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.

Effect of minimally invasive restorations on microorganism count in the oral cavity of a patient with early childhood caries.

BACKGROUND: The effect of minimally invasive restorations on the microorganism count in the oral cavity of children with early childhood caries (ECC) has been only briefly discussed in the literature. CASE REPORT: This study presents the case of a child with ECC who was treated using a minimally invasive restorative approach and the patient's salivary levels of Streptococcus mutans, Lactobacillus spp. and Candida spp. were recorded throughout the treatment. In addition, a detailed discussion on the role of these microorganisms in the development of ECC is also presented. TREATMENT: Included minimally invasive techniques such as ART and removal of caries with ultrasound. The whole unstimulated saliva samples of the patient were inoculated in culture media for microbial count. FOLLOW-UP: A 6-monthly review was achieved for a period of 1 year. The microbiological data were statistically analysed and a significant reduction (ANOVA, p < 0.05) of all microorganisms studied were recorded at the end of the treatment. CONCLUSION: The therapy used in this case and the salivary microorganism levels reported at the end of the treatment showed that minimally invasive restorative techniques were effective in controlling oral microorganisms involved in ECC.

Cross-sectional microhardness of bovine enamel subjected to three paediatric liquid oral medicines: an in vitro study.

AIM: This study aimed to investigate the in vitro effects of three paediatric liquid oral medicines on bovine dental enamel subsurfaces under pH cycling conditions. METHODS: Bovine enamel blocks were evaluated for surface hardness at baseline for sample selection. 52 intact bovine enamel blocks (16mm(2)) were randomly divided into four groups (n=13) according to the immersion treatments: G1: antibiotic (Klaricid®), G2: antihistamine (Claritin®), G3: antihistamine (Dimetapp®) and G4: control (de-ionised water). The blocks were submitted to pH cycling treatments twice a day for 12 days. The medicines were evaluated for pH, viscosity, and concentration of calcium, phosphate and fluoride. After the treatment period, cross-sectional microhardness (CSMH) measurements of the enamel blocks were taken and the data, expressed in Knoop hardness number (kg/mm(2)) was used to calculate the ΔS. STATISTICS: ANOVA followed by the Tukey test were used for statistical analyses (p<0.05). RESULTS: The antibiotic Klaricid® showed the highest concentration of fluoride, calcium and phosphate. Considering pH and viscosity, the following pattern was observed according to the treatment group: G4>G1>G2>G3 and G1>G2>G3>G4 respectively. Regarding the demineralisation pattern, the following results were observed: G4>G3>G2>G1. Compared to the control, the antibiotic and both the antihistamines provoked less demineralisation of the enamel blocks (p<0.05). CONCLUSIONS: Antibiotic G1 (Klaricid®) presented an in vitro protective effect against acid attacks probably due to its mineral content and viscosity.