The Use Of Lasers in Nonsurgical Periodontal Therapy
GILAXIA/ ISTOCK/GETTY IMAGES PLUS
The efficacy of this technology as an adjunctive treatment for periodontitis and peri-implant diseases remains controversial.
By Denise M. Bowen, RDH, MS
After reading this course, the participant should be able to:
1. List the uses for each laser technology in periodontal therapy.
2. Discuss the evidence regarding laser use as an adjunct to scaling and root planing.
3. Describe the effectiveness of photodynamic therapy used for antimicrobial purposes in periodontal treatment.
4. Explain the ethical and legal considerations related to dental hygienists' use of lasers.
The objectives of nonsurgical periodontal therapy are to eliminate or
reduce periodontal pockets, decrease bleeding on probing and suppuration, and
maintain or gain clinical attachment.1,2 Because periodontal
diseases are opportunistic infections influenced by the host response, therapy
must be anti-infective. Adequate patient self-care and mechanical debridement
by dental hygienists are important to the success of nonsurgical periodontal therapy.
Other approaches, including antimicrobials and lasers, are considered adjuncts.3
They are intended to target microbial colonies and change the microflora in
areas less effectively reached by mechanical therapy.1 Lasers
produce light energy that penetrates tissues and produces thermal effects. This
modality is used in nonsurgical periodontal therapy for soft tissue debridement
(curettage), hemostasis, microbial inhibition or destruction, and biologic
responses to therapy.
Although lasers have been used in periodontal therapy for more than 25
years, this modality remains controversial. Numerous studies have supported, or
failed to support, efficacy beyond that provided by conventional treatment. It
is worthwhile to note the United States Food and Drug Administration (FDA) can
either clear a medical device based on safety data, or approve the device as
both safe and effective.4 The dental lasers discussed in this
article have received FDA clearance, a category that does not require
documentation of effectiveness.5
Dental hygienists are responsible for reviewing the evidence and making
decisions regarding use of devices—such as lasers—in patient care, while
considering their clinical experience and patient preference. Not all evidence
is equal: a hierarchy exists (Figure 1).6 When evaluating clinical
therapies or preventive strategies, the highest levels of evidence include
clinical practice guidelines, meta-analyses, and systematic reviews.
Clinical practice guidelines incorporate scientific evidence to systematically
develop recommendations about best practices for specific clinical situations.7
A systematic review is designed to answer a specific question by
comprehensively collecting and evaluating studies. All studies that meet
preestablished criteria for the highest level of evidence are systematically
identified, appraised, and summarized. Meta-analysis adds an additional step by
statistically combining results of some or all of the included studies. The
next highest level of evidence is a randomized controlled trial, in which
subjects are randomly assigned to the group(s) receiving a clinical protocol or
a control group receiving standard therapy, a placebo, or no treatment. The
design is intended to reduce bias when evaluating the effectiveness of an
intervention. This article will present the results of recent systematic
reviews and meta-analyses as they apply to the effectiveness of lasers as an
adjunct to scaling and root planing (SRP).
FIGURE 1. Hierarchies of research designs and levels of scientific evidence.
systematic reviews and meta-analyses of research in laser therapy have assessed
one type of laser used in nonsurgical periodontal therapy. In addition, because
SRP is the gold standard in nonsurgical therapy, most randomized controlled
trials have studied the effectiveness of the adjunctive use of a specific laser
technology to SRP alone. Lasers used in the treatment of periodontal and
peri-implant diseases include: diode lasers, which typically operate in the
810- to 980-nanometer (nm) wavelength;8 Nd:YAG lasers (800 nm to
1,100 nm); erbium lasers: Er:YAG and Er,Cr:YSGG (2940 nm and 2780 nm
respectively); and CO2 lasers (9,300 nm to 10,600 nm).9
In periodontal treatment, laser therapy—also known as phototherapy—is
used for sulcular debridement or soft tissue curettage, and for bactericidal
effects within periodontal pockets. While all of these laser technologies can
be used for soft tissue ablation, only Er:YAG and Er,Cr:YSGG lasers can be used
for calculus removal with minimal damage to the root surface.10
Unlike other therapeutic procedures, there is no standard, accepted protocol
for the use of lasers. As a rule, the performance of a given laser relates to
its absorption (or depth of penetration) into the tissues, and the absorption
depends on wavelength.11 Diode and Nd:YAG lasers penetrate deeply,
whereas Er:YAG, Er,Cr:YSGG and CO2 penetrate superficially.
Consequently, diode and Nd:YAG devices require cautious use when contacting
root surfaces. An exception is a low-power (660-nm to 810-nm) diode unit used
in combination with a photosensitizing agent for antimicrobial purposes in
photodynamic therapy. (This article does not discuss the laser-assisted new
attachment protocol using the Nd:YAG laser, as this is a trademarked surgical
procedure used by dentists and specialists.)11
Diode and Nd:YAG lasers: These lasers use deeply penetrating
wavelengths and target inflammatory tissue and pigmented pathogens for soft
tissue debridement, as well as hemostasis in acutely inflamed tissue. Both
types feature thin, flexible optic fibers that easily access periodontal
pockets. Care should be taken when using them near calculus and root surfaces,
however, as cementum damage is possible. Additionally, diode and Nd:YAG lasers
reportedly have a bactericidal effect in the periodontal pocket.12
Five recent systematic reviews or meta-analyses evaluated the effect of
diode (810 nm to 980 nm) and/or Nd:YAG lasers as an adjunct to SRP on clinical
signs of inflammation in patients with periodontitis or peri-implantitis.8,13–16
Most of the reviews indicated that diode and Nd:YAG lasers used as SRP adjuncts
could potentially provide additional short-term benefits. All authors concluded
that more long-term, well-designed randomized controlled trials are needed to
assess their effectiveness, as well as to establish appropriate
protocols—including the optimal optic fiber diameter, laser wavelength, power,
pulse repetition rate, and duration of laser exposure.
Based on the criteria set for quality and inclusion in a study by Slot et
al,13 only nine of 419 papers reviewed could be included in
the meta-analysis. This demonstrates that much of the literature regarding the
laser use and SRP for soft tissue curettage and antimicrobial effects is based
on lower quality evidence. The findings indicated that use of diode lasers and
SRP had no additional benefit in terms of pocket probing depth (PD), clinical
attachment loss (CAL), or plaque indices (PI) compared to SRP alone. Scores for
bleeding and gingival inflammation, however, showed a small, but statistically
significant advantage in favor of the adjunctive use of lasers.
Another systematic review indicated no significant difference in
nonsurgical periodontal therapy outcomes when comparing diode lasers and SRP
with SRP alone, but few studies qualified for inclusion.14
Subsequently, a systematic review included 10 studies comparing SRP to SRP with
the adjunctive use of diode lasers in treating chronic periodontitis.9
Five of the studies found that SRP and diode lasers were more effective than
SRP alone; two studies showed slight improvements in treatment outcomes with
the combined modalities, while three studies found no difference. Moderate
reductions in inflammation were noted in two studies when using the combined
modalities. The authors concluded that using SRP and lasers had some benefits
over SRP in improving clinical parameters of periodontitis and soft tissue
Compared to SRP alone, a meta-analysis examining Nd:YAG lasers identified
PD reductions with the use of SRP and Nd:YAG technology, but no differences
were observed in CAL gain or PI.15 An American Dental Association
(ADA) systematic review found small gains in CAL with the use of diode or
Nd:YAG lasers as adjuncts to SRP; however, the level of evidence supporting the
benefits of adjunctive laser use beyond that provided by conventional SRP was
In summary, using diode or ND:YAG lasers as adjuncts to SRP is safe, and,
compared to SRP alone, some evidence suggests this combined approach may
provide benefits in reducing inflammation and improving gains in CAL.
Nevertheless, additional evidence is needed to support the use of these types
of lasers in nonsurgical periodontal therapy.
Erbium lasers (Er:YAG and Er,Cr:YSGG): Erbium lasers have rigid quartz or
sapphire tips or metal cannulas. These types of superficially penetrating
lasers can be used on soft or hard tissues with low thermal effect. Therefore,
periodontal tissues, cementum, and titanium implant surfaces can be treated
with erbium lasers. Both types can also be used for calculus removal because
the deposits contain water, and the extreme evaporation of that moisture via
laser energy causes a microexplosion known as photomechanical ablation.10
When using these devices on the root surface, however, caution is needed to
avoid removing excessive cementum, which has hydration properties similar to
calculus.9 Although the evidence is mixed, it indicates potential
short-term benefits to the use of erbium lasers as a monotherapy17
or adjunct to SRP. Again, additional study is needed to strengthen existing
The ADA evidence-based review indicated slight gains in CAL with the use
of SRP and adjunctive erbium lasers, although the overall level of certainty
was rated as low.16 Zhao et al17 evaluated the Er:YAG
laser as a monotherapy in nonsurgical periodontal therapy, and also when used
in conjunction with SRP in patients with periodontitis. Although the study
found short-term benefits in ER:YAG monotherapy similar to SRP, they did not
extend long term. This laser's possible effectiveness as a monotherapy has led
to the suggestion it might be used for periodontal debridement in patients who
fear local anesthesia commonly used for SRP. Additional studies of this use are
needed to provide evidence showing clinical outcomes similar to traditional
therapy and gauge patient acceptance or preference.
A systematic review and meta-analysis of various laser wavelengths used
for treatment of peri-implantitis included a meta-analysis specific to the
Er:YAG laser.18 It showed a possible advantage in reducing
inflammation at 6 months, but no benefit in relation to PD or CAL compared to
traditional nonsurgical interventions that included debridement using plastic
or titanium curets, with, or without, chlorhexidine irrigation and air abrasives.
Another systematic review designed to assess nonsurgical and surgical
approaches to management of peri-implantitis included randomized controlled
trials evaluating the Er:YAG laser compared with an air abrasive device.19
The authors noted small improvements in clinical signs of peri-implantitis for
both approaches, and a short-term reduction in bacterial counts for the
Er:YAG-assisted nonsurgical periodontal therapy. While some advantages have
been noted for the use of erbium lasers in conjunction with SRP, more
long-term, controlled studies are needed to provide further evidence of their
Erbium lasers also have limitations. The rigid tips can be difficult to
adapt in all areas of the root surfaces. In addition, cementum can exhibit
micro-irregularities following laser instrumentation. Finally, hemostasis is
challenging because the superficially penetrating wavelength is not absorbed by
These systematic reviews collectively suggest that further study—with
standardized protocols—is needed before consensus can be reached regarding the
effectiveness of lasers in nonsurgical periodontal therapy. Although
preestablished settings on the devices can provide guidance for use, tissue
composition and the level of inflammation, infection, and keratinization varies
from patient to patient—and from site to site in the same patient.21
These variations preclude researchers from combining and synthesizing results
of individual studies, as well as the clinician's ability to assess each approach
using existing evidence.
Clinicians should consider the evidence, cost of these devices, as well
as their individual experience when making decisions regarding laser use in
nonsurgical periodontal therapy.
Carbon dioxide (CO2) lasers: This laser technology is not typically
used for root debridement. The delivery system is not appropriate for insertion
and adaptation in periodontal pockets. Thus, it is primarily recommended for
nonsurgical periodontal therapy sometimes fails to remove periodontal pathogens
and infection. In the presence of photosensitizing dyes, certain microbes—such
as Porphyromonas gingivalis, Treponema denticola, Tannerella
forsythia, and Aggregatibacter actinomycetemcomitans—are susceptible
to low-power diode lasers. Antimicrobial photodynamic therapy as an adjunct to
SRP has been suggested. With this treatment, microorganisms selectively
incorporate the photosensitizer and absorb the low-power laser to induce oxygen
and free radicals that prove toxic to bacteria.1,22 Although this
approach has been evaluated in randomized controlled trials that showed it to
be effective against periodontal pathogens, systematic reviews and
meta-analyses have reported controversial results regarding the benefits of
photodynamic therapy in nonsurgical periodontal therapy. More recent evidence
supports adjunctive use of photodynamic therapy, while stressing the need for
additional long-term studies.
Compared to conventional use of SRP, the ADA systematic review found
moderate evidence of improved gains in CAL when photodynamic therapy was used
as an adjunct to SRP,16 whereas the same review and others rated
evidence for alternative laser therapies as low.
A consensus paper of the International Academy of Periodontology reports
that photodynamic therapy as an adjunct to SRP provides short-term benefits in
PD reduction and gains in CAL, and suggests that long-term studies and
randomized controlled trials are needed. In addition, some promise was noted
for photodynamic therapy and SRP in periodontal maintenance therapy.2
When compared to SRP alone, a 2013 systematic review indicates that SRP
and photodynamic therapy provide superior reductions in PD and gains in CAL for
3 months after therapy. This benefit was not observed at 6 months, however.23
Council on Scientific Affairs cautions that practitioners need proper training
in the use of lasers, and should only use the devices within their licensed
scope of practice, training, and experience.5 The American Dental
Hygienists' Association identifies soft tissue curettage (not specifically
using lasers, however), as legal within the scope of dental hygiene practice in
23 states.24 Guidance for safe dental laser use is provided by
American National Standards Institute Standard Z136.1: Safe Use of Lasers, and
Z136.3: Safe Use of Lasers in Health Care.25
Although it is perplexing to find conflicting
reports about the effectiveness of lasers in nonsurgical periodontal therapy,
strong evidence is lacking to support lasers and photodynamic therapy as
adjuncts to SRP. Weak evidence does not mean, conversely, that these devices
have no benefit. It appears that inconsistent protocols and study designs, and
variations in the diameter of optic fibers, laser wavelengths, power, pulse
repetition, and duration of laser exposure affect researchers' ability to
combine results and make strong recommendations for or against their use.
Dental hygienists should continue to monitor the evidence and consider the cost
of these devices when making any decisions regarding patient care.
- Feres M, Faveri M, Figueiredo LC, et al. Group B. Initiator paper.
Non-surgical periodontal therapy: mechanical debridement, antimicrobial agents
and other modalities. J Int Acad Periodontol. 2015;17(Suppl 1):21–30.
- Lang NP, Feres M, Corbet E, et
al. Group B. Consensus paper. Non-surgical periodontal therapy: mechanical
debridement, antimicrobial agents and other modalities. J Int Acad
Periodontol. 2015;17(Suppl 1):34–36.
- Lang NP. Group B. Reactor
report. Non-Surgical Periodontal Therapy: Mechanical Debridement, Antimicrobial
Agents and Other Modalities. J Int Acad Periodontol. 2015;17(Suppl
- United States Food and Drug
Administration. Medical Devices: 510(K) clearances. Available at:
Accessed January 25, 2017.
- American Dental Association, ADA
Council on Scientific Affairs. Statement on Lasers in Dentistry. Available at:
Accessed January 25, 2017.
- Forrest JL, Miller SA. EBDM
in Action: Developing Competence in EB Practice. Colbert, Washington:
ebdLibrary LLC; 2016.
- Institute of Medicine: Shaping
the Future for Health. Crossing the Quality Chasm: A New Health System for the
21st Century. Available at: nationalacademies.org/hmd/~/media/Files/Report
Files/2001/Crossing-the-Quality-Chasm/Quality Chasm 2001 report brief.pdf. Accessed January 25, 2017.
- Qadri T, Javed F, Johannsen G,
Gustafsson A. Role of diode lasers (800–980 nm) as adjuncts to scaling and root planing in the treatment of chronic
periodontitis: a systematic review. Photomed Laser Surg.
- Mizutani K, Aoki A, Coluzzi D, et al. Lasers in minimally invasive
periodontal and peri-implant therapy. Periodontol 2000. 2016;71:185–212.
- Japanese Society for Laser Dentistry. Safety guidelines for the laser
removal of dental calculus. Laser Ther. 2012;21:137–145.
- Aoki A, Mizutani K, Schwarz F, et al. Periodontal and peri-implant
healing following laser therapy. Periodontol 2000. 2015;68:217–269.
- Romanos G. Current concepts in the use of lasers in periodontal and
implant dentistry. J Indian Soc Periodontol. 2015;19:490-494.
- Slot DE, Jorritsma KH, Cobb CM, Van der Weijden FA. The effect of the
thermal diode laser (wavelength 808–980nm) in non-surgical periodontal therapy:
a systematic review and meta-analysis. J Clin Periodontol.
- Sgolastra F, Sevverino M, Gatto R, Monaco A. Effectiveness of diode
laser as adjunctive therapy to scaling and root planing in the treatment of
chronic periodontitis: a meta-analysis. Lasers Med Sci.
- Sgolastra F, Severino M, Petrucci A, Gatto R, Monaco A. Nd:YAG laser
as an adjunctive treatment to nonsurgical periodontal therapy: A meta-analysis.
Lasers Med Sci. 2014;29:887–895.
- Smiley CJ, Tracy, SL, Abt E, et al. Systematic review and
meta-analysis on the nonsurgical treatment of chronic periodontitis by means of
scaling and root planing with or without adjuncts. J Am Dent Assoc.
- Zhao Y, Yin Y, Tao L, Nie P, Tang Y, Zhu M. Er:YAG laser versus
scaling and root planing as alternative or adjuvant for chronic periodontitis
treatment: a systematic review. J Clin Periodotol. 2014;41:1069–1079.
- Kotsakis GA, Konstantinidis I, Karoussis IK, Ma X, Chu H. Systematic
review and meta-analysis of the effect of various laser wavelengths in the
treatment of peri-implantitis. J Periodontol. 2014;85:1203–1213.
- Mahato N, Xiaohong W, Wang L. Management of peri-implantitis: a
systematic review, 2010–2015. Springerplus. 2016;5:105.
- Colluzi DJ. Lasers for Phase One Periodontal Therapy. Available at:
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- LeBeau J. Laser Technology: Its role in treating periodontitis. Compend
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- Kikuchi T, Mogi M, Okabe I, et al. Adjunctive application of
antimicrobial photodynamic therapy in nonsurgical periodontal treatment: A
review of literature. Int J Mol Sci. 2015;16:24111–24126.
- Sgolastra F, Petrucci A, Severino M, Graziani F, Gatto R, Monaco A.
Adjunctive photodynamic therapy to non-surgical treatment of chronic
periodontitis: a systematic review and meta-analysis. J Clin Periodontol.
- American Dental Hygienists' Association. Dental hygiene practice acts
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From Dimensions of Dental Hygiene. February 2017;15(2):54-57.