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Ultrasonic and sonic Instrumentation. Darby pgs 473 – 492 Also Module 24 Fundamentals of Periodontal Instrumentation. Mechanized instrumentation. Mechanical action = vibration of the tip – results in deposit removal Clinical power – ability to remove deposit under load
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Ultrasonic and sonic Instrumentation Darby pgs 473 – 492 Also Module 24 Fundamentals of Periodontal Instrumentation
Mechanized instrumentation • Mechanical action = vibration of the tip – results in deposit removal • Clinical power – ability to remove deposit under load • Tip action provides clinical power and is dependent on the: • Stroke • Frequency type of tip motion • Angulation of the motion against the tooth surface
Mechanized instrumentation • Load = resistance on an instrument tip when placed against the calculus deposit or tooth surface • Cavitation – action created by the formation and collapse of bubbles in the water by high-frequency sound waves surroundings an ultrasonic tip • Results in lavage = the therapeutic washing of the pockets and root surface to remove endotoxins and loose debris (irrigation)
Mechanized instrumentation • Acoustic microstreaming = occurs because agitation in the fluids surrounding a rapidly vibrating ultrasonic tip has the potential to destroy or disrupt bacteria
Water Cooled Instrument Tips • Electronically powered devices use water-cooled instrument tips. Water constantly exists near the point of the instrument tip.
Rapid energy vibrations of the powered instrument tip fracture calculus from the tooth surface and clean the environment of the periodontal pocket
Two types of electronically powered devices: sonic and ultrasonic Sonic handpieces attach to the dental unit’s compressed air line. Ultrasonic devices have an electric generator and do not need to be connected the the dental unit. Two types of ultrasonic devices are the magnetostrictive and the piezoelectric.
Slim-tip design • In the late 1980’s slim-diameter instrument tips are developed for electronically powered devices. Slim diameter tips are significantly smaller thatn the working end of a standard Gracey curet.
Mechanisms of Action • Frequency • Electronically powered devices use an electric current to produce rapid vibrations of the instrument tip • Frequency refers to how many times the electronically powered instrument tip vibrates per second.
Frequency • 1. When the wiper setting is on low, the wipers go back and forth only a few times per minute. Similarly, when the frequency of a powered instrument is low, the instrument tip vibrates fewer times per second. • 2. Conversely when high the tip vibrates more times per second.
Stroke=amplitudePower knob changes the length of the strokeHigher power delivers a longer, more forceful stroke.
Controlling stroke, frequency, and water flow • Power = length of stroke (no difference in medium or high as far as effectiveness) • Higher power may cause discomfort or damage tooth surface.
Tuning (frequency) • Tuning on ultrasonic devices may be either manual or automatic. • In addition to the frequency tuning of the ultrasonic generator, each magnetostrictive ultrasonic instrument tip has its own natural vibration level. (resonant frequency)
Sonic devices • Sonic electonically powered devices consit of a hadpece that attaches to the dental unit’s high-speed handpiece tubing and interchangeable instrument tips
Ultrasonic Instruments • Convert electrical energy into mechanical energy in the range of 18,00 to 50,00 vibrations per second • Ultrasonic = non-audible range of acoustical vibrations that are a unit of frequency referred to as cycles per second (CPS) or hertz (Hz)
Piezoelectric ultrasonic devices • Composed of a portable electronic generator, a handpiece, and instrument inserts.
Magnetostrictive Ultrasonic Devices • Contains electronic generator, handpiece, and interchangeable instrument inserts. • Inserts fit into the handpiece • Two kilohertz (kHz) options: 25kHz and 30 kHz • 25kHz = work ONLY with 25 kHz devices • 25,000 cycles per second • Longer stoke length • Longer in length than a had instrument • 30 kHz = work ONLY with 30 kHz devices • 20,000 cycles per second • Shorter stroke length • About the same length as a hand instrument
Insert • Insert selection considerations - • Designs for periodontal debridement • Compatibility with other units in the practice setting • Compatibility with the frequency (kHz) • Method of fluid delivery
Metal stack – converts electrical power into mechanical vibrations • O-ring – a seal that keeps water flowing through the insert rather than flowing out the handpiece • Handle grip – portion of the insert grasped by the clinician during instrumentation • Water outlet – provides water to the instrument tip • Working-end – portion of the instrument insert used for calculus removal and deplaquing
Standard inserts • Used for supragingival or subgingival debridement of the following: • Light, moderate, or heavy calculus • Bacterial plaque biofilm • Extrinsic stain orthodontic cement
Next week • Tues – • Finish lecture on power driver scalers • Practice on typodonts in clinic • Weds – test on power driven scalers • Begin air polishing and bleaching pgs 447-456 in Darby
Slim-Diameter straight tip • Designed for use on: • Anterior root surfaces • Posterior root surfaces that are 4mm or less apical to the cemento-enamel junction
Slim-diameter curved tips • Similar in design to a curved furcation probe • Designed fo use on: • Posterior root surfaces located more than 4mm apical to the CEJ • Root concavities and furcations on posterior tooth surfaces
Power Settings • Always use the lowest effective power setting. • High power setting should be avoided – studies have shown no more effective that medium • Consider the following criteria • Size of calculus deposit • Diameter of instrument tip
Energy Production by working-end surfaces Adaptation • Point of the tip should never be adapted to the tooth surface. Could damage the tooth. • Face of the tip should not be adapted to the tooth surface because of the high amount of energy it produces. Face could also damage tooth. • Back of the tip can be adapted to the tooth surfaces • Lateral surfaces of the tip are recommended with all sonic, piezoelectric and magnetostrictive ultrasonic instruments
Active Tip Area • It is the vibration energy of a powered instrument tip that is responsible for calculus removal. The portion of the instrument tip that is capable of ding work is called the active tip area. • The higher the frequency of an electronic device the shorter the active tip area
Active Tip Area • The power for calculus removal is concentrated in the active tip area {the last 2 to 4 mm of the tip.}
Instrument tip wear and replacement • The working end should be inspected regularly for signs of wear. • With use, the instrument tip is worn down. • As the instrument tip wears, effectiveness decreases.
Contraindications • Communicable disease • High susceptibility to infection • Respiratory risk • Pacemaker • Difficulty in swallowing or prone to gagging • Age • Oral conditions
Communicable disease • Individuals with communicable diseases that can be disseminated by aerosols • Hepatitis • Tuberculosis • Respiratory infections • HIV positive
High susceptibility to infection • Individuals with a high susceptibility to opportunistic infection that can be transmitted by contaminated dental unit water or aerosols such as those with uncontrolled diabetes or organ transplants, debilitated individuals with chronic medical conditions, or immunosuppresssed individuals
Respiratory risk • Individuals with respiratory disease of difficulty in breathing • History of emphysema • Cystic fibrosis • asthma • This patient would have a high risk of infection if pt. would aspirate bacterial plaque into lungs
Pacemaker • The American Academy of Periodontology that DHCW avoid exposing patients with cardiac pacemakers to magnetostrictive devices • Piezoelectric ultrasonic devices do not interfere with pacemaker functioning
Difficulty in swallowing or prone to gagging • Individuals with multiple sclerosis; • Amyotrohic lateral sclerosis • Muscular dystrophy • paralysis
age • Primary and newly erupted young children have large pulp chambers that are more susceptible to damage from the vibrations and heat produced by ultrasonic instrumentation.
Oral conditions • Avoid contact of instrument tip with hypersensitive teeth, porcelain crowns, composite resin restorations, demineralized enamel surfaces, or exposed dentinal surfaces. Not for use in those with titanium implants, unless the working-end of the powered instrument is covered with a specially designed plastic sleeve.
Flushing of water tubing • Self-contained reservoir • Point-of-use filter • Flush the water tubing • 2 mins. At start of day • 30 secs. Between pts.
