102. Physical and Electrical Therapy in Periodontics                                     

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Review of types of lasers and  and use un periodontal therapy LANAP and photodynamic therapy
Lasers in the treatment of hypersensitivity Lasers in the treatment of periimplantitis
Cryosurgery in periodontics Electrosurgery in periodontics and compared to other modalities

 

 

 

 

 

 

What does the LASER acronym stand for? What are the most common types of lasers used in periodontics? What are the advantages and disadvantages of lasers? What role do lasers play in current periodontal therapy ?

  1. Cobb CM. Lasers in periodontics: a review of the literature. J Periodontol. 2006 Apr;77(4):545-64

  2. Pick, R., Colvard, M. Current status of lasers in soft tissue dental surgery. J Periodonto 1993;64:589-602

  3. Ishikawa I, Aoki A, Takasaki AA, Mizutani K, Sasaki KM, Izumi Y. Application of lasers in periodontics: true innovation or myth? Periodontol 2000. 2009;50:90-126.

  4. AAP statement on the efficacy of lasers in the non-surgical treatment of inflammatory periodontal disease. J Periodontol 2011:82:513-514

What is the photodynamic therapy? What is the Laser Assisted New Attachment Procedure (LANAP)? Is LANAP successful?

  1. Berakdar, et al: Comparison between scaling root planing (SRP) and SRP/photodynamic therapy: Six month study. Head Face Med 2012;8:12

  2. de Oliveira RR, Schwartz-Filho HO, Novaes AB Jr, Taba M Jr. Antimicrobial photodynamic therapy in the non-surgical treatment of aggressive periodontitis: a preliminary randomized controlled clinical study. JPeriodontol. 2007 Jun;78(6):965-73.

  3. Yukna RA, Carr RL, Evans GH. Histologic evaluation of an Nd:YAG laser-assisted new attachment procedure in humans. Int J Periodontics Restorative Dent. 2007 Dec;27(6):577-87

  4. Nevins M, Kim SW, Camelo M, Martin IS, Kim D, Nevins M. A prospective 9-month human clinical evaluation of Laser-Assisted New Attachment Procedure (LANAP) therapy. Int J Periodontics Restorative Dent. 2014 Jan-Feb;34(1):21-7.

Are lasers equally effective on hard tissue and soft tissue? What effects do lasers have on the root surface? On Implant surfaces? On calculus?

  1. Crespi R, Romanos GE, Cassinelli C, Gherlone E. Effects of Er:YAG laser and ultrasonic treatment on fibroblast attachment to root surfaces: an in vitro study. J Periodontol. 77(7):1217-22. 2006

  2. Sculean A, Schwarz F, Berakdar M, Romanos GE, Arweiler NB, Becker J. Periodontal treatment with an Er:YAG laser compared to ultrasonic instrumentation: a pilot study. J Periodontol. 75(7):966-73, 2004

  3. Crespi R, Barone A, Covani U. Er:YAG laser scaling of diseased root surfaces: a histologic study. J Periodontol. 77(2):218-22,2006

  4. Hakki SS, Berk G, Dundar N, Saglam M, Berk N. Effects of root planing procedures with hand instrument or erbium, chromium:yttrium-scandium-gallium-garnet laser irradiation on the root surfaces: a comparative scanning electron microscopy study. Lasers Med Sci. 2010 May;25(3):345-53.

  5. Fukuoka H, Daigo Y, Enoki N, Taniguchi K, Sato H. Influence of carbon dioxide laser irradiation on the healing process of extraction sockets. Acta Odontol Scand. 2010 Jan;69(1):33-40.

  6. Wilcox, C et al. Use of electrosurgery and lasers in the presence of dental implants. Int J Oral Maxillofac Implants 2001;16:578-582

  7. Galli C., eta al. The effects of Er:YAG laser treatment on titanium surface profile and osteoblastic cell activity: An in vitro study. J Periodontol 2011;82:1169-1177

  8. Romanosl G et al. OSteoblast attachment on titanium disks after laser irradiation . Int J Oral Maxillofac Implants 2006;21:232-236

  9. Krause F, Braun A, Brede O, Eberhard J, Frentzen M, Jepsen S. Evaluation of selective calculus removal by a fluorescence feedback-controlled Er:YAG laser in vitro. J Clin Periodontol. Jan;34(1):66-71. 2007
     

What is the effect of lasers in the treatment of hypersensitivity?

  1. Sgolastra F, Petrucci A, Gatto R, Monaco A. Effectiveness of laser in dentinal hypersensitivity treatment: a systematic review. J Endod. 2011 Mar;37(3):297-303. Review

  2. Kimura Y, Wilder-Smith P, Yonaga K, Matsumoto K. Treatment of dentine hypersensitivity by lasers: a review. J Clin Perio 27:715-721, 2000
     

Can LASERS be used to treat periimplantitis?

  1. Claffey N, Clarke E, Polyzois I, Renvert S. Surgical treatment of peri-implantitis. J Clin Periodontol. 2008 Sep;35(8 Suppl):316-32.

  2. Schwarz F, Sahm N, Iglhaut G, Becker J. Impact of the method of surface debridement and decontamination on the clinical outcome following combined surgical therapy of peri-implantitis: a randomized controlled clinical study. J Clin Periodontol. 2011 Mar;38(3):276-84

What are the possible applications of cryosurgery in periodontics? What are the histologic effects of cryosurgery ?

  1. Shirazi AS1, Moeintaghavi A, Khorakian F, Talebi M. Treatment of gingival physiologic pigmentation in adolescents by liquid nitrogen cryosurgery: 24-month follow-up.Int J Periodontics Restorative Dent. 2012 Aug;32(4):e142-6.

  2. Pogrel MA, Yen CK, Hansen LS. A comparison of carbon dixide laser, liquid nitrogen cryosurgery, and scalpel wounds in healing. Oral Surg Oral Med Oral Path 69:269-273, 1990.

What are the effects of electrosurgery to the periodontium? Is electrosurgery damaging to the periodontium ? How do lasers, electrosurgery, and cryosurgery compare related to periodontal treatment?

  1. Ozcelik O1, Haytac MC, Akkaya M. Iatrogenic trauma to oral tissues. J Periodontol. 2005 Oct;76(10):1793-7.

  2. Krejci R, et al. Electrosurgery - A biological approach. J Clin Periodontol 14:557 - , 1987.

  3. Sawabe M1, Aoki A, Komaki M, Iwasaki K, Ogita M, Izumi Y. Gingival tissue healing following Er:YAG laser ablation compared to electrosurgery in rats. Lasers Med Sci. 2013 Nov 16. [Epub ahead of print]
     


What does the LASER acronym stand for? What are the most common types of lasers used in periodontics? What are the advantages and disadvantages of lasers? What role do lasers play in current periodontal therapy ?

Cobb 2006: AAP review               ARTICLE


P: literature review to determine the state of the science regarding the application of lasers to common oral soft tissue problems, root surface detoxification, and the treatment of chronic periodontitis.
D:. Typically, lasers are named according to the active element that is induced to undergo the stimulated quantum transitions that, in turn, creates the energy beam. Thus, lasers commonly used in dentistry consist of a variety of wavelengths delivered as either a continuous, pulsed (gated), or running pulse wave- form, e.g., CO2, Nd:YAG, Ho:YAG, Er:YAG, Er, Cr:YSGG, Nd:YAP, GaAs (diode), and argon.

The energy emitted by a laser is essentially a light of one color (i.e., monochromatic) and, therefore, of one wavelength. The photons comprising the energy beam are emitted as a coherent (in phase), unidirectional, monochromatic light that can be collimated into an intensely focused beam that exhibits little divergence. The focused energy beam will interact with a target material by being absorbed, reflected, or scattered. In the case of biologic tissues, the laser energy is absorbed by the target surface tissues and will only exhibit scattering in cases of deep tissue penetration.
The absorbed light energy is converted to heat and constitutes a photothermal event. Depending on various parameters, the absorbed energy can result in simple warming, coagulation, or excision/incision through tissue vaporization. Variable parameters affecting energy absorption include emission wavelength, power (watts), waveform (continuous or pulsed), pulse duration, energy/pulse, energy density, duration of exposure, peak power of pulse, angulation of the energy delivery tip to the target surface, and optical properties of the tissue.
Bone is a composite tissue, having ~67% inorganic minerals (HA). By contrast, gingiva is comprised of varying densities of fibrous CT, associated ECM components, a high water content, & often exhibit melanin pigmentation. Each wavelength of laser energy is absorbed to a greater or lesser degree in water, pigment, or HA.






Pick, 1993             ARTICLE


P: To review laser physics, the types of lasers currently available for use on soft tissues,
the histological effects of lasers on oral tissues, laser safety, and the clinical applications of
lasers on oral soft tissues.
D: LASER= Light amplification by stimulated emission of radiation
All laser devices have the following components:
1) A laser medium which can be a solid, liquid, or gas. This lasing medium determines the wavelength of emitted light from the laser and the laser is classified after the lasing medium; i.e., C02 laser.
2) An optical cavity or laser tube having two mirrors, one fully reflective and the other partially transmissive which are located at either end of the optical cavity.
3) An external mechanical, chemical, or optical power source which excites or "pumps" the atoms in
the laser medium to higher energy levels. As more atoms are excited into higher energy levels, a population inversion occurs. Atoms in the excited state spontaneously emit photons of light which bounce back and forth between the two mirrors in the laser tube striking other atoms and causing more stimulated emissions. Photons of energy of the same wavelength and frequency escape through the transmissive
mirror and form the laser beam.

The energy that leaves the tube is extremely intense, directional, collimated, and monochromatic. The properties of intensity, collimation, monochromicity, and coherence distinguish laser light from that of disorganized radiant energy such as that from a light bulb. If a lens is placed in front of the laser beam, an extremely small intense beam of energy is produced which has the ability to vaporize, coagulate, and cut.

Types of Lasers
CO2


Nd:YAG


BL: Both the CO2 and the Nd:YAG lasers are ineffective in removing bone. Can be used for incisions that are made into nonkeratinized alveolar mucosa for a vertical releasing incision. There is a difference in speed between the Nd:YAG and the CO2 laser for most oral soft tissue applications such as biopsies, frenectomies, removal of large hyperplasias, coagulation of bleeders, and ablations. The CO2 unquestionably performs these procedures in less surgical time. Both the CO2 and the Nd:YAG laser have limited use in conventional flap therapy.


Ishikawa 2009            ARTICLE
Discussion: To review the application of lasers in periodontics


Advantage of lasers include hemostasis, detoxification and bactericidal effects.
The most important precaution in laser therapy is eye protection of patient, dentist and assistant. The second most important is protection from thermal injury. There is a risk of excessive tissue destruction since there is no control of the depth of ablation.
Soft tissue applications: gingival soft tissue, compared to scalpel: hemostasis and bacterial killing, no or topical anesthesia, no or few sutures needed. Anecdotally, less pain postoperatively.
Soft tissue procedures: CO2 lasers in soft tissues, is rapid and simple vaporization with strong hemostasis, clear operating field and no or few sutures, CO2 is indicated for gingival hyperplasia. Nd:YAG and Diode lasers can also cut soft tissue but have high thermal output and leave a relatively thicker coagulation area. Nd:YAG is contraindicated in management or peri-implant soft tissue because it interacts with titanium. Er:YAG has weaker hemostatic effect, but healing is relatively fast and comparable to scalpel.
Esthetic procedures: For esthetic procedures Er:YAG is indicated due to less thermal ablation. For depigmentation CO2, Nd:YAG, and Diode lasers are greatly effective, however, in thin gingiva they can cause ulcerations. Er:YAG can also be used to treat pigmentation, and metal tattoos with little recession and discomfort, especially if microscopes are used.
Nonsurgical pocket therapy: CO2 cannot be used, causes melting and carbonization of calculus, Nd:YAG cannot remove calculus either. Er:YAG and more recently Er,Cr:YSGG can easily remove calculus without thermal injury, however, in vivo study show lower calculus removal than mechanical instrumentation. CO2 carbonizes cementum and the char layer can inhibit periodontal attachment in vivo. Nd:YAG lasers causes melting, carbonization, charring and surface craters, even when it is applied parallel to root surface. These alterations are not suitable for fibroblast attachment in vitro, however, they are reversible. Diode lasers, when applied on dry or saline-moistened root surfaces have no effect, but when blood-coated specimens were used, sever damage was noted. Er:YAG lasers when used with irrigation, cause irregularities without injury, favors fibroblast attachment better than mechanical instrumentation in vitro. Lasers have been shown to decontaminate the soft tissue wall of pockets (LANAP, Yukna case series that shows regeneration on previsouly diseased root surface)

Surgical Debridement: CO2 lasers can easily achieve degranulation of bone defects. However, the same precautions of carbonizations of hard tissues. Er:YAG is also effective, some studies showed benefits to bone regeneration with Er:YAG but most show NSSD.
Osseous Surgery: Er:YAG with irrigation has been used, causes bone ablation with minimal thermal damage to adjacent tissues. CO2 has also been studied, it showed severe carbonization and melting, so did Er:YAG without irrigation. But, unlike rotary and hand instruments, lasers cut by non-contact to an unknown depth.
Implant Dentistry: Er:YAG has been used to create osteotomies for implant placement, uneventful healing observed, but results are controversial. Kesler showed a SS higher early bone-to-implant contact with Er:YAG prepared osteotomies.

Subgingival calculus detection: Diode lasers cause fluorescence in subgingival calculus. This is combined with Er:YAG and called Key Laser III™ and sold by Kavo, Germany, mainly in European countries for selective calculus removal.
Summary:
Application of lasers has been recognized as an adjunctive or alternative approach in periodontal and peri-implant therapy. Soft tissue surgery is one of the major indications of lasers. CO2, Nd:YAG, diode, Er:YAG and Er,Cr:YAG lasers are generally accepted as useful tools for these procedures. Laser treatments have been shown to be superior to conventional mechanical approaches with regards to easy ablation, decontamination and hemostasis, as well as less surgical and postoperative pain in soft tissue management. Laser or laser-assisted pocket therapy is expected to become a new technical modality in periodontics. The Er:YAG laser shows the most promise for root surface debridement, such as calculus removal and decontamination. Concerning the use of lasers for bone surgery, CO2 and Nd:YAG lasers are considered unsuitable because of carbonization and degeneration of hard tissue. Currently, the Er:YAG laser is safe and efficient for periodontal bone surgery when used concomitantly with water irrigation. Application of lasers has also been considered in implant therapy. Based on previous reports, lasers, especially the Er:YAG laser, hold promise as an alternative treatment in the treatment of peri-implantitis. Application of photodynamic therapy in the treatment of periodontitis and peri-implantitis is a novel approach. However, to date the real superiority of photodynamic therapy for clinical improvements has not been demonstrated. Further studies are encouraged to understand in more detail the effects of laser therapy.


AAP Statement 2011            ARTICLE
Purpose: To provide an evidence – based perspective on three of the purported benefits of using lasers in the non- surgical treatment of periodontal disease.
1. Sulcular and/or pocket debridement (laser curettage): Laser has little on no effect on PD reduction or AL gain when used as an adjunct to SRP. Treatment depends mainly on effective debridement of root surface and not on Sulcular epithelium removal.
2. Reduction of subgingival bacterial levels: Evidence shows lasers as a gourp to be unpredictable and inconsistent in their ability to reduce subgingival microbial loads beyond that achieved by SRP alone. This conclusion appears to apply to the used of photodynamic therapy.
3. Scaling and root planing: Erbium laser shows the greatest potential for effective root debridement (SRP). The Er:YAG laser has been shown in vitro to remove calculus and negate endotoxin. There is the potential of root damage since it is a hard tissue laser and the operator would not be able to visualize what is being lased. Although studies of its effectiveness compared to SRP alone are conflicting (some show little benefit, other show no benefit), further study is needed to determine if laser-assisted SRP has a beneficial effect.


What is the photodynamic therapy? What is the Laser Assisted New Attachment Procedure (LANAP)? Is LANAP successful?

Berakdar 2012            ARTICLE
Purpose: to examine in patients with chronic periodontitis an efficacy of the photodynamic therapy in addition to the classical treatment with SRP

Materials and methods

1) SRP (Control)
2) SRP + photodynamic therapy (PDT) (Experimental group)

Results

Conclusion


De Oliveira 2007            ARTICLE
P: To investigate the applicability of photodynamic therapy in the non-surgical treatment of aggressive periodontitis through the analysis of clinical parameters.
M&M: 10 pts b/w 18 and 35 with generalized aggressive periodontitis were treated in a split mouth design study using either photodynamic therapy (a diode laser with a wavelength of 690 and a photosensitizer) or SRP with hand instruments. PI, GI, BOP, PD, Recession, and CAL were made at baseline and 3 months using an automated probe on paired single rooted maxillary teeth.
R: For both groups, the PI sig improved at 3 months w/NSD b/w therapies. A significant reduction was also noted in GI and BOP after 3 months. Mean PD decreased in the laser group from 4.9 mm to 3.5mm, and mean CAL went from 9.93mm to 8.74 mm. In the SRP group, mean PD decreased from 4.9 mm to 4.0 mm, with mean CAL changing from 10.5 mm to 9.0 mm. There was NSD b/w groups.
D: Photodynamic therapy reduces treatment time and does not necessarily require local anesthetic. Other studies have shown bacterial destruction in a very short time period, and does not have the complication of bacterial resistance. Another advantage is limiting destruction to surrounding tissues, although the photosensitizer is effective in the surrounding epithelium and CT, which is crucial for species like Aa which are capable of soft tissue invasion. One of the notable drawbacks to this therapy is leaving residual calculus.
BL: In pts with generalized aggressive perio, Photodynamic therapy showed results comparable to SRP.
Cr: No antibiotics were used, which is often the case with nonsurgical treatment of aggressive periodontitis.


Yukna, 2007            ARTICLE
P:  to describe histologic results in humans following Nd:YAG* laser-associated-attachment-procedure (LANAP) for the treatment of periodontal disease
M&M:  6 pts (3M/3F), 26 to 54 years old, six pairs of single rooted teeth with moderate to severe periodontitis, PD and clinical probing attachment loss of 5 – 9 mm, BOP and evident subgingival calculus, preoperatively occlusal adjustment/odontoplasty, study teeth were splinted to adjacent teeth with Ribbond, SC/RP were performed in same segment (except treatment teeth), general supragingival prophylaxis, documentation with photographs, radiographs with stent and grind, measurements mod. GI, PI and clinical mobility.  Notch placed apical extent of calculus, all teeth SC/RP with US and HI, one of each pair of teeth received tx of inner pocket with Nd:YAG laser to remove pocket epithelium , second time lased to seal the pocket. After 3 month all treated teeth were removed en bloc for histologic evaluation
Results:  all test teeth (LANAP treated) showed greater PD reduction (4.7mm vs. 3.7mm) and clinical attachment level gains (4.2mm vs. 2.4mm) then control teeth. All test teeth showed new cementum, new CT attachment in and occasionally coronal to the notch, 5/6 control teeth had a long JE with no evidence of new attachment or regeneration. No evidence of any adverse histologic changes around LANAP specimens. 
BL:  these cases support the concept that LANAP can be associated with cementum mediated new CT attachment and apparent periodontal regeneration of diseased root surfaces in humans.
Note: LANAP is a combined therapy using a patented protocol that included: occlusal adjustment, splinting when needed, systemic and topical antibiotics, laser for surgical pocketing removal, SC/RP, laser use for tissue stabilization (welding) against the tooth surface with a fibrin clot.
*neodymium:yttrium-aluminum-garnet


Nevins, 2014            ARTICLE
Background: LANAP therapy was introduced 15 years ago, to treat advance periodontal disease w/o sx therapy. Histologic reports had provided evidence of new attachment after it use. No published studies of the clinical efficacy evidence prior to this study.
P: Prospective study to clinically evaluate the Laser Assisted New Attachment Procedure (LANAP) therapy.
M&M: 8 pts. At least 1 tooth with 7mm PD indicated for extraction and radiographic suggestion of a 4mm infrabony defect. One examiner performed full mouth measurements. Surgery: 1) Local anesthesia. 2) Laser periodontal surgical therapy with Nd:YAG (Neodymium: Yttrium Aluminum-Garnet) setting of: 4.0W,100- μs pulse duration, and 20 Hz. It was passed from the gingival margin to the base of the pocket parallel to the root surface and move laterally and apically to remove the diseased epithelium. 3) Aggressive SRP with piezo-ultrasonic. 4) Second pass with the laser with a setting of 4.0W, 650-μs pulse duration, and 20 Hz. Moved from the apical to the gingival margin. 5) Occlusal adjustment if needed, splinting, 0.12% chlorhexidine for 4 weeks post-sx. Area was cleaned 7,14,28,42 and 56 days with a chlorhexidine-soaked gauze and prophylaxis at 2.5, 4, 5.5, 7 and 8.5 months. 6) At 9 months final measurements were taken.
R: Initial dentinal sensitivity, then came back to normal. PD reduction from 4.62 ± 2.29mm to 3.14 ± 1.48mm. 73% sites decreased PD, 21% no change and 6% increased. CAL decreased from 5.58 ± 2.76mm to 4.66 ± 2.10. 58% had gain attachment, 24% no change 18% lost. Recession increased from 0.86mm ± 1.31mm to 1.52 ±1.62. Sites with >4.88mm PD are more likely to gain attachment level.
BL: Reduction of PD and CAL gain can be expected after this less invasive tx.
Cr: Sponsored by Millenium Dental Technologies, no control groups.

Are lasers equally effective on hard tissue and soft tissue? What effects do lasers have on the root surface? On Implant surfaces? On calculus?


Crespi 2006            ARTICLE
P: Analyze the effects of Er:YAG laser and ultrasonic treatment on fibroblast attachment to periodontally diseased root surfaces.
M&M: 30 patients (20 females and 10 males, max age 45), one study tooth per patient. Study teeth were single rooted periodontally involved teeth. Pt’s who had antibiotic treatment in the last 4 months or SRP in the last 6 months were excluded. Coronal section was performed 1 mm below the CEJ and an apical section was performed 4mm from the root apex. The tooth was then sectioned bucco-lingually and the pulp was removed to avoid contamination. These 60 specimens were divided into 3 groups:
1) Group A (n=10): control group rinsed with sterile saline.
2) Group B (n=25): specimens were scaled with ultrasonic instruments for 60 seconds until all visible calculus was removed.
3) Group C (n=25): specimens were treated with Er:YAG laser system at 160 mJ/pulse at 10 Hz equivalent to the energy densities of 94 J/cm² per pulse for 40 seconds.
Treated root specimens were placed in petri dishes with 2 ml antibiotic-antimycotic solution for one hour. They were then thoroughly rinsed and placed into well plates and covered with 2 ml fibroblast suspension. They were then cultured for 3 days. After incubation, specimens were rinsed, fixed, and dehydrated. Then they were coated in gold sputter three times and examined using a scanning electron microscope.
R: Cell distribution: Fibroblast morphology was different between the three groups. The untreated control root surfaces were incompatible with cellular development and distribution. The ultrasonic group had scattered flat and healthy fibroblasts. The laser treated group were covered by a confluent monolayer of flat, spindle-shaped fibroblasts which were firmly attached to root surfaces.
Cell counting: Control and ultrasonic surfaces exhibited a significantly lower number of attached cells compared to laser-treated ones. Cell density was 3,720 ± 316 cells/mm² for laser treated surfaces, 658 ± 140 cells/mm² for the ultrasonic group, and 130 ± 80 cells/mm² for the control. Differences between all groups were statistically significant (P<0.0001).
BL: The Er:YAG laser induces a homogenous roughness to root surfaces which enhances adhesion and proliferation of fibroblasts, more so than ultrasonically treated specimens. The Er:YAG group had an increase in fibroblast attachment. Cell attachment is impaired by the smear layer obtained during ultrasonic instrumentation. More studies are needed to confirm that complete elimination of the smear layer results in improved fibroblast attachment.
CR- what effect did 2 ml antibiotic-antimycotic solution for one hour have?


Sculean 2004            ARTICLE
P: To compare the effectiveness of an Er:YAG laser to ultrasonic scaling for non-surgical periodontal treatment.
M&M: Twenty healthy patients (29-62 years) were included. Selection criteria: 1) no periodontal treatment within the last 12 months 2) no systemic disease 3)non pregnant 4) no use of antibiotics for 6 months prior to treatment and 5) good OH. The study used a split-mouth design, with half of the mouth receiving US scaling and the other side receiving Er:YAG laser (combined with a calculus detection system with fluorescence) for sub-gingival debridement. Only sites with 4mm PDs or greater were instrumented. Treatment was performed within 24 hrs. Supra-g debridement was performed at baseline and at 2, 4, 6, 8, 10, 12, 16, 20, and 24 weeks after treatment. Clinical parameters (PD, PI, recession, CAL and BOP) were evaluated at baseline and 3,6 months after treatment.
R: Post-op healing was uneventful in all cases. At baseline examination there were no SSD between all investigated parameters. The results of BOP, CAL, PD, and recession were almost identical between groups at 3 and 6 months. There was NSSD between groups in any parameter. Initially deeper pockets (>5mm) showed the greatest changes in the PD, CAL and recession. Both groups required about the same time to perform the therapy.





BL: Ultrasonic scaling and the Er:YAG laser are equally effective in providing non-surgical therapy of periodontal disease.


Crespi, 2006              ARTICLE
P: To study the effect of Er:YAG laser on diseased, calculus-covered root surfaces in periodontal pockets in vivo comparing to conventional mechanical debridement
M+M: 40 periodontally involved teeth that were scheduled for extraction were assigned to two groups. Group A: Hand instrumentation with Gracey curets (control) and Group B: Er:YAG laser at 160 mJ/pulse at 10 Hz w/ a chisel shaped tip applying at the bottom of periodontal pockets with apico-coronal movements in a parallel direction along the root surface with an angulation of 30 degrees. All of the teeth were immediately extracted after instrumentation, and histologic examination was performed
R:

Parameters

Hand instrumentation

Laser

Root surfaces

Smooth

Rough

Bacterial elimination

Partially

Completely

Removal of cementum layer

Complete

Partial

Dentin layer

Open dentinal tubule and scratches

No alteration

Remark


No major thermal change. No cracking or carbonization


BL: Er:YAG laser at 160mJ/10Hz in vivo achieves complete plaque and calculus removal, and provides a rough surface morphology.

Hakki 2010,             No ARTICLE
P: To investigate the efficiency of hand instrumentation and laser irradiation on calculus removal from the root surfaces in vitro.
M&M: 32 human teeth with calculus on their root surface and which had been extracted for periodontal reasons, with no caries, fillings, fractures or endodontic treatment were used. The root surfaces of single-rooted teeth were treated by different methods, including: 1) hand instruments, 2) hand instruments with tetracycline hydrochloride (Tet+HCL), 3) Er,Cr:YSGG laser irradiation setting I (short pulse), 4) Er,Cr:YSGG laser irradiation setting II (long pulse). Three premolar teeth extracted for orthodontic reasons served as controls. The morphology of the root surfaces was evaluated by light and scanning electron microscopy (SEM). Also, energy dispersive X-ray analysis was used to compare the mineral content of the root surfaces treated with hand instrumentation and laser. Calcium and phosphate minerals were determined in the root surface and Ca/P ratios were calculated.
R: Light microscopy and SEM showed that all treatment could remove dental calculus efficiently. The surface in the laser groups was rougher than in the groups treated with hand instruments. However, surface irregularities and smear layer were observed in the hand instrumentation group, that could be disadvantageous in providing a good root structure to form periodontal attachment. Moreover, the roughness was greater in the long-pulse setting than in the short-pulse setting. Decreased phosphate (P) levels and increased calcium (Ca) levels were noted in all groups versus healthy control. Increased Ca/P ratio was observed in all groups. The Ca/P ratio of Laser I group was closer to the control group, which had healthy teeth. The ratios of the hand instrumentation group were higher than those of the control and laser groups as well.
BL: Laser procedures, when used in appropriate settings are capable of performing scaling and root planing in the treatment of periodontitis. However, additional in vitro studies are necessary to clarify the success of laser in periodontal treatment.


Fukuoka 2011            ARTICLE
Purpose: To investigate the effect of CO2 laser irradiation on the extraction socket healing process in rats, particularly regarding trabecular changes and the appearance of myofibroblasts.
Materials and methods: After general anesthesia in 5 weeks old rats one molar was extracted while avoiding injuring the alveolar bone. In the non-irradiation (control) group hemostasis was achieved and wound was disinfected with 0.025% benzalkonium chloride solution 1 day after the extraction. In the CO2 laser irradiation group, after extraction hemostasis was not applied immediately but laser irradiation was applied to coagulate blood and prevent the loss of blood clots. The wound was disinfected one day after extraction and treated with laser again. Animals were sacrificed at 6 hours, 3, 7 or 21 days and extraction socket with surrounding tissue was excised and biopsy and immunohistological observation were performed.
Results: Extraction sockets were filled with blood clot in both groups after 6h. A carbonized layer was present on the surface of the irradiation group.
At Day 3 the sockets of the irradiation was group were filled with blood clots and many osteoclasts were present on the bony walls, while few osteoclasts were present on the control group and blood clots were present only in the center of them.
On Day 7 on the control group granulation tissue accompanied by mild inflammatory cell infiltration had was present in the surface layer and surface was covered with epithelium. Bone resorption and bone formation were present. In the test group carbonized surface layer disappeared, no osteoclasts were noted and marked bone formation.
On Day 21 sockets in both groups were filled with bone, the alveolar crest was concave in the control group, whereas trabeculae were dense and the alveolar crest was flat in the test group.
Fewer myofibroblasts were present in the test group comparing to controls at Days 3 and 7.
Osteomorphometry showed that in Day 21 the alveolar height was significantly higher in the irradiation group.
Conclusion: The rapid bone resorption and new bone formation on the surface layer over the middle layer and the appearence of fewer myofibrobalst in the surface layer may have been the effects of CO2 irradiation.
CO2 laser irradiation promotes healing of tooth extraction sockets.

Wilcox 2001            ARTICLE
Purpose: to measure and compare the temperature effects of incidental contact of a dental implant by 1) Conventional (Unipolar) electrosurgery, 2) Bipolar electrosurgery and 3) Laser beam.

Materials and methods:

Results

Conclusion



Galli 2011             ARTICLE
Background: Laser light has been proposed as a tool to decontaminate the surface of endosseous implants.

P: The goal of this study is to investigate osteoblast growth and differentiation on three commercially available surfaces untreated or after irradiation by Er:YAG laser at two levels: 150 and 200 mJ/pulse at 10 Hz.
M&M: Human osteoblastic Saos-2 cells were plated on machined, sandblasted and acid-etched titanium, or titanium plasma-sprayed disks. The effects of lasing were observed with a scanning electronic microscope, and cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The production of the osteoblast-specific protein osteocalcin and of osteoprotegerin in the supernatants by immunoenzymatic assays was also measured.
R: No visible changes were observed on machined or titanium plasma-sprayed disk samples at the tested levels. Titanium peaks on sandblasted and acid-etched titanium disks appeared fused as a consequence of laser irradiation. Cell proliferation was slower on irradiated titanium at both intensities on all the surfaces. Cell differentiation, as assessed by osteocalcin production, was unaffected by laser treatment, whereas the production of osteoprotegerin was decreased on all the surfaces irradiated at the intensity of 200 mJ/10Hz.
C: Results indicate that Er:YAG laser can alter the surface profile of titanium implants and these changes may negatively affect the viability and the activity of osteoblastic cells. Therefore, Er:YAG lasers should be used with caution on titanium surfaces.


Romanos 2006             ARTICLE
P: Osteoblast attachment on titanium surfaces is necessary to achieve new bone formation and osseointegration. The purpose of this study was to examine osteoblast attachment on irradiated titanium disks using electrom microscopy analysis.
M&M: 4 different types of titanium disks were used: Machined, hydroxyapatite (HA)-coated, sandblasted, and titanium plasma-sprayed (TPS) surfaces. The disks were divided into 3 groups based on their surface pattern and the laser used. They were irradiated with either a carbon dioxide (CO2) (Group1) or an Er,Cr:YSGG laser (Group2), and a control group of nonirradiated disks (Group 3). Osteoblast cultures were cultivated on the titanium disks and examined with scanning electron microscopy
R: All examined Ti surfaces were colonized well by osteoblasts. However, the machined group, the cellular density was higher in the laser-irradiated than in the nonirradiated specimens, b/c of the cleaner effect on superficial layers by the laser.
The lubricating fluids used in machined tools present on surfaces of this type of disk prevent cell adhesion and spreading on surfaces. Laser light eliminates these fluids and facilitates cell adhesion. The cell morphology presented on machined surfaces was typically flat. The other 3 disk surface types presented cells with pseudopodia, which is a feature of cell maturation.
BL: osteoblasts could be grown on all of the surfaces. Pseudopodia and a spread of cells demonstrated maturation were observed on the lased irradiated titanium disks. The date show that laser irradiation of titanium surfaces may promote osteoblast attachment and further bone formation.


Krause, 2007            ARTICLE
Background: The use of Er: YAG laser is controlled by a stronger fluorescence signal from the root surface with subgingival calculus than from the cementum. It is induced by a red-infrared diagnostic diose laser.
P: In vitro study to evaluate the removal of subgingival calculus and dental hard tissues depending on the threshold level of a fluorescence feedback-controlled Er:YAG laser.
M&M: Twenty extracted teeth with calculus on the root surface were treated with an Er:YAG laser. The periodontal hand piece (No.2061, KaVo, Biberach, Germany) and a novel designed chisel-shaped glass fiber application tip (size 0.4 x 1.65mm, transmission factor: 0.81) were used to guide the laser beam onto the root surface under water irrigation (1ml/min). Laser parameters were set at 140mJ/ pulse with a repetition rate of 10 Hz.
The respective energy density at the fibre tip was 17.2mJ/cm2. The laser was equipped with a laser fluorescence feedback system. The laser light of an InGaAsP diode laser with a wavelength of 655 nm (red light) is transported through a fibre bundle to the tip of the hand piece within a central fiber. Additional surrounding fibers are arranged around this central fibre that collects the fluorescent light emitted from the irradiated tissue. The laser induced fluorescence of the root surface is given in relative units from 0 to 99 and used to control the therapeutic irradiation by turning on the Er:YAG laser if the fluorescence value is above a preselected threshold level. If the fluorescence is below this value, the laser does not emit. For the present study, the evaluated threshold levels of the fluorescence feedback system were 5, 4, 3, 2 and 1[U]. Areas of residual calculus (RC) were evaluated using a surface analysis software. Loss of cement layer and dentin exposure was assessed by histomorphometric analysis, using the opposite untreated side as control.
R: Using a threshold value of 5 [U], the median amount of RC was 11% (0–78%). By lowering the threshold levels, the amount of RC decreased [level 1 [U]: 0% (0–26%)]. The laser-treated root surfaces revealed a statistically significant reduction of the cementum thickness [median: 80 µm (0–250)] compared with the non-treated opposite side of the root surface [median: 90 µm (30–250)]. No carbonization indicating termal damage, nor craters were observed.
BL: The amount of residual calculus depends on the threshold, putting it on a threshold of less than 5, leaves little residual calculus without removing significant cementum removal.


What is the effect of lasers in the treatment of hypersensitivity?

Sgolastra 2011            ARTICLE
P: To perform a systematic review to address the clinical effects of laser application compared with placebo in the treatment of dentinal hypersensitivity (DH) and to survey literature related to the safety of laser applications.
M&M: A thorough literature search with strict inclusion and exclusion criteria was performed with electronic databases (MEDLINE, Science Direct, Cochrane Clinical Trial Register, ISI Web of Science, etc) and by hand. The goal was to identify all randomized, placebo-controlled clinical trials that have assessed the effectiveness of laser in DH reduction compared with placebo laser.
R: A total of 18,661 potentially relevant titles and abstracts were found during the electronic and manual searches. Finally, a total of 3 studies fulfilled the required selection criteria and were included in the review.
1st study (Birang et al): compared the effects of Nd:YAG (w/o coolant), Er:YAG (w/ coolant) and placebo lasers on DH treatment. Pain was reduced in 91%, 62% and 28% of patients in the Nd:YAG, Er:YAG and placebo control groups respectively. However no statistical comparison between the groups was performed and no evidence was provided that any treatment was more efficient than others.
2nd study (Lier et al): compared the results by using Nd:YAG laser treatment and placebo laser and found no significant differences.
3rd study (Vieira et al): compared GaAIAs treatment with a placebo oxalate gel, and placebo oxalate with a placebo laser in split-mouth design. There was no SSD in hypersensitivity reduction.
BL: All three studies reported a statistically significant reduction in dental sensitivity until the end of the follow-up period in both the treated and placebo groups. Although laser treatment appeared to reduce dentin hypersensitivity, evidence for this effectiveness is weak, and placebo effect must be considered. At the reported wavelengths and energy settings, no pulp damages or major adverse effects were reported.


Kimura, 2000.             ARTICLE
P: Summarize laser applications for the treatment of dentin hypersensitivity
Disc: The lasers used for the treatment of dentine hypersensitivity are divided into two groups: 1) low output power [helium-neon (He-Ne) and gallium/aluminum/arsenide (GaAlAs)] and 2) middle output power (Nd:YAG and CO2).
He-Ne: irradiation modes were two types: pulsed and continuous, treatment effectiveness rate ranged from 5.2-100%. Mechanism involved is mostly unknown, most possibly affects electric activity (healthy nerve increase by 33%). It has a long-lasting effect (increase in the size of nerves action potential for more than eight months after cessation of irradiation). No damage to enamel or dentin.
GaAlAs (diode): Treatment effectiveness ranged from 85-100% (780 nm), 30-100% (830 nm), and 73% (900 nm), no damage to enamel or dentin. Analgesia thought to be related to depressed nerve transmission.
Nd:YAG: Treatment effectiveness ranged from 52-100%, use of black ink as absorption enhancer is recommended to prevent deep penetration of the Nd:YAG laser beam through the enamel and dentin and excessive effects in the pulp. Sealing depth of dentinal tubules is <4µm (30 mJ/pulse and 10 pps). The mechanism of actions is thought to be the laser-induced occlusion or narrowing of dentinal tubules as well as direct nerve analgesia.
CO2: effectiveness 59.8-100%. Mechanism of action includes occlusion or narrowing of dentinal tubules. There have been no reports on nerve analgesia by CO2 laser irradiation. CO2 laser may also cause dentinal dessication, sealing depth is 2-8 µm (.3W for .1s).
Combination of Laser treatment with fluorides: GaAlAs with fluoride increased effectiveness more than 20% (Lin 1994). Nd:YAG followed by NaFl occluded most dentinal tubules (Lan 1999).
In the use of laser in vivo, thermal effects on pulpal tissues are of concern. Previous studies have shown that healthy pulp is not damaged thermally if the laser is used at a correct parameter so that the temp rise remains below 5ºC (Zach 1965). Recurrence of hypersensitivity: He-Ne—7.4-66%, GaAlAs—6-75%, Nd:YAG—34%, CO2—50%. The mechanism of recurrence is unknown.
BL: The mechanism in laser treatment of dentin hypersensitivity is relatively unknown. These require clarification for safe, effective treatment. There is some evidence lasers may provide an efficient mechanism for hypersensitivity but may not be effective in severe cases.


Can LASERS be used to treat periimplantitis?

Claffey, 2008             ARTICLE
P: To review the literature on surgical treatment of peri-implantitis.
M+M: A search of PubMed from 1990 to September 2007 was carried out using the terms periimplantitis, peri-implant defect, implant treatment, peri-implantitis infection, peri-implantitis treatment, treatment peri-implant defect, periimplantitis, periimplant defect, periimplantitis infection, periimplantitis treatment, and treatment periimplant defect. Hand search also conducted. A total of 43 studies were selected for the review. Only 13 of these were studies in humans and only one study directly addressed disease resolution.
R: In animal studies:

In human studies:

D: Author questions the effectiveness of ligature induction of peri-implantitis and the relative similarity of this induced lesion to naturally occurring peri-implantitis in humans.
BL: The available evidence for surgical treatment of peri-implantitis is very limited.


Schwarz 2011            ARTICLE
P: To study the impact of two surface debridement/decontamination (DD) methods on the clinical outcomes of combined surgical tx of peri-implantitis.
M&M: 32 pts with a total of 38 implants that suffered moderate to advanced peri-implantitis defects were included. All implants received non-sx instrumentation using plastic curettes and were irrigated with 0.2% CHX. At 2 weeks after initial therapy, all pts were treated with access flap sx, granulation tissue removal, and implantoplasty at both buccally and supracrestally exposed implant surfaces. The remaining intra-bony aspects were randomly assigned to either Er:YAG laster (ERL) or curettes + cotton pellets + sterile saline (CPS). In both groups the sites were grafted with Bio-Oss and a collagen membrane (BioGide). Clinical and xray records were recorded at baseline and 6 months after tx. Most of the defects were circumferential and had a PD > 6mm with and intrabony component of > 3mm. All pts had good OH, no evidence of occlusal overload, 2mm KG (flap management), and were systemically healthy. Hollow cylinder implants were excluded (more than 10 different types of implants were grafted). The number of smokers was comparable in both groups.
R: 30 pts completed the study (2 dropped out because of personal reasons). There were no post-op complications during the wound healing in either of the groups. After 10-14 days of healing there was a degradation of the CM and there was almost complete soft tissue coverage. There was NSSD between groups in BOP, PI, CAL, PD or gingival recession. Both groups had almost equal PD changes at the buccal and lingual. While all groups in the CPS groups revealed a CAL gain of at least 1mm, there were two pts in the ERL groups that had a CALoss. 40% of the CPS pts had a CAL gain of 2mm and a CAL gain of 3 or 4 mm was observed in 5 other pts in the group. In the ERL group, 47% had a CAL gain of 1mm and 3 pts had a CAL gain of 3 or 4 mm. At 6 months, x-ray analysis revealed a decrease translucency in the former peri-implant defect area for 15 sites in the CPS group and 14 sites in the ERL group (total of 29/30 sites).
BL: There is no significant difference between using an Er:YAG laser and CPS in the clinical outcome following grafting of peri-implant defects.


What are the possible applications of cryosurgery in periodontics? What are the histologic effects of cryosurgery ?

Shirazi 2012            ARTICLE
Background: Cryosurgery does not require sutures or surgical packing and is associated with no bleeding during or after treatment, no surgical defects, minimal scar formation, no risk of secondary infection and minimal damage to the adjacent tissues.
Purpose: To evaluate the effect of cryosurgery with liquid nitrogen on the treatment of gingival pigmentation in adolescents.
Materials and methods: 15 adolescent patients (9 girls, 6 boys 11-14 years of age). After local anesthesia with lidocaine spray 10%, the pigmented areas were divided in 2-cm segments with each segment treated separately. Liquid nitrogen was applied with a cotton swab with a forward and backward rolling technique. Freezing appearance was observed for 20 sec after each application and this procedure was repeated 3 times for every segment. Same course of treatment was repeated after 2 weeks. Standard digital photos were taken pre-op and 3,12 and 24 months post-op and analyzed using an image-analyzing software by a blinded examiner and statistical analysis was performed.
Results: No bleeding or pain occurred in any patient during treatment and minimal reddish erythema was observed after cryosurgery. After 2 weeks gingival color was ideal for all patients. No post-op scar formation, pain or other complication. 4 patients did not return for the 24-month recall. There was some recurrence after 12 months compared to 3 months but not statistically significant. All patients were satisfied with the esthetics at 24 months.
Conclusion: Treatment with liquid nitrogen cryosurgery for PG removal in adolescents is a successful and inexpensive method that requires less equipment, no anesthesia or periodontal dressing and no pain or bleeding is observed.
Mild but not significant relapse was observed after one year.

Pogrel et al., 1990            ARTICLE
Purpose: To compare the CO2 laser, liquid nitrogen cryosurgery, & scalpel excision for speed and mode of healing of the wounds created on the shaved abdomen of rats.
Materials and methods:

Results:

BL: at 2 weeks, there was no difference clinically or histologically w/ the healing of laser or scalpel wounds. Cryowounds heal slower than either laser or scalpel wounds (and it is the least predictable technique). Lasers heal quicker initially and w/ less inflammation probably due to the sealing of blood and lymph vessels.


What are the effects of electrosurgery to the periodontium? Is electrosurgery damaging to the periodontium ? How do lasers, electrosurgery, and cryosurgery compare related to periodontal treatment?

Ozcelik 2005             ARTICLE
P: To report the diagnosis and management of thermal, chemical, and physical traumas of iatrogenic origin presented for 13 cases, which had been referred to the periodontology departments of Ankara University and Cukurova University between 1999 and 2004.
Discussion: Iatrogenic trauma can be defined as any trauma that has been induced by the dentist’s activity, manner, or therapy, and this term is usually used for an infection or other complications of treatment. During dental and periodontal treatments, numerous instruments (i.e., rotary or vibrating handpieces, electrosurgical units, and lasers), chemical substances (i.e., drugs, endodontic materials, and retraction agents), and physical appliances (partial dentures and orthodontic appliances) come in contact with the oral cavity, and improper use or application of these may result in traumatic gingival lesions. While, in most cases, the elimination of the offending agent and symptomatic therapy were sufficient, in severe cases, or when the injury resulted in permanent defects, periodontal surgery and regenerative therapy may be necessary. Although “To err is
Human”, careful practice is very important for the principle ‘‘Primum non nocere’’ (First do no harm)


Krejci 1987             ARTICLE
P: To review controlled clinical studies regarding the response of dental tissues to electrosurgical procedures and provide clinical guidelines for its use.
Discussion:
Controlled studies indicate that lateral heat is produced during the use of electrosurgery and that this heat is capable of causing changes in epithelium, connective tissue, bone, cementum and periodontal attachment. Instrumentation variables (type of waveform, size of electrode, time required for incision, energy produced at operating tip) control the amount of lateral heat produced.
Clinical guidelines:
1. Incision with electrosurgery should be with a high frequency unit tuned to optimal power output and set to generate a fully rectified, filtered waveform.
2. The smallest possible electrode should be used to accomplish the incision.
3. Electrosurgical incisions should be made at a minimum rate of 7 mm/second.
4. A cooling period of 8 sec should be allowed between consecutive incisions with a needle electrode at the same surgical site. The period should be doubled to15 sec for loop electrodes.
5. Histologic healing when a well-controlled electrosurgical incision is compared to an incision from a surgical blade varies, but a comparable final clinical healing response is usually seen. When using electrosurgical incision for troughing or excision of the gingival crevice, some increased recession should be expected
6. Avoid contact of activated electrosurgery electrode with cementum in regions where connective tissue reattachment is desired.
7. Intermittent contact of an active electrode delivering a well-controlled current to alveolar bone will initiate only slight osseous remodeling which will not result in clinical changes. However prolonged exposure may result in loss of supporting structures.
8. Contact of an active electrosurgery electrode with metallic restorations should be limited to periods less than 0.4s.Longer periods of contact may cause pulpal necrosis.
9. Electrosurgery may be used effectively for pulpotomies.
10. Use of electrosurgery for hemorrhage control should only be attempted after all other hemostatic methods. When used, delayed healing should be expected.
11. Electrosurgery may be used safely and conveniently to excise inflammatory papillary hyperplasia.

 
Sawabe, 2013            ARTICLE
Background: Er:YAG (Erbium-doped yttrium aluminum garnet) is use with less termal damage for periodontal soft and hard tissues treatment. The Electrosurgery (ElS) is used for soft tissue tx with more termal damage. Heat shock protein (Hsps), play an important role in the recovery of cells from injuries. Hsps 72/73 are produced when tissue damage had occur, prevent proteolytic degradation (cellular response to heat). Hsps 47 support maturation of collagen, it increases when Type I collagen production increases. Proliferating cell nuclear antigen (PCNA) indicates the progression of re-ephitelialization.
P: To compare the gingival tissue healing after Er:YAG (ErL) gingival ablasion to ElS (electrosurgery).
M&M: 28 rats. Gingival defects in the mesial surface (2mm BL x 1.5MD x 1mm depth) were created by ablation with ErL irradiation or ElS. Rats were sacrificed before, immediate after, 6h, 1,3,6 days after irradiation. Chronological changes in wound healing were evaluated by histolgical, histometrical and immunohistochemical analyses.
R: ErL showed less termal damage compare to ElS. Post op tissue destruction continued with Els due to termal damage. ErL site showed limited degradation and defects were re-epithelialized earlier (3d post op). ElS showed ulcer formation with pseudomembrane at day 3, re-ephitelization was at 6 day. At day 10 both had similar wound healing wo inflammation. Production of Hsps 72/73 and Hsps 47 was slightly observed near wound in ErL sites and abundant in remote sites in ElS. PCNA persisted longer in the Els than in the ErL sites.
BL:ErL results in faster and more favorable gingival wound healing compared to ElS.