The Effect of Diode Laser on Viability and Antibiotic Sensitivity of Streptococcus mutans Isolated From Dental Caries

Abstract

Streptococcus mutans is one of the major cariogenic microbial flora. In an attempt to determine the mutagenic effect of diode laser on the viability and antibiotic sensitivity of this bacteria; A total of 30 samples were collected from dental caries. The isolates were identified using by conventional identification methods and confirmed using VITEK2 system. Twenty-one isolates were recorded as Streptococcus spp and ten of them were identified as Streptococcus mutans. Antibiotic susceptibility profile for Streptococcus mutans isolates against ten antibiotics was tested. The results revealed that all the isolates were resistant to cefixime and cephalothin, nine of them were resistant to erythromycin, ampicillin, and nalidixic acid, seven isolates were resistant to tetracycline and bacitracin, whereas all isolates were sensitive to chloramphenicol, ciprofloxacin and gentamycin. The effect of the diode laser on the isolates (S5 and S10) was tested at different time intervals (1, 2, 5, and 10) min. The viability of Streptococcus mutans isolates was affected by the obvious change in the behaviour of the bacteria from resistance to sensitivity after Laser exposure

A Comparative study of the laser beam effect on some virulence factors of Staphylococcus aureus isolated from different sites of the human body

“…The result of the researcher resembles increased susceptibility of S. aureus isolates to Ciprofloxacin and Nitrofuranon after one minute of laser exposure, while the same isolates exhibit increased susceptibility to Gentamicin and Chloramphenicol after three to five minutes of laser exposure (antibiotic sensitivity is negligible) [25]. These results were in agreement with those of [28,29], who discovered that diode laser irradiation increases bacteria's susceptibility to antibiotics over time and at increasing doses.…”

“…There is no effect of irradiation on the synthesis of the enzymes (Catalase and Coagulase) or the fermentation of mannitol in just 15 isolates of S.aureus that are treated with a diode laser (2w) at various exposure durations. When S. aureus isolates were exposed to a photosensitizer under the same conditions, beta hemolysis activity decreased, but alpha-hemolysin production showed a 40% reduction (in toxin production) after 5 minutes of exposure (the results show a significant decrease in hemolysin production compared to control) [25].…”

“…following several (1,3,5) min exposures to a diode laser as seen in Figure (1,2,3,4). Results indicate that the majority of isolates become more or less susceptible to antibiotics at various times after 1,2,3,4 min exposure [25].…”

Isolation and diagnosis of Streptococcus mutans and Streptococcus sorbinus from patients with tooth decay and gingivitis

“…The results of the current study are consistent with previous studies, including the local results reached by Saleh with other researchers in 2023, where they showed isolates of S. mutans isolated from Baghdad patients were sensitive to Ciprofloxacin 100%). It was resistant to the anti-Cefixime by (100%) [33] and these results were identical to the results of the current study, and the results reached by the researchers Saleh and Abdel-Rahman in 2017 were consistent with the current study, where it appeared that the isolated S. mutans isolates from patients in Thi Qar Governorate were sensitive to anti-Imipenem by (78.3%) and Ciprofloxacin by (60.9%) and the study did not agree with the Ceftriaxone because its results were sensitive to bacteria (60.9%) While it was resistant by (100%) in the current study, the reason may be due to the size of the sample and the number of positive samples, as well as for the antibody Amikacin, which showed resistance, while in the current study, the bacteria were sensitive to it by (100%), the reason may be due to the indiscriminate use of antibiotics [34] The current study agreed with the results of a study in Argentina carried out in 2021 by researcher Bachmeier et al, that the bacterial isolates of S. mutans were sensitive to Amikacin (83.30%) and Ciprofloxacin (77.75%) [35] . As for S. sobrinus, the results showed that that isolation, which was only one isolation that was isolated during the study, had resistance to the antibodies Ceftazidime, Cephalexin, Cefixime and Ceftriaxone, while Amikacin, Tobramycin, Azithromycin and Levofloxacin were sensitive and were moderately sensitive to Imipenem, and because of the rarity of their isolation, they are present in small proportions in patients with caries and tooth decay, so studies on them are rather few, and the researcher Salman pointed out in 2015 in a study conducted on the sensitivity of S. sobrinus as being sensitive to ampicillin and Penicillin antagonists and less sensitive to chloramphenicol and Cefazolin [36] One of the main reasons for bacterial resistance to antibiotics is the horizontal transfer of genes, as it is the reason for the development of the ability of bacteria to resist pesticides and antibiotics through the mechanism of gene transfer from bacteria to other bacteria through plasmids or through viruses known as phages or through sexual filaments [37] .…”

Antibacterial Efficacy of 940 nm Diode Laser against Cariogenic Bacteria (Tooth Decay-causing Bacteria)

“…As a result, various antibacterial methods have a good bactericidal effect and do not have any negative side effects are required such as lasers. Rapid advancements in laser technology (including wavelengths, methods, and delivery systems) have allowed for its usage in a wide range of fields, including medicine, physics, biology, biotechnology, biochemistry, and dentistry 13 . It has been demonstrated that a variety of lasers, including diode lasers, Er-YAG, and Nd-YAG, exhibit bactericidal properties 14 .…”