Chapter 2
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Diode laser overview: how it is done and how to manage it E. Ruga
Approaching the use of lasers in dentistry requires a preliminary discussion about the technical aspects of this “new” method. The construction aspects of the recent diode lasers will be briefly described below, focusing attention on their functions and possible clinical implications, so as to guarantee the operator a more effective and aware use experience. Each medical laser unit consists of several essential components (" 2.1), which are fundamental respectively for the production, emission and transmission of the laser beam. According to the specific field of application, some units may differ in the type and specifications of the components. Units intended for intensive use and operating at high power ratings, for example, differ in shape, size and technical specifications compared to simpler and cheaper systems designed for applications requiring low power. Fixed systems with larger dimensions still differ in construction characteristics and technical specifications compared to portable and transportable systems. The diode laser is a semiconductor laser, whose components, now increasingly miniaturized, frequently allow easy transport of the device.
A laser is essentially made up of an active medium, i.e. the element or substance that supplies the atoms, which, invested by energy emitted from an external source (pumping system), will absorb photons, which will transfer electrons from a given energy level to a higher one.1 The pumping system is represented, in the case of a diode laser, by the electric current. The active medium is confined to a structure, called “optical cavity” or “optical resonator”, which will allow the spontaneously emitted photons to trigger the stimulation mechanism and to generate the laser beam, once a certain threshold is exceeded (! 2.1). Each element will be characterized by specific energy levels and the photons emitted will, consequently, be characterized by specific energy, frequency and wavelength.2 " 2.1 Essential components of diode laser Main unit (including optical cavity and core) Remote control unit Energy source (pumping system) Means of conduction
