed (e.g.; cataracts). Near Ultraviolet Wavelengths (315 - 400 nm) • Radiation transmitted to retina • Overexposure --- flash blindness or retinal burns and lesions. Near Infrared (760 - 1400 nm) • Radiation transmitted to cornea. • Overexposure --corneal burns. Far Infrared (1400 nm - 1 mm)
EYE PROTECTION Eye wear for patient Safety Glasses
PLUME CONTROL  Rapid rise in temperature causes cells to rupture  Release of heated plume -- particles, gases (e.g., hydrogen cyanide, benzene, and formaldehyde), tissue debris, viruses, and offensive odour  Also HPV, HIV, coagulase-negative Staphylococcus, Corynebacterium species, and Neisseria species) detected in laser plumes RECOMMENDATION:  High-filtration surgical masks,  Central room suction units and  Mechanical smoke exhaust systems (high volume laser smoke evacuation)
Laser Plume Face Mask Protection from particle size less than 0.1 micron
SHARPS  Scored laser tips of quartz fibers are considered sharps and need to be disposed according to standard waste disposal protocols
WARNING SIGNS
HOW TO MINIMIZE LASER HAZARD Engineering Control • Automatic features in built with the system to protect personals – Warning System, Interlock Administrative Control • Policies that limit exposure to laser hazards – Only for Authorized Personals Procedural Control • Standard Operating Procedure to be followed while working with lasers Beam Control • The use of beam blocks, beam tubes etc to minimize the Nominal Hazard Zone
LASER WARNING SYSTEM LASER CONNECTED INTERLOCK
FIRE & EXPLOSION HAZARD Class IV Lasers are associated with fire hazards Following things must always be kept in mind while operating such systems: • Wet or fire-retardant materials - in operative field • Use only non- combustible anesthetic agent • Nitrous Oxide supports combustion and should not be used • Avoid cleaning the tip with alcohol/spirit . Moistened gauze to be used just prior to firing • Store highly combustible or explosive materials outside • Know location and operation of the nearest fire extinguisher
LASER IN FUTURE 1. Laser tooth brush : Low level laser therapy (LLLT) can be used to treat dentinal hypersensitivity
2. Photobiomodulation laser treatment --- accelerates healing time and reduces inflammation. Also can be used in treatment of herpes lesions if virus detected early. 3. Nightlase laser therapy---- reduces snoring, increase airway space, enhance quality of sleep. 4. Smoothlase laser therapy (Stealth Facelift) ---- Cosmetic enhancement of face skin using dual laser energy. Skins around mouth, nose ,chin and upper neck is tightened for youthful appearance.
References •Gounder R, Gounder S. Laser science and its applications in prosthetic rehabilitation. J Lasers Med Sci. 2016;7(4):209-213. doi:10.15171/jlms.2016.37. •Durrani S. Laser and it’s Application in Prosthetic Dentistry. Int J Dent Med Res 2015;1(6):183-188. •S, Misra SK, Chopra D, Sharma P. Enlightening the path of dentistry: Lasers – A brief review. Indian J Dent Sci 2018;10:184-9. •Sandesh Gosawi, Sanajay Kumar et all. Lasers in prosthodontics- a review. Journal of Evolution of Medical and Dental Sciences 2012; 1(4): 624-33. •El khourani Wadie and Pr Amal El yamani. “Lasers in Fixed Prosthodontics”. Acta Scientific Dental Sciences 3.12 (2019): 99-103.
•Das Manjula et all. Lasers in Prosthodontics – Review. University J Dent Scie 2017; 3(2) : 09-12. • LJ Walsh . The current status of laser in Dentistry. Australian Dental Journal 2003 ; 48 : (3) 146-155 • Laser in Dentistry, Leo J.Miserendino/Robert M.pick, 1995 • Laser in dentistry: Dental clinic of North America Vol.44,no. 4 Oct. 2000 •Kaura S, Wangoo A, Singh R, Kaur S. Lasers in prosthodontics. Saint Int Dent J 2015;1:11-5 •Dental clinics of North America “ Lasers in Clinical dentistry”. Oct 2004. Vol 48. Issue 4 •Introduction to laser technology. –online access. • Fornaini C. Intraoral laser welding. INTECH Open Access Publisher; 2010 Aug 17.
We must accept finite disappointment, but never Lose infinite HOPE. Dr. Martin Luther King, Jr. THANK YOU

More Related Content

PPT
Laser in dentistry
byAnkit Patel
 
PPTX
LASER IN DENTISTRY
byAshish Ranghani
 
PPTX
Laser in dentistry
byHams Hamed
 
PPTX
Laser in prosthodontics
byDr. Devi Shankar
 
PPTX
Lasers in dentistry
byDipika Bumb, Indian Cancer Society, New Delhi
 
PPTX
Laser Dentistry
byJanine Rumbaoa
 
PPTX
Lasers in dentistry
byazam_786
 
PPTX
Lasers in Prosthetic Dentistry
byDr. Priyanka N. Khungar, PG student
 
Laser in dentistry
byAnkit Patel
 
LASER IN DENTISTRY
byAshish Ranghani
 
Laser in dentistry
byHams Hamed
 
Laser in prosthodontics
byDr. Devi Shankar
 
Lasers in dentistry
byDipika Bumb, Indian Cancer Society, New Delhi
 
Laser Dentistry
byJanine Rumbaoa
 
Lasers in dentistry
byazam_786
 
Lasers in Prosthetic Dentistry
byDr. Priyanka N. Khungar, PG student
 

What's hot

PPTX
Dental laser physics ( LASER in dentistry )
byAbdelrahman Mosaad
 
PPTX
Lasers and Its Use In Dentistry
bySahal Abu
 
PPTX
Lasers in Dentistry
byDinesh Raj
 
PPTX
Laser in prosthodontics
byRagi Al-emam
 
PPTX
LASERS USED IN OPERATIVE DENTISTRY
bydr_nabilz
 
PPTX
Lasers in Conservative dentistry
byDeeti Priya Rana
 
PPTX
LASERS IN ENDODONTICS....... Dr Jagadeesh Kodityala
byJagadeesh Kodityala
 
PPTX
LASERS IN PROSTHODONTICS
byJehan Dordi
 
PPTX
Lasers in operative dentistry
byHIMANI THAWALE
 
PPTX
Ideal radiography
byRevath Vyas Devulapalli
 
PPT
LASERS in endodontics.ppt
bydr richa singh
 
PPTX
Lasers in operative dentistry seminar ppt
byDr. M. Kishore
 
PPTX
Application of Lasers in Prosthodontics
byDr. Talib Amin Naqash
 
PPTX
CBCT.pptx
byAyushiGautam41
 
PPTX
Irrigants and Irrigation Devices
byDr. Sahana Umesh
 
PPTX
Applications of lasers in endodontics
byDeeti Priya Rana
 
PPTX
Lasers and its applications in conservative dentistry
byDr. Preeti Rastogi
 
PPTX
LASER in Periodontics - Session 2
bySuman Mukherjee
 
PPTX
The Application of Lasers in Dentistry
byFrank Licht RDH, BSDH, MSDH
 
PDF
Lasers in dentistry or Dental lasers
bysurabhisoumya1
 
Dental laser physics ( LASER in dentistry )
byAbdelrahman Mosaad
 
Lasers and Its Use In Dentistry
bySahal Abu
 
Lasers in Dentistry
byDinesh Raj
 
Laser in prosthodontics
byRagi Al-emam
 
LASERS USED IN OPERATIVE DENTISTRY
bydr_nabilz
 
Lasers in Conservative dentistry
byDeeti Priya Rana
 
LASERS IN ENDODONTICS....... Dr Jagadeesh Kodityala
byJagadeesh Kodityala
 
LASERS IN PROSTHODONTICS
byJehan Dordi
 
Lasers in operative dentistry
byHIMANI THAWALE
 
Ideal radiography
byRevath Vyas Devulapalli
 
LASERS in endodontics.ppt
bydr richa singh
 
Lasers in operative dentistry seminar ppt
byDr. M. Kishore
 
Application of Lasers in Prosthodontics
byDr. Talib Amin Naqash
 
CBCT.pptx
byAyushiGautam41
 
Irrigants and Irrigation Devices
byDr. Sahana Umesh
 
Applications of lasers in endodontics
byDeeti Priya Rana
 
Lasers and its applications in conservative dentistry
byDr. Preeti Rastogi
 
LASER in Periodontics - Session 2
bySuman Mukherjee
 
The Application of Lasers in Dentistry
byFrank Licht RDH, BSDH, MSDH
 
Lasers in dentistry or Dental lasers
bysurabhisoumya1
 

Similar to Laser

PPTX
15. LASERS.pptx for lasers in conservative dentistry
byNikhilPatilKarhale
 
PPTX
LASERS IN PERIODONTICS -PROS, CONS , ADVANCES
bysusmithaa padmanabhan
 
PPTX
Laser in Conservative & Endodontics.pptx
byvanitha445358
 
PPTX
Lasers in prosthodontics
byDrSurajSharma1
 
PPTX
Lasers in conservative dentistry and endodontics.pptx
byDr Prashanth Sharma
 
PPTX
Lasers
byDr Heena Sharma
 
PPT
Lasers and its application in Periodontics.ppt
bymalti19
 
PPTX
LASERS IN PROSTHODONTICS An Overview Part 1.pptx
byAswathySudhakaran4
 
PPTX
Lasers in oral surgery
byTejal Ragji
 
PPTX
Lasers in oral and maxillofacial surgery .pptx
bywanidayim1
 
PPTX
Lasers in dentistry. sameera
byDr VenuSameera Panthagada
 
PPTX
Laser and orthodontic the meeting point
byAghimien Osaronse
 
PPTX
Lasers in periodontics
byANIL KUMAR
 
PPTX
lasers in periodontics and it's application
byManasa Ambati
 
PPT
Lasers and its application in periodontics
byShilpa Shiv
 
PPTX
LASER in Periodontics - Session 1
bySuman Mukherjee
 
PPTX
Lasers in oral and maxillofacial surgery
byJeff Zacharia
 
PPTX
Lasers in orthodontics Diagnosisand management.pptx
byAnagha Prasad
 
PPTX
laser in dentistry in oral premalignant lesions.pptx
byMayuri Sonole
 
PPTX
Lasers in omfs
byDrFirdousMulla
 
15. LASERS.pptx for lasers in conservative dentistry
byNikhilPatilKarhale
 
LASERS IN PERIODONTICS -PROS, CONS , ADVANCES
bysusmithaa padmanabhan
 
Laser in Conservative & Endodontics.pptx
byvanitha445358
 
Lasers in prosthodontics
byDrSurajSharma1
 
Lasers in conservative dentistry and endodontics.pptx
byDr Prashanth Sharma
 
Lasers
byDr Heena Sharma
 
Lasers and its application in Periodontics.ppt
bymalti19
 
LASERS IN PROSTHODONTICS An Overview Part 1.pptx
byAswathySudhakaran4
 
Lasers in oral surgery
byTejal Ragji
 
Lasers in oral and maxillofacial surgery .pptx
bywanidayim1
 
Lasers in dentistry. sameera
byDr VenuSameera Panthagada
 
Laser and orthodontic the meeting point
byAghimien Osaronse
 
Lasers in periodontics
byANIL KUMAR
 
lasers in periodontics and it's application
byManasa Ambati
 
Lasers and its application in periodontics
byShilpa Shiv
 
LASER in Periodontics - Session 1
bySuman Mukherjee
 
Lasers in oral and maxillofacial surgery
byJeff Zacharia
 
Lasers in orthodontics Diagnosisand management.pptx
byAnagha Prasad
 
laser in dentistry in oral premalignant lesions.pptx
byMayuri Sonole
 
Lasers in omfs
byDrFirdousMulla
 

Recently uploaded

PPTX
LYMPHATIC SYSTEM (Human Anatomy & Physiology-II)
byPranaliChandurkar2
 
PPTX
ANATOMY OF THE PERICARDIUM OF THE HEART
bySanyamarora25
 
PPTX
Spirituality and Mental Health - therapy perspectives and formulation pptx
bySaju Pj
 
PDF
Public Health Status of Nepal: Data, Facts, and Resources
byPublic Health Concern Nepal
 
PPTX
Pain Pathway, Sensitization & Classification of Pain: A Mechanism-Based Clini...
byDaradia: The Pain Clinic
 
PPTX
LIPIDS Homeostasis (digestion, metabolism, absorption and excretion.pptx
bysfarzanazubair
 
PPTX
IMPELLA DEVICE IN THE MANAGEMENT OF CARDIOGENIC SHOCK
byraycebright
 
PPT
Pathways to Personalized Remission in CLL: Leveraging Targeted Standards & Ne...
byPVI, PeerView Institute for Medical Education
 
PPTX
ELECTRON TRANSPORT CHAIN.complete overview pptx
bysfarzanazubair
 
PDF
Ayurvedic Cosmetology: A Hands-On Training in Skin & Hair Care
byDr. Amrutha Sajeevan
 
PPTX
Lecture on “Conservative Management of PPH Vs Caesarean Hysterectomy” at 54th...
byNiranjan Chavan
 
PPTX
FORMULATION AND DEVELOPMENT(PHARMACY).pptx
byGRTIPER
 
PPTX
NATURAL HISTORY OF DISEASE : Definitions , key terms & Example
byZoha Sajjad Hussain
 
PPTX
Physiology Of Respiratory System Pediatric View.pptx
bydoshiharsh814
 
PPTX
Evidence based oral medicine in dentistry .pptx
bymrugajoshi101
 
PPTX
Imaging approach to Intraventricular tumors
byDr. Aryan (Anish Dhakal)
 
PPTX
study on herbal medicine (ginger) pharma
byNAVNEET RAJ
 
PPTX
Postpartum hemorrhage by Awimbilla Mabel
bywimbelba
 
PPTX
Levels of Linguistics SLP-1 lecture 6 .pptx
byDr Zonera Khalid PT
 
PPTX
Unit-1.pptx Herbs as raw material, Biodynamic Agriculture
byChaitali Bhavar
 
LYMPHATIC SYSTEM (Human Anatomy & Physiology-II)
byPranaliChandurkar2
 
ANATOMY OF THE PERICARDIUM OF THE HEART
bySanyamarora25
 
Spirituality and Mental Health - therapy perspectives and formulation pptx
bySaju Pj
 
Public Health Status of Nepal: Data, Facts, and Resources
byPublic Health Concern Nepal
 
Pain Pathway, Sensitization & Classification of Pain: A Mechanism-Based Clini...
byDaradia: The Pain Clinic
 
LIPIDS Homeostasis (digestion, metabolism, absorption and excretion.pptx
bysfarzanazubair
 
IMPELLA DEVICE IN THE MANAGEMENT OF CARDIOGENIC SHOCK
byraycebright
 
Pathways to Personalized Remission in CLL: Leveraging Targeted Standards & Ne...
byPVI, PeerView Institute for Medical Education
 
ELECTRON TRANSPORT CHAIN.complete overview pptx
bysfarzanazubair
 
Ayurvedic Cosmetology: A Hands-On Training in Skin & Hair Care
byDr. Amrutha Sajeevan
 
Lecture on “Conservative Management of PPH Vs Caesarean Hysterectomy” at 54th...
byNiranjan Chavan
 
FORMULATION AND DEVELOPMENT(PHARMACY).pptx
byGRTIPER
 
NATURAL HISTORY OF DISEASE : Definitions , key terms & Example
byZoha Sajjad Hussain
 
Physiology Of Respiratory System Pediatric View.pptx
bydoshiharsh814
 
Evidence based oral medicine in dentistry .pptx
bymrugajoshi101
 
Imaging approach to Intraventricular tumors
byDr. Aryan (Anish Dhakal)
 
study on herbal medicine (ginger) pharma
byNAVNEET RAJ
 
Postpartum hemorrhage by Awimbilla Mabel
bywimbelba
 
Levels of Linguistics SLP-1 lecture 6 .pptx
byDr Zonera Khalid PT
 
Unit-1.pptx Herbs as raw material, Biodynamic Agriculture
byChaitali Bhavar
 

Laser

  • 1.
  • 2.
    • INTRODUCTION • HISTORY •LASER PHYSICS • LASER COMPARTMENT AND DELIVERY SYSTEM • LASERCLASSIFICATION • LASER EFFECTS ON TISSUE • MOST COMMON LASERS IN DENTISTRY • LASER APPLICATION IN PROSTHODONTICS • LASERS IN RPD, CD, FPD, ESTHETICS, IMPLANT, MAXILLOFACIAL PROSTHESIS, DENTAL MATERIALS, USE IN LABORATORY • LASER IN ORAL SURGERY • LASER IN DIAGNOSIS • DENTAL LASERS IN FUTURE • LASER SAFETY • REFERENCES CONTENTS
  • 3.
    INTRODUCTION • LASER =“light amplification by stimulated emission of radiation” • Lasers are devices that produce beams of coherent and very high intensity light. • An alternative to traditional halogen curing light, laser now has become the instrument of choice, in many dental applications. • Its advancements in the field of dentistry are playing a major role in patient care and well being
  • 4.
    HISTORY ALBERT EINSTEIN 1915,Neils Bohr’s atomic model -- basis for quantum mechanics and, useful in demonstrating laser principles Einstein credited with development of Laser theory. Coin the term “Stimulated Emission” in his publication “Zur Quantentheorie der Strahlung”, published in 1917.
  • 5.
    CHARLES H TOWNES(1951) Charles Hard Townes, an American physicist invented the MASER (Microwave Amplification by Stimulated Emission of Radiation)
  • 6.
    THEODORE H MAIMAN (1960) Maimanintroduced first Laser using synthetic ruby rod (RUBY LASER) Lasers as bloodless surgical tool for T/t of cancers & as dental equipment . 1956,--exposed extracted tooth to prototype Ruby (694 nm) Laser, --- transmission of Laser energy was found. The first actual laser, based on a pink ruby crystal, was demonstrated in 1960 by at Hughes Research Laboratories.
  • 7.
    LEON GOLDMAN(1965) Goldman establishedthe first laser medical laboratory using ruby laser. 1960, Goldman and Polanyi and Jako developed Nd:YAG, CO2 lasers for surgery of oral cavity THE FATHER OF LASER MEDICINE
  • 8.
    • In 1965Taylor reported the histologic effect of ruby laser on the dental pulp. • The 1st application of LASER in maxillofacial surgery was by Lenz et al in 1977, who used argon laser to create a nasoantral window. • CO2 laser was 1st invented by Kumar Patel in 1964 and it was 1st applied to periodontal surgery by Pick in 1985. • In 1996, Use of lasers on hard tissue such as teeth or the bone of the mandible • • In 1997, laser armamentarium has been designed • 1997 - FDA gave clearance for first true dental hard tissue Er:YAG laser and the Er,Cr:YSGG a year later.
  • 9.
    Light is aform of an electromagnetic energy which is basically waves of energy that has both electric and magnetic field component which are perpendicular to each other. Light consists of photons — “particles” with no mass which travel at the speed of light.
  • 10.
    Long wavelength Low frequency Lowenergy Short wavelength High frequency High energy Non ionizing Ionizing
  • 11.
    Electromagnetic radiation inthis range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 700 nm
  • 12.
  • 14.
    Energy of theseatoms in excited states is provided externally by some energy source referred to as the “pump” source. Amplification by stimulated emission
  • 15.
    Probability for anatom to absorb photon is same as probability for an excited atom to emit a photon via stimulated emission, The collection of real atoms will be a net absorber, not a net emitter, and amplification will not be possible. Hence , to make a laser, we have to create a “population inversion
  • 16.
    Population inversion --amplify a signal via stimulated emission, Most of the excited atoms in population emit spontaneously and do not contribute to the overall output A resonator = a system of mirrors that reflects undesirable (off-axis) photons out of the system and reflects the desirable (on-axis) photons back into the excited population where they can continue to be amplified. •Lasing medium is pumped continuously --- create a population inversion at lasing wavelength • Photons travel on- axis and off-axis •Photons on- axis will be reflected back into lasing medium & stimulate more excited atoms.
  • 17.
    •Active medium •Pumping Mechanism •Optical resonator •Coolingsystem •Control Panel •Delivery system LASER COMPARTMENT
  • 18.
    Arthur Shawlow said,“Hit it hard enough and anything will lase.
  • 19.
    •(with mirrors atjoints) – UV, visible & infrared lasers •(flexible tube with reflecting internal surfaces) – middle & far infrared lasers. •Fiber optics – visible & near infrared lasers LASER DELIVERY SYSTEM
  • 21.
    FOCUSED DE-FOCUSED • Laserbeam hits tissue at its focal point- narrowest diameter • Beam moved away from its focal point • Cutting mode • Wider area of tissue affected as beam • Ablative mode • Low level laser therapy LASER OPERATION PARAMETERS
  • 22.
    CONTACT NON-CONTACT • Tipis in contact with tissue • Tip is kept 0.5 to 1 mm away from tissue • Concentrated delivery of laser energy • Laser energy delivered at the surface is reduced • Char tissue formation at tip • Tactile feedback is available
  • 23.
    Basic modes ofwavelength emission for dental lasers: Continuous wave emission: laser energy is emitted continuously produces constant tissue interaction. Equipped with a mechanical shutter with a time circuit to produce gated or super-pulsed energy to minimize some of undesirable residual thermal damage. Eg. CO2, Ar, and diode lasers Free-running pulse emission: very short bursts of laser It provides target tissue with thermal relaxation time to cool. Eg. Nd:YAG, Er:YAG, and Er,Cr:YSGG
  • 24.
    LASERS CHARACTERISTICS Monochromatic Coherent Unidirectional Collimated Efficacy Laser beam=Single wavelength (visible or infrared) •Photon beams have same frequency •Waves are identical & phased • Constant phase relationship with time and phase ---COHERENT Perfectly parallel to directional light at very low average power levels lasers can produce required energy to perform specific fn.
  • 26.
  • 28.
    2.Based on thepenetration power of the beam: • Hard tissue lasers: Erbium lasers. • Soft tissue lasers: Diode, Nd:YAG,CO2 laser. 3.Based on the emission mode: • Continuous wave • Gated pulse • Free running pulsed
  • 29.
    4.Based on thelaser material used: • Gas lasers: CO2, Argon, He-Ne lasers • Liquid lasers: Dye lasers • Solid state lasers: Ruby , Nd:YAG lasers • Semiconductors: Gallium, Arsenide (diode laser).
  • 30.
    5. According toANSI & OHSA standards Class I : Low powered lasers that are safe to use. Class IIa : Low powered visible , hazardous only when viewed directly for longer than 1000 seconds. Class IIb : Low powered visible , hazardous when viewed for more than 0.25 seconds. Class IIIa : Medium powered ,hazardous if viewed for less than 0.25 seconds without magnifying optics. Class IIIb : Medium powered, hazardous when viewed directly. Class IV : High powered lasers, that produce ocular skin and fire hazards.
  • 31.
    LASER EFFECT ONTISSUES Incident light energy will interact with a medium (eg oral tissue) that is denser than air, in one of four ways ≥50% back-scatter
  • 32.
    Laser absorption characteristics: Laseremission mode: continuous beam, or forms of pulses with time Laser incident power (Joules per second) Laser power density (Watts per square centimetre): smaller the beam diameter, greater concentration of heat effects. Beam movement: relative to tissue site; rapid laser beam movement --- reduce heat build-up ----thermal relaxation. Endogenous coolant: blood flow. Exogenous coolant: water, air, pre-cooling of tissue SECONDARY FACTORS ARE: •Laser wavelength • Tissue (composition) and thickness • Surface wetness • Incident angle of beam, • Exposure time • Contact vs non-contact mode
  • 33.
    LASER EFFECTS AREDUE TO Depending on the time of irradiation and the power density, photochemical Biostimulation & Photodynamic therapy Clinical application in dentistry are: low level laser therapy (LLLT) & photodynamic therapy (PDT).  photo-thermal Photopyrolysis , photovaporolysis photoplasmolysis  photo-mechanical Photodisruption & Photoacoustic
  • 34.
     Photochemical effect: Biostimulation PDT:Association of a certain wavelength and a specific chromophore able to absorb the light. Tissue response in terms of change of covalent str LLLT: (Endre Meister in 1967) ---pain reduction & fast healing process • Work towards healing by stimulation of factors & processes, Below surgical threshold • Useful for pain relief, increased collagen growth & anti-inflammatory activity Photopyrolysis Photovaporolysis Photoplasmolysis Ascendent heat levels-phase transfer , liquid to vapor at 100 deg C Tissue removed by formation of electrically charged ions and particles in a semi-gaseous high energy state. Ascending temperature change from 60oC to 90oC, target tissue proteins undergo permanent morphologic change. Photothermal effect:
  • 36.
    • When rapidpulses of light are incident ,they can be absorbed and resulting energy radiated as heat. • This heat causes detectable sound waves due to pressure variation in the surrounding medium. Photoacoustic: conversion between light and acoustic waves due to absorption and localized thermal excitation PHOTOMECHANICAL Disruption of tissue due to a range of phenomena, including such as Shock wave formation, Cavitations etc Action: • photoablation----fast thermal explosion & mechanical shock waves • photodisruption ----nonlinear tissue behavior , optical breakdown & mechanical shock waves
  • 37.
    HARD AND SOFTTISSUE LASER ‘Hard’ and ‘soft’ based on their effect on tissue (not relate to target tissue types) • ‘Hard’, or surgical lasers---- high power lasers direct interaction. (photothermal) incident light energy is absorbed and converted into thermal energy which causes tissue change. • ‘Soft’, or ‘low-level’ lasers -----low power lasers an indirect interaction (photobiostimulation) eg. tissue warming, increase of local blood flow and production of endorphins. Eg. HeNe , GaAlAs diode, GaAs diode , defocused Co2 & Nd:YAG laser , Argon ,
  • 39.
    - Laser softtissue surgery (Nd:YAG) well accepted by child patients. BDJ, VOL 187, 1999
  • 40.
    The depth andextent differ with laser wavelength, superficial with longer wavelengths---less oedema Deeper with shorter wavelength ----greater oedema central zone of tissue ablation Irreversible protein denaturation (coagulation, eschar) Reversible, reactionary Along thermal gradient
  • 41.
    SOFT TISSUE • Cut,coagulate, ablate or vaporize target tissue elements • Sealing of small blood vessels • Sealing of small lymphatic vessels • Sterilizing of tissue- Eschar • Decreased post-operative tissue shrinkage BENEFITS OF LASER – TISSUE INTERACTION In dental hard tissue the water component is vapourized at 100 °c and the resulting jet of steam expands and then explodes the surrounding matter into small particles. This micro-explosion of the apatite crystal is termed SPALLATION
  • 42.
    Effects of longwavelength laser light on hard dental tissue: Explosive vaporisation of water content of enamel & dentine, • Dissociation of tissue and ejection of micro-fragments Er:YAG Er,Cr:YSGG Co2 Affinity for ---- Hydroxyappatite Water chromophores
  • 43.
    WHAT DOES THEOPERATOR CONTROL?
  • 44.
    CO2 LASER LASER CHARACTERISTICS WAVELENGTH9300, 9600, 10600 nm ACTIVE MEDIUM Carbon dioxide gas DELIVERY SYSTEM Articulated arm MODE OF OPERATION Continuous wave, gated pulsed mode. Used in focused and de-focused modes CHROMOPHORE Water, hydroxyapatite LIMITATION High risk of carbonisation ADVANTAGE Carbonized /charred layer acts as biological dressing
  • 45.
    ARGON LASER LASER CHARACTERISTICS WAVELENGTH488 – 514 nm ACTIVE MEDIUM Argon gas DELIVERY SYSTEM Optical fiber FIBER DIAMETER 300 microns MODE OF OPERATION Continuous wave CHROMOPHORE Melanin pigment, haemoglobin, hemosiderin APPLICATIONS Soft tissue only Pocket debridement and de- epithelialisation for GTR
  • 46.
    DIODE LASER LASER CHARACTERISTICS WAVELENGTH810 – 980 nm ACTIVE MEDIUM Semi-conductor diode DELIVERY SYSTEM Optical fiber- quartz or silica FIBER DIAMETER 300 microns MODE OF OPERATION Continuous wave, gated pulse mode Used in focused and de –focused modes CHROMOPHORE Melanin pigment, haemoglobin APPLICATIONS Primarily soft tissue applications- all minor surgical procedures
  • 47.
    ND:YAG LASER (neodymium-doped yttriumaluminium garnet) LASER CHARACTERISTICS WAVELENGTH 1064 nm ACTIVE MEDIUM Neodymium in YAG crystal DELIVERY SYSTEM Optical fiber FIBER DIAMETER 300 microns MODE OF OPERATION Continuous wave, pulsed wave CHROMOPHORE Melanin pigment, haemoglobin, water APPLICATIONS Soft and hard tissue, Causes more thermal damage
  • 48.
    LASER CHARACTERISTICS WAVELENGTH 2940and 2780 nm ACTIVE MEDIUM Erbium ion embedded in YAG or YSGG crystal DELIVERY SYSTEM Articulated arm, hollow wave guide, FIBER DIAMETER Tip diameter – 0.6mm MODE OF OPERATION Continuous wave, free running pulsed mode. Used in focused and de- focused modes. CHROMOPHORE Water, hydroxyapatite Er:YAG LASER (erbium-doped yttrium aluminium garnet
  • 49.
    Er,Cr:YSGG (2790 nm)--- active medium of a solid crystal of yttrium – scandium-gallium-garnet doped with erbium and chromium. Er:YAG (2940 nm) -----active medium of a solid crystal of yttrium-Al- Garnet doped with erbium. CHROMOPHORE: water & hydroxyapatite USES: • Caries removal and tooth preparation used with a water spray. •Healthy enamel surface can be modified for increased adhesion Er,Cr: YSGG & Er:YAG LASER
  • 51.
    All dental softtissue surgeries can be performed by soft tissue laser (LLLT), but the erbium (Er) family of lasers is the only group of lasers indicated for treatment of osseous tissue. Benefit of laser in prosthetic surgeries: 1. reduces bacteria at the surgical site 2. coagulates blood vessels. 3. minimizes scar formation. 4. reduces swelling and postoperative pain. 5. facilitates the overall treatment of prosthodontic patients. LASER IN PROSTHODONTICS
  • 52.
    •Tuberosity , Torus/ exostosis reduction •Soft tissue and residual ridge modification •Epulis fissuratum reduction •Denture stomatitis •Treatment of flabby ridges •Vestibuloplasty •frenectomies •Osseoectomy during tooth/root extraction or ridge contouring •Treatment of soft tissue and hard tissue undercuts. •Laser welding (Nd:YAG ) for Ni-Cr-Mo & Cr-Co-Mo alloys laser welding, 20%-50% higher values of tensile strength compared with soldering. LASER IN RPD
  • 53.
    Immediate postoperative viewsof the maxilla (c) following frenectomy and vistibuloplasty and the mandible (d) following vistibuloplasty.
  • 54.
    •Crown lengthening &Osseous lengthening (Erbium lasers ) •Soft tissue management around abutments ( Argon) •Troughing (Nd:YAG. replace need for retraction cord, electrocautery) •Formation of ovate pontic sites (Co2 laser) •Bleaching (Er:YAG and Er Cr:YSGG ) •Veneer removal (Er:YAG and Er Cr:YSGG ) •Tooth preparation (Er, Cr: YSGG ) •Removal of the carious lesion and cavity preparation. (Er: YAG laser – 1997) •Direct Fiber reinforced composite restoration (Er: YAG lasers ----- thermomechanical ablation by microexplosions of smear layer) •De-pigmentation of gingiva. (Diode, Nd:YAG, CO2 and erbium ) • Laser phototherapy (AsGaAl) •Dentinal hypersensitivity. (soft tissue laser and Er family) LASER IN FPD
  • 56.
    Laser Specification Treatment effectively MOA He-Ne Sendaet al. (1985). pulsed (5 Hz) CW mode 5.2 to 100%. increases the action potential of nerve Ga- Al-As diode- Matsumoto et al.(1985). CW for 0.5- 3 Minutes. 85-100% blocking the depolarization of C-fiber afferents. (Wakabayashi et al.1992- 1993) Nd:YAG - Matsumoto et al (1985) black ink as absorption enhancer , prevent any deep penetration into E/D/P Co2 Moritz et al.(1996). 1W for 5-10sec dentinal desiccation for temporary clinical relief (Fayad et al.1996). Er:YAG deposition of insoluble salts in the exposed dentinal tubules. Er, Cr: YSGG 0.5W for 30s thermo mechanical process
  • 57.
    Laser handpiece: High-speedhand piece with fiber-optic tips instead of bur, Focal point approximately 1-2 mm Crown preparation Cutting enamel (6W,90% air,75% water), defocused mode for 30 sec- 1 min Placing gingival margin –(1.25 W, 50% air, 40% water )-- accuracy. Interproximal, buccal, lingual/palatal reduction --- ( 4W, 65% air, 55% water)  Finish Buccal cusp overlay and final margination ----( 2.25 W, 65% air, 55% ) Advantages: No anesthesis reqd. --- temporary paresthasia Accurate and faster Disadvantages: Trained dentist required for use. CROWN PREPERATION Hydrokinetic technology (laser-energized water to cut /ablate tissue)
  • 58.
    EXCIMER LASER (308nm) onelaser that offers precise ablation of tissues, fiber delivery, bactericidal effects, good transmission through water and enamel surface conditioning in one system. Very expensive and time consuming • Used for RCT
  • 59.
    Gently washes awaydecay with laser- energized water droplets
  • 60.
    Laser phototherapy: LLLT egAsGaAl (gallium aluminum arsenide) 660 nm laser Promote soft tissue bio-modulation around prepared crown to ensure no inflammation signals is present in gingival tissue before final luting procedure Lasers: Argon, CO2, diode, erbium, and pulsed Nd:YAG LASER IN ESTHETICS Smile designing
  • 61.
    i) Prototyping andCAD/CAM technology. Titanium plate for CD: CAD/CAM + LRF (Laser Rapid Forming) Laser scanner, reverse engineering software, and STL . Denture plate built layer-by-layer, on LRF system ii) Analysis of occlusion by CAD/CAM. laser scanner technique and 3D reconstruction in balanced cases. iii) Analysis of accuracy of impression by laser scanner. Scanning laser (3D) digitizer. It accurately and reliably measure dimensions of dental impression materials while avoiding subjective errors. LASER IN CD Lasers in prosthodontics – a review. Journal of Evolution of Medical and Dental Sciences/Volume1/ Issue4/October - 2012
  • 62.
     Socket sterilization& Implant site preparation Peri implantitis ( to vaporise any granulation tissue - Diode laser, CO2 laser and Er:YAG ) Preoperative frenectomy and tissue ablation  Debridement of implant surface (Er: Cr: YSGG ---2780 nm – uses ablative hydrokinetic process for decontamination & debridment) Second stage uncovering of implant (CO2 laser ) Repair of ailing implant. LLLT eg. diode soft laser (690 nm) used on contaminated surface for 60 sec after placement of toluidine blue O for 1 min. Reduced bacteria count by 92%. LASER IN IMPLANTOLOGY Gounder R, Gounder S. Laser science and its applications in prosthetic rehabilitation. J Lasers Med Sci. 2016;7(4):209-213.
  • 64.
    3D Printing: 3D printingfor both bony & soft tissue reconstruction, a model obtained from (CAD) & built in a layer by layer fashion. Various 3D printing techniques : •stereolithography, • multijet modelling, •SLS, •binder jetting , •fused deposition modelling. LASER IN MAXILLOFACIAL PROSTHESIS Gounder R, Gounder S. Laser science and its applications in prosthetic rehabilitation. J Lasers Med Sci. 2016;7(4):209-213.
  • 65.
    1 .Laser cutting 2.Laser welding 3. Fabrication of prosthesis using CAD-CAM, DLMS, rapid prototyping etc. 4. Laser titanium sintering 5.Laser ablation of titanium surfaces 6.Laser-assisted HA coating 7.Laser welding of titanium components of prostheses. Lasers have (pulsed) for deposition of HA thin films on titanium implants. Also for surface treatment of titanium castings for ceramic bonding LASER IN LABORATORY
  • 66.
  • 67.
    Laser welding It isa union process based on localized fusion in the joint, through bombardment from a high-intensity, concentrated, monochromatic and coherent light beam. The area to be welded is protected by using an inert gas, usually argon or a mixture of inert gases.
  • 68.
    Intraoral welding Based oncreation of an electric arc btw two electrodes under an argon gas flux: Causing ---inter-digitations of titanium prisms • 1967 Gordon described the possibility of welding metallic portions •Initially, CO2 and Nd:YAG used ---- but Nd:YAG gained popularity (Shinoda et al, 1991- Yamagishi et al, 1993). •Nd:YAG laser to weld appliances, extra- and intra-orally, in dental office. Methods: “Syncrystallization” and “Mondani Electrowelder” •ILW technique is effective on all metals and alloys •Can be applied either with or without filler metal and shielding gas •Small spot size of the beam (0.6 mm), restrict high temperature within a very limited area. Limitations are: Effective only on titanium and its alloys, Cannot be used on patients with pacemaker, Some energy from welding process spreads to adjacent area (teeth, acrylic, ceramic, etc.).
  • 69.
    Intraorally Welded TitaniumBar in the Immediate Loading Implants
  • 71.
    Alloy Lasers Ti andits Alloy CW–CO2, Pulsed Nd:YAG laser, Fiber laser, Yb:YAG ytterbium Ceramics CW–CO2, KrF excimer laser, pulsed YAG Steel and its alloy Pulsed Nd:YAG, CW-laser, Photolytic iodine laser, CW–CO2 and diode laser Al alloy Pulsed Nd:YAG laser, CW–CO2, Fiber laser Gold Semiconductor laser, Nd:YAG laser LASER IN DENTAL MATERIALS
  • 73.
     Lasers arerapidly becoming the standard of care for many procedures performed by oral and maxillofacial surgeons  The reason for this transition is due to the fact that many procedures can be executed more efficiently and with less morbidity using lasers as compared to a scalpel, electrocautery or high frequency devices  Early lasers were bulky and historically used for major cases in operating theaters; but today, access to small, portable, office-based lasers with improved intraoral delivery systems have made it possible to treat even minor routine procedures in the clinic
  • 74.
    Advantages  The advantagesof laser surgery include:  Hemostasis and excellent field visibility  Precision  Enhanced infection control and elimination of bacteremia  Lack of mechanical tissue trauma  Reduced postoperative pain and edema  Reduced scarring and tissue shrinkage  Microsurgical capabilities  Less instruments at the site of operation  Asepsis due to non-contact tissue ablation and prevention of tumor seeding
  • 75.
    Laser Osteotomy  Experimentallaser osteotomies performed in vitro and in vivo using different wavelengths including excimer lasers, Er:YAG, CO2 and Ho:YAG lasers  The laser light emitted by Er:YAG and CO2 --- absorbed water Er:YAG laser--- absorbed by hydroxyapatite CO2 laser --- absorbed by collagen  Light microscopy, histologic sections and SEM revealed no charring, but a very thin basophilic zone next to the cut surface, while cutting the trabecular structures resulted in coagulation zone
  • 76.
    Fibromas  Fibromas areoften due to lip biting.  The soft tissue surgery can be performed using Laser HF using the fibroma removal mode (975nm, 5W, CW) without side effects or complications after surgery
  • 77.
    Clinical appearance ofa lower lip fibroma Use of Laser HF for soft tissue surgery Postsurgical view. Follow up two weeks after surgery.
  • 78.
    Mucocele  Mucoceles ofthe lip can be unroofed, then excised with gland tissue using Laser HF, using fibroma removal mode (975nm, 5W, CW).  The wound margins may be sealed with a defocused beam without side effects or complications.  Re-epithelization takes about three weeks
  • 79.
    Clinical appearance ofthe mucocele Unroofed lesion after first laser use Excision of the lesion together with adjacent salivary gland using diode laser Final postoperative view.
  • 80.
    Palatal Lesions  Lesionsof the soft palate such as traumatic fibromas in the soft palate can be treated using Laser HF, fibroma removal mode (975nm, 5W, CW).  Application of LLLT immediately after surgery may expedite healing (Acupuncture mode, 660nm, 90mW, 90s interval) without side effects or complications
  • 81.
    Clinical appearance ofthe fibroma of the soft palate Usage of diode laser for soft tissue surgical procedure Application of LLLT immediately after surgery. Follow up three weeks after surgery
  • 82.
    Epulis Fissuratum  Epulisfissuratum of the jaws can be removed using Laser HF, via a combination of Fibroma removal (975nm, 5W, CW) and Gingivectomy modes (975nm, 3W, 10ms, 1:2), followed by LLLT application immediately after the surgical procedure (Acupuncture mode, 660nm, 90mW, 90s interval).  The aPDT may also be performed (660nm, 50mW, 30s interval) without complications  Palatal fibroepithelial polyp and inflammatory papillary hyperplasia of the hard palate can be treated similarly using Laser HF using (Fibroma removal mode, 975nm, 5W, CW) in combination with loop of high frequency.  LLLT application (Acupuncture mode, 660nm, 90mW,90s interval) immediately after surgery
  • 83.
    Clinical appearance ofa maxillary epulis fissuratum Surgical procedure performed using diode laser Immediate postsurgical view. Application of the ''photosensitizer'', a coloring solution for aPDT, and photodynamic therapy using diode laser. b. Application of the diode laser.
  • 84.
    Exposure of impactedteeth  Exposure of an impacted tooth (soft tissue impaction) can be done using Laser HF, (Gingivectomy mode, 975nm, 3W, CW).  After laser incision around the impacted crown, the mucosal tissue is removed with an elevator until the underlying crown is identified
  • 85.
    Clinical view beforesurgery Incision using diode laser. Removal of the mucosal flap with an elevator. Immediate application of the orthodontic element.
  • 86.
    Crown lengthening  Crownlengthening is easily done using lasers.  After raising the mucoperiosteal flap, selective osteotomy with the surgical bur is performed.  Subsequent to the suturing and frenectomy, laser gingivectomy using LaserHF (Gingivectomy mode, 975nm, 3W, 10ms, 1:2) for the lengthening of clinical crowns can be done
  • 87.
    a. Treatment planningbefore surgery. b. Radiograph before surgery. a. Selective osteotomy after raising the mucoperiosteal flap. b. Selective osteotomy completed.
  • 88.
    a. Subsequent tothe suturing and frenectomy, gingivectomy using diode laser was performed.b. Frenectomy, gingivectomy completed.
  • 89.
    Laser Doppler Flowmetry -To monitor pulpal and gingival blood flow - To assess tooth vitality • Laser Fluorescence for detection of caries • Laser Doppler Vibrometry to measure tooth mobility. LASER DIAGNOSTICS
  • 90.
    PART OF EYE DAMAGED LASERTYPE • Corneal damage • Er Cr YSGG, Ho YAG, Er YAG, CO2 • Lens damage • Diode, Nd YAG, Ho YAG, Er Cr YSGG, Er • Aqueous damage • Ho YAG, Er Cr YSGG, Er YAG • Retinal damage • Argon, He Ne, diode, Nd YAG EYE DAMAGE
  • 91.
    315 – 400nm Eye Lens Damage 760 – 1400 nm Retinal Damage 1400 nm – 1 mm Corneal Damage
  • 92.
    • Radiation absorbedin eye lens • Effects are delayed (e.g.; cataracts). Near Ultraviolet Wavelengths (315 - 400 nm) • Radiation transmitted to retina • Overexposure --- flash blindness or retinal burns and lesions. Near Infrared (760 - 1400 nm) • Radiation transmitted to cornea. • Overexposure --corneal burns. Far Infrared (1400 nm - 1 mm)
  • 93.
    EYE PROTECTION Eye wearfor patient Safety Glasses
  • 94.
    PLUME CONTROL  Rapidrise in temperature causes cells to rupture  Release of heated plume -- particles, gases (e.g., hydrogen cyanide, benzene, and formaldehyde), tissue debris, viruses, and offensive odour  Also HPV, HIV, coagulase-negative Staphylococcus, Corynebacterium species, and Neisseria species) detected in laser plumes RECOMMENDATION:  High-filtration surgical masks,  Central room suction units and  Mechanical smoke exhaust systems (high volume laser smoke evacuation)
  • 95.
    Laser Plume FaceMask Protection from particle size less than 0.1 micron
  • 96.
    SHARPS  Scored lasertips of quartz fibers are considered sharps and need to be disposed according to standard waste disposal protocols
  • 97.
  • 98.
    HOW TO MINIMIZELASER HAZARD Engineering Control • Automatic features in built with the system to protect personals – Warning System, Interlock Administrative Control • Policies that limit exposure to laser hazards – Only for Authorized Personals Procedural Control • Standard Operating Procedure to be followed while working with lasers Beam Control • The use of beam blocks, beam tubes etc to minimize the Nominal Hazard Zone
  • 99.
  • 100.
    FIRE & EXPLOSIONHAZARD Class IV Lasers are associated with fire hazards Following things must always be kept in mind while operating such systems: • Wet or fire-retardant materials - in operative field • Use only non- combustible anesthetic agent • Nitrous Oxide supports combustion and should not be used • Avoid cleaning the tip with alcohol/spirit . Moistened gauze to be used just prior to firing • Store highly combustible or explosive materials outside • Know location and operation of the nearest fire extinguisher
  • 101.
    LASER IN FUTURE 1.Laser tooth brush : Low level laser therapy (LLLT) can be used to treat dentinal hypersensitivity
  • 102.
    2. Photobiomodulation lasertreatment --- accelerates healing time and reduces inflammation. Also can be used in treatment of herpes lesions if virus detected early. 3. Nightlase laser therapy---- reduces snoring, increase airway space, enhance quality of sleep. 4. Smoothlase laser therapy (Stealth Facelift) ---- Cosmetic enhancement of face skin using dual laser energy. Skins around mouth, nose ,chin and upper neck is tightened for youthful appearance.
  • 103.
    References •Gounder R, GounderS. Laser science and its applications in prosthetic rehabilitation. J Lasers Med Sci. 2016;7(4):209-213. doi:10.15171/jlms.2016.37. •Durrani S. Laser and it’s Application in Prosthetic Dentistry. Int J Dent Med Res 2015;1(6):183-188. •S, Misra SK, Chopra D, Sharma P. Enlightening the path of dentistry: Lasers – A brief review. Indian J Dent Sci 2018;10:184-9. •Sandesh Gosawi, Sanajay Kumar et all. Lasers in prosthodontics- a review. Journal of Evolution of Medical and Dental Sciences 2012; 1(4): 624-33. •El khourani Wadie and Pr Amal El yamani. “Lasers in Fixed Prosthodontics”. Acta Scientific Dental Sciences 3.12 (2019): 99-103.
  • 104.
    •Das Manjula etall. Lasers in Prosthodontics – Review. University J Dent Scie 2017; 3(2) : 09-12. • LJ Walsh . The current status of laser in Dentistry. Australian Dental Journal 2003 ; 48 : (3) 146-155 • Laser in Dentistry, Leo J.Miserendino/Robert M.pick, 1995 • Laser in dentistry: Dental clinic of North America Vol.44,no. 4 Oct. 2000 •Kaura S, Wangoo A, Singh R, Kaur S. Lasers in prosthodontics. Saint Int Dent J 2015;1:11-5 •Dental clinics of North America “ Lasers in Clinical dentistry”. Oct 2004. Vol 48. Issue 4 •Introduction to laser technology. –online access. • Fornaini C. Intraoral laser welding. INTECH Open Access Publisher; 2010 Aug 17.
  • 105.
    We must acceptfinite disappointment, but never Lose infinite HOPE. Dr. Martin Luther King, Jr. THANK YOU

Editor's Notes

  • #27 Wavelength from ultraviolet to the far infrared range are generally used in medical practice which ranges from 193 nm to 1060 nm
  • #32 Back-scatter of the laser beam can occur as it hits the tissue;most in short wavelengths, eg diode, Nd:YAG (≥50% back-scatter).
  • #35 temperature change, phase transfer and incident energy levels.
  • #93 *NOTE: Laser retinal injury can be severe because of the focal magnification (optical gain) of the eye which is approximately 100,000 times. This means that an irradiance of 1 mW/cm2 entering the eye will be effectively increased to 100 W/cm2 when it reaches the retina.
  • #99 Neutral Hazard Zone is the distance the beam must travel before it has diverged enough that the irradiance in the center of the beam drops below the Maximum Permissible Exposure based on animal experiments