Current controversies over bioresorbable scaffolds

The field of coronary intervention has made great strides since the first balloon angioplasty performed by Andreas Gruentzig in Zurich in 1977.1 Starting with that case, coronary interventional data has been rigorously generated through single-center and multicenter registries and randomized trials, allowing for remarkably broad-sweeping, evidence-based, leapfrog improvements in technology and outcomes in just a few decades. In this paper we outline the natural evolution from "plain old balloon angioplasty" (POBA) to bioresorbable scaffolds (BRS) and other novel therapies, and discuss the emerging data regarding the promise of BRS as well as controversies and residual concerns regarding this technology.

Coherent synthesis of ultra-broadband optical parametric amplifiers

We report on coherent synthesis of two ultra-broadband optical parametric amplifiers, each compressed by chirped mirror pairs, resulting in almost-octave-spanning (520-1000 nm) spectra supporting nearly single-cycle sub-4 fs pulse duration. Synthesized pulse timing is locked to less than 30 as by a balanced optical cross-correlator. The synthesized pulse is characterized by two-dimensional spectral interferometry and has a 3.8 fs duration.

Self-injurious behavior and foreign body entrapment in the root canal of a mandibular lateral incisor

Self-injurious behavior is a deliberate alteration or damage without suicidal intent. Herein, we report a patient who had caused intentionally self-trauma to his left lower permanent canine and placed a long metallic foreign body into the root canal. History revealed a habit of placing metallic objects in the form of stapler pins into the mouth, but closer examination revealed the habit to be more as a method of self-injurious behavior. Following an episode of severe pain, the tooth was endodontically treated after removal of the foreign body that was corroding. Clinical significance of the case report is that the patient may just be put off as having a habit of inserting foreign objects into the mouth, but the behavior was more self-injurious in nature.

Optical Cherenkov radiation by cascaded nonlinear interaction: an efficient source of few-cycle energetic near- to mid-IR pulses

When ultrafast noncritical cascaded second-harmonic generation of energetic femtosecond pulses occur in a bulk lithium niobate crystal optical Cherenkov waves are formed in the near- to mid-IR. Numerical simulations show that the few-cycle solitons radiate Cherenkov (dispersive) waves in the λ = 2.2 - 4.5 μm range when pumping at λ₁ = 1.2 - 1.8 μm. The exact phase-matching point depends on the soliton wavelength, and we show that a simple longpass filter can separate the Cherenkov waves from the solitons. The Cherenkov waves are born few-cycle with an excellent Gaussian pulse shape, and the conversion efficiency is up to 25%. Thus, optical Cherenkov waves formed with cascaded nonlinearities could become an efficient source of energetic near- to mid-IR few-cycle pulses.

Comparative evaluation of the efficacy of different concentrations of chlorhexidine mouth rinses in reducing the mutans streptococci in saliva: an in vivo study

BACKGROUND

Is low-concentration chlorhexidine effective against reducing the mutans streptococci (MS) in saliva?

AIM

To compare the efficacy of different concentrations of chlorhexidine mouth rinses, i.e. 0.02%, 0.06% and 0.12%, in reducing the mutants streptococci count in saliva.

DESIGN

Forty subjects in the age group of 12-14 years were selected from the schools of Chennai and were equally divided into four groups. The first three were study groups and the fourth group was the control group. The subjects were instructed to rinse with a measured amount of mouth rinse for 1 min, twice-daily, for 1 week. Salivary samples were collected at baseline and 1 week after mouth rinsing with various concentrations and were cultured on MSB agar. The number of MS colonies was counted on agar medium under anaerobic conditions.

RESULTS

The results of the study confirmed that children using chlorhexidine of concentration 0.12% showed the maximum reduction in MS when compared with subjects using 0.02% and 0.06% concentrations. But, children using chlorhexidine of concentration 0.06% also showed significant reduction in MS when compared with the control group.

CONCLUSION

From the above study, we conclude that chlorhexidine used in different concentrations (0.02%, 0.06%, 0.12%) efficiently reduced the mutans count.