SLPRCTCoDAS2024

Immediate effects of photobiomodulation on saliva production.

Amanda Rentero Gimenez do Amaral Silva, Lucas de Oliveira Cunha, Déborah Carollina Costa Silva and 3 others

PMID 38808859

WHAT IT FOUND

Photobiomodulation did not differ from placebo for self-perception or measured saliva in healthy adults.

Measured saliva increased at 9 J and decreased at 18 J and 24 J in both groups, so the laser alone cannot explain the changes.

Key findings

01Compared with placebo, photobiomodulation did not significantly change self-perception or measured saliva production.

02Measured saliva increased after 9 J and decreased after 18 J and 24 J in both groups, so the changes cannot be separated from the placebo procedure.

03Self-perception correlated only weakly with measured saliva at 18 J (rhô=0.282) and 24 J (rhô=0.450).

STILL TO COME

How it was doneWhat they foundWhat it means for SLPs

Read the rest of this summary

You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.

Already have one?

What it does not show

The study used healthy university adults, not patients with swallowing disorders or sialorrhea, so it does not show what would happen in the patients SLPs usually treat. It tested only immediate effects in one session, not effects after repeated treatment. The placebo group had significant changes in measured saliva as well, and the laser and placebo groups did not differ, so the laser alone cannot be identified as the cause. The placebo device still emitted a red guide light under 20 mW, and participants had to keep their mouths open for a long time, which may have influenced saliva. Self-perception was only weakly correlated with measured saliva at 18 J and 24 J, so patient-reported saliva may not reflect actual flow. The sample was mostly young and active, so it may not represent older patients with swallowing disorders.

Declared interests

The authors reported no financial support. The placebo equipment was lent by the manufacturer.

The easy way to misread this

Do not conclude that photobiomodulation reduces saliva. Measured saliva also changed significantly in the placebo group, and there was no statistically significant difference between the experimental and placebo groups.

Read it on PubMed →