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.

Bovine teeth can reliably substitute human dentine in an intra-tooth push-out bond strength model?

AIM: To investigate the reliability of using bovine teeth as an alternative to human teeth in an intra-tooth push-out model by comparing the bond strength of three root canal sealers in both tooth substrates. METHODOLOGY: From human and bovine incisors (12 per group), one 1-mm disc was obtained from each root. On each disc, three standard 0.8-mm-diameter holes were drilled through the dentine. After irrigation, the holes were filled with one of three root canal sealers: AH Plus, MTA Fillapex or Total Fill BC Sealer. Tooth slices were kept in contact with sterile gauze moistened in PBS solution (pH = 7.2) for 7 days at 37 °C, and finally, a push-out load was applied until sealer dislocation. The bonded interface area was calculated to obtain data in MPa. The push-out data for each sealer and the overall push-out data for human and bovine teeth were compared (Mann-Whitney U). Kruskal-Wallis was used to study the sealers behaviour at each of the dental substrates. Multiple comparisons were performed using Mann-Whitney U after Bonferroni correction (P < 0.05). RESULTS: Dentine substrate did not influence the push-out of either individual sealers or overall sealers tested (Mann-Whitney U, P > 0.05). In both human and bovine samples, AH Plus performed better than BC Sealer and MTA Fillapex, whilst BC Sealer also provided a superior push-out compared to MTA Fillapex (Mann-Whitney U, P < 0.05). CONCLUSION: When using an intra-tooth model, bovine teeth did not significantly influence the bond strength of sealers.

Do smear-layer removal agents affect the push-out bond strength of calcium silicate-based endodontic sealers?

AIM: To evaluate the effect of 17% ethylenediaminetetraacetic acid (EDTA), 2.25% peracetic acid (PA) or 10% citric acid (CA) on the push-out bond strength of calcium silicate-based endodontic sealers [MTA Fillapex (Angelus, Londrina, Brazil) and Total Fill BC Sealer (FKG, La Chaux-de-Fonds, Switzerland)] to root dentine after different periods of immersion in phosphate-buffered saline (PBS). AH Plus (Dentsply DeTrey, Konstaz, Germany) was used as a reference material for comparison. METHODOLOGY: Thirty human maxillary incisors were selected and three 1-mm discs were obtained from the middle third of each root. On the axial surface of each disc, three 0.8-mm-diameter holes were drilled through the dentine. After standardized irrigation, each dentine disc from the same root was treated for smear-layer removal with one of the three tested chelating solutions: EDTA, PA or CA. After that, the holes were dried with paper points and filled with one of the three test root canal sealers. The filled dental slices were further immersed in PBS solution (pH 7.2) for 7 days (T1) or 30 days (T2) at 37 °C, before the push-out assay. Friedman, Kruskal-Wallis and Mann-Whitney tests were used respectively to estimate the impact of the independent variables (solutions, sealers and period of PBS immersion) on the push-out bond strength. The level for significance was set at α = 5% and data were further subjected to a Bonferroni correction. RESULTS: Solutions and periods of immersion did not significantly influence the displacement resistance (P = 0.285, and P = 0.104, respectively) of sealers to root dentine. On the other hand, the type of sealer significantly affected the push-out bond strength (P = 0.000). AH Plus was associated with greater resistance to dislodgment compared with Total Fill BC Sealer and MTA Fillapex (P = 0.000). MTA Fillapex resulted in the lowest push-out bond strength (P = 0.000). CONCLUSION: The use of different chelating agents did not influence the push-out bond strength of endodontic sealers. Calcium silicate-based sealers had lower push-out bond strength values compared with a conventional epoxy resin-based sealer (AH Plus).

Delimitation of homogeneous regions in the UNIFESP/EPM healthcare center coverage area based on sociodemographic indicators.

CONTEXT: The drawing up of adequate Public Health action planning to address the true needs of the population would increase the chances of effectiveness and decrease unnecessary expenses. OBJECTIVE: To identify homogeneous regions in the UNIFESP/EPM healthcare center (HCC) coverage area based on sociodemographic indicators and to relate them to causes of deaths in 1995. DESIGN: Secondary data analysis. SETTING: HCC coverage area; primary care. SAMPLE: Sociodemographic indicators were obtained from special tabulations of the Demographic Census of 1991. MAIN MEASURES: Proportion of children and elderly in the population; family providers' education level (maximum: > 15 years, minimum: < 1 year) and income level (maximum: > 20 minimum wages, minimum: < 1 minimum wage); proportional mortality distribution RESULTS: The maximum income permitted the construction of four homogeneous regions, according to income ranking. Although the proportion of children and of elderly did not vary significantly among the regions, minimum income and education showed a statistically significant (p < 0.05) difference between the first region (least affluent) and the others. A clear trend of increasing maximum education was observed across the regions. Mortality also differed in the first region, with deaths generated by possibly preventable infections. CONCLUSION: The inequalities observed may contribute to primary health prevention.

[Epidemiology of nosocomial infections in a second level hospital]. / Epidemiología de las infecciones nosocomiales en un hospital de segundo nivel.

OBJECTIVE: To determine the incidence, specific rates, areas of greatest risk and causal agents of nosocomial infections at the Hospital General de Durango, of the Secretaría de Salud, Mexico. MATERIAL AND METHODS: Prospective study of nosocomial infection vigilance during one year including all patients discharged during this period. RESULTS: An overall rate of 9 infections per 100 discharged patients was found, the higher specific rates were in the areas of intensive pediatric care and births and the lowest were in the surgery, pediatric and gynecology and obstetrics departments. Infections were most frequent in urinary tract and surgical wounds as well as pneumonia among adults; among children, the most frequent were bacteremias and an epidemic outbreak with predominating Serratia marscecens was observed. Most patients presented one only infectious process and E coli, Klebsiello and Enterobacter sp. were the most frequently isolated microorganisms. CONCLUSIONS: The nosocomial infection rate observed in this study is higher than the average in Mexico for similar institutions. The most affected areas were those of critical patients and new births with urinary tract and surgical wound infections, and pneumonia, and the most frequent causal agents were enteric Gram-negative bacilli. These findings suggest guide lines for the design of a nosocomial infection control program, adjusted to the particular features of each institution.

The effect of a new oral hygiene training program on approximal caries in 12-15-year-old Brazilian children: results after three years.

This study evaluated the effects of a new oral hygiene training program on approximal caries in a population of 12-13-year-old Brazilian schoolchildren with a well-established habit of daily toothbrushing with a F dentifrice. Two hundred twenty-two children were randomly allocated into two test groups (I and II) and one control group (III). Group I subjects were trained to establish needs-related oral hygiene habits based on self-diagnosis and a new behavioral principle, the 'linking method', for establishment of habits. The first three visits (20 minutes each) were scheduled at two-day intervals. They were recalled for a monthly check-up during the first 4 months, and then every 3 months for reevaluation of the results based on self-diagnosis. Group II subjects were recalled at the same intervals for detailed oral hygiene instruction on how to clean every tooth surface using dental tape, toothbrush, and fluoride dentifrice. Group I developed significantly fewer (p < 0.001) new approximal manifest (dentin) caries lesions than groups II and III. The mean values (SEM) were 2.3 (0.29), 4.7 (0.59), and 5.3 (0.68), respectively. The conclusions from our study are: In a toothbrushing population using fluoride dentifrices and fluoridated drinking water, the oral hygiene training program with behavioral modification significantly reduced caries incidence on approximal surfaces. Frequent repetition of training in meticulous oral hygiene is almost redundant.

[Antisperm antibodies in prepubertal patients]. / Anticuerpos antiesperma en pacientes en edad prepuberal.

Antisperm antibodies were studied in 44 patients with less than 14 years of age, with unilateral testicle torsion and other testicular pathologies with vascular and inflammatory processes. The clinical and evolution of testicular size after one year of initial evaluation were obtained. Four cases had positive antisperm antibodies: One testicular torsion, two acute orchitis and one varicocele. In all the cases including those with positive antibodies the testicular size was normal in both sides. These findings agree with the theory of initiation of autoimmune process after a unilateral testicular damage, although we can not give data to support any damage to the contralateral testes.

[Nutritional status of Indian children of Alto Xingu and evaluation of the use of arm perimeter in the diagnosis of protein-calorie malnutrition]. / Estado nutricional de crianças índias do Alto Xingu e avaliação do uso do perímetro braquial no diagnóstico da desnutrição protéico-calórica.

STUDY OBJECTIVE: The purpose of this study was to determine the presence of malnutrition in indian children of Alto Xingu region in Brazil, and to evaluate the usefulness of arm circumference and QUAC index in the diagnosis of protein-energy malnutrition (PEM). SITE: The indian population of Alto Xingu maintains most of its traditional customs. PATIENTS: 335 children were studied prospectively in at least one of seven consecutive years between 1974 and 1980, and 1278 measurements were obtained of weight, height, and arm circumference. MEASUREMENTS AND RESULTS: The annual prevalence of PEM (weight-for-height) less than 90% according to Brazilian reference tables was 4.1% in children aged under 1 year, 7.3% in children from 1 to 5 years of age, and 7.5% in children older than 5. According NCHS tables, however, values of 1.0%, 2.8%, and 1.1% were obtained for the respective age groups. The sensitivity and specificity of arm circumference and QUAC index were calculated in relation to the weight-for-height relation. According to Brazilian reference tables, arm circumference had a sensitivity of 8.9% and specificity of 99.3%, whereas the QUAC index had a sensitivity of 11.1% and specificity of 98.3%. However, according to NCHS tables, slightly different values were obtained. The sensitivity and specificity in this case were 23.5% and 99.3%, respectively, for arm circumference and 35.3% and 98.3%, respectively, for the QUAC index. CONCLUSIONS: The authors concluded that the prevalence of PEM was low in the Alto Xingu and that arm circumference and the QUAC index should only be used in situations suited to their sensitivity and specificity.

[Microbiological study of dental clinic air at the University Hospital of the University of Sao Paulo Dental School]. / Estudo da microbiota do ar da clínica odontológica do Hospital Universitário da Faculdade de Odontologia da Universidade de São Paulo.

The purpose of this study was to analyse the environmental microbiote and to verify its occurrence in different areas. During 3 months, from April to June 1986, several air samples of working areas of the Dental Clinic of Faculdade de Odontologia da Universidade de São Paulo were analised. The study consisted of 10 exposures in strategically selected points during 10 minutes each, blood-agar plates and Sabouraud-agar plates. It was done the identification in genera and in some cases at species, according to the conventional methods. The plates were incubated, and the colonies isolated and identified. It was done the statistical analysis (Z test) and it was observed bigger incidence of bacteria than fungi and more diversity of the fungi than bacteria. From the Odontological health point of view, the isolated microorganisms (ubiquitous in the air) do not reveal patogenicity however the determinants of the local hygiene.

Salivary Streptococcus mutans and caries prevalence in Brazilian schoolchildren.

The aim of the present study was to determine the levels of salivary Streptococcus mutans in Brazilian schoolchildren, and its possible correlation with caries prevalence. A positive correlation between different levels of S. mutans and caries prevalence was observed, individuals with high levels of S. mutans (greater than 100 colonies) had a DMFS significantly higher than those with low or no detectable S. mutans (0, 1-20, 21-40 colonies).