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

Ozone therapy in dentistry: An overview of the biological mechanisms involved (Review)

At low medically-relevant concentrations, ozone serves as an oxidant with a wide spectrum of antimicrobial activity and the ability to promote healing and reduce inflammation. Despite providing therapeutic benefits in a range of diseases, certain adverse effects and contraindications of ozone treatment must be considered. These are primarily related to toxicity from inhalation and systemic types of administration and can be avoided by following relevant guidelines and recommendations. Ozone therapy has been implemented in a number of fields of dentistry and the most commonly used formulations for the oral cavity are gaseous ozone, ozonized water and ozonized oil. The biological mechanisms underlying the molecular effects of ozone have been increasingly reported, but currently remain largely unknown. The aim of the present review was to provide an overview of the mechanisms involved in ozone interaction with dental tissues. The present review focused on relevant evidence regarding the effect of ozone on dental tissues, including periodontal structures, dental cells, enamel and dentine, considering in vitro studies in addition to animal and human studies. A variety of biological mechanisms acting through multiple biochemical target pathways were reported to be responsible for the therapeutic effects of ozone. The main beneficial effects of ozone occurred in the following domains: antimicrobial activity, remineralization and microstructural changes of hard dental tissues, immunomodulation and biostimulation of dental and periodontal cells. Additional research could provide further insights into the use of ozone, increase its use for broader clinical applications and assist in the selection of targeted protocols.

Irrigants and irrigation activation systems in Endodontics

Root canal infections are typically polymicrobial and involve strong bacterial interactions. The goal of endodontic treatment is to remove infected content from the root canal system to allow the healing of a pre-existing periapical lesion or to prevent infection of the periradicular tissues. Instrumentation alone is not capable of touching all of the root canal walls. Therefore, the irrigation process is an essential step in the endodontic treatment. However, due to the complex anatomy of the root canal system, this cleaning is very challenging. Although syringe and needle irrigation associated with the use of chemical substances is still the most used method, it does not guarantee optimal cleaning of the root canals. As a result, not only alternative irrigating substances but also numerous activation systems - which are technologies that aim to optimize the action of irrigating substances, both chemically and physically - have been developed. This work aimed to review the characteristics of both classic and current alternatives of irrigating substances and irrigation activation systems.

Prevention of Dry Socket with Ozone Oil-Based Gel after Inferior Third Molar Extraction: A Double-Blind Split-Mouth Randomized Placebo-Controlled Clinical Trial

Tooth extraction is followed by a sequence of elaborate local changes affecting hard and soft tissues. Dry socket (DS) can occur as intense pain around and in the extraction site, with an incidence from 1–4% after generic tooth extraction to 45% for mandibular third molars. Ozone therapy has gained attention in the medical field because of its success in the treatment of various diseases, its biocompatible properties and its fewer side effects or discomfort than drugs. To investigate the preventive effect of the sunflower oil-based ozone gel Ozosan® (Sanipan srl, Clivio (VA), Italy) on DS, a double-blind split-mouth randomized placebo-controlled clinical trial was conducted according to the CONSORT guidelines. Ozosan® or the placebo gel were put in the socket, and the gels were washed off 2 min later. In total, 200 patients were included in our study. The patient population comprised 87 Caucasian males and 113 Caucasian females. The mean age of the included patients was 33.1 ± 12.4 years. Ozosan reduced the incidence of DS after inferior third molar extraction from 21.5% of the control to 2% (p < 0.001). Concerning the dry socket epidemiology, the incidence was not significantly correlated with gender, smoking or mesioangular, vertical or distoangular Winter’s classification. Post hoc power calculation showed a power of 99.8% for this data, with alpha = 0.001.

Antimicrobial and cleaning effects of ultrasonic-mediated plasma-loaded microbubbles on Enterococcus faecalis biofilm: an in vitro study

BACKGROUND

Enterococcus faecalis (E. faecalis) is the most frequently isolated bacteria from teeth with root canal treatment failure. This study aims to evaluate the disinfection effect of ultrasonic-mediated cold plasma-loaded microbubbles (PMBs) on 7d E. faecalis biofilm, the mechanical safety and the mechanisms.

METHODS

The PMBs were fabricated by a modified emulsification process and the key reactive species, nitric oxide (NO) and hydrogen peroxide (H₂O₂) were evaluated. The 7d E. faecalis biofilm on human tooth disk was constructed and divided into the following groups: PBS, 2.5%NaOCl, 2%CHX, and different concentrations of PMBs (10⁸ mL^-1, 10⁷ mL^-1). The disinfection effects and elimination effects were verified with confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Microhardness and roughness change of dentin after PMBs treatment were verified respectively.

RESULTS

The concentration of NO and H₂O₂ in PMBs increased by 39.99% and 50.97% after ultrasound treatment (p < 0.05) respectively. The CLSM and SEM results indicate that PMBs with ultrasound treatment could remove the bacteria and biofilm components effectively, especially those living in dentin tubules. The 2.5% NaOCl presented an excellent effect against biofilm on dishes, but the elimination effect on dentin tubules is limited. The 2% CHX group exhibits significant disinfection effect. The biosafety tests indicated that there is no significant changes on microhardness and roughness after PMBs with ultrasound treatment (p > 0.05).

CONCLUSION

PMBs combined with ultrasound treatment exhibited significant disinfection effect and biofilm removal effect, the mechanical safety is acceptable.

Adjunctive therapies for in vitro carious lesions: Antimicrobial activity, activation of dentin metalloproteinases and effects on dental pulp cells

BACKGROUND

Adjunctive therapies used before dental restorative procedures may encourage carious tissue removal. Beyond promising antimicrobial properties, treatments could positively modulate the dentin-pulp complex while not interfering with restoration survival. Herein, we evaluated a set of substances and their effects on carious lesions and the underlying dentin or pulp cells.

METHODS

Artificial caries lesions were developed in bovine teeth cavities immersed in Streptococcus mutans and Lactobacillus casei co-cultures. The cavities were treated according to the following groups: Phosphate Buffer Saline (PBS), Chlorhexidine (CHX), Papacárie® (Papain gel), Ozone (O₃), and antimicrobial Photodynamic Therapy (aPDT). After treatments, samples were cultivated to count isolated microbial colonies. The zymography assay evaluated the activity of dentin metalloproteinases (MMP-2 and MMP-9). Cell viability was indirectly assessed on human dental pulp cells after 24, 72, or 120 h, whereas the odontodifferentiation potential was evaluated after ten days of cell culture.

RESULTS

CHX and aPDT led to around 1 log bacterial load reduction. PBS, CHX, and aPDT showed the eventual expression of MMP-2 and MMP-9. Cell viability was reduced (< 30%) after 120 h for all groups compared to the control. CHX, O3, and aPDT induced greater odontodifferentiation (≈ 20% higher) than PBS and papain gel.

CONCLUSION

Adjunctive therapies presented little or no biological significance in reducing bacterial load in artificial carious lesions. Although the activation of endogenous metalloproteinases may represent a possible concern for adhesive restorations, some of these treatments may have a positive role in dental pulp tissue repair.

Effects of an Ozonated Water Irrigator on the Plaque Index and Bleeding Index of Pregnant Women

Pregnancy causes physiological changes in the woman’s body, which can also affect oral health. Therefore, pregnant women may manifest gingival inflammation that is favored by their hormonal increase. This clinical trial (ClinicalTrials.gov Identifier: NCT04140643) evaluated the variation in the plaque index (PI) or bleeding index (BOP) in pregnant women after daily use of an ozonated water irrigator and proper home oral hygiene, compared to a control group who only performed home oral hygiene. The inclusion criteria were the gestation period from the 14th week to the 30th week, a diagnosis of gingivitis, and a minimum number of teeth equal to 20. The PI and BOP index were evaluated at T0, fifteen days after T0 (T1), and two months after T1 (T2). The PI values systematically decreased over time (F (1.19) = 41.82) in both groups, with a systematic difference in PI values between the two groups (F (1.19) = 6.28, p = 0.021). A statistically significant difference was assessed in the BOP index at T2 between the two groups, with the control group suffering a higher BOP index. The results show that the patients in the study group showed a decrease in the BOP index over the three time points, in contrast to the control group, due to the beneficial properties of ozonated water.

Ozone Gel in Chronic Periodontal Disease: A Randomized Clinical Trial on the Anti-Inflammatory Effects of Ozone Application

Simple Summary

The search for new topical antimicrobial treatments represents an actual challenge both in orthopedics and in dentistry. As regards the latter, antiseptics represent an aid to the non-surgical treatment commonly employed to contrast periodontitis. This study aims to assess the efficacy of an ozone-based gel with respect to the more common chlorhexidine gels. Ten participants were treated by means of nonsurgical periodontal therapy, with, in addition, a chlorhexidine gel and an ozone one, both, respectively, used in half of the oral sites. Patients were visited at baseline, after one month, and after three months, and at each time point clinical indexes were assessed. This study revealed that the use of the ozonized gel in addition to the standard non-surgical therapy generally did not significantly differ if compared to the use of chlorhexidine. Based on this, ozone deserves consideration for its wide applicability in several clinical fields, especially considering the reduced number of shortcomings with respect to those generally related to chlorhexidine.

Abstract

The search for new topical treatments able to display not only antimicrobial properties but also a multiplicity of other beneficial effects while expressing safe cytocompatibility toward host tissues is being progressively developed. Antiseptics represent an aid to the gold standard nonsurgical treatment Scaling-and-Root-Planing (SRP) for periodontal disease. This split-mouth study aims to assess the efficacy of the ozonized gel GeliO₃ (Bioemmei Srl, Vicenza, Italy) plus SRP (experimental treatment), with respect to SRP + chlorhexidine gel. Ten participants were treated with SRP + chlorhexidine gel (control sites) and with SRP + ozone gel (trial sites). After 1 (T₁) and 3 months (T₂) from baseline (T₀), patients were revisited. At each time-point, the following indexes were assessed: probing pocket depth (PPD), clinical attachment level (CAL), gingival index (GI), plaque index (PI), and bleeding on probing (BoP). It has been assessed that the use of the ozonized gel in addition to SRP did not show significant differences if compared to conventional SRP + chlorhexidine. Chlorhexidine was found to be more effective than ozone in reducing CAL and GI at T₂. Ozone deserves consideration for its wide applicability in several clinical fields. In this connection, we also glance at the latest research on ozone therapy.