Maria Olivia Marcondes Pinto, Victor E Arana-Chavez, Livia Tosi Trevelin, Patricia Moreira Freitas, Sérgio Luiz Pinheiro
{"title":"Use of Er:YAG Laser for Disinfection of Infected Carious Dentin: Microbiological Evaluation and Scanning Electron Microscopy Analysis.","authors":"Maria Olivia Marcondes Pinto, Victor E Arana-Chavez, Livia Tosi Trevelin, Patricia Moreira Freitas, Sérgio Luiz Pinheiro","doi":"10.1177/25785478261444876","DOIUrl":null,"url":null,"abstract":"<p><strong>Objective: </strong>To evaluate the antimicrobial efficacy of Er:YAG laser for disinfection of softened carious dentin using subablative parameters.</p><p><strong>Background: </strong>Current literature lacks robust scientific evidence supporting the use of Er:YAG laser for disinfection of the entire carious dentin without mechanical removal.</p><p><strong>Methods: </strong>Ninety permanent third molars were used; 75 were allocated to microbiological evaluation and 15 to scanning electron microscopy. Artificial dentin carious lesions were produced using a microcosm biofilm model, and specimens were randomly assigned to five groups according to the cavity disinfection protocol (<i>n</i> = 15): Group C (positive control)-carious lesions with no disinfection procedure; Group antimicrobial photodynamic therapy (aPDT, negative control)-application of 0.005% methylene blue followed by low-level laser irradiation delivering 9 J of energy; Group Er:YAG, parameter A-irradiation with Er:YAG laser at 50 mJ of energy; Group Er:YAG, parameter B-irradiation at 40 mJ; and Group Er:YAG, parameter C-irradiation at 20 mJ. A repetition rate of 15 Hz was used for all Er:YAG-irradiated groups. Microbiological outcomes (CFU/mL) were analyzed using the nonparametric Kruskal-Wallis test followed by Dunn's post hoc test, with a significance level set at 5%.</p><p><strong>Results: </strong>A significant microbial reduction in dentin carious lesions was observed after irradiation with Er:YAG laser at 50 mJ (parameter A) and aPDT (<i>p</i> < 0.0001). In contrast, irradiation at 40 mJ (parameter B) and 20 mJ (parameter C) did not result in a significant reduction of the cariogenic microbiota (<i>p ></i> 0.05). No significant difference was detected between the microbial reduction achieved with Er:YAG laser at 50 mJ (parameter A) and aPDT (<i>p ></i> 0.05).</p><p><strong>Conclusions: </strong>Er:YAG laser irradiation at 50 mJ demonstrated antimicrobial efficacy comparable with aPDT for disinfection of softened carious dentin, with a shorter operative time, supporting its potential use as an alternative treatment in minimally invasive dentistry.</p>","PeriodicalId":94169,"journal":{"name":"Photobiomodulation, photomedicine, and laser surgery","volume":" ","pages":"387-393"},"PeriodicalIF":1.8000,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Photobiomodulation, photomedicine, and laser surgery","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1177/25785478261444876","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2026/4/15 0:00:00","PubModel":"Epub","JCR":"Q2","JCRName":"SURGERY","Score":null,"Total":0}
引用次数: 0
Abstract
Objective: To evaluate the antimicrobial efficacy of Er:YAG laser for disinfection of softened carious dentin using subablative parameters.
Background: Current literature lacks robust scientific evidence supporting the use of Er:YAG laser for disinfection of the entire carious dentin without mechanical removal.
Methods: Ninety permanent third molars were used; 75 were allocated to microbiological evaluation and 15 to scanning electron microscopy. Artificial dentin carious lesions were produced using a microcosm biofilm model, and specimens were randomly assigned to five groups according to the cavity disinfection protocol (n = 15): Group C (positive control)-carious lesions with no disinfection procedure; Group antimicrobial photodynamic therapy (aPDT, negative control)-application of 0.005% methylene blue followed by low-level laser irradiation delivering 9 J of energy; Group Er:YAG, parameter A-irradiation with Er:YAG laser at 50 mJ of energy; Group Er:YAG, parameter B-irradiation at 40 mJ; and Group Er:YAG, parameter C-irradiation at 20 mJ. A repetition rate of 15 Hz was used for all Er:YAG-irradiated groups. Microbiological outcomes (CFU/mL) were analyzed using the nonparametric Kruskal-Wallis test followed by Dunn's post hoc test, with a significance level set at 5%.
Results: A significant microbial reduction in dentin carious lesions was observed after irradiation with Er:YAG laser at 50 mJ (parameter A) and aPDT (p < 0.0001). In contrast, irradiation at 40 mJ (parameter B) and 20 mJ (parameter C) did not result in a significant reduction of the cariogenic microbiota (p > 0.05). No significant difference was detected between the microbial reduction achieved with Er:YAG laser at 50 mJ (parameter A) and aPDT (p > 0.05).
Conclusions: Er:YAG laser irradiation at 50 mJ demonstrated antimicrobial efficacy comparable with aPDT for disinfection of softened carious dentin, with a shorter operative time, supporting its potential use as an alternative treatment in minimally invasive dentistry.