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Practical employment №4.
SLEEVES AND TIPS USED IN STOMATOLOGY. RULES OF THEIR INSTALLATION
Development of the rotating equipment
Presence of methods of removal and formation of fabrics of tooth is necessary for their restoration. The data of archeological excavations testifies what to treat teeth people has begun for 5 000 years BC, but it is very little known about what they used for this purpose methods and the equipment [14]. On fig. 5.20 and 5.21 the first manual pine forests are presented. Search of more perfect energy sources and means for fixing and control over cutting tools in many respects promoted working out современ мого the cutting equipment. Finally it has led to use of the demountable metal or abrasive tools applied in rotating tips, usually set in motion compressed air.
The tip is a device for fixing of the rotating tools, transferring to them energy and position defining them in an oral cavity. Tips and cutting with them cutting and polishing tools used with them happen two types: direct and angular (fig. 5.22). The majority of methods of preparation of teeth has been developed last hundred years [34]. The effective equipment for removal (or preparations) enamels has appeared only in 1947 when for the first time have started to use speed of rotation of tools of 10 000 rpm, along with new карбидными pine forests and diamond tools. Since 1953 improvement of a design of tools and materials for созда ния tips and tools has led to occurrence of the effective and easily sterilised equipment. In many respects thanks to efforts of manufacturers and stomatologists. The basic development cycles of the rotating stomatologic equipment are presented to tab. 5.1.
One of the most outstanding achievements was оявление the electric motor as a source •нергии rotations in 1874. It has been included in structure of stomatologic installation and 1914 [35]. The first tips and speed of their rotation (a maximum of 5 000 rpm) remained invariable till 1946 (fig. 5.23). The steel pine forests used at that time, could not delete effectively •маль even at the appendix of the big force. To the dress
The raised vigilance concerning a transmission of infection from the patient to the patient has caused attention to other aspects of work of tips. Last improvements of direct and angular tips allow to spend their repeated sterilisation by several methods. However sterilisation leads to certain damage of some particles of metal of a tip that causes in its more frequent service and repair. Other improvements of angular tips are the small size of a head, the big force of a twisting moment, smaller noise level and more perfect mechanisms of transfer. Since 1955 angular tips began to be supplied with an aero-aquatic irrigation which provides cooling, clearing and the best visibility [32] (fig. 5.27). The majority of modern angular tips have also fiber-optical illumination on a tip.
At high speed effective for препари рования speed of rotation of the tool on atop ности can be reached at use 6о лее small and multipurpose tools. Such speed is used for preparation that - бов and removals of old restorations. Possibility of regulation of speed of rotation does tips more многофумкциомаль ными. For control over a transmission of infection all stomatologic tips sterilise now, but it is connected with some complexities. Frequent sterilisation can negatively influence the characteristic of tips (service life, capacity, speed of work of the turbine, transfer of fiber-optical light, balancing, noise level, transfer, visibility of a corner, межокклюзионная cleanliness, a water irrigation) [23]. The majority of tips after sterilisation need repeated greasing owing to what in the beginning of work oil can be sprayed. Therefore it is recommended to include a tip for some seconds before the work beginning as oil hit on a tooth fabric can break performance of some techniques, for example adhesion of composites.
Despite the fact that. That интактную the tooth fabric can be removed at tool rotation on low speed. It will be травматично both for the patient, and for the stomatologist. Preparation on low speed is inefficient, occupies a lot of time and demands the appendix concerning the big force. It leads to heating of a place of preparation and causes vibration of the tool with low often - ои and the big amplitude. Heating and vibration are principal causes of occurrence of discomfort at the patient. At low it is fast - ии rotations pine forests have propensity slide off »area of preparation and break at •том проксимальные edges or a tooth surface, к.юме that, карбидные pine forests do not serve long, a hook as their fragile sides easily break on low« forgive. Works much of these lacks on low speed do not concern performance of other operations which have been not connected with preparation of teeth. ‘ "•1ная speed of work of tools is used for clearing of teeth, sometimes for removal ka - п '.юзных fabrics, polishing and polishing. Probability of overheating prepared atop ностей. Work possibility on low speed яв ляется very valuable auxiliary quality of the tool for performance of many stomatologists ческих manipulations.
For control over a transmission of infection all stomatologic tips sterilise now, but it is connected with some complexities. Frequent sterilisation can negatively influence the characteristic of tips (service life, capacity, speed of work of the turbine, transfer of fiber-optical light, balancing, noise level, transfer, visibility of a corner, межокклюзионная cleanliness, a water irrigation) [23]. The majority of tips after sterilisation need repeated greasing owing to what in the beginning of work oil can be sprayed. Therefore it is recommended to include a tip for some seconds before the work beginning as oil hit on a tooth fabric can break performance of some techniques, for example adhesion of composites.
Modern stomatologic installations have various types of drives.Рукав the rigid is intended for transfer of rotating movement from the drill electric motor to a tip spindle on which the cutting tool fastens.
The sleeve consists of the holder of the tip, the first and second knee, cores.
The electric drill gives speed of rotation of a pine forest from 10000 to 30000 об.мин and turbine to 500000 об.мин.
The basic дейсвующей a part of a flexible sleeve is the elastic long spiral forming rotating core.
Tips serve for fastening of cutting tools and transfer of rotation by it from a pine forest.
Расчитан on rotation of a pine forest with a speed до30000 об.мин. Has an angular rotary head, the platen, a sliding sleeve, a protective sleeve, a latch, the screw of a latch conducting a shaft. A fixing nut of an angular head, cross-section
From a drive of installation rotation is transferred to cutting tool by means of a tip.
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