The Use of Ozone in Dentistry and Medicine

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.

Effectiveness of Topical Ozone Gel Application in the Management of Postextraction Wound Healing: An In Vivo Study

AIM

The purpose of the current study was to determine the effectiveness of topical ozone gel application in the management of postextraction wound healing.

MATERIALS AND METHODS

The current study involved a total of 40 participants. The patients were randomly placed into two groups with sample size estimated as n = 20 in each group. Group A: Control: patients received only saline irrigation and group B: patients receiving topical ozone gel. The surgical procedure was standardized for all groups, and local anesthesia was used during the procedure. After the removal of the mandibular third molar, the control group irrigated the socket with saline, whereas in the study group, the socket was filled with ozone gel. On the first, third, fifth, and seventh postoperative days, a single examiner evaluated each participant for postoperative mouth opening, discomfort, and patient satisfaction. The t-test was used to analyze quantitative data, whereas the Fisher exact test was employed to analyze qualitative data. Statistical significance was defined as a p value less than 0.05.

RESULTS

On comparison of patient satisfaction, in the ozone gel group, 13 patients were very satisfied but in the control group, 8 patients were very satisfied. On comparison of pain intensity, on the 5th day, the complete absence of pain patients was more in the ozone gel group (12 patients) compared with the control group (4 patients). There was a statistically significant difference found between these two groups (p < 0.001). On comparison of mouth opening, on the 3rd and 5th day, mouth opening was better in the ozone gel group (29.22 ± 1.28 and 34.06 ± 0.09) compared with the control group (27.38 ± 1.03 and 31.14 ± 0.82), respectively. And there was a statistically significant difference found between these two groups (p < 0.001) on both the days.

CONCLUSION

The current study came to the conclusion that using ozone gel significantly improves postoperative pain, mouth opening range, and promotes faster wound healing.

CLINICAL SIGNIFICANCE

The primary goals of postoperative care for exodontia patients have always been pain management and infection control. The most frequent postoperative consequences are pain and edema. Hence, ozone therapy can be used as an effective topical agent to manage postextraction pain and swelling in healthy patients without the need for excess medications. How to cite this article: Varghese LJ, Lahiri B, Penumatsa NV, et al. Effectiveness of Topical Ozone Gel Application in the Management of Postextraction Wound Healing: An In Vivo Study. J Contemp Dent Pract 2023;24(11):887-890.

Ozone Therapy in Medicine and Dentistry: A Review of the Literature

Ozone has been successfully used in medicine for over 100 years due to its microbiological qualities. Its powerful oxidation impact, which results in the production of free radicals, and its ability to cause the direct death of nearly all microorganisms is the basis for its bactericide, virucide, and fungicide properties. Ozone also has a medicinal impact that speeds up blood flow and aids wound healing. Ozone may be applied as a gas or dissolved in water for medical purposes. Despite the benefits of using ozone therapeutically, concerns about its use in dentistry still exist. We aimed to provide a summary of the current uses of ozone in medicine and dentistry. An electronic search was performed for all English scientific papers published between 2012 and 2023 using PubMed, Cochrane, and Google Scholar search engines. Ozone, clinical applications, medicine, and dentistry were the search terms used. Seventy full-text articles describing the use of ozone therapy in medicine and dentistry were included in the present review. Ozone has shown several beneficial effects in the medical field. However, despite the encouraging in vitro evidence, the clinical use of ozone in dentistry has not yet been demonstrated as highly effective.

A minireview of recent developments in ozone detection using optical chemodosimeters

The development of optical chemodosimeters for ozone detection has been an important research subject in recent years because of the environmental and biological relevance of ozone. The design and development of ozone chemodosimeters, as well as their numerous applications from 2009 to 2022, have all been thoroughly covered in this minireview. In this review, chemodosimeters are categorised according to their distinctive reaction mechanism with ozone. The comparative data for each of these chemodosimeters have also been provided here. We have also discussed the difficulties and potential prospects of this fast-evolving discipline. To the best of our knowledge, this is the first review that has comprehensively analysed the progress made in the development of ozone chemodosimeters.

Potential Clinical Applications of Ozone Therapy in Dental Specialties-A Literature Review, Supported by Own Observations

Apart from conventional treatment, dentists are increasingly relying on physical therapy modalities in their clinical practice. The aim of this literature review is to analyze the clinical relevance and potential uses of ozone in modern dentistry. The research question is geared towards detailing the multiple potential applications of ozone therapy in a range of dental specialties. Based on the available literature, accessed via the PubMed, Google Scholar, Scopus, and EBSCO databases, a detailed search of the electronic literature was performed for 2001-2022. Eligible studies were chosen according to inclusion and exclusion criteria, using keywords: ozone, ozone therapy, therapeutic applications, oxidants, dental disinfectants, oral medicine, physical therapy in dentistry. Out of 834 manuscripts, 273 studies were curated. A total of 70 publications were used in the final consideration. After assessing their quality, they were analyzed to determine the relevance and potential use of ozone in the various aspects of modern dentistry. Ozone therapy is used mainly as an adjunct to the primary clinical or pharmacological treatment. In some cases of oral mucosal disease, it has proven effective as a primary therapy. During the literature analysis, it was noted that ozone therapy in dentistry is a subject of ongoing research, and the results are not always consistent. The multitude of studies in the literature on the applications of ozone in dentistry reflects the search for its undiscovered physical therapeutic potential.

Spectroscopy of Laser-Induced Dielectric Breakdown Plasma in Mixtures of Air with Inert Gases Ar, He, Kr, and Xe

The generation of ozone and nitrogen oxides by laser-induced dielectric breakdown (LIDB) in mixtures of air with noble gases Ar, He, Kr, and Xe is investigated using OES and IR spectroscopy, mass spectrometry, and absorption spectrophotometry. It is shown that the formation of NO and NO₂ noticeably depends on the type of inert gas; the more complex electronic configuration and the lower ionization potential of the inert gas led to increased production of NO and NO₂. The formation of ozone occurs mainly due to the photolytic reaction outside the gas discharge zone. Equilibrium thermodynamic analysis showed that the formation of NO in mixtures of air with inert gases does not depend on the choice of an inert gas, while the equilibrium concentration of the NO+ ion decreases with increasing complexity of the electronic configuration of an inert gas.

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.

A highly sensitive fluorescent probe for ozone based on coumarin-benzothiazole derivative

Ozone is widely used in daily life, but studies have shown that O3 can damage human trachea and lungs, leading to diseases such as asthma, emphysema, and bronchitis. Therefore, it is of great significance to develop a simple and efficient detection method for monitoring O3 in living cells. In this study, 3-(but-3-en-1-yl)-2-(7-(but-3-en-1-yloxy)-2-oxo-2H-chromen-3-yl)benzo[d]thiazol-3-ium (BCT) as a new type of water-soluble fluorescent probe was synthesized by substitution reaction of 4-bromo-1-butene and hydroxycoumarin-benzothiazole derivatives, which can specifically detect ozone in aqueous solution. The interaction of ozone on the probe can be completed within 20 min, the fluorescence intensity is significantly enhanced, and it has the advantages of high sensitivity (detection limit LOD = 43 nM). The influence of pH on the fluorescent performance of BCT shows that the probe with super stability under weak alkali and acidic environment, which provides the necessary conditions for its detection of ozone in physiological system detection. Therefore, BCT is expected to become an effective tool for detecting ozone in cellular organisms.

Influence of Laser and Ozone Pretreatment on the Shear Bond Strength of Fissure Sealants: An In Vitro Comparative Study

Aim:

To evaluate the shear bond strength (SBS) of 3 fissure sealants used alone and with ozone and laser pretreatment.

Materials and Methods:

For the SBS test, the flattened enamel surfaces of 90 healthy third molars were randomly divided into nine groups ( n  =  10 for each groups), based on different sealants (BeautiSealant, Fuji Triage, and Grandio Seal) and pretreatment conditions (no pretreatment, pretreatment with ozone, and pretreatment with neodymium-doped yttrium aluminum garnet [Nd:YAG laser]). Ozone was applied for 30 s in caries superficial mode, and Nd:YAG laser was applied for 60 s. After the pretreatment procedures, sealants were placed inside a mold on the enamel surface. SBS was measured with a universal testing machine. Data were analyzed using analysis of variance. Tukey’s multiple comparison tests were applied to determine the difference between the groups (α  = 0.05).

Results:

The lowest SBS was observed in the Fuji triage group. Nd:YAG laser and ozone did not affect the SBS of BeautiSealant. However, significant differences were determined in the Fuji triage and Grandio Seal groups after pretreatment procedures ( P  < .05).

Conclusion:

Ozone and laser can be employed to disinfect fissures before BeautiSealant application.

Ozone therapy in veterinary medicine: A review

Ozone (O₃) is a triatomic form of oxygen. As O₃ rapidly dissociates into water and releases a reactive form of oxygen that may oxidize cells, the gas mixture of O₃/O₂ is used in medicine. ATP is widely available for cellular activity. O₃ can be administered via the systemic and local routes. Although O₃ is known as one of the most powerful oxidants, it also promotes antioxidant enzymes. Additionally, it stimulates some of the cells of the immune system and inactivates pathogens, including bacteria, fungi, yeasts, protozoa, and viruses. Owing to these activities, O₃ is used to improve several diseases, both in human and in veterinary medicine. Considering the wide scope of O₃ application, the aim of this review was to reiterate the mechanisms of action of O₃ and its utilization in different mammalian species (bovine, ovine-caprine, equine, canine, porcine).

Randomized controlled clinical trial on bleaching sensitivity and whitening efficacy of hydrogen peroxide versus combinations of hydrogen peroxide and ozone

The clinical efficacy regarding bleaching sensitivity and tooth shade lightening using a standard hydrogen peroxide (H₂O₂) bleaching gel was compared with the additional use of ozone either before or after application of H₂O₂. Using computer-generated tables, 45 participants were randomly allocated into three groups (n = 15 each) in this investigator-driven, single-centre trial. In Group 1, upper anterior teeth were bleached using ozone (produced via a healOzone X4 device) for 60 seconds, then 38% H₂O₂ for 20 minutes; in Group 2, 38% H₂O₂ application (20 min) was followed by ozone (60 s); air produced by the healOzone machine (60 s) followed by 38% H₂O₂ (20 min) was used in Group 3 (control). Bleaching sensitivity was evaluated via visual analogue scales, and a treatment-blinded reader objectively recorded tooth shades using a colorimeter before and 24 hours after bleaching (at α = 0.05). The H₂O₂/ozone combination did not result in pain sensations, while both ozone/H₂O₂ and H₂O₂ alone increased bleaching sensitivity (p < 0.001). Teeth achieved lighter shades (higher L*/lower b* values) after bleaching in all groups (p < 0.001), while Ozone boosted lighter tooth shades, irrespective of its use before or after H₂O₂ (p < 0.05). Due to the complimentary effects, applying ozone after H₂O₂ seems preferable for bleaching.

Ozone Treatment on Dentin Hypersensitivity Surfaces - A Pilot Study

BACKGROUND

Dentin hypersensitivity (DH) is a frequent condition in adults and difficult to treat. The aim of this single-blind, randomised controlled clinical trial was to investigate immediate and long-term effect of ozone treatment (Prozone, W&H NORDIC AB) for 12 seconds on hypersensitive teeth compared to placebo treatment, using a split-mouth design.

METHODS

26 patients (12 M, 14 F, mean age 44+ 2) were included in the study having at least two teeth with confirmed DH in different quadrants of the dentition (each subject had one test and one control tooth). A visual analogue scale (VAS) was used to measure the patients´ pain perception immediately and at a long-term follow-up three months later.

RESULTS

Significant reduction in pain perception from DH surfaces was demonstrated from ozone treated test teeth as well as in placebo treated control teeth. We found a moderate (16.2%) but significant pain relief (p< 0.012) over time in 57.7% of all treated teeth.

CONCLUSION

Results from this study confirm previously published results showing no significant effect of ozone treatment on hypersensitive teeth compared to placebo treatment.

[Assessment of antibacterial efficacy of ozone therapy in treatment of caries at the white spot stage]

Effect on cariogenic flora is the key toremineralizing therapy efficacy in treatment of initial caries (at the white spot stage). Ozone in dentistry is used as a highly effective antibacterial agent. Treatment of white spot lesions with the ozone-air mixture leads to significant increase of efficacy in non-invasive treatment of initial caries.

OBJECTIVE

clinical and microbiological assessment of antibacterial efficacy of ozone therapy in treatment of caries at the white spot stage.

MATERIAL AND METHODS

The trial recruited 86 patients for non-invasive treatment of caries at the white spot stage which included the complex of professional oral hygiene, medicamental treatment of white spot lesions with hydrogen peroxide 3% and chlorhexidinedigluconate 0,2%, treatment with the ozone-air mixture and application of hydroxyapatite Са2+. Material for microbiological study was received before the treatment, after the complex of professional oral hygiene and medicamental treatment of white spot lesions conducted as well as after the treatment with the ozone-air mixture.

RESULTS

Before the treatment up to 16 kinds of microorganisms on the surface of white spot lesion were detected with the following shares: S. mutans (19.9%), S. salivarius (15.1%), S. epidermidis (8.7%), S. mitis (6.5%), Lactobacillus (6.5%) and different kinds of staphylococci (10.8%). After the complex of professional oral hygiene and medicamental treatment conducted decrease in number of cariogenic microorganisms was indicated as follows: S. mutans - from 1·105 to 1·104, S. salivarius - from 1·107 to 1·106, S. epidermidis - from 1·105 to 1·104, S. mitis - from 1·104 to 1·103, Lactobacillus - from 1·104 tо 1·103. After the treatment of tooth enamel with the ozone-air mixture increase in microorganisms was not observed. The efficacy of ozone on cariogenic microorganisms exceeds significantly the efficacy of 3% hydrogen peroxide and 0,2% chlorhexidinedigluconate.

CONCLUSION

It is strongly advisable to include ozone in protocol of non-invasive treatment of initial dental caries.

Histomorphometric and microtomographic evaluation of the effects of hyperbaric oxygen and systemic ozone, used alone and in combination, on calvarial defect healing in rats

PURPOSE

The aim of this study was to compare the efficacy of hyperbaric oxygen and systemic ozone, used separately and in combination, on the healing of bone defects.

MATERIAL AND METHODS

Sixty male Wistar rats were divided into 4 groups (n = 15) according to treatment (control, hyperbaric oxygen [HBO], ozone [O], and HBO plus O [HBO-O]) and divided further into 3 subgroups according to day of sacrifice (postsurgical days 5, 15, and 30). Surgery was performed under general anesthesia to create a critical-size bone defect (5 mm in diameter) in the cranium. After sacrifice, microtomographic images of all samples were recorded, and histomorphometric analysis was performed.

RESULTS

Histologic and radiologic measurements showed that the values of all experimental groups were higher than those of the control group. Histologic scores for all experimental groups were statistically higher than those for the control group day 30 (O, P = .045; HBO, P = .049; HBO-O, P = .042). Histologic scores also were statistically higher for the HBO group on day 5 (P = .045) and day 15 (P = .009) compared with the control group. Microtomographic scores were higher for the experimental groups than for the control group, with statistically significant differences for group O on day 5 (P = .033) and day 30 (P = .0045) and for group HBO on day 15 (P = .005). Histologic and radiologic analyses showed positive correlations.

CONCLUSION

Within the limitations of this study, the use of hyperbaric oxygen and ozone, separately and in combination, were shown to be effective in increasing bone healing. Combined usage was no more effective in stimulating bone healing than separate usage.

Application of ozone in the treatment of periodontal disease

Gingivitis and periodontitis are most common inflammatory diseases of supporting tissues of teeth. Role of microbial etiology and host response in progression of gingival and periodontal diseases has been well established. Because of the beneficial biological effects of ozone, due to its antimicrobial and immunostimulating effect, it is well indicated in the treatment of gingival and periodontal diseases. The objective of this article is to provide a general review about clinical applications of ozone in treatment of periodontal diseases and to summarize the available in vitro and in vivo studies in Periodontics in which ozone has been used.

Effect of ozone gas on the shear bond strength to enamel

Ozone is an important disinfecting agent, however its influence on enamel adhesion has not yet been clarified.

Antimicrobial effects of ozonated water on the sanitization of dental instruments contaminated with E. coli, S. aureus, C. albicans, or the spores of B. atrophaeus

OBJECTIVES

Ozone has been used as an alternative method for the decontamination of water, food, equipment and instruments. The objective of this study was to evaluate the antimicrobial effects of ozonated water on the sanitization of dental instruments that were contaminated by Escherichia coli, Staphylococcus aureus, Candida albicans and the spores of Bacillus atrophaeus.

METHODS

A total of one hundred and twenty standardized samples of diamond dental burs were experimentally contaminated with E. coli (ATCC 25922), S. aureus (ATCC 6538) and C. albicans (ATCC 18804) and the spores of B. atrophaeus (ATCC 6633) for 30 min. After the contamination, the samples were exposed to ozonated water (10mg/L O(3)) for 10 or 30min. The control group was composed of samples that were exposed to distilled water for 30 min. After the exposure to the ozonated water, 0.1 mL aliquots were seeded onto BHI agar to count the colony-forming units per milliliter (CFU/mL) of E. coli, S. aureus, and B. atrophaeus. Sabouraud dextrose agar was used to count the CFU/mL of C. albicans. The results were subjected to an analysis of variance and the Tukey test.

RESULTS

For all of the microorganisms studied, the ozonated water reduced the number of CFU/mL after 10 and 30 min of sanitization, and this microbial reduction was dependent on the duration of the exposure to the ozonated water. E. coli exhibited the greatest reduction in CFU/mL (2.72-3.78 log) followed by S. aureus (2.14-3.19 log), C. albicans (1.44-2.14 log) and the spores of B. atrophaeus (1.01-1.98 log).

CONCLUSION

The ozonated water was effective in reducing the CFU of E. coli, S. aureus, C. albicans and B. atrophaeus spores, suggesting that ozonated water can be used for the sanitization of dental instruments.

Newer root canal irrigants in horizon: a review

Sodium hypochloride is the most commonly used endodontic irrigant, despite limitations. None of the presently available root canal irrigants satisfy the requirements of ideal root canal irrigant. Newer root canal irrigants are studied for potential replacement of sodium hypochloride. This article reviews the potential irrigants with their advantages and limitations with their future in endodontic irrigation.

The antibacterial effect of gas ozone after 2 months of in vitro evaluation

The aim of this study was to evaluate the effect of HealOzone on two microorganisms, 4 and 8 weeks after treatment, using a tooth cavity model. Four groups of caries-free third molars (n = 12) were used (A, B, C and D). Three cavities were prepared into each tooth. After sterilization, groups A and B were inoculated with Streptococcus mutans, and groups C and D, with Lactobacillus casei for 48 h. One cavity of each tooth was used to evaluate the infection. After inoculation, groups B and D were treated with ozone (60 s), and groups A and C were used as controls. Then, the two cavities of each tooth were filled with composite, and the teeth were stored in sucrose medium. The restorations were removed after 4 and 8 weeks, respectively; dentin chips were collected, and the amount of microorganisms was determined. Ozone treatment reduced significantly the amount of S. mutans compared to the control group (p ≤ 0.05). This antibacterial effect was able to be seen after 4 (p = 0.0005) and 8 (p = 0.0002) weeks. No significant difference was found between the control and treated group as far as L. casei is concerned (p > 0.05). HealOzone (60 s) can provide some antibacterial treatment against S. mutans even after 8 weeks. However, an elimination of the microorganisms through HealOzone seems not to be possible. L. casei was more resistant to ozone. Although ozone exerts a significant antibacterial effect against S. mutans, it is probably not enough as the only antibacterial method, during the fillings therapy.

Effects of ozone and ND:YAG laser pretreatment on bond strength of self-etch adhesives to coronal and root dentin

OBJECTIVES

The aim of this study was to evaluate the effects of two different disinfection treatments--ozone and Nd:YAG laser application--on shear-bond strength (SBS) of self-etch adhesives to coronal and root dentin.

MATERIALS AND METHODS

Sixty extracted human canines were ground flat, exposing the coronal and root dentin surfaces, and randomly divided into three groups. The surfaces were untreated (Control) or treated with ozone (HealOzone, KaVo) or Nd:YAG laser (Fidelis III, Fotona). Coronal and root dentins of 10 teeth of each group were treated with a two-step self-etch adhesive (Clearfil SE Bond, Kuraray Medical; SE), whereas the remaining 10 teeth were treated with a one-step self-etch adhesive (Clearfil Tri-S Bond, Kuraray Medical; S3). A resin composite (Clearfil Majesty Esthetics, Kuraray Medical) was then placed, and SBS was tested with a universal testing machine. Failure modes were determined under a stereomicroscope. The mean SBS values of each group were calculated, and data were subjected to statistical analysis (p = 0.05).

RESULTS

For the coronal dentin, Control/SE showed significantly higher values than Control/S3, Ozone/S3, and Nd:YAG/S3. Although Ozone/SE showed significantly higher values than Nd:YAG/S3 (p < 0.05), the differences within the other groups were not significant for the root dentin (p > 0.05). Comparison of two dentin substrates in each group did not show any significant difference except for Control/SE, in which coronal dentin showed higher SBS. The failure modes of all groups were mainly adhesive.

CONCLUSION

Pretreatments with Ozone or Nd:YAG laser did not impair the SBS of both of the self-etch adhesives used to coronal and root dentin.

Antimicrobial efficacy of ozonated water, gaseous ozone, sodium hypochlorite and chlorhexidine in infected human root canals

AIM

To determine the antimicrobial efficacy of ozonated water, gaseous ozone, sodium hypochlorite and chlorhexidine in human root canals infected by Enterococcus faecalis.

METHODOLOGY

Thirty human maxillary anterior teeth were prepared and inoculated with E. faecalis for 60 days. Eppendorf tubes were connected to the coronal portion of the teeth. Urethane hoses were attached to the tubes and to the entrance of a peristaltic pump. The exit of the apparatus corresponded to the apical portion of the root canals. The test irrigating solutions were ozonated water, gaseous ozone, 2.5% sodium hypochlorite (NaOCl), 2% chlorhexidine that circulated at a constant flow of 50 mL min(-1) for 20 min. Samples from the root canals were collected and immersed in 7 mL Letheen Broth (LB), followed by incubation at 37 degrees C for 48 h. Bacterial growth was analysed by turbidity of the culture medium and subculture on a specific nutrient broth. A 0.1 mL inoculum obtained from LB was transferred to 7 mL of brain heart infusion and incubated at 37 degrees C for 48 h. Bacterial growth was checked by turbidity of the culture medium carried out in triplicate.

RESULTS

No solution used as an irrigant over a 20-min contact time demonstrated an antimicrobial effect against E. faecalis.

CONCLUSION

The irrigation of infected human root canals with ozonated water, 2.5% NaOCl, 2% chlorhexidine and the application of gaseous ozone for 20 min was not sufficient to inactivate E. faecalis.

The evidence supporting alternative management strategies for early occlusal caries and suspected occlusal dentinal caries

OBJECTIVE

To assess the strength of the evidence describing the effectiveness of alternative strategies to the detection and management of early occlusal caries and suspected occlusal dentinal caries.

METHODS

Nine detection and intervention decision points were identified as being central to the management of early occlusal caries and suspected occlusal dentinal caries, or suspicious areas. For each decision point, the evidence for effectiveness was assessed, using existing systematic reviews when available, and nonsystematic review methods when necessary.

RESULTS

For the 2 detection decisions (early occlusal caries and suspicious areas) the strength of the evidence was weak. Accuracy in detecting early occlusal caries was extremely variable within and across detection methods. Approximately 50% of suspicious areas identified had dentinal caries. The strength of the evidence for effectiveness of nonsurgical approaches for the management of early occlusal caries was weak for all 3 management strategies examined (doing nothing, sealants, remineralization). This evidence suggested that sealants were highly effective, with remineralization reflecting moderate effectiveness. For the management of suspicious areas, the strength of the evidence was still weaker and reflected the same relative effectiveness. For the surgical management strategy for suspicious areas, operative treatment, the evidence was strong and reflected high effectiveness for preventive resin restorations, but no evidence was available for minimally invasive techniques.

CONCLUSION

Identification methods for early occlusal caries are not accurate. The strength of the evidence for effectiveness of nonsurgical management strategies for early occlusal caries is at best, weak. The available evidence suggests that sealing both enamel caries and suspected occlusal dentinal caries is the most effective management approach if subsequent maintenance of the sealed surfaces can be assured.

Assessment of the safety of two ozone delivery devices

OBJECTIVES

To evaluate the safety of an ozone gas device designed for use in dentistry.

METHODS

Two commercially available ozone applicators, Ozi-cure and HealOzone were used in a clinical simulation using a phantom head while recordings of ozone levels were made in pharyngeal and nasal regions of the patient and near the mouth of the operator. Clinical simulations included ozone application for caries management and endodontic treatment. Recordings were made five times with different levels of suction to assess the effect on ozone levels.

RESULTS

The results with Ozi-cure on caries mode resulted in a peak ozone level in the pharynx of 1.33+/-0.52 ppm when no suction was used. The use of suction nearby reduced the ozone level to zero while suction on the opposite side of the mouth reduced the level to 0.22+/-0.04 ppm. Used on endodontic mode the peak ozone level in the pharynx was 5.51+/-1.63 ppm when no suction was used. The use of suction nearby reduced the ozone level to zero while suction on the opposite side of the mouth reduced the level to 0.84+/-0.54 ppm. Recordings in the patient's nasal region gave a peak of 0.22 ppm when using the Ozi-cure on endodontic mode with no suction. At the operator's mouth the ozone level did not exceed 0.01 ppm although the characteristic smell of ozone was detectable. All recordings with HealOzone were zero. Concentrations of 15 ppm were recorded in a simulated tooth cavity with Ozi-cure and >20 ppm with HealOzone.

CONCLUSIONS

The Ozi-cure device when used without adequate suction allows ozone to be reach a concentration above permitted levels and therefore should not be used. The HealOzone was safe to use.

Antimicrobial potential of ozone in an ultrasonic cleaning system against Staphylococcus aureus

The aim of this study was to evaluate the antimicrobial potential of ozone applied to 3 different solutions in an ultrasonic cleaning system against Staphylococcus aureus. A total of 120 mL of S. aureus were mixed in 6 L of the experimental solutions (sterilie distilled water, vinegar and sterile distilled water + Endozime AWpluz) used in a ultrasonic cleaning system (UCS). Ozone was produced by an electric discharge through a current of oxygen and bubbling with flow rate at 7g/h ozone (1.2%) into the microbial suspensions. Ten mL of each experimental suspension were collected and 5 fold dilutions were made in 9 mL of BHI and incubated at 37°C for 48 h. Bacterial growth was evaluated by turbidity of the culture medium. At the same time, 1 mL of bacterial samples was collected and inoculated in BHIA plates. After incubation at 37°C for 48 h, the number of colony forming units (cfu) per mL on BHIA surface was counted. In dilution test in BHI tubes and in BHIA plates (cfu/mL), bacterial growth was not observed in any of the experimental solutions when ozone was added. Under the tested conditions, it may be concluded that the addition of ozone to a ultrasonic cleaning system containing different experimental solutions resulted in antibacterial activity against S. aureus.

The Use of Ozone in Dentistry and Medicine

A previous paper, recently published in Primary Dental Care, gave an overview of the medical uses of ozone and outlined some of its uses in dentistry. The current paper focuses on a description of use of ozone in the management of root caries and considers recent studies in this area. There has been relatively limited research into the non-invasive (pharmaceutical) management of root caries. The best management strategy still remains to be developed. Initial studies have indicated that an application of ozone for a period of either 10 or 20 seconds is capable of clinically reversing leathery root carious lesions. It is suggested that, subject to confirmation from extensive trials, this simple and non-invasive technique may benefit many patients with root caries throughout the world since this approach to treat root caries can easily be employed in primary care clinics and in the domiciliary treatment of home-bound elderly people and immobile patients in hospices and hospitals.