Dosimetry of pulsed magnetic field towards attaining bacteriostatic effect on Enterococcus faecalis: Implications for endodontic therapy.

AIM: To examine in a laboratory setting the efficacy of moderate to high strength magnetic fields, as a potential bacteriostatic stimulus, against Enterococcus faecalis, one of the causative agents for infection during root canal treatments. METHODOLOGY: Four different strengths (1, 2, 3 and 4 T) of the pulsed magnetic field (PMF) were applied in thirty repetitions to bacterial suspension. A pickup coil setup was used to measure the electromotive force induced inside the bacterial suspensions. The optical density (OD) was monitored over time (for 16 h 40 min) during the post-treatment period to assess bacterial growth. Along with the change in OD values, live/dead assay, membrane depolarization study, atomic force microscopy (AFM), scanning electron microscopy (SEM) and reactive oxygen species (ROS) assay on selected samples were studied to evaluate the effect of PMFs. All results were analysed using one-way ANOVA followed by post hoc Tukey test and considered significant at p < .05. Regression analysis (at a confidence of 95%, α = 0.05) was performed on the bacterial growth and membrane depolarization studies to determine progressive changes of the outcomes. RESULTS: The peak value of the induced electromotive force was recorded as 0.25 V, for the 4 T magnetic field pulse with a pulse width of 16 ms. There was a significant arrest of bacterial cell growth after an exposure to PMFs of 1 T, 3 T and 4 T (ANOVA score: F (4, 495) =395.180 at p = .05). The image-based qualitative results of the live/dead assay using fluorescence microscopy techniques indicated that an exposure to higher PMFs (3 T/ 4 T) induced a bacteriostatic effect in a longer post-exposure timescale. Evidence of altered membrane potential within the 2 h of exposure to 4 T PMF was supported by the incidence of elevated ROS. For the ROS assay, a significant difference occurred for 4 T exposed samples (ANOVA score: calculated F (1, 3) =20.2749 at p = .05). SEM and AFM observations corroborated with the outcomes, by portraying significant membrane damage. CONCLUSION: In a laboratory setting, PMFs with higher magnitudes (3 T and 4 T) were capable of inducing bacteriostatic effects on E. faecalis.

The efficacy of transdermal and oral diclofenac for post-endodontic pain control: A randomised controlled trial.

OBJECTIVE: The aim of the present study was to compare the effect of transdermal diclofenac patch against oral diclofenac for post-endodontic pain control. MATERIALS AND METHODS: Thirty-two patients with symptomatic irreversible pulpitis in single-rooted premolar teeth of either arch were treated endodontically in a single visit by a single endodontist. Oral diclofenac (50 mg twice daily) for group I and transdermal diclofenac patch (100 mg once daily) for group II were administered as post-endodontic analgesics for two days. Visual analogue scale (VAS) chart was used to record pain intensity scores preoperatively and at intervals of 4, 8, 12 and 24 h postoperatively for 2 days. Paracetamol 650 mg tablets were provided as rescue medication. RESULTS: There was a significant decrease in the postoperative pain intensity scores for both groups. The postoperative scores gradually decreased from day 1 to day 2 in both groups. Twelve out of sixteen patients who had received diclofenac tablets complained of gastric discomfort. CONCLUSION: Transdermal diclofenac patch was as effective as an oral diclofenac tablet and can be used as an alternative and effective analgesic for post-endodontic pain management, especially in patients with gastric discomfort.

Isolation and genetic characterization of mutans streptococci associated with dental caries in rural field practice of a dental institution: In vivo study.

BACKGROUND: Streptococcus mutans is well-known causative microorganism in the development of dental caries because they drop the plaque pH and produce acids from carbohydrates and survive in the acidic environment. It is now evident that knowledge of the bacteria enforces empirical approach to therapy, then specific antimicrobial therapy that might allow more conservative treatment options. Over the past few decades, there has been a remarkable increase in the prevalence rate of dental caries among children and the elders. Genotypic methods help in the detection and manipulation of nucleic acids which allows microbial genes to be examined directly. AIM: The aim of this study is to isolate and characterize S. mutans from rural population and to obtain genomic DNA and screen DNA band pattern. METHODOLOGY: A total of 80 plaque samples were collected from the buccal surfaces of maxillary and lingual surfaces of mandibular first molar with carious teeth in patients at a rural outreach center in Chikkaballapur district, Karnataka. Among these, 48 clinical isolates of S. mutans were recovered. Further, genomic DNA was extracted from all the positively isolated strains including the standard strain (microbial type culture collection 497), and stored at 4°C in tris EDTA buffer (TE). To analyze the molecular heterogeneity of the clinical strains, polymerase chain reaction (PCR), and restriction fragment length polymorphism was performed using restriction enzymes Hind III and Hae III. Using agarose gel electrophoresis, genomic DNA band pattern was analyzed. RESULTS: Statistically significant difference was seen in the "dex" gene collected from sample DNA and standard DNA in three different parameters (S. mutans 497). CONCLUSION: Genomic DNA of S. mutans was successfully isolated from the rural population. Dex gene was successfully amplified using PCR. Hae III enzymes successfully digested PCR amplicons and the fragments exhibited visible heterogeneity.

The effect of 2% chlorhexidine on the bond strength of two different obturating materials.

The bond strength of ActiV GP and gutta-percha/AH Plus after using 2% CHX as final rinse was evaluated in this study. According to the final irrigation regimen forty roots were divided into two groups (n = 20) randomly: Group 1-5 ml of 17% EDTA; Group 2-5 ml of 17% EDTA followed by 5 ml of 2% chlorhexidine gluconate (CHX). Based on the obturation system the two groups were further subdivided into two subgroups (n = 10). The roots were horizontally sectioned from the coronal and midthird sections for measuring the push-out bond strength. CHX/AH Plus (2.795 ± 0.42 MPa) and EDTA/ActiV GP (1.489 ± 0.117 MPa) recorded the highest and lowest mean bond strength values respectively. It was concluded that when 2% CHX was used as a final irrigation rinse the bond strength of both gutta-percha/AH Plus and ActiV GP obturation system improved significantly.

Diagnosis demystified: CT as diagnostic tool in endodontics.

Diagnosis in endodontics is usually based on clinical and radiographical presentations, which are only empirical methods. The role of healing profession is to apply knowledge and skills towards maintaining and restoring the patient's health. Recent advances in imaging technologies have added to correct interpretation and diagnosis. CT is proving to be an effective tool in solving endodontic mysteries through its three-dimensional visualisation. CT imaging offers many diagnostic advantages to produce reconstructed images in selected projection and low-contrast resolution far superior to that of all other X-ray imaging modalities. This case report is an endeavour towards effective treatment planning of cases with root fracture, root resorption using spiral CT as an adjuvant diagnostic tool.