Effect of nano-hydroxyapatite with biomimetic analogues on the characteristics of partially demineralised dentin: An in-vitro study.

BACKGROUND: Research on dentin remineralisation protocols in particular 'biomimetic remineralisation' has gained huge momentum. Aim of this study was to evaluate if biomimetic analogs, incorporated in n-HAp, as an experimental formulation could aid in remineralization of artificial caries-like dentin and have anti-microbial effect on cariogenic bacteria, S mutans. MATERIALS AND METHODOLOGY: An experimental paste was formulated using nano-hydroxyapatite (nHAp) with Non-Collagenous Protein analogs- polyacrylic acid (PAA), sodium tri-poly phosphate (STPP) with Simulated Body Fluid. Partially demineralised dentin specimens were divided into three groups (n=10) based on the remineralisation treatment as, Group A- n-HAp paste, Group B- n-HAp and NCP analogues and Group C (Control) - no treatment. At the end of the experimental period, the specimens were assessed using SEM-EDS analysis and Vickers microhardness testing. Further, the antimicrobial efficacy of the paste was assessed. STATISTICAL ANALYSIS: The results were statistically analyzed using ANOVA with post-hoc Bonferroni test. RESULTS: Dentin specimens treated with the experimental paste revealed greater tubular occlusion, with intra tubular deposits and increased mineral content. Specimens treated with n-HAp alone had higher microhardness values and inhibitory effect on the cariogenic bacteria. CONCLUSION: Non-Collagenous Protein analogs incorporated in n-HAp could remineralize the demineralised dentin and had antibacterial efficacy against S mutans.

Study of antibacterial and antifungal efficacy of platelet-rich fibrin and platelet-rich fibrin matrix.

BACKGROUND: Platelet concentrates are extensively utilized in the medical and dental field to promote tissue regeneration. The profusion of endogenous growth factors in platelets α-granules transmit their use for enhanced wound healing. However, little attention has been given to study their antimicrobial potential. This study was conducted to assess the antibacterial and antifungal property of platelet-rich fibrin (PRF) and PRF matrix (PRFM). MATERIALS AND METHODOLOGY: Blood samples were obtained from 16 participants, PRF and PRFM were processed as per the protocol prescribed by Choukroun et al. and Lucarelli et al., respectively. The susceptibility test against microbiota in the root canal and Candida albicans was assessed through minimum inhibition zone by agar diffusion technique. RESULTS: PRF showed an effective antibacterial property, however, did not perform well against C. albicans strains. PRFM did not show any antibacterial or antifungal properties. CONCLUSIONS: The antibacterial efficacy of PRF may prove beneficial when used in the revascularization procedure of immature necrotic teeth.

Predictors of death in infants with probable serious bacterial infection.

BackgroundBacterial infections account for a significant proportion of neonatal and infant mortality globally. We aimed to identify predictors of death in infants with probable serious bacterial infection (PSBI) defined as signs/symptoms of possible serious bacterial infection along with baseline C-reactive protein (CRP) ≥12 mg/l.MethodsWe did a secondary analysis using the data collected from 700 infants with PSBI who participated in a randomized controlled trial in India in which zinc or placebo was given in addition to the standard antibiotics. Logistic regression was used to estimate the associations between relevant variables and death within 21 days.ResultsThose infants who were fed cow's milk or formula before the illness episode had 3.7-fold (95% confidence interval (CI) 1.5-9.3) and 5.3-fold (95% CI 2.0-13.6) higher odds of death, respectively. Lethargy (odds ratio (OR) 2.4, 95% CI 1.1-5.4) and CRP (OR 1.9, 95% CI 1.1-3.3) were also independent predictors of death. In the model including only clinical features, female gender (OR 2.25, 95% CI 1.0-5.0), abdominal distention (3.7, 95% CI 1.1-12.3), and bulging fontanelle (5.8, 95% CI 1.1-30.5) were also independent predictors for death.ConclusionFormula or cow milk feeding prior to the illness, lethargy at the time of presentation, and high serum CRP levels predicted death in infants with PSBI.

Predictors of time to recovery in infants with probable serious bacterial infection.

INTRODUCTION: Serious bacterial infections continue to be an important cause of death and illness among infants in developing countries. Time to recovery could be considered a surrogate marker of severity of the infection. We therefore aimed to identify clinical and laboratory predictors of time to recovery in infants with probable serious bacterial infection (PSBI). METHODS: We used the dataset of 700 infants (7-120 days) enrolled in a randomised controlled trial in India in which 10mg of oral zinc or placebo was given to infants with PSBI. PSBI was defined as signs/symptoms of possible serious bacterial infection along with baseline C-reactive protein(CRP) level >12mg/L. Time to recovery was defined as time from enrolment to the end of a 2-day period with no symptoms/signs of PSBI and daily weight gain of at least 10g over 2 succesive days on exclusive oral feeding. Cox proportional hazard regression was used to measure the associations between relevant variables and time to recovery. RESULTS: Infants who were formula fed prior to illness episode had 33% longer time to recovery (HR-0.67, 95%CI-0.52, 0.87) than those who were not. Being underweight (HR-0.84, 95%CI-0.70, 0.99), lethargic (HR-0.77, 95%CI-0.62, 0.96) and irritable (HR-0.81, 95%CI-0.66, 0.99) were independent predictors of time to recovery. Baseline CRP was significantly associated with time to recovery (P<0.001), higher CRP was associated with longer time to recovery and this association was nearly linear. CONCLUSION: Simple clinical and laboratory parameters such as formula feeding prior to the illness, being underweight, lethargic, irritable and having elevated CRP levels could be used for early identification of infants with PSBI at risk for protracted illness and could guide prompt referral to higher centers in resource limited settings. This also provides prognostic information to clinicians and family as longer recovery time has economic and social implications on the family in our setting. TRIAL REGISTRATION: ClinicalTrials.gov NCT00347386.

Zinc as adjunct treatment in infants aged between 7 and 120 days with probable serious bacterial infection: a randomised, double-blind, placebo-controlled trial.

BACKGROUND: Serious bacterial infections are a major cause of death in early infancy in developing countries. Inexpensive and accessible interventions that can add to the effect of standard antibiotic treatment could reduce infant mortality. We measured the effect of zinc as an adjunct to antibiotics in infants with probable serious bacterial infection. METHODS: In this randomised, double-blind, placebo-controlled trial, we enrolled infants aged 7-120 days with probable serious bacterial infection at three hospitals in New Delhi, India, between July 6, 2005, and Dec 3, 2008. With computer-generated sequences, we randomly assigned infants in permuted blocks of six, stratified by whether patients were underweight or had diarrhoea at enrolment, to receive either 10 mg of zinc or placebo orally every day in addition to standard antibiotic treatment. The primary outcome was treatment failure, which was defined as a need to change antibiotics within 7 days of randomisation, or a need for intensive care, or death at any time within 21 days. Participants and investigators were masked to treatment allocation. All analyses were done by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT00347386. FINDINGS: 352 infants were randomly assigned to receive zinc and 348 to placebo. 332 given zinc and 323 given placebo could be assessed for treatment failure. Significantly fewer treatment failures occurred in the zinc group (34 [10%]) than in the placebo group (55 [17%]; relative risk reduction 40%, 95% CI 10-60, p=0·0113; absolute risk reduction 6·8%, 1·5-12·0, p=0·0111). Treatment of 15 (95% CI eight to 67) infants with zinc would prevent one treatment failure. Ten infants receiving zinc died compared with 17 given placebo (relative risk 0·57, 0·27-1·23, p=0·15). INTERPRETATION: Zinc could be given as adjunct treatment to reduce the risk of treatment failure in infants aged 7-120 days with probable serious bacterial infection. FUNDING: Department of Biotechnology, Government of India; the European Commission; the Meltzer Foundation; and the Research Council of Norway.