Antimicrobial effect of ozonated water on bacteria invading dentinal tubules

Effects of systemic ozone administration on the fresh extraction sockets healing: a histomorphometric and immunohistochemical study in rats

OBJECTIVE

Studies have highlighted numerous benefits of ozone therapy in the field of medicine and dentistry, including its antimicrobial efficacy against various pathogenic microorganisms, its ability to modulate the immune system effectively, reduce inflammation, prevent hypoxia, and support tissue regeneration. However, its effects on dental extraction healing remain to be elucidated. .Therefore, this study aimed to evaluate the effects of systemically administered ozone (O3) at different doses in the healing of dental extraction sockets in rats.

METHODOLOGY

To this end, 72 Wistar rats were randomly divided into four groups after extraction of the right upper central incisor: Group C - control, no systemic treatment; Group OZ0.3 - animals received a single dose of 0.3 mg/kg O3; Group OZ0.7 - a single dose of 0.7 mg/kg O3; and Group OZ1.0 - a single dose of 1.0 mg/kg O3, intraperitoneally. In total, six animals from each group were euthanized at 7, 14, and 21 days after the commencement of treatment. Bone samples were harvested and further analyzed by descriptive histology, histomorphometry, and immunohistochemistry for osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP) protein expression.

RESULTS

All applied doses of O3 were shown to increase the percentage of bone tissue (PBT) after 21 days compared to group C. After 14 days, the OZ0.7 and OZ1.0 groups showed significantly higher PBT when compared to group C. The OZ1.0 group presented the most beneficial results regarding PBT among groups, which denotes a dose-dependent response. OCN immunostaining was higher in all groups at 21 days. However, after seven and 14 days, the OZ1.0 group showed a significant increase in OCN immunostaining compared to C group. No differences in TRAP+ osteoclasts were found between groups and time points.

CONCLUSION

Therefore, O3 therapy at higher doses might be beneficial for bone repair of the alveolar socket following tooth extraction.

Effect of Different Electroconductive Root Canal Irrigations on the Accuracy of Different Apex Locators: An In Vitro Comparative Study

Aim

An accurate working length (WL) estimation is fundamental to a successful endodontic therapy. The objective of this comparative in vitro research was to investigate the performance of iPex II and the Root ZX Mini electronic apex locators (EALs) in measuring root canal WL with different irrigant solutions and their relation to the electrical conductivity of irrigation solutions.

Materials and Methods

Seventy sound permanent lower premolar teeth, each with a single root and developed apices, were used. Under an X15 stereomicroscope, the real working length was determined with the aid of a #10 file. After that, teeth were placed into an alginate model, and the iPex II and Root ZX Mini were used for the detection of electronic working length with various irrigants. Seventy teeth were randomly distributed into seven groups, 10 per each group (group I: dry canal; group II: distilled water; group III: ozonated water; group IV: 5% sodium hypochlorite (NaOCl); group V: 2% chlorhexidine, group VI: 17% ethylenediaminetetraacetic acid (EDTA) solution, and group VII: 17% EDTA gel). The difference in WL was calculated by deducting real working length from its electronic working length. The study also evaluates the electrical conductivity of the seven endodontic irrigant solutions. The two-way analysis of variance (ANOVA) test was used for statistical analysis.

Results

Statistically, neither both types of EALs (P = 0.088) nor various irrigating solutions with varying electrical conductivities (P = 0.099) significantly affect the accuracy of EL estimation.

Conclusions

There were no significant differences between the accuracy of the Root ZX Mini and the iPex II. The accuracy of both apex locators is unaffected in the presence of various irrigation solutions with varying electrical conductivities in this research.

Comparative Evaluation of Antifungal Efficacy of 3% Sodium Hypochlorite, 2% Chlorhexidine Gluconate, Ozonated Water, Alum Water, and Normal Saline Solutions against Endodontopathogenic Microorganism, Candida Albicans: A Microbiological In Vitro Study

Aims and objective

To compare and evaluate the antifungal efficacy of 3% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX) gluconate, 4 mg/mL ozonated water, and 2M alum water against Candida albicans (C. albicans).

Materials and methods

A total of 35 patients were selected from those attending the outpatient department of Pedodontics and Preventive Dentistry at Santosh Dental College and Hospitals, Ghaziabad. Their salivary samples were taken and cultured on a Sabouraud's dextrose agar (SDA) plate. The antifungal efficacy of 3% NaOCl, 2% CHX gluconate, 4 mg/mL concentration of ozonated water, and 2M alum water was assessed against clinical strains of C. albicans with the help of agar well diffusion method. The microbial isolates were inoculated into 10 mL of sterile peptone water and incubated at 37°C for 8 hours. The cultures were swabbed on the surface of sterile Mueller-Hinton agar plates using a sterile cotton swab. Five wells of 6 mm diameter were punched in each Petri dish. Around 100 µL of each test solution was poured into the designated wells. Further, the plates were incubated in an upright position at 37°C for 24 hours. The antifungal activity of the test solutions was determined by measuring the diameter of the inhibition zone in mm produced against the Candida isolates, and means were calculated.

Results

It was observed that all test solutions used in this study were inhibitory against C. albicans but with a variation in the size of inhibitory zones. According to the means of the diameter of inhibitory zones for all test solutions, the 3% NaOCl represented the statistically significant largest average zones of inhibition against C. albicans, followed by 2% CHX when compared with the other two test solutions alum water and ozonated water. Ozonated water produced the smallest mean inhibitory zone.

How to cite this article

Sharma A, Naorem N, Srivastava B, et al. Comparative Evaluation of Antifungal Efficacy of 3% Sodium Hypochlorite, 2% Chlorhexidine Gluconate, Ozonated Water, Alum Water, and Normal Saline Solutions against Endodontopathogenic Microorganism, Candida Albicans: A Microbiological In Vitro Study. Int J Clin Pediatr Dent 2024;17(S-1):S17-S24.

Ozone: An Adjunct in Dental Treatment

Ozone is utilized in dentistry as ozonated oils, ozonated water, and gaseous ozone. The application of ozone in all specialties of dentistry has been demonstrated to be biocompatible. It has been demonstrated to encourage the remineralization of recently carious teeth, and it is utilized in dental caries and intracanal irrigants in endodontic treatment. Herpes virus infection, avascular osteonecrosis of the jaw, and alveolitis have all been treated with it. It can be applied as a supplement in the surgical and ongoing stages of periodontal disease and also hinders plaque formation. The purpose of the present review article is to discuss the numerous application of ozone in dentistry.

Research methods assessing sodium hypochlorite cytotoxicity: A scoping review

Sodium hypochlorite (NaOCl) cytotoxicity has been assessed using different methodologies, which has led to arbitrary interpretations. This scoping review aimed to discuss the different methodological protocols for assessing NaOCl cytotoxicity. A literature review performed in the PubMed and Embase databases up to July 2023 identified manuscripts reporting NaOCl cytotoxicity. The dataset identified 546 publications, further screened by 2 reviewers. Ninety studies were identified and mined methodologically to collect information on cell type, cytotoxicity assay, NaOCl dilution solutions, presence of fetal bovine serum (FBS), and NaOCl exposure time. The culture medium used in cytotoxicity assays contains buffering substances that neutralize the pH of NaOCl, thus reducing its cytotoxicity, an approach that may lead to bias when solutions with different pH are compared. For short exposure periods, as in simulations to evaluate the contact between irrigant and periapical tissue cells during chemo-mechanical preparation, NaOCl dilution should be performed with saline, which does not buffer the irrigant. For long exposure periods, as in simulations of irrigant extrusions, NaOCl should be diluted in the culture medium, to reproduce the expected buffering effect occurring in extrusions. The presence of FBS in culture medium can decrease NaOCl toxicity. There is no standardization of NaOCl cytotoxicity methodologies. This poses the risk of arriving at incorrect results and, therefore, pertinent tests must be refined.

CLSM-Guided Imaging for Quantifying Endodontic Disinfection

Elimination of microbes in the root canal system is crucial for achieving long-term success in endodontic treatment. Further efforts in study design and standardization are needed in order to improve the validity and comparability of in vitro results on endodontic disinfection procedures, in turn improving clinical outcomes. This study optimizes two models at all steps: tooth selection, pretreatment, inoculation method (by growth or centrifugation), and confocal laser scanning microscopy (CLSM)-guided imaging of LIVE/DEAD-stained specimens. Individual anatomical conditions lead to substantial differences in penetration depth. Sclerosis grading (SCG), a classification system introduced in this study, provides information about the sclerosis status of the dentine and is helpful for careful, specific, and comparable tooth selection in in vitro studies. Sonically activated EDTA for the pretreatment of roots, inoculation of Enterococcus faecalis in an overflow model, 3-4 weeks of incubation, as well as polishing of dentine slices before staining, led to advances in the visualization of bacterial penetration and irrigation depths. In contrast, NaOCl pretreatment negatively affected performance reproducibility and should be avoided in any pretreatment. Nonsclerotized teeth (SCG0) can be used for microbial semilunar-shaped inoculation by centrifugation as a "quick-and-dirty" model for initial orientation. In conclusion, CLSM-guided imaging for quantifying endodontic infection/disinfection is a very powerful method after the fine-tuning of materials and methods.

Apoptosis Regulation in Dental Pulp Cells and PD-1/PD-L1 Expression Dynamics Under Ozone Exposure - A Pilot Approach

This study aimed to determine the effect of ozone on the expression of Bax and Bcl-2 genes in dental pulp cells. Additionally, the programmed cell death protein 1, programmed death-ligand 1, and CD200 antigens were determined in lymphocytes to assess their surface expression. Dental pulp cells were cultured from extracted healthy third molars and characterized as dental pulp stromal cells. Gene expression of Bcl-2 and Bax was analyzed at 0 s, 6 s, and 12 s of ozone exposure using real-time PCR. Lymphocytes from dental pulp were subjected to ozone exposure for 12 s and PD-1, PD-L1, and CD200/CD200R expression was analyzed by flow cytometry. Upon exposure to ozone for 6 s, the Bcl-2 expression decreased significantly to -0.09, and at 12 s, it increased significantly to 0.3. Bax gene expression level increased significantly to 0.188 after 6 s exposure, and at 12 s, to 0.16. Lymphocytes exposed to ozone for 12 s showed minimal changes in PD-1, PD-L1, and CD200/CD200R expression levels, indicating that oxidative stress does not impact the signaling pathways regulating these molecules. The significant upregulation of Bcl-2 at 12 s highlights the cells' effort to protect themselves from prolonged oxidative stress, possibly tipping the balance toward cell survival and tissue repair. However, the absence of changes in PD-1 and PD-L1 expression on lymphocytes under oxidative stress suggests that these molecules are not sensitive to oxidative stress in this context.

Ozone Therapy as an Adjuvant in the Treatment of Periodontitis

The current study aimed to assess the efficacy of ozone therapy in the treatment of stage II and stage III periodontitis. This prospective split-mouth study selected patients who were diagnosed with either stage II or stage III periodontitis. All patients were treated with scaling and root-planing (SRP) on the control side and SRP with ozone therapy on the test side. Probing depth (PD), clinical attachment loss (CAL), O'Leary plaque index (PI), and bleeding on probing (BOP) scores were recorded at baseline and six weeks after the SRP treatment. A total of 46 patients were selected for this study, including 31 males and 15 females. All periodontal variables (PD, CAL, PI, and BOP) showed significant changes (p < 0.0001) from baseline to six weeks. Moreover, significant changes (PD = 0.0001, CAL = 0.0001, PI = 0.042 and BOP = 0.0001) were also observed between the control and test sides. Gender showed no significance on periodontal variables (p > 0.05) except PD on the test side (p = 0.030). In addition, periodontal stages and grades showed no significant changes (p > 0.05) in any periodontal variables on both sides. Ozone therapy significantly improves the periodontal condition compared to SRP treatment alone. However, the stages and grades of periodontitis do not influence the outcome of ozone therapy.

Comparison of ıntracanal ozone and low-level laser therapy on postoperative pain in vital teeth with symptomatic apical periodontitis:placebo-controlled randomize trial

The aim of this study was to compare the effect of ozone and low-level-laser therapy (LLLT) on postoperative pain after root canal treatment in symptomatic apical periodontitis on vital teeth. Eighty patients were divided into four groups using a web program as follows: LLLT placebo (mock laser therapy), LLLT, Ozone placebo (mock ozonated water irrigation), and Ozone. Postoperative pain levels for 7 days after treatment and percussion pain levels at the 7th day were recorded on the visual analog scale. A regression analysis, Cochran's Q test, Chi-square test, Kruskal-Wallis tests were performed to analyze the data (P=.05). A regression analysis demonstrated that the most effective variables are "group" and "jaw" (P=0.01). Pain in the lower jaw is higher than the upper jaw. There was difference between the groups on postoperative pain at the days 1, 2, and 3; however, there was no significant difference on other days. LLLT and ozone groups had less postoperative pain and pain on percussion. Low-level laser and ozone therapy are useful methods on postoperative-pain in vital symptomatic teeth ,but they don't have superiority to each other.

In vitro comparative evaluation of physical and chemical properties of surface enamel after using APF and SDF with or without laser activation

PURPOSE

To evaluate and compare the changes in physical and chemical properties of the enamel surface after application of Silver Diamine Fluoride (SDF), Acidulated Phosphate Fluoride (APF), LASER activated SDF and LASER activated APF.

METHODS

Sample consisted of 72 freshly extracted healthy human premolar teeth, extracted for orthodontic purpose, free from caries, fracture or any anomalies. The selected samples were randomly divided into four groups (n = 18): Group 1 (SDF); Group 2 (APF); Group 3 (LASER activated SDF) and Group 4 (LASER activated APF). All samples were evaluated for values of DIAGNOdent at baseline, after demineralisation and after remineralisation. They were further divided and assessed for colour changes, surface alterations and fluoride content of surface enamel using Spectrophotometer, Scanning Electron Microscopy and Energy Dispersive X-ray Spectrometry respectively. The statistical analysis was done using One-Way ANOVA, Tukey's HSD test, Mann-Whitney U test and Kruskal-Wallis Test.

RESULTS

Highest remineralising potential and maximum colour changes of surface enamel was exhibited by Group 3. Scanning Electron Micrographs of Group 3 and Group 4 exhibited regular globular structures of enamel whereas Group 1 and Group 2 showed irregular globular surface of the enamel at 2000× and 5000× magnification. Maximum fluoride uptake on the surface enamel was seen in Group 4 followed by Group 3.

CONCLUSION

Use of LASER activated topical fluorides helps to achieve superior caries prevention. LASER activated APF can be used as an aesthetic alternative to SDF, as LASER activated APF showed higher uptake of fluoride on the enamel surface without discoloration effect.

Efficacy of ozonated water as a PS in photodynamic therapy: A tool for dental caries management? An in vitro study

Background

The most prevalent noncommunicable disease in the world is dental caries; and when it is not adequately treated, it is usually associated with tooth loss or severe dental lesions. In fact, expensive care or tooth extraction may be necessary due to the negative effects dental caries have on general health. This is due to its frequent pain and secondary bacterial infections. The aim of this study was to investigate the activity of ozonated water as such and in combination with appropriate light radiation so as to perform a photodynamic treatment (PDT) against the cariogenic bacterium Streptococcus mutans.

Design and methods

This work has been performed in vitro by using an S. mutans strain mainly structured in a biofilm status, reproducing the natural condition of the tooth infection. The ozone was tested at three different concentrations by using a commercial device able to generate different O3 formulations in water. The PDT treatment requires an appropriate light wavelength, evaluated in this work through the UV-Vis adsorption spectrum of the ozonated water.

Results

The obtained results suggested an effective and synergic property of O3 and light at 460-470 nm against this microorganism. The most antibiofilm activity was observed using a concentration of ozone of 0.06 mg/L alone as well as with PDT treatment.

Conclusions

The results are encouraging for additional research and in vitro/in vivo fresh experimental investigations to perform an exhaustive antimicrobial treatment protocol against the S. mutans tooth infection.

Acaricidal action of ozone on larvae and engorged females of Rhipicephalus microplus: a dose-dependent relationship

The tick Rhipicephalus microplus is a vector of infectious agents that causes great economic loss in the productivity of cattle herds. Several studies have sought natural compounds with acaricidal activity to control ticks, without allowing the development of resistance, without causing environmental damage, and without presenting toxicity to the hosts. The activity of ozone on the natural biomolecules of living beings has been studied as an alternative to control arthropods and acaricidal effects were shown on ticks. The aim of the present study was to assess the acaricidal effect on larvae and engorged females of R. microplus according to ozone dose. Larvae (n = 377) were distributed in 10 groups and engorged females (n = 284) were distributed in 14 groups. One group was used as control (not exposed to ozone) and the other groups were exposed to ozone gas for 5-105 min. Ozone had a dose-dependent acaricidal effect on both larvae and engorged females. Dosages between 355 and 2130 mg/L min had a delayed acaricidal effect (12-180 h), leading to the death of all engorged females before laying eggs, whereas doses between 3195 and 7455 mg/L min showed immediate acaricidal effect (5 min to 4 h). Doses between 1775 and 6390 mg/L min had an immediate (up to 5 min) acaricidal effect on the larvae of this species. Further studies should consider longer follow-up times during the assessment of the acaricidal activity against ticks.

The In Vitro, Ex Vivo, and In Vivo Effect of Edible Oils: A Review on Cell Interactions

Consumption of edible oils is a significant part of the dietary pattern in the developed and developing world. Marine and vegetable oils are assumed to be part of a healthy food pattern, especially if one takes into account their potential role in protecting against inflammation, cardiovascular disease, and metabolic syndrome due to the presence of polyunsaturated fatty acids and minor bioactive compounds. Exploring the potential effect of edible fats and oils on health and chronic diseases is an emerging field worldwide. This study reviews the current knowledge of the in vitro, ex vivo, and in vivo effect of edible oils in contact with various cell types and aims to demonstrate which nutritional and bioactive components of a variety of edible oils present biocompatibility, antimicrobial properties, antitumor activity, anti-angiogenic activity, and antioxidant activity. Through this review, a wide variety of cell interactions with edible oils and their potential to counteract oxidative stress in pathological conditions are presented as well. Moreover, the gaps in current knowledge are also highlighted, and future perspectives on edible oils and their health benefits and potential to counteract a wide variety of diseases through possible molecular mechanisms are also discussed.

Ozonated water as an irrigant in disinfecting root canal systems - a systematic review

Aim To evaluate the efficacy of ozonated water as an irrigant in disinfection of the root canal system.Materials and methods This systematic review was conducted according to PRISMA guidelines and methodological studies were assessed through the Cochrane Risk of Bias tool. All studies on extracted human teeth using ozonated water were considered for the study, whereas ex vivo studies, studies on animal dentition and studies which were published in languages other than English were excluded from the study. The search was carried out on various databases such as PubMed, Google Scholar and ScienceDirect within the last 15 years. The assessment of quality of the studies was performed under the following: 1) size of sample; 2) control group; 3) standardisation of procedure; 4) statistical analysis performed; 5) risk of bias.Results There were a total of 154 study results, out of which duplicates and full-text analysis were excluded. A total of seven studies were included in the systematic review. The results in one study by Cardoso et al. showed ozonated water was better at reducing microbial counts, while two other studies demonstrated the difference in reducing microbial counts when comparing ozonated water against other irrigants. The remaining four studies concluded that ozonated water did not perform better as compared to the other irrigants such as sodium hypochlorite and chlorhexidine.Discussion It could be concluded that ozonated water is not a better disinfecting irrigant than sodium hypochlorite and chlorhexidine in the disinfection of the root canal system; however, it had an almost comparable level of disinfection.

Potent Activity of a High Concentration of Chemical Ozone against Antibiotic-Resistant Bacteria

BACKGROUND

Health care-associated infections (HAIs) are a significant public health problem worldwide, favoring multidrug-resistant (MDR) microorganisms. The SARS-CoV-2 infection was negatively associated with the increase in antimicrobial resistance, and the ESKAPE group had the most significant impact on HAIs. The study evaluated the bactericidal effect of a high concentration of O3 gas on some reference and ESKAPE bacteria.

MATERIAL AND METHODS

Four standard strains and four clinical or environmental MDR strains were exposed to elevated ozone doses at different concentrations and times. Bacterial inactivation (growth and cultivability) was investigated using colony counts and resazurin as metabolic indicators. Scanning electron microscopy (SEM) was performed.

RESULTS

The culture exposure to a high level of O3 inhibited the growth of all bacterial strains tested with a statistically significant reduction in colony count compared to the control group. The cell viability of S. aureus (MRSA) (99.6%) and P. aeruginosa (XDR) (29.2%) was reduced considerably, and SEM showed damage to bacteria after O3 treatment Conclusion: The impact of HAIs can be easily dampened by the widespread use of ozone in ICUs. This product usually degrades into molecular oxygen and has a low toxicity compared to other sanitization products. However, high doses of ozone were able to interfere with the growth of all strains studied, evidencing that ozone-based decontamination approaches may represent the future of hospital cleaning methods.

Ozone in Patients with Periodontitis: A Clinical and Microbiological Study

The purpose of this article was to assess the effectiveness of ozone therapy as an adjunct to mechanical therapy in periodontitis patients. Thirty-two patients diagnosed with generalized periodontitis were selected, with a total of 655 teeth examined. Each patient’s mouth was divided into four quadrants (the split-mouth model) to be randomly treated with four sessions of gaseous ozone or air. The following clinical variables were recorded: the gingival index, the periodontal clinical attachment loss, the Miller’s mobility index and the clinical improvements, as assessed through the visual analog scale (VAS). In addition, the microorganisms were qualitatively compared. After four weeks of treatment, the teeth of the ozone-treated quadrants showed statistically significant reductions in the gingival index and an improvement in the clinical attachment (p < 0.0001). The same treatment also significantly improved mobility by between 70% and 86% compared to the control group (p < 0.0001). Statistically significant differences were also recorded for the VAS (p < 0.0001). In the qualitative study of the subgingival flora, significant differences were observed (p < 0.0001). The overall results of this trial support the view that ozone treatment is effective and well tolerated in cases of generalized chronic periodontitis.

Decomposition of Gaseous Styrene Using Photocatalyst and Ozone Treatment

Because photocatalysis has strong oxidation abilities in redox systems, it has been applied to indoor air purification. However, intermediate products are produced during the photocatalytic oxidative decomposition of aromatic compounds with benzene rings. Therefore, it is essential to improve decomposition performance and evaluate the intermediate products produced for practical applications. Herein, we describe the decomposition performance of ozone, photocatalyst, and their combination, under the target gas of styrene. Using a one-pass mini reactor, decomposition performance was evaluated by analyzing the output gas in the reactor and observing the styrene removal, the amount of carbon dioxide produced, and the composition of a small amount of intermediate products. The combination of ozone and photocatalyst showed the most significant performance, completely decomposing in the photocatalyst and removing odor components in ozone. Moreover, we demonstrated that decomposition performance could be evaluated by observing slight amounts of intermediate products in the exhaust gas. We believe that this research provides insights into the practical application of photocatalysis and ozone oxidation technologies in air purifiers and their performance management, with particular emphasis on the decomposition of odor compounds.

Antibacterial efficacy of copper-added chitosan nanoparticles: a confocal laser scanning microscopy analysis

The aim of this study was to evaluate the antibacterial efficacy of copper added chitosan nanoparticles (CU-CNPs) as an irrigation solution with different irrigants in terms of eliminating Enterococcus Faecalis (E. faecalis) from the root canals. Fifty mandibular premolar teeth were prepared and infected with E. faecalis for 21 days. After the incubation period, samples were randomly divided into a control group irrigated with distilled water and 4 experimental groups (n = 10) irrigated with as follows, %6 NaOCl, %6 NaOCl + %9 editronate (HEBP), Chitosan nanoparticles (CNPs), and CU-CNPs. To calculate the proportion of dead E. faecalis cell volume, stained using LIVE/DEAD BacLight Bacterial Viability Kit and were scanned using confocal laser scanning microscope (CLSM). All the irrigation solutions significantly (P < .05) killed the bacteria in the canal, except for the control group. CU-CNPs solution killed the highest (P < .05) number of bacteria compared with the other experimental groups. No significant difference was found between CNPs, NaOCl + HEBP, and NaOCl in terms of antibacterial activity. CU-CNPs solution was exhibited higher antibacterial efficacy against E. faecalis.

Effect of Cavity Disinfectants on Adhesion to Primary Teeth-A Systematic Review

Some authors have been proposing the use of cavity disinfectants in order to reduce, or even eliminate, the effect of the microorganisms present in a dental cavity before a restoration is placed. The aim of this study was to evaluate the effect of different cavity disinfectants on bond strength and clinical success of composite and glass ionomer restorations on primary teeth. The research was conducted using Cochrane Library, PubMed/MEDLINE, SCOPUS, and Web of Science for articles published up to February 2021. The search was performed according to the PICO strategy. The evaluation of the methodological quality of each in vitro study was assessed using the CONSORT checklist for reporting in vitro studies on dental materials. Sixteen in vitro studies and one in situ study fulfilled the inclusion criteria and were analyzed. Chlorhexidine was the most studied cavity disinfectant, and its use does not compromise dentin bonding. Sodium hypochlorite is a promising alternative, but more research on its use is required to clearly state that it can safely be used as a cavity disinfectant for primary teeth. Although other disinfectants were studied, there is a low-level evidence attesting their effects on adhesion, therefore their use should be avoided.

Morphophysiological analysis of the salivary glands of Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) exposed to ozonated water: A control strategy

The tick Rhipicephalus sanguineus sensu lato has great medical and veterinary importance, mainly because the ability to transmit many diseases, causing harm to pets but also risks to public health. The blood spoliation and transmission of pathogens occur because of the immunosuppressive action of these ticks' saliva, a potent mixture of bioactive substances that is secreted by the salivary glands, one of the organs responsible for their biological success, and hence the target of studies for their control. Ozone has promise for use as an alternative acaricide, due to its proven efficiency in controlling agricultural and food pests, besides posing no risk of environmental contamination or to animal and human health. Therefore, this study evaluated the acaricidal potential of exposure of females of R. sanguineus s.l. to ozonated water at many concentrations and analysed the morphophysiological alterations of the salivary glands, employing histological and light microscopic techniques. The results demonstrated that the ozonated water at the concentrations investigated caused severe alterations in the salivary glands, bringing a new perspective for control of R. sanguineus s.l., through an ecologically correct method due to the absence of harm to non-target organisms and the environment.

Comparative evaluation of antibacterial efficacy of Allium sativum extract, aqueous ozone, diode laser, and 3% sodium hypochlorite in root canal disinfection: An in vivo study

Aim:

The present study aimed to individually evaluate and compare the aerobic and anaerobic antibacterial activity of Allium sativum extract, aqueous ozone, diode laser, and 3% sodium hypochlorite (NaOCl) as root canal irrigants.

Materials and Methods:

Forty-eight patients were selected and randomly allocated to one of the four groups (n = 12 each) according to the irrigant to be used in each group. For each included tooth, the preirrigation and postirrigation (after irrigation with the test solution) samples were collected through sterile paper points and microbial culturing was done by swabbing on blood agar plates followed by incubation for aerobic and anaerobic bacteria.

Statistical Analysis:

Manual colony-forming units counting were done, and statistical analysis was performed. Analysis of variance (one-way) followed by post hoc test was performed as a parametric test to compare the difference between the groups for both aerobic and anaerobic bacteria.

Results:

All the groups showed a statistically significant reduction in bacteria (P < 0.05). However, between the groups, the maximum reduction was seen with 3% NaOCl followed by diode laser, A. sativum extract, and least by aqueous ozone.

Conclusion:

A. sativum extract, aqueous zone, diode laser, and 3% NaOCl showed significant antibacterial activity against aerobic and anaerobic bacteria.

Application of Selected Nanomaterials and Ozone in Modern Clinical Dentistry

This review is an attempt to summarize current research on ozone, titanium dioxide (TiO₂), silver (Ag), copper oxide CuO and platinum (Pt) nanoparticles (NPs). These agents can be used in various fields of dentistry such as conservative dentistry, endodontic, prosthetic or dental surgery. Nanotechnology and ozone can facilitate the dentist’s work by providing antimicrobial properties to dental materials or ensuring a decontaminated work area. However, the high potential of these agents for use in medicine should be confirmed in further research due to possible side effects, especially in long duration of observation so that the best way to apply them can be obtained.

Cytotoxicity assessment of different doses of ozonated water on dental pulp cells

Background

The purpose of this study was to assess the cytotoxicity of various concentrations of ozonated water (OW) on human primary dental pulp cells.

Methods

Human primary dental pulp cells were isolated from exfoliated primary canine teeth of an 11-year-old patient with good systemic and oral health. Afterwards, cells were divided into 6 experimental groups; four groups of OW in concentrations of 2 mg/L, 4 mg/L, 8 mg/L, and 16 mg/L, untreated control group, and cell culture without cells. Cytotoxicity was evaluated after exposure for 5-min exposure using Mosmann’s Tetrazolium Toxicity (MTT) assay at 0 h and 48 h time points. Data were analyzed using a repeated measures analysis of variance and Post-hoc tests were performed using Bonferroni correction for multiple comparisons.

Results

All experimental groups showed proliferation at 0 h time point. However, all groups also experienced a decrease in overtime at 48 h time point (p < 0.05). At both time points 2 mg/L OW showed the highest cell viability as well as proliferation. At 0 h time point, the increase in cell viability for all experimental groups was found statistically significant when compared to positive control group (p < 0.05). At 48 h time point, although 8 mg/L and 16 mg/L OW showed statistically significant reduction in compare to 0 h time point, 2 mg/L and 4 mg/L OW groups didn’t experience any statistically significant difference (p < 0.05).

Conclusion

Considering our findings, due to ozonated water's induced a higher proliferation rate of dental pulp cells, indicating their biocompatibility and a possible adjuvant on irrigating agent in regenerative endodontic procedures.

The Combination of Diode Laser and Ozonated Water in the Treatment of Complicated Pulp Gangrene

The study aimed to investigate the effects of endodontic space decontamination using a laser combined with ozonated water in the therapy of complicated pulp gangrene. The subject of this in vivo study was a 12-year-old patient diagnosed with extensive periapical periodontitis on the mandibular right first molar. Biological samples were initially collected to identify the active pathogen—Enterococcus faecalis, then the nonsurgical endodontic treatment was performed in a single visit, according to the active disinfection guidelines of the identified pathogen. Two-month postoperative, clinical and radiological examination revealed a complete healing of the periapical lesion. The correct diagnosis of this endodontic–periodontal pathology, and the unconventional treatment of the complex system of infected root canals, allowed a favorable treatment result without any surgical intervention. This unconventional approach, which combines a laser technique with ozonated water, allows for predictable results in periapical lesion treatment.

[Advanced research on root canal therapy for primary teeth]

Primary tooth root canal therapy is a treatment performed on primary teeth diagnosed with pulpitis or periapical periodontitis. This procedure requires perfect instrumentation, disinfection, and filling of root canals to eliminate infection, control inflammation, relieve pain, prevent pathological effects on inherited permanent tooth, and prolong primary tooth preservation. This paper reviews the research history on primary tooth root canal treatment and summarizes the progress on primary tooth root canal treatment, including anatomical morphology, root canal preparation, root canal disinfection, root canal filling, and application of antibiotics.

Antibacterial Efficacy of Sodium Hypochlorite, Ozonated Water, and 980 nm Diode Laser Used for Disinfection of Root Canal against Enterococcus faecalis: A Microbiological Study

Aim

Evaluation and comparison of the antibacterial efficacy of sodium hypochlorite, ozonated water, diode laser, and diode laser in combination with ozonated water against Enterococcus faecalis.

Materials and methods

One hundred and twenty extracted premolar teeth were sectioned at the cementoenamel junction and root canals were prepared using step-back technique with K-file up to #40. The teeth were arbitrarily allocated to four groups and stowed into brain heart infusion broth containing a microbial suspension of E. faecalis. Group I samples were irrigated with 3% sodium hypochlorite. Group II samples were irrigated with ozonated water. Group III samples were irrigated firstly by distilled water followed by laser irradiation. Group IV samples were irrigated by ozonated water followed by laser irradiation. After the treatment, the teeth were kept in vials containing 2 mL of nutrient broth. The vials were then incubated at 37°C for 24 h. Standard methods were then used to identify grown colonies.

Statistical analysis

Kruskal–Wallis test, Mann–Whitney test, Chi-square test, and Wilcoxon signed-rank test were used to measure the colony-forming units (CFUs) obtained at the end of the incubation period among the various groups for the evaluation of antibacterial efficacy of various disinfection protocols.

Results

The highest mean CFU/mL is recorded in group II (with ozonated water) followed by group I (with sodium hypochlorite), group III (with a laser), and the least mean CFU/mL is seen in group IV (with laser and ozonated water). The variation in CFU/mL among the three groups is statistically significant (p < 0.05).

Conclusion

The outcome of this study reveals that 980 nm diode laser along with ozonated water when used together can eliminate and disinfect the root canals with E. faecalis.

How to cite this article

Kushwah J, Mishra R, Bhadauria V. Antibacterial Efficacy of Sodium Hypochlorite, Ozonated Water, and 980 nm Diode Laser Used for Disinfection of Root Canal against Enterococcus faecalis: A Microbiological Study. Int J Clin Pediatr Dent 2020;13(6):694–699.

The effect of ozone therapy in root canal disinfection: a systematic review

AIM

To answer the following focused question: 'As regards microorganism load reduction for patients undergoing root canal treatment, is the use of ozone therapy comparable to conventional chemomechanical techniques using sodium hypochlorite (NaOCl)?'

DATA SOURCES

A systematic review was conducted using controlled vocabulary and free-text key words in the following databases: PubMed, Science Direct, Scopus, Web of Science and Open Grey until 2 November 2018. Additional studies were sought through hand searching of endodontic journals.

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS

The inclusion criteria comprised studies that compared microbial reduction in root canals after treatments with ozone and NaOCl in extracted mature human teeth or randomized clinical trials.

STUDY APPRAISAL AND SYNTHESIS METHODS

The quality assessment of included laboratory studies was performed with the following parameters: (i) sample size calculation, (ii) samples with similar dimensions, (iii) control group, (iv) standardization of procedures, (v) statistical analysis and (vi) other risk of bias. For randomized clinical trials, the qualitative analysis of the studies was performed from the bias risk assessment using the tool 'Bias Risk Assessment of Randomized Controlled Studies' Cochrane Handbook 5.0.2.

RESULTS

The search resulted in 180 published studies. After removal of duplicate studies and full-text analysis, eight studies were selected and seven were considered low risk of bias (seven ex vivo studies and one random clinical trial). Overall, the results demonstrated that ozone therapy provides significantly less microbial load reduction than NaOCl. As an adjunct in chemomechanical preparation, ozone was ineffective in increasing the antimicrobial effect of NaOCl. Ozone performance was strongly associated with the application protocol used: it is dose, time and bacterial strain dependent, besides the correlation with the use of complementary disinfection sources.

LIMITATIONS

A restricted number of randomized clinical trial was found, and the difference amongst the methodology of the studies did not allow a meta-analysis to be performed.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Although the selected studies had limitations, this review reached a satisfactory methodological and moderate evidence quality contributing to important preliminary information regarding ozone therapy. As regards load reduction of microorganisms for patients undergoing root canal treatment, ozone is not indicated neither to replace nor to complement the antimicrobial action of NaOCl.

Cytotoxicity evaluation of a new ozonized olive oil

Objective:

The cytocompatibility of a new ozonized olive oil toward immortalized human gingival fibroblasts (HGFs) was evaluated and compared with two common antimicrobial agents based on chlorhexidine digluconate (CHX).

Materials and Methods:

The cytocompatibility of the samples was tested on immortalized HGF-1 cells by 3-(4, 5-dimethyl thiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay. The cells were incubated for 2 or 24 h with increasing dilution of ozonized olive oil or CHX agents. The percentage of viable cells was calculated relative to control cells set to 100%.

Results:

The ozonized olive oil is cytocompatible, and the viability values of the cells treated for 2 or 24 h with increasing concentrations of ozonized olive oil were significantly higher (P < 0.01) compared with the values obtained using CHX.

Conclusions:

The present data demonstrate that due to its cytocompatibility, the new ozonized olive oil could be considered an alternative antibacterial agent.

Effectiveness of the ozone application in two-visit indirect pulp therapy of permanent molars with deep carious lesion: a randomized clinical trial

OBJECTIVES

The aim of this randomized, three-arm parallel, single-blinded clinical trial was to evaluate the clinical and microbiological effectiveness of the ozone application in two-visit indirect pulp therapy.

MATERIALS AND METHODS

One hundred five lower first molar teeth with deep caries lesion were included and randomly assigned three groups to apply the two-visit indirect pulp therapy. Treatment procedure was applied without any disinfectant (control), with 60-s 2% chlorhexidine digluconate (CHX) or 60-s ozone application. In four different stages (after initial excavation, ozone/CHX application before the temporary restoration, 4 months later immediately after removing temporary restoration, and final excavation), dentin humidity, consistency, and color properties were recorded to evaluate the clinical characteristics of the tissue, and standard dentin samples were collected for the microbiological analysis of mutans streptococci, lactobacilli, and the total number of colony-forming units. The data were analyzed by using Mann-Whitney U test for multiple comparisons.

RESULTS

The remaining dentin became harder, drier, and darker after 4 months in all groups. However, CHX and ozone application were statistically better than the control group (p < 0.05). There was a gradual decrease in the total number of microorganisms in all groups. While cavity disinfectant applications were improved the antibacterial efficacy (control, 79.11%; CHX, 98.39%; ozone, 93.33%), CHX application exhibited a greater significant reduction than both groups (p = 0.000).

CONCLUSION

The two-visit indirect pulp therapy yielded successful results for all study groups. However, CHX would be conveniently preferable due to improving the treatment success.

CLINICAL RELEVANCE

The two-visit indirect pulp therapy applied with cavity disinfectant is a proper alternative treatment procedure in deep carious lesions, instead of conventional technique.

Endodontic biofilms: contemporary and future treatment options

Apical periodontitis is a biofilm-mediated infection. The biofilm protects bacteria from host defenses and increase their resistance to intracanal disinfecting protocols. Understanding the virulence of these endodontic microbiota within biofilm is essential for the development of novel therapeutic procedures for intracanal disinfection. Both the disruption of biofilms and the killing of their bacteria are necessary to effectively treat apical periodontitis. Accordingly, a review of endodontic biofilm types, antimicrobial resistance mechanisms, and current and future therapeutic procedures for endodontic biofilm is provided.

Evaluating clinical and laboratory effects of ozone in non-surgical periodontal treatment: a randomized controlled trial

OBJECTIVE

This study aims to evaluate the clinical and biochemical (oxidative stress and pro-inflammatory mediators) effects of the gaseous ozone use accompanied by scaling and root planning (SRP) in periodontal treatment.

MATERIAL AND METHODS

The study population consisted of 40 patients with chronic periodontitis (CP) randomly sorted into two groups of 20. The experimental group received SRP plus 3 watts gaseous ozone in two separate applications five days apart, whereas the control group received SRP plus placebo. Clinical periodontal parameters were assayed and saliva samples were taken before the initial and one month after the second treatment. Periodontal examination assessed plaque index (PI), gingival index (GI), probing depth, and clinical attachment level (CAL). Total antioxidant status (TAS), total oxidant status (TOS), nitric oxide (NO), 8-hydroxy-2'-deoxyguanosine (8-OHdG), myeloperoxidase (MPO), glutathione (GSH), malondialdehyde (MDA), and transforming growth factor-beta (TGF-β) levels were evaluated from saliva samples.

RESULTS

Changes following treatment in PI, GI, probing depth, and CAL scores were similar for both groups (p>0.05). Of note, TGF-β levels were observed to be higher in the treatment group than in controls (p<0.05). Changes in 8-OHdG, TAS, TOS, NO, MPO, GSH and MDA levels, however, were not significantly different between groups (p>0.05).

CONCLUSION

The findings of this study indicate that SRP plus gaseous ozone versus SRP alone does not correlate to a significant improvement in periodontal recovery.

Evaluation of the antibacterial activity of a new ozonized olive oil against oral and periodontal pathogens

Background

In the present study, the antimicrobial properties of a new ozonized olive oil (O-zone gel) against oral and periodontal pathogens will be evaluated and compared with that of common CHX-based agents.

Material and Methods

O-zone gel was compared with two agents based on chlorhexidine digluconate (CHX): Corsodyl Dental Gel and Plak Gel. A. actinomycetemcomitans, P. intermedia and S. mutans, were selected and the antibacterial capability of the compounds was tested by using direct contact agar diffusion test (DCT) and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) evaluations. Differences between specific means were analyzed by a one-way analysis of variance (ANOVA). Group means were compared using a one-way ANOVA and Tukey’s test (P<0.05).

Results

O-zone gel reported inhibition zones which correspond to 33% and 43% of that achieved by the CHX agents. No inhibition of bacterial growth (MIC) on the Gram-positive strain by using O-zone gel was found and no antimicrobial effect (MBC) was observed by using O-zone gel on both Gram-negative and -positive strains.

Conclusions

The new ozonated oil was a relatively moderate antiseptic. Gram-negative bacteria proved to be more sensitive to ozonized olive oil than Gram-positive ones. The ozonized olive oil demonstrated a lower antibacterial activity if compared to the CHX-based agents tested.

Key words:Agar diffusion test, antibacterial activity, direct contact test, ozone, ozonized olive oil.

Bactericidal Effect of Various Laser Irradiation Systems on Enterococcus faecalis Biofilms in Dentinal Tubules: A Confocal Laser Scanning Microscopy Study

OBJECTIVE

The aim of this study was to compare the bactericidal effect of various laser irradiation systems on Enterococcus faecalis biofilms in dentinal tubules by using a novel dentin infection model and confocal laser scanning microscopy (CLSM).

BACKGROUND DATA

Laser-activated irrigations have been proposed as an adjuvant to conventional protocols of root canal treatment to enhance the smear layer removal, which is a promising protocol for root canal disinfection.

MATERIALS AND METHODS

E. faecalis were centrifuged into the dentinal tubules, cultured for 3 weeks, and then received 1- and 3-min treatments as follows: (A) 5.25% sodium hypochlorite (NaOCl) irrigation, (B) Nd:YAG laser irradiation, (C) diode laser irradiation, (D) Nd:YAP laser irradiation, (E) Er,Cr:YSGG laser-activated NaOCl irrigation, and (F) Er:YAG laser-activated NaOCl irrigation. Bacterial reductions were assessed by CLSM using a LIVE/DEAD^® bacterial viability stain method.

RESULTS

For each group, the bacterial reduction increased as the treatment time increased (p < 0.05). The Er,Cr:YSGG and Er:YAG laser significantly enhanced the bactericidal effect of NaOCl (p < 0.05). Under the conditions of the same treatment time, bacterial reductions were presented in the descending order of Er:YAG + NaOCl, Er,Cr:YSGG + NaOCl > Nd:YAP > Nd:YAG, diode > NaOCl.

CONCLUSIONS

Under the conditions of present study, treatments of Er:YAG + NaOCl and Er,Cr:YSGG + NaOCl presented the strongest bactericidal effect among the tested protocols and are potential protocols for root canal disinfection.

In Search of a Novel Substitute: Clinical and Radiological Success of Lesion Sterilization and Tissue Repair with Modified 3Mix-MP Antibiotic Paste and Conventional Pulpectomy for Primary Molars with Pulp Involvement with 18 Months Follow-up

Objectives:

The aim of this study was to evaluate the clinical and radiographic success of zinc oxide (ZnO)-ozonated oil, modified 3Mix antibiotic paste, and vitapex in the treatment of primary molars requiring pulpectomy.

Methods:

Sixty-four primary molars of forty-three healthy children aged between 4 and 8 years with primary molars requiring root canal procedure were treated with ZnO-ozonated oil, modified 3Mix-MP antibiotic paste, and vitapex. Clinical follow up was done at 1, 6,12 months and 18 months while radiographical follow-up was done at 6,12 and 18 months, respectively.

Results:

The results showed that the clinical success rates of ZnO-ozonated oil, modified 3Mix-MP paste and vitapex were 95.5%,89.5% and 100% respectively and radiographical success rates were 94.4%,80.95% and 100% respectively after 18 months period of observation.

Conclusion:

The overall success rates of ZnO-ozonated oil, vitapex and modified 3Mix antibiotic paste were comparable.

Comparison of the Antimicrobial Efficacy of the EndoVac System and Conventional Needle Irrigation in Primary Molar Root Canals

PURPOSE

The purpose of this study was to compare the antimicrobial efficacy of the EndoVac system and conventional needle irrigation to eliminate E faecalis in primary molar root canals.

STUDY DESIGN

60 extracted human primary second molar roots were instrumented up to an apical size .04/35 and randomly divided into two groups; Group 1: conventional needle (n=30) and Group 2: EndoVac (n=30), and four subgroups (two experimental subgroups; (a) 2.5% sodium hypochlorite (NaOCl) + ethylenediaminetetraacetic acid (EDTA) (n=20), (b) ozonated water (OW) + EDTA (n=20), and control groups (c) 5.25% NaOCl (n=10) and (d) saline (n=10). All roots were sterilized and then inoculated with E.faecalis. Before and after final irrigation procedures, root canals were sampled and the grown colony forming units (CFUs) were counted. Data were analyzed by Kruskall-Wallis and Mann-Whitney U tests using a 0.05 significance level.

RESULTS

The EndoVac reduced more bacteria than the conventional needle did but it was not statistically significant (p>0.05). NaOCl alone or followed by EDTA totally eliminated bacteria. OW + EDTA showed higher reduction of bacteria but could not totally eliminate bacterias.

CONCLUSIONS

In the context of bacterial elimination, the EndoVac was not significantly better than the conventional needle. Although, there were fewer CFU/mg when using EndoVac, there was not any statistically significant superiority to conventional needle irrigation. An OW+EDTA regimen showed antibacterial effect in the primary molar root canals but it was significantly less effective than NaOCl+EDTA.

Antibacterial Activity of Freshly Prepared Ozonated Water and Chlorhexidine on Mutans Streptococcus When Used as an Oral Rinse - A Randomised Clinical Study

INTRODUCTION

Dental caries is one of the most common causes of morbidity of the tooth. Attempts have been made to reduce the pathogen population size i.e., Mutans Streptococci (MS) to demote the incidence of caries and increase the resistance of the tooth to cariogenic attack.

AIM

To evaluate the antibacterial efficacy of freshly prepared ozonated water, in proposing it as an alternative mouth rinse on MS in comparison to Chlorhexidine (CHX).

MATERIALS AND METHODS

Subjects with high caries incidence and MS counts more than 105 Colony Forming Unit (CFU) were selected and divided by block randomization into two groups of 23 subjects each. The subjects were advised to use the respective mouth rinses under the operator surveillance, consecutively for 14 days. Stimulated salivary samples were collected from the subjects on the first day, 7^th and 14^th day to analyse the changes in MS counts during the course of use of oral rinses. The obtained data was tabulated and statistically analysed.

RESULTS

Freshly prepared ozonated water showed a statistically significant reduction in MS counts after an interval of 7 days and 14 days when compared to CHX.

CONCLUSION

Ozonated water when consecutively used as a mouth rinse resulted in a significant reduction of MS counts. Hence, it can be used as an alternative to chlorhexidine.

Ozone Gas Effect on Mineral Content of Dentin exposed to Streptococcus mutans Biofilm: An Energy-dispersive X-ray Evaluation

AIM

This study aims to assess the effect of ozone gas on dentin exposed to Streptococcus mutans biofilm by evaluation of mineral content [log calcium-to-phosphorus (Ca/P)] using energy-dispersive X-ray (EDX) spectroscopy.

MATERIALS AND METHODS

Five human third molars were sectioned into four slices of dentin and distributed in four groups: I - control (no treatment); II - ozone therapy; III - biofilm development; IV - ozone therapy followed by biofilm development. Mineral content (log Ca/P) was evaluated by EDX. Data were analyzed by analysis of variance and Tukey's test (p < 0.05).

RESULTS

Results showed that the mineral content of control group (I) was similar to ozone group (II), and was statistically higher than biofilm (III) and ozone + biofilm (IV). The lowest log Ca/P was determined in biofilm group (III).

CONCLUSION

It can be concluded that ozone gas did not grant preventive effects of demineralization by S. mutans biofilm on dentin surface.

CLINICAL SIGNIFICANCE

Ozone gas therapy may be an alternative noninvasive treatment aiming to reduce the levels of caries-associated microorganisms. This therapy may, thereby, be an alternative and/or complementary treatment strategy in preventive dentistry.

Ozone therapy as an adjuvant for endondontic protocols: microbiological - ex vivo study and citotoxicity analyses

Objectives

This study evaluated the antimicrobial efficacy of ozone therapy in teeth contaminated with Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus using a mono-species biofilm model. Parallel to this, the study aimed to evaluate the cytotoxicity of ozone for human gingival fibroblasts. Material and Methods: One hundred and eighty single-root teeth were contaminated with a mono-species biofilm of Enterococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus. Groups were formed: Group I - control; Group II - standard protocol; Group III - standard protocol + ozone gas at 40 µg/mL; and Group IV - standard protocol + aqueous ozone at 8 µg/mL. In parallel, human gingival fibroblasts were submitted to the MTT test. Cells were plated, then ozone was applied as follows: Group I (control) - broth medium; Group II - aqueous ozone at 2 µg/mL; Group III - aqueous ozone at 5 µg/mL; and Group IV - aqueous ozone at 8 µg/mL. Data were submitted to the Kruskal Wallis test and Bonferroni post hoc analyses to assess microbiology and cytotoxicity, respectively (p<0.05%).

Results

The results revealed antimicrobial efficacy by Group IV with no CFU count. The cytotoxicity assay showed Groups III and IV to be the most aggressive, providing a decrease in cell viability at hour 0 from 100% to 77.3% and 68.6%, respectively. Such a decrease in cell viability was reverted, and after 72 hours Groups III and IV provided the greatest increase in cell viability, being statistically different from Groups I and II.

Conclusion

According to the applied methodology and the limitations of this study, it was possible to conclude that ozone therapy improved the decontamination of the root canal ex vivo. Ozone was toxic to the cells on first contact, but cell viability was recovered. Thus, these findings suggest that ozone might be useful to improve root canal results.

Antimicrobial activity of ozone and NaF-chlorhexidine on early childhood caries

An early childhood carie (ECC) is an extremely destructive form of tooth decay. The aim of this study was to investigate the action of ozone (O3), and the association of sodium fluoride (NaF) with chlorhexidine (CHX) on bacteria related to ECC. Overnight culture of the bacteria was performed. On exponential phase the suspension was adjusted (101-108 CFU/mL). A drop (10μL) of each concentration of bacteria was applied on sheep blood agar plates and treated with O3 (2, 20, 200, and 2,000 ppm); after 18 hours, recovery analysis of CFU verified the reduction of bacterial activity. For NaF-CHX, sterile 96-well plates were prepared and divided into groups: G1 (150 µL TSB); G2 (20 µL of bacteria + 25 µL CHX + 25 µL NaF); and G3 (150 µL TSB + 20 µL of bacteria + 50 µL water). The plates were verified by analysis of the optical density (0, 12, 14, 16, and 18 hours). The data from O3 test were submitted to ANOVA and Tukey's test (p < 0.05). For the data from NaF-CHX, the ANOVA 2-way and Bonferroni's test (p < 0.05) were used. The number of CFU/mL showed death > 3log10 (99.9%) for all bacteria (ozone ≥ 20ppm), while the combination of NaF-CHX was more effective (p < 0.001) compared to each substance tested alone and the control group. The antimicrobial agents tested were able to inhibit all bacteria tested; O3 seemed to be a good alternative for controlling progression of carious lesions, while the association of NaF-CHX showed to be a good antimicrobial with easy and inexpensive application.

Ozone- A Biological Therapy in Dentistry- Reality or Myth?????

The usage of ozone in dentistry has been proposed because of its antimicrobial, disinfectant, biocompatibility and healing properties. In the last decade a number of therapeutic protocols with ozone have been developed to address common dental infections associated with periodontal disease, RCT and caries. Despite these advantages, therapeutic ozone's application in dentistry is limited because of its possible side effects. Hence, dental practitioners need to know the proper usage of ozone therapy that can provide better patient care and considerably cut down the time and cost of the treatment.

Effect of gaseous ozone and light-activated disinfection on the surface hardness of resin-based root canal sealers

Although root canal instruments remove most of the content from the main root canal space, disinfection or irrigation plays an indispensable role in all areas of the root canal system, especially in parts that are inaccessible by instruments. The originality of this study was to investigate the effect of two novel disinfection techniques on the surface hardness of resin-based endodontic sealers using atomic force microscopy (AFM). Forty extracted single-rooted maxillary central human teeth were prepared and divided into four groups according to treatment methods. The first group was irrigated with saline and served as a control, other groups irrigated with sodium hypochlorite (NaClO); gaseous ozone; and light-activated disinfection (LAD). The groups were divided into two subgroups, according to the obturation method used: subgroup A: gutta-percha and AH plus; and subgroup B: EndoREZ/resin-coated cones. After obturation, atomic force microscopy (AFM) measurement was performed to analyze the surface hardness of the sealers. There was a significant difference between group 1A and group 3A (p < 0.05). Group 3B had the highest surface hardness values that were statistically different (p < 0.05). When disregarding the sealers, the ozone possessed statistically higher surface hardness values than the other groups in all root thirds (p < 0.05). The use of ozone and LAD may alter the surface hardness of resin-based sealers. The use of AFM can be considered an alternative hardness test techonology for sealing material.

Effect of ozonated oil and chlorhexidine gel on plaque induced gingivitis: A randomized control clinical trial

BACKGROUND

Several chemotherapeutic agents have been developed to prevent gingivitis and its progression into periodontitis. In this present study, the efficacy of ozonated oil and chlorhexidine gel was assessed and compared on plaque induced gingivitis.

AIM

To evaluate the effect of ozonated oil on plaque induced gingivitis and to compare its efficacy with chlorhexidine gel.

MATERIALS AND METHODS

A total of 20 subjects, aged from 18 to 65 years, with plaque-induced gingivitis were selected from the outpatient Department of Periodontology, Government Dental College and Hospital, Aurangabad, for this study. They were divided randomly into the test or ozonated oil group (Group I) and the control or chlorhexidine gel group (Group II) with 10 subjects in each group. Subjects were randomly assigned to massage their gingiva thrice a day for 3 weeks with ozonated oil (test), and chlorhexidine gel (control). Plaque index and gingival index scores were recorded for the 20 subjects at baseline and after 3 weeks.

RESULTS

Ozonated oil (Group I) and chlorhexidine gel (Group II) groups showed statistically significant differences with respect to plaque index and gingival index, from the baseline to 3 weeks (P < 0.001 in both). But the difference between Group I and Group II, at the end of the study period, was not statistically significant with respect to the plaque index and gingival index.

CONCLUSIONS

The ozonated oil and chlorhexidine gel, both can be used as an effective agent in maintaining and improving gingival health.

Effect of gaseous ozone on Enterococcus faecalis biofilm-an in vitro study

OBJECTIVES

The aim of this study was to evaluate the antimicrobial effect of gaseous ozone compared to conventional methods against Enterococcus faecalis.

MATERIALS AND METHODS

One hundred twenty-five teeth were infected by E. faecalis and were incubated for 72 h to form biofilm. Teeth were distributed among five groups. In the first group, ozone was used; in the second group, teeth were rinsed with 20 % ethylenediaminetetraacetic acid (EDTA); in the third group, with 3 % sodium hypochlorite (NaOCl). Group 4 combined 20 % EDTA with ozone. NaOCl and ozone were combined in group 5. After treatment, the samples with paper points were taken, followed by dentin samples taken with K-file, and cultured for 24 h. Then bacterial colonies were counted.

RESULTS

All treatments reduced significantly (p < 0.05) the bacteria. Paper points' samples showed 85.38 % reduction after ozone. The highest reduction was observed in NaOCl group (99.98 %). EDTA reduced bacteria by 80.64 %. Combination of NaOCl and ozone eradicated 99.95 % of the bacteria. Combination of EDTA and ozone reduced E. faecalis up to 91.33 %. The dentin chips showed the following: the highest CFU counts were observed in EDTA group, followed by ozone and NaOCl group. The lowest CFU counts were found in NaOCl-ozone group and EDTA-ozone group.

CONCLUSIONS

Ozone reduced E. faecalis, even organised in a biofilm, however, lower than NaOCl. No treatment reduced totally the bacteria.

CLINICAL RELEVANCE

Used as an adjuvant, ozone can increase the efficacy of conventional rinsing like EDTA and presents an alternative treatment when NaOCl cannot be used e.g. in teeth with a wide-open apical foramen.