Methods for SARS-CoV-2 hospital disinfection, in vitro observations

Introduction

Escalation of chemical disinfection during the COVID-19 pandemic has raised occupational hazard concerns. Alternative and potentially safer methods such as ultraviolet-C (UVC) irradiation and ozone have been proposed, notwithstanding the lack of standardized criteria for their use in the healthcare environment.

Aim

Compare the virucidal activity of 70% ethanol, sodium dichloroisocyanurate (NaDCC), chlorhexidine, ozonated water, UVC-222 nm, UVC-254 nm against three SARS-CoV-2 variants of concern cultured in vitro.

Methods

Inactivation of three SARS-CoV-2 variants (alpha, beta, gamma) by the following chemical methods was tested: ethanol 70%, NaDCC (100 ppm, 500 ppm, 1000 ppm), chlorhexidine (2%, 1% and 0.5%), ozonated water 7 ppm. For irradiation, a je2Care 222nm UVC Lamp was compared to a Sylvania G15 UV254 nm lamp.

Results

Viral inactivation by >3 log was achieved with ethanol, NaDCC and chlorhexidine. The minor virucidal effect of ozonated water was <1 log. Virus treatment with UVC-254 nm reduced viral activity by 1-5 logs with higher inactivation after exposure for 3 minutes compared to 6 seconds. For all three variants, under equivalent conditions, exposure to UVC-222 nm did not achieve time-dependent inactivation as was observed with treatment with UVC-254 nm.

Conclusion

The virucidal activity on replication-competent SARS-CoV-2 by conventional chemical methods, including chlorhexidine at concentrations as low as 0.5%, was not matched by UVC irradiation, and to an even lesser extent by ozonated water treatment.

Ozonation for Pseudomonas paracarnis control: biofilm removal and preservation of chicken meat during refrigerated storage

Ozone has been studied to control microorganisms in food, as well as to control biofilm. In this context, the goals of this work were to determine the effect of ozonated water in the removal of Pseudomonas paracarnis biofilm and the effect of ozone gas and ozonated water on inactivating P. paracarnis in deboned chicken breast meat and its effect on product color. AISI 304 coupons were used as a surface for biofilm formation. The coupons were immerged into minimal medium for Pseudomonas inoculated with the P. paracarnis overnight culture (1% w/v) followed by incubation at 25 °C for 7 days. To obtain ozonized water, two different systems were used: system with microbubble generator (MB) and system with porous stone diffuser (PSD). The inlet ozone concentration was 19 mg/L and flow rate of 1 L/min. The coupons were subjected to ozonized water for 10 and 20 min. The chicken breast meat was exposed to gaseous ozone and ozonized water for 40 min. After the ozonation process, chicken meat samples were stored at 8 °C, for 5 days. More expressive removals of biofilm were obtained when using ozonized water obtained in the system with microbubble generator (MB for 20 min-reduction of 2.3 log cycles) and system with porous stone diffuser (PSD for 10 min-reduction of 2.7 log cycles; PSD for 20 min-reduction of 2.6 log cycles). The treatment of chicken meat with ozone gas resulted in lower counting of Pseudomonas, when compared with the control treatments and with ozonized water, both immediately after ozonation (day 1) and after 5 days of storage. The luminosity in the chicken meat samples treated with ozonized water was higher than that verified in the control treatments and with ozone gas, immediately after ozonation (day 1). A similar trend was observed in hue angle and color difference, in which the highest values were obtained for treatment with ozonized water. Based on the results obtained in this study, it was concluded that ozonated water can be used to remove P. paracarnis biofilm from stainless steel under static conditions and gaseous ozone is more efficient in the inactivation of P. paracarnis from chicken breast meat, when compared to ozonated water.

The adhesive strength of fiber post-to-canal dentin with Aniline green, Fotoenticine activated by PDT, green tea, and ozone as a final irrigant

AIM

The effect of novel final disinfection protocols Malachite green (MG), Fotoenticine® (FTC), Green tea extract (GTE), and Ozonated water (OW) on the bond strength of prefabricated glass fiber posts (PGFP) adhered to canal dentin.

MATERIAL AND METHOD

The canals of fifty premolars with closed apices were cleansed and obturated. The specimens were randomly assigned to one of five groups based on the final irrigant used, with the control group receiving NaOCl+EDTA and the experimental groups receiving MG, FTC, OW, and GTE. The GFP was cemented with a self-etching, dual-cure paste; the bond strength was estimated with a universal testing machine; and failure analysis was conducted with a stereomicroscope.

RESULTS

The highest PBS was observed in the coronal third of Group 4 (using ozonated water as the final irrigant), whereas the lowest bond integrity was observed in the apical section of Group 2 (1.02-0.54 MPa) using Malachite green as the final irrigant. Group 1, Group 4, and Group 5 exhibited no significant difference in the bond integrity of GFP to dentin when compared to Group 2 (p>0.05). In addition, comparable bond score values were obtained for Groups 2 and 3 (p>0.05).

CONCLUSION

The results of this study suggest that OW and GTE may be effective final disinfectants for root canals, as they increase the bond strength of resin-luting cement.

Comparison of ozonated water and acidified copper sulphate in prevention of digital dermatitis in dairy cows

Digital dermatitis (DD) is the most significant infectious hoof disorder of cattle in Europe. Hoof baths are one of the most common control methods. Copper sulphate and formalin are commonly used in hoof baths, but their use is problematic in many European countries for health, environmental and safety reasons. Ozonated water and acidified copper sulphate were tested as prevention of DD in a 5-month study. Data were derived from 302 hind feet of Holstein and Estonian Red cows (no. of cows = 151) from a commercial dairy farm in Estonia. Altogether 168 hind feet were included in the acidified copper sulphate group and 134 feet in the ozonated water group. Hoof bathing was carried out three days a week (Mon, Wed, Fri) for two months and then two days a week (Mon, Wed) for three and a half months, in both groups. Ozonated water was sprayed on to the digital skin of hind feet of cows twice a day on treatment days, while the cows were eating. The copper sulphate bath consisted of copper sulphate (2%) mixed with an organic acid compound to acidify and ionize the solution. Cows walked through acidified copper sulphate solution twice a day on treatment days as they were exiting the milking parlor. DD negative and DD positive test results in both groups were compared and statistically tested for differences. The copper sulphate solution was more effective than ozonated water at preventing acute DD lesions. A random maximum likelihood model demonstrated that the odds ratio for DD in the ozonated water group was six times higher compared with DD in the acidified copper sulphate group. Most of the cows that were initially without any DD lesions (M0 + no other severe hoof lesion), remained lesion-free in both groups (copper sulphate group 97% and ozonated water group 88%). Despite trial design deficiencies, the findings indicate that acidified copper sulphate was a more effective solution in preventing DD than ozonated water.

A Comparative Study of Pain and Healing in Post-Dental Extraction Sockets Treated with Ozonated Water/Oil and Normal Saline

Aim

A comparative study of pain and healing in post-dental extraction sockets treated with ozonated water/oil and normal saline.

Purpose

The present study was conducted to evaluate the efficacy of ozonated water/oil in reducing pain and enhancing healing and swelling following dental extractions and surgical removal of impacted mandibular third molars.

Patients and Methods

Clinical trial was conducted involving 50 individuals requiring two-stage bilateral removal of tooth of which 25 patients were for asymptomatic bilateral extractions and 25 patients for surgical removal of asymptomatic bilaterally similar impacted mandibular third molars. The patients were divided into two groups following a split-mouth design: In group I, sterile ozonated water was irrigated in the sockets after extraction for 2 min on study side and normal saline on the control side following extraction. In group II, transalveolar extractions/surgical extraction of impacted mandibular III molars were carried out under copious irrigation with sterile ozonated water on study side and normal saline irrigation on control side evaluated by independent observer on 2nd, 4th and 7th day for the efficacy of ozonated water/oil in reducing pain and enhancing healing in post-dental extraction sockets.

Results

The use of ozonated water/oil increased the healing rate in all extraction cases, except in 4% of cases in which they did not show any effect of healing in extraction sockets on 7th postoperative day. The use of ozonated water/oil did not show any effects on the healing rate in impaction cases in all postoperative days. The use of ozonated water/oil showed decreased incidence of pain in subjects of both extraction and impaction cases.

Disinfection of caries-affected dentin using potassium titanyl phosphate laser, Rose bengal and Ozonated water on shear bond strength of deciduous teeth

AIM

To assess the efficacy of disinfection of caries-effected dentin (CAD) using KTP laser and different decontamination methods using ozonated water (OW), Rose Bengal photosensitizer (RBP), chlorhexidine (CHX), and Er, YAG laser on the shear bond strength (SBS) of adhesive resin bonded to deciduous teeth.

MATERIAL AND METHODS

A total of 50 extracted and radiographically verified carious primary molars were collected and scrutinized according to ICDAS criteria. Specimens were allocated randomly into five groups (n = 10) as per the type of CAD disinfectants. KTP laser, OW, RBP, CHX (control), and Er, YAG laser. After cavity sanitization, a resin adhesive (prime and bond NT) was smeared on the dentinal exterior followed by incremental composite filling. SBS evaluation was performed by employing specimens in the universal testing machine. The debonded surface was assessed under 40x magnification in a stereomicroscope to ascertain fracture mode. Statistical analysis was done by using the ANOVA and the Post Hoc Tukey multiple comparison tests (p < 0.05).

RESULTS

The highest SBS was exhibited by group 2 i.e., when OW was employed for CAD disinfection (10.25 ± 0.24 MPa). Whereas, the lowest SBS bond value was unveiled by samples in group 3 when RBP was applied for dentin surface sanitization (7.85 ± 0.59 MPa).CAD disinfection with KTP laser (8.25 ± 0.41 MPa), CHX (8.19 ± 0.73 MPa), and RBP displayed comparable bond values (p > 0.05).

CONCLUSION

Ozonated water and Er, YAG laser could be employed as cavity disinfectants in primary teeth as they demonstrated better shear bond strength without jeopardizing the adhesive binding capacity of restorative resins bonded to caries-affected dentin.

The physicochemical approaches of altering growth and biochemical properties of medicinal plants in saline soils

Medicinal plants are important sources of biochemical compounds affecting human health. However, because large areas of the world are subjected to different stresses including salinity, it is important to find methods, which may control the growth and biochemical properties of medicinal plants in such conditions. Another aspect of cropping medicinal plants in saline soils is the alteration of their biochemical properties by stress. Due to the significance of planting medicinal plants in saline soils, the objective of the present review article is to investigate and analyze the physicochemical approaches including soil leaching, organic fertilization, mineral nutrition, ozonated water, magnetism, superabsorbent polymers, and zeolite, which may control the effects of salinity stress on the growth and biochemical properties (production of secondary metabolites) of medicinal plants. In our just-published review article, we investigated the biological approaches, which may affect the growth and biochemical properties of medicinal properties in saline soils. Although salinity stress may induce the production of biochemical products in medicinal plants, the use of physicochemical approaches is also recommendable for the improved growth and biochemical properties of medicinal plants in saline soils. More has yet to be indicated on the use of the physicochemical approaches, which may affect the growth and biochemical properties of medicinal plants in salt stress conditions. KEY POINTS: • Growth and physiological alteration of medicinal plants in salt stress conditions. • The physicochemical approaches of such alteration have been reviewed. • More has yet to be indicated on the approaches, which may affect such properties.

Soil physicochemical (colloidal) properties affected by ozonated water and organic fertilization

More has to be investigated on the use of ozonated water (O3) for the improvement of growth medium properties. Accordingly, the objective was to examine the effects of O3 (control, 0.5, 1.0, and 2.0 mg L-¹) on soil physicochemical (colloidal) properties using organic fertilization (manure), under non-planted or planted conditions. Different soil physicochemical (colloidal) properties including soil available water (SAW), aggregate stability, soil porosity, pH, salinity (EC), organic carbon (SOC), CaCO₃, and cation exchange capacity (CEC) were determined. The experimental treatments and their interactions significantly (P ≤ 0.05) affected soil physicochemical properties including SAW (4.17-10.98%), aggregate stability and porosity (7.77-57.37%), SOC (0.15-2.09%), and CEC (17.68-42.75 Cmol( +)/kg). Interestingly, the single use of O3 or in combination with manure significantly decreased EC. Although O3 significantly decreased SOC in non-planted soils, it significantly increased SOC in planted soils. O3 may enhance soil physicochemical (colloidal) properties, and if combined with manure in a planted soil, such positive effects may be further enhanced.

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.

Application of ozonated water for treatment of gastro-thoracic fistula after comprehensive esophageal squamous cell carcinoma therapy: A case report

BACKGROUND

Gastro-thoracic fistula is a serious complication after radical surgery for esophageal cancer, and a conservative approach or endoscopic intervention is commonly applied to treat most cases.

CASE SUMMARY

Here we describe the case of a patient with a gastro-thoracic fistula which could not be closed during gastroscopy after receiving postoperative radiotherapy, together with severe multiple drug-resistant bacterial infection and chest wall fistula. The abscess was drained and local irrigation applied with ozonated water, together with oral ozonated water, which achieved a good effect and highlighted a new way to cure fistula in such patients.

CONCLUSION

Patients with gastro-thoracic fistula that cannot be closed and severe infection can be treated by drainage and flushing with ozonated water.

Ozone treatment pak choi for the removal of malathion and carbosulfan pesticide residues

Since the beginning of the widespread use of pesticides, their removal from food has become a serious concern. In this study, the removal of residual pesticides (malathion and carbosulfan) from pak choi via treatment with ozonated water was investigated. Under the optimal treatment conditions, i.e., 2.0 mg/L ozonated water and a treatment duration of 15 min, malathion and carbosulfan were degraded by 53.0 and 33.0%, respectively, without any significant changes in color. Even though there was a slight decrease in vitamin C content (~7.9 mg/100 g) following the treatments, a significant decrease in the microbial colonies on the vegetables was observed. Additionally, the pesticide degradation mechanism showed good fitting with a "first + first"-order kinetic model (R² > 0.9), and the slope (k) indicated that ozone had a more prominent degradation effect on malathion than on carbosulfan. Therefore, this study provides a theoretical basis for controlling agricultural pesticide residues in household applications.

Effect of Herbal Water, Ozonated Water, Water, and Chlorhexidine Mouthrinses on Oral Health Status of Children: A Randomized Controlled Trial

Aim

To evaluate the antibacterial effect of herbal water, ozonated water, and chlorhexidine mouthrinses on salivary Streptococcus mutans level and to assess their effectiveness of these mouthrinses on the oral health status of children.

Materials and methods

A parallel multiarm randomized controlled trial was conducted in 100 children aged 10–12 years. Debris index-simplified (DI-S), calculus index-simplified (CI-S), oral hygiene index-simplified (OHI-S) scores, and Streptococcus mutans counts were recorded at baseline (T₁). They were randomly divided into four equal groups (n = 25): HW, herbal water; OW, ozonated water; W, water; and CHX, chlorhexidine. Intervention period was 15 days and data collection was repeated after 15 days (T₂) and 30 days (T₃). Saliva samples were used to evaluate S. mutans count. Results were tabulated and analyzed statistically.

Results

OW had minimum DI-S score at T₂ and T₃ periods. HW had the minimum CI-S score at T₂ and T₃ periods. CHX had the minimum S. mutans count at T₂ and T₃ periods. OW showed maximum reduction in OHI-S score at T₂ period. HW showed maximum reduction in OHI-S score at T₃ period.

Conclusion

Herbal water and ozone water can be used as an alternative to chlorhexidine in maintaining the oral health status.

Clinical significance

Herbal water and ozonated water can be used in children instead of chemical mouthrinses to avoid any adverse effects.

How to cite this article

Mon J, Asokan S, Priya PRG, et al. Effect of Herbal Water, Ozonated Water, Water, and Chlorhexidine Mouthrinses on Oral Health Status of Children: A Randomized Controlled Trial. Int J Clin Pediatr Dent 2019;12(6):514–519.

Evaluation of ozone as an adjunct to scaling and root planing in the treatment of chronic periodontitis: A randomized clinico-microbial study

Background and Objectives

Mechanical plaque control is an essential part of periodontal therapy. In the present study, the efficacy of ozone water irrigation as an adjunct to scaling and root planing was evaluated in the treatment of generalized chronic periodontitis.

Materials and Methods

Twenty-four patients with chronic periodontitis selected for the study were randomly divided into Group A and Group B, receiving ozone water irrigation and distilled water irrigation, respectively, after scaling and root planing. Subgingival plaque was collected from the selected investigational teeth and was analyzed using BANA-Zyme™ Processor to evaluate the "red complex" periodontal pathogens. The clinical and microbiological parameters were recorded at baseline, 14 days, 21 days, and 2 months.

Results

The mean probing pocket depth scores for Group A and Group B at the baseline were 6.833 ± 1.193 and 7.833 ± 1.276; on day 14^th, they were 6.616 ± 1.403 and 7.083 ± 1.378; on day 21^st, they were 5.166 ± 0.937 and 6.083 ± 1.443;and on the 2^nd month, they were 4.500 ± 0.797 and 5.166 ± 1.029, respectively. At the 2^nd month, in Group A, 9 samples showed BANA negative and 3 samples showed BANA positive, and in Group B, 12 samples showed BANA negative and 0 sample showed BANA positive. The microbiological analysis showed a reduction in periodontal pathogens in both the groups.

Conclusion

Significant improvement in both clinical and microbiological parameters suggests that subgingival ozonated water irrigation could be an efficient adjunct to scaling and root planing in the treatment of chronic periodontitis.

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.

Spraying ozonated water on Bobal grapevines: Effect on grape quality

Ozone is a powerful oxidant that is increasingly used as sanitizing agent in the wine industry and even in the vineyard to control grapevine diseases. In this study, we evaluated the effect on grape enological quality of ozonated water spraying treatments carried out in Bobal grapevines during two consecutive harvest seasons. In the first season, ozonated water was applied once during the ripening period on grapevines trained on the traditional gobelet system (S₁). In the second season, ozonated water was applied three times between the fruit set and harvest on grapevines grown on a vertical trellis system (S₂). Grape quality on harvest day was evaluated through several enological and chromatic parameters, the phenolic maturity, the Varietal Aroma Potential Index (IPAv) and the phenolic and volatile composition. The S₁ treatment had a positive effect on the technological maturity, the chromatic parameters, the seed maturity and the content of glycosylated aroma precursors, phenolic compounds and free terpenoids of grapes. The S₂ treatment also improved the technological maturity and the content of total anthocyanins (pH 1.0) and free terpenoids, but had a negative impact on the chromatic parameters, the anthocyanin extractability and the content of glycosylated aroma precursors and phenolic compounds. Therefore, ozonated water sprayed on Bobal grapevines affected the quality of grapes, but the effect seemed to depend on the number of applications.

Application of an environmentally friendly preventive measure for the preservation of fresh vegetables

Vegetables are an important source of vitamins and minerals and are one of the most perishable products. Fresh vegetables need to be cleaned, sorted, washed and dried before entering distribution and trading systems. The quality of the product and the effect of the environment during preparation are very important. One method of stabilizing vegetable quality is the application of ozone, which is a strong disinfectant used to inactivate microorganisms. Ozone, when in contact with a product surface, does not leave any harmful by-products. This research aims to optimize carrot treatment with ozonated water and evaluate its effect and efficiency on the storage of products. A constant concentration of 1.53 ± 0.09 mg L^-1 ozone in water was used, and processing times of 5, 10, 15 and 20 min were applied. The carrots' weight and changes to the mould population on the carrots' surface during storage were observed after treatment with ozonated water. A decrease in mycological contamination on washable vegetable surfaces occurred within the first 5 min, and longer processing times (more than 5 min) did not influence the efficacy of the treatment. Thus, using ozonated water at an ozone concentration of 1.53 ± 0.09 mg L^-1 reduced the mould population by up to 99.99% and could also prolong carrot storage duration up to 1.7 times. Treatment of carrots with ozonated water had minimal impact on the carrots' weight.

Inactivation of Escherichia coli O157:H7 by ozone in different substrates

Ozone has a broad antimicrobial spectrum and each microorganism species has inherent sensitivity to the gas. The objective of this study was to evaluate the effect of ozone gas on Escherichia coli O157:H7 inoculated on an organic substrate, and the efficacy of ozonated water in controlling the pathogen. For the first experiment, E. coli O157:H7 (ATCC® 43890™) was inoculated in milk with different compositions and in water, which was ozonated at concentrations of 35 and 45 mg L^-1 for 0, 5, 15, and 25 min. In the second experiment, water was ozonated at 45 mg L^-1 for 15 min. E. coli O157:H7 was exposed for 5 min to the ozonated water immediately after ozonation, and after storage for 0.5, 1.0, 1.5, 3.0, and 24 h at 8 °C. The results showed that the composition of the organic substrate interfered with the action of ozone on E. coli O157:H7. In lactose-free homogenized skim milk, reductions of 1.5 log cycles were obtained for ozonation periods of 25 min at the concentrations tested. Ozonated water was effective in inactivating of E. coli O157:H7 in all treatments. The efficiency of ozone on E. coli O157:H7 is influenced by the composition of the organic substrates, reinforcing the need for adequate removal of organic matter before sanitization. Furthermore, refrigerated ozonated water stored for up to 24 h is effective in the control of E. coli O157:H7.

Kinetics of antifungal activity of home-generated ozonated water on Candida albicans

Background and Purpose:

Candida-associated denture stomatitis is one of the most common forms of oral candidiasis among denture wearers. Regarding this, the aim of the present study was to evaluate the antifungal effects of home-generated ozonated water on the adhesion of the C. albicans attached to the surface of the denture base acrylic resins.

Materials and Methods:

For the purpose of the study, different concentrations of C. albicans were added to the tubes containing acrylic resin blocks, and then incubated for 2 h at 35°C. The samples were assigned into three groups, each of which contained 42 samples, including normal saline (NS) solution as the negative control, nystatin (N) solution as the positive control, and ozonated water as the test group. The samples were washed and placed in an ultrasonic bath. Subsequently, the saline solution was cultured on Sabouraud dextrose agar. The concentrations of Candida were evaluated during the contact times.

Results:

The test group (i.e., ozonated water) with 114 colony-forming units (CFU) showed a significant reduction of Candida colonies, compared to the NS group with 2,172 CFU. The 120- and 1-minute incubation with ozonated water showed the highest and lowest effects on the viability of Candida adhered to the acrylic resin, respectively.

Conclusion:

Based on the findings, home-generated ozonated water can be applied to remove the Candida attached to the surface of the denture plates.

Effect of ozonated water on the surface roughness of dental stone casts

Infection control of dental stone cast is an important issue. Ozone is effective for disinfection against microorganisms and inactivation of viruses. However, there is little information regarding the use of ozone. We prepared 4 types of gypsum specimens and 3 types of disinfectants (4-5 ppm Ozonated water [OZW], 2% glutaraldehyde [GL], and 1% sodium hypochlorite [SH]). Gypsum specimens were immersed in each disinfectant for 5 and 10 min, and surface roughness was then examined using laser scanning microscopy. Surface microstructure was investigated using scanning electron microscopy. Immersion of gypsum specimens in SH, GL, and OZW increased the surface roughness to a maximum of 1.04, 0.37, and 0.30 μm, respectively, based on the difference between the average values of surface roughness before and after the disinfection procedure. The effects of OZW and GL were comparable. OZW is useful as a candidate for relatively safe disinfection of material for dental stone casts.

Evaluation of ozonated water using ASTM E1174 for standardized testing of handwash formulations for healthcare personnel

Removal of bacteria by handwashing with ozonated water was evaluated using the ASTM E1174 standard test method. Thirty healthy volunteers were assigned randomly to three groups: ozonated water, antimicrobial soap and water, and non-antimicrobial soap and water. A 3 log₁₀ cfu reduction was achieved by washing hands with ozonated water or antimicrobial soap and water. However, ozonated water was not significantly superior to non-antimicrobial soap and water. Ozonated water may remove bacteria from the hands to at least a similar extent as that by non-antimicrobial soap and water in the absence of visible dirt or body fluid contamination.

Unusual Root Canal Irrigation Solutions

Microorganisms and their by-products play a critical role in pulp and periradicular pathosis. Therefore, one of the main purposes of root canal treatment is disinfection of the entire system of the canal. This aim may be obtained using mechanical preparation, chemical irrigation, and temporary medication of the canal. For this purpose, various irrigation solutions have been advocated. Common root canal irrigants, such as sodium hypochlorite, chlorhexidine, and a mixture of tetracycline, acid, and detergent have been extensively reviewed. The aim of this review was to address the less common newer root canal irrigation solutions, such as citric acid, maleic acid, electrochemically activated water, green tea, ozonated water, and SmearClear.

Qualitative analyses of the antimicrobial effect of ozonated water on supragingival plaque and salivary microbes

BACKGROUND

Ozone is an unstable gas, capable of oxidizing any biological entity. It is an effective bactericide in its gaseous as well as aqueous form.

AIMS

The objective of this study was to determine the in-situ antimicrobial effect of 0.1 ppm ozonated water on plaque and salivary microorganisms.

SUBJECTS AND METHODS

24 h old supragingival plaque (SP) was collected from the two most posterior teeth in the contralateral quadrants before and after a 30 s rinse with either distilled water (control group) or 0.1 ppm ozonated water (test group). Simultaneously stimulated whole saliva (SWS) was collected for both groups. The SP and SWS were stained with LIVE/DEAD Baclight Bacteria Viability fluorescent kit to visualize live and dead microbes. The salivary flow rate, calcium and protein level were also determined in the pre- and post-rinsed samples. The data obtained was subjected to One Way ANOVA test using Minitab 14 statistical software (PA, USA).

RESULTS

0.1 ppm ozonated water was found effective in reducing the bacterial load in both the 24 h plaque and SWS samples, but it did not eliminate them completely. In addition, there was no statistically significant effect of the ozonated water rinse on the salivary flow rate, salivary calcium and protein concentration.

CONCLUSIONS

0.1 ppm ozonated water rinse can be an effective adjunct to tooth brushing and flossing to maintain plaque and salivary bacterial load.