Open Access Research Article

Phototoxic Effect of Visible Blue Light on Porphyromonas Gingivalis and Aggregatibacter Actinomycetemcomitans

Mohsen Ali Al Hamzi1, Ayman Ahmed Ahmed Al jorany2, Hassan A Al-Shamahy2* and Amani Abdulhakeem Al Sharani3

1Department of Conservative Dentistry and Oral Health, Sana’a University, Republic of Yemen

1Medical Microbiology and Clinical Immunology, Sana’a University, Republic of Yemen

1Oral Medicine and Periodontology Department, University of Sciences and Technology, Yemen

Corresponding Author

Received Date: October 17, 2019;  Published Date: November 18, 2019


Background: Chronic gingivitis is a common disease, especially among adult patients who often develop periodontal pocket and the occurrence gradual loss of the periodontal attachment. A wide range of microorganisms is known to be associated with periodontal disease, including Porphyromonas gingivalis (Pg) and Aggregatibacter actinomycetemcomitans (Aa).

Objectives: Therefore, a study was conducted to determine the effect of phototoxicity of visible blue light (vBL) on Aa and Pg Clinical isolates from chronic periodentitis patients, and to study their antibiotic sensitivity against selected antibiotics. Methods: The test was carried out on 15 strains of Aa and 15 strains of Pg isolated from pockets of chronic periodentitis patients aged between 30-50 years old with pocket depths of 5-6mm. Bacteria cultured, isolated, identified by standard bacteriological methods, and then exposed to visible blue light for different periods of time. After bacterial cultures were exposed to light, bacterial killing rates were calculated from a colony forming unit (CFU) after 48 hours of anaerobic incubation.

Results: There was a decrease in CFU for both microorganisms and the result is increased with the increase of exposure to vBL, from zero, 20, 40 and 60 secs.

Conclusion: There was a phototoxic effect of visible blue light emitted by a light therapy device against anaerobic gingival pathogens and exposure to blue light is effective in reducing gum pathogens. It is recommended to use an adjuvant external optical enhancer and to expose pathogens to visible light for clinical antimicrobial treatment.


Blue light; CFU; Anaerobic periodontal pathogen
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