AAP best evidence consensus on lasers (2018): three systematic reviews, every pooled gain under a millimeter

What it says#

In 2016 the American Academy of Periodontology started a format it calls the best evidence consensus, or BEC: a panel of experts, a set of focused clinical questions, systematic reviews commissioned in advance, and consensus statements built on both the published data and the panel's experience. The AAP describes the model as one that uses current, high-quality published literature and the expert opinion of periodontal thought leaders to provide guidance on innovative topics for which there is insufficient evidence to arrive at definitive conclusions. Lasers were the second topic. Ten panelists met in Chicago in February 2017, and the proceedings, a consensus statement by Mills and colleagues, a commentary by Noraian and Cobb, and three systematic reviews, ran together in the July 2018 Journal of Periodontology.

The first review, by Chambrone, Ramos and Reynolds, asked what infrared lasers do in moderate to severe periodontitis, alone or added to nonsurgical or surgical therapy. It searched MEDLINE, EMBASE and CENTRAL through March 2016 for randomized trials with at least 3 months of follow-up in adults, screened 475 articles and included 28. Its conclusion: nonsurgical treatment with scaling and root planing plus an infrared diode laser, and surgical treatment of chronic periodontitis with Er:YAG laser therapy alone, may promote statistically significant improvements in probing depth and clinical attachment level. Then the qualifier that matters: these gains are relatively small, under 1 mm, and provide modest clinical relevance compared with SRP alone. The level of certainty was low to moderate, and most of the strengths of clinical recommendation were weak or based on expert opinion.

The second review, by Chambrone, Wang and Romanos, covered antimicrobial photodynamic therapy, the technique that pairs a photosensitizer with a low-power diode laser, as an adjunct to debridement in periodontitis or peri-implantitis. It searched through March 2017, screened 729 articles and included 28 papers reporting 26 studies. Four sets of meta-analysis showed a potential statistically significant benefit of aPDT for attachment level in the nonsurgical treatment of aggressive periodontitis and for probing depth in nonsurgical treatment of both aggressive and chronic periodontitis. Again the differences were under 1 mm, the certainty low to moderate, and the strengths of recommendation mostly expert opinion. The authors' conclusion is a tie rather than a win: aPDT may provide similar clinical improvements in probing depth and attachment level compared with conventional periodontal therapy.

The third review, by Lin, Suárez López Del Amo and Wang, covered lasers in peri-implant mucositis and peri-implantitis. It searched from January 1980 to June 2016, required at least 10 patients and 6 months of follow-up, selected 22 articles and meta-analyzed 11. The first finding is an absence: the outcomes of using lasers as a monotherapy could not be evaluated, because no controlled studies existed, so everything reported is a laser added to surgical or nonsurgical treatment. For the nonsurgical approach the weighted mean differences were 0.15 mm for probing depth (P = 0.50), -0.10 mm for attachment level (P = 0.32), 21.08% for bleeding on probing (P = 0.02), -0.07 for plaque index (P = 0.002), -0.22 mm for marginal bone level (P = 0.04) and -0.11 mm for recession (P = 0.34). For the surgical approach with long-term follow-up: probing depth 0.45 mm (P = 0.11), attachment level 0.22 mm (P = 0.56), bleeding on probing 7.26% (P = 0.76) and plaque index -0.09 (P = 0.84). The authors call the benefit minimal, with more bleeding reduction in the short term after nonsurgical therapy the one signal, and note that the evidence allowed analysis of Er:YAG, CO2 and diode lasers only.

The AAP's own summary of the meeting, issued on September 11, 2018, says the group found that when laser treatment is used in addition to mechanical treatment, similar or slightly better clinical outcomes are observed when compared with laser usage alone, and that current evidence suggests there is no additional benefit to lasers beyond what is seen with traditional periodontal surgery. The AAP was careful about what that does and does not mean. Its president at the time, Steven R. Daniel, said the findings are not meant to insinuate that laser usage is more or less beneficial over traditional periodontal therapy or to imply an Academy position on its use in patient care, and that in the absence of a critical mass of evidence, practitioners must rely on their judgment and training.

Who it applies to#

Any practice that treats periodontitis or peri-implant disease and is deciding whether a laser belongs in that treatment. The periodontitis reviews enrolled adults with moderate to severe disease, chronic or aggressive under the vocabulary in use before the 2017 World Workshop; the peri-implant review covered mucositis and peri-implantitis around implants in function.

It does not settle laser use for anything the reviews did not test. Laser monotherapy around implants has no controlled evidence at all. Wavelengths and devices without qualifying trials were not analyzed, which is not the same as being ruled out. And the consensus is not a guideline: the AAP's format is explicitly for topics where the evidence is too thin for definitive conclusions, so a practitioner who reaches a different judgment for an individual patient is not violating an Academy rule.

What changed#

This was the AAP's first formal look at lasers under the BEC model, following cone beam computed tomography in 2017; periodontal and peri-implant phenotype modification followed in 2020 and biologics in 2022. What the proceedings changed is the burden of proof in the operatory. Before 2018 a practice could point to individual trials showing statistically significant laser gains. After 2018 the specialty's own reviews put those gains in context: statistically significant in places, under a millimeter everywhere, low to moderate certainty, and mostly carried by expert opinion rather than by strong data.

Where the source is#

The document under the title is Mills and colleagues, American Academy of Periodontology best evidence consensus statement on the efficacy of laser therapy used alone or as an adjunct to non-surgical and surgical treatment of periodontitis and peri-implant diseases, Journal of Periodontology 2018, volume 89, issue 7, pages 737 to 742; the link resolves through the DOI to the Wiley page. When this entry was written the publisher's site refused every automated request, and the PubMed record for the consensus statement carries no abstract, so nothing in this entry is quoted from the consensus statement itself. What is reported here comes from three sources that were read in full: the AAP's own announcement of the proceedings on perio.org, and the PubMed abstracts of the three best evidence reviews published alongside the statement (PMIDs 29682757, 30133749 and 30133748). The commentary by Noraian and Cobb, at pages 804 to 806, also has no abstract on PubMed and is not quoted here. Readers with institutional access should read the consensus statement itself; the figures and conclusions above are the reviews' own.