A Prospective Cohort Study Assessing the Impact of Fixed Orthodontic Appliances on Saliva Properties and Oral Microbial Flora.

PURPOSE: Orthodontic treatment may introduce a risk to the integrity of enamel due to plaque accumulation and colonisation by oral microbes. This prospective cohort study observed the effect of fixed, self-ligating orthodontic appliances on saliva properties and oral microbial flora. Materials and Methods: Thirty adolescent patients were recruited (13 female, 17 male, mean age 13.97 ±â€¯2.07 years). Saliva samples were collected before placement of fixed orthodontic appliances (T0), and 4 (T1) and 12 (T2) weeks later. Salivary pH, flow rate and buffering capacity were recorded. All saliva samples were cultured on agar plates for 2 days. Salivary prevalence of Neisseria spp., streptococci, Staphylococcus aureus, coagulase-negative staphylococci and Candida albicans were assessed. Results: High buffering capacity was reported in 21 patients at T0, 22 patients at T1 and in 28 patients at T2. Saliva flow rate also increased over time (7.08 ml/5 min at T0, 7.93 ml/5 min at T1 and 8.35 ml/5min at T2). Mean pH was 7.63 at T0, 7.67 at T1 and 7.78 at T2. There was no evidence that either pH or the number of colonies of any of the microbial species changed over time. Conclusion: The increased buffering capacity of saliva as well as the salivary flow rate after initial bonding might be protective against the development of dental caries. Current microbial findings indicate that initiation of orthodontic treatment may not be associated with significant changes in oral microbial flora.

Point-prevalence survey of healthcare facility-onset healthcare-associated Clostridium difficile infection in Greek hospitals outside the intensive care unit: The C. DEFINE study.

BACKGROUND: The correlation of Clostridium difficile infection (CDI) with in-hospital morbidity is important in hospital settings where broad-spectrum antimicrobial agents are routinely used, such as in Greece. The C. DEFINE study aimed to assess point-prevalence of CDI in Greece during two study periods in 2013. METHODS: There were two study periods consisting of a single day in March and another in October 2013. Stool samples from all patients hospitalized outside the ICU aged ≥18 years old with diarrhea on each day in 21 and 25 hospitals, respectively, were tested for CDI. Samples were tested for the presence of glutamate dehydrogenase antigen (GDH) and toxins A/B of C. difficile; samples positive for GDH and negative for toxins were further tested by culture and PCR for the presence of toxin genes. An analysis was performed to identify potential risk factors for CDI among patients with diarrhea. RESULTS: 5,536 and 6,523 patients were screened during the first and second study periods, respectively. The respective point-prevalence of CDI in all patients was 5.6 and 3.9 per 10,000 patient bed-days whereas the proportion of CDI among patients with diarrhea was 17% and 14.3%. Logistic regression analysis revealed that solid tumor malignancy [odds ratio (OR) 2.69, 95% confidence interval (CI): 1.18-6.15, p = 0.019] and antimicrobial administration (OR 3.61, 95% CI: 1.03-12.76, p = 0.045) were independent risk factors for CDI development. Charlson's Comorbidity Index (CCI) >6 was also found as a risk factor of marginal statistical significance (OR 2.24, 95% CI: 0.98-5.10). Median time to CDI from hospital admission was shorter with the presence of solid tumor malignancy (3 vs 5 days; p = 0.002) and of CCI >6 (4 vs 6 days, p = 0.009). CONCLUSIONS: The point-prevalence of CDI in Greek hospitals was consistent among cases of diarrhea over a 6-month period. Major risk factors were antimicrobial use, solid tumor malignancy and a CCI score >6.

Investigation of bacteremia induced by removal of orthodontic mini-implants.

The aim of this study was to investigate potential occurrence of bacteremia in orthodontic patients after removal of miniscrews.The study group comprised 30 healthy subjects (17 males, 13 females) with a mean age of 24.1 years treated with self-ligating fixed appliances and mini-implant anchorage. Two 20 ml venous blood samples were obtained prior to and 30-60 seconds after miniscrew explantation following an aseptic technique. Blood culturing in aerobic and anaerobic conditions was carried out by means of the BACTEC blood culture analyzer. Microbiological analysis showed that none of the pre- and post-operative samples exhibited detectable bacteremia. Future research should be focused on determining the collective bacteremic effect of a sequence of orthodontic procedures including miniscrew placement or removal, typically performed during a single treatment session.