A comparative evaluation of the efficacy of manual, magnetostrictive and piezoelectric ultrasonic instruments: an in vitro profilometric and SEM study

OBJECTIVES: The debridement of diseased root surface is usually performed by mechanical scaling and root planing using manual and power driven instruments. Many new designs in ultrasonic powered scaling tips have been developed. However, their effectiveness as compared to manual curettes has always been debatable. Thus, the objective of this in vitro study was to comparatively evaluate the efficacy of manual, magnetostrictive and piezoelectric ultrasonic instrumentation on periodontally involved extracted teeth using profilometer and scanning electron microscope (SEM). MATERIAL AND METHODS: 30 periodontally involved extracted human teeth were divided into 3 groups. The teeth were instrumented with hand and ultrasonic instruments resembling clinical application. In Group A all teeth were scaled with a new universal hand curette (Hu Friedy Gracey After Five Vision curette; Hu Friedy, Chicago, USA). In Group B Cavitron(TM) FSI - SLI(TM) ultrasonic device with focused spray slimline inserts (Dentsply International Inc., York, PA, USA) were used. In Group C teeth were scaled with an EMS piezoelectric ultrasonic device with prototype modified PS inserts. The surfaces were analyzed by a Precision profilometer to measure the surface roughness (Ra value in µm) consecutively before and after the instrumentation. The samples were examined under SEM at magnifications ranging from 17x to 300x and 600x. RESULTS: The mean Ra values (µm) before and after instrumentation in all the three groups A, B and C were tabulated. After statistically analyzing the data, no significant difference was observed in the three experimental groups. Though there was a decrease in the percentage reduction of Ra values consecutively from group A to C. CONCLUSION: Within the limits of the present study, given that the manual, magnetostrictive and piezoelectric ultrasonic instruments produce the same surface roughness, it can be concluded that their efficacy for creating a biologically compatible surface of periodontally diseased teeth is similar

Raman characterization and chemical imaging of biocolloidal self-assemblies, drug delivery systems, and pulmonary inhalation aerosols: A review

This review presents an introduction to Raman scattering and describes the various Raman spectroscopy, Raman microscopy, and chemical imaging techniques that have demonstrated utility in biocolloidal self-assemblies, pharmaceutical drug delivery systems, and pulmonary research applications. Recent Raman applications to pharmaceutical aerosols in the context of pulmonary inhalation aerosol delivery are discussed. The “molecular fingerprint” insight that Raman applications provide includes molecular structure, drug-carrier/excipient interactions, intramolecular and intermolecular bonding, surface structure, surface and interfacial interactions, and the functional groups involved therein. The molecular, surface, and interfacial properties that Raman characterization can provide are particularly important in respirable pharmaceutical powders, as these particles possess a higher surface-area-to-volume ratio; hence, understanding the nature of these solid surfaces can enable their manipulation and tailoring for functionality at the nanometer level for targeted pulmonary delivery and deposition. Moreover, Raman mapping of aerosols at the micro- and nanometer level of resolution is achievable with new, sophisticated, commercially available Raman microspectroscopy techniques. This noninvasive, highly versatile analytical and imaging technique exhibits vast potential for in vitro and in vivo molecular investigations of pulmonary aerosol delivery, lung deposition, and pulmonary cellular drug uptake and disposition in unfixed living pulmonary cells