Management of Sub-gingival Fracture of Tooth by Multi-disciplinary Approach

Dental trauma is commonly occur in children and may involve adult person also. In permanent dentition crown fracture is common and it may be uncomplicated or complicated. Complicated crown-root fractures require a multidisciplinary treatment modality for longterm success. Here we presented multidisciplinary treatment of a traumatized permanent maxillary incisor of a young male patient where oblique tooth fracture involved coronal pulp. As more than 50% of the crown and palatal coronal part of the root had been fractured and the tooth could not be properly isolated during endodontic procedure which is essential for success of root canal treatment. An intra-canal wire hook was cemented in the root canal and attached to another wire fixed to the adjacent teeth. With the help of elastic band attached with hook the fractured tooth fragment was extruded to create clinical crown. Finally, gingival re-contouring was performed to establish optimum biological width. At last, porcelain fused to metal crown was placed and the patient was comfortable both esthetically and functionally.International Journal of Human and Health Sciences Vol. 03 No. 03 July’19. Page: 165-168

Electrode for selective recording of electromyograms from intercostal muscles

An electromyogram-recording electrode is described that makes it possible to record separately the electrical signals generated within two closely approximated muscle layers. The device consists of two bipolar wire hook electrodes embedded in opposite faces of a thin laminated plastic wafer. The middle lamina of the wafer is a sheet of metal foil that shields the electrical field on one side of the wafer from the bipolar electrode on the other side. The device was tested by inserting it from the inside of the chest wall between the internal and external intercostal muscle layers. Signals from the two muscle layers were clearly separated. Single motor unit spikes were attenuated by factors ranging from 41 to 2.4. The device can be implanted with minimal trauma to surrounding muscles and is suitable for chronic animal experiments.

A new method for the absolute determination of frequency

The new method for the absolute determination of acoustical frequencies described in this paper possesses several useful features. Among these are: ( a ) the rapidity with which very accurate results may be obtained by its use, ( b ) its practical convenience and simplicity, ( c ) the inexpensiveness of the apparatus required, and ( d ) its availability for use with any of the standards of time ordinarily available in a physical laboratory, i. e ., a “seconds” or “half-seconds” pendulum clock, a “half-seconds” chronometer, or even merely a good stop-watch. The method is the outcome of an investigation undertaken at my suggestion by Mr. Dey, and its value has been proved in an extensive series of tests carried out by him. The principle on which the method is based is that of the maintenance of oscillations of sub-synchronous frequency by a periodic field of force, and is applied in practice in the following manner:— A pendulum formed of an iron rod 0.5 cm. diameter hangs vertically from a simple wire-hook suspension. A brass bob slides on the pendulum and is capable of being fixed in any desired position. The length of the pendulum is either 35 cm. or 100 cm., so that with the bob in a suitable position the free period of oscillation is roughly either one second or two seconds as desired.