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Laser Application in Periodontics

Non-surgical Periodontal Therapy increase (16). In addition, it has been shown that the
other member of the Erbium family (Er, Cr: YSGG)
Dental plaque is known as the principal etiologic has an intense bactericidal effect on the putative
factor for the inflammatory periodontal disease; periodontal pathogens, such as P. gingivalis and A.
therefore, it is evident that treatment of the disease actinomycetemcomitans (17). Selective removal of
is dependent upon how much the plaque and its supra-gingival and sub-gingival calculus and dental
retentive factors are being removed. Traditional plaque without ablating underlying hard tissue with
mechanical therapy using hand instruments have frequency doubled Alexandrite laser (337 nm) is a
shown limitation in accessing the dental biofilm and promising application that needs further studies (18).
calculus, because of their bulk and shape. Lasers Periodontal inflammation and congestion provide
have been proposed to solve this limitation as the an environment that is ideal for soft lasers such
beam can reach the deepest pockets and grooves. as argon that reduces bacterial load and coagulate
Archive of SID
The advantage of the laser in treating inflammatory since the tissues are hemoglobin pigmented and
conditions like periodontitis has been also attributed full of interstitial water.
to their host immuno-modulatory effects. All lasers
have thermal effects. Many periodontopathogens Periodontal Surgery
are susceptible to this thermal range as research
has shown that they are deactivated in 50 c° (6). Lasers are beneficial in reducing traditional
Laser mediated coagulation and inflamed tissue surgical problems such as bleeding, reduced
removal takes place in 60 c° (7). Lasers offer clear vision, pain, scarring, suturing, bacteremia, long
field views in periodontal surgeries and sub-gingival healing period and wound contraction. They will
scaling and curettage that are advantageous over also result in higher patient acceptance, since no
the conventional treatments. Patients are also more or little anesthesia is required. Periodontal surgery
comfortable with intermittent laser activation sound can be divided to soft surgery and simultaneous
rather than high-pitch sound of ultrasonic devices. soft and hard surgery. Potential bone damage has
Pain is lesser in laser application and the need for been always a concern in periodontal surgery
anesthesia is reduced in procedures such as sub- using lasers. CO , diode, and ND:YAG are
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gingival scaling (4,8,9). Photodynamic therapy is traditionally known as soft tissue laser since their
another important application of a low power laser deep penetration makes them ideal for applications
that enables the laser to indirectly decontaminate such as frenectomy, frenotomy, gingival curettage,
the periodontal pocket by activation of a photo- depigmentation, aphtus treatment and leukoplakia
sensitizer agent, thus potentiating the bactericidal management Figures 1.
effect of laser. Soft tissue thermolysis and bacterial CO laser have been used successfully for
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decontamination can be done by a variety of lasers gingivectomy and plastic reshaping of the gingiva.
such as argon (10) (488 nm, 514 nm), diode laser It has been shown that application of the CO
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(11) (800-830 nm, 980 nm) and Nd: YAG (12-14) impedes pocket epithelium growth considerably
(1064 nm), but these lasers are unsuitable for calculus more, compared to the control group. Crespi et al.
removal because of low surface thermal absorption. showed that CO laser is enable to successfully
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Erbium family lasers including Er:YAG and Erbium- condition the root surface (19).
Chromium doped: Yittrium-Selenium-Gallium-Garnet Hard tissue lasers can be applied to both hard
(Er, Cr: YSGG) have shown very promising results and soft tissues. In one study, using Fourier
for scaling, since they are capable to ablate both Transformation Infrared Spectra it was shown that
hard and soft tissues (4). In an interesting research, toxic byproducts are produced after application of
Schwartz et al have shown that clinical parameters Er: YAG laser without water coolant (20) and CO
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of periodontitis have improved significantly after laser irradiation (21,22) that results in delayed
a year in both groups treated either with Er: YAG healing (3).
laser alone, or combined with manual scaling and A key factor in determining how the laser will
root planning without significant differences (15). interact with the underlying tissues is the depth
Aoki has shown that subgingival calculus removal by of penetration. Some lasers penetrate deeply and
Er: YAG is not associated with root surface thermal the thermal effects are seen in deep tissues while

28 Journal of Lasers in Medical Sciences Volume 3 Number 1 Winter 2012
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