powered instrumentation

dental hygiene care

aims to prevent, arrest, control, or eliminate the infection in the gingiva or periodontal tissues

powered instrumentation

uses rapid energy vibrations of a powered instrument tip to fracture calculus deposits from tooth, disrupt plaque biofilm and flush out bacteria from periodontal pocket

periodontal debridement

-Mechanical removal of deposits

-Superficial removal of cementum

-Creation of a biologically acceptable root surface

-Assessment of soft tissue response

indications of powered instrumentation

-Removal of calculus and plaque biolfilms

-Pocket Penetration

-Access to furcations

-Irrigation

-Shorter Instrumentation time

-Conservation of tooth structure

contraindications for powered instrumentation

-Unshielded cardiac pacemaker

-Communicable diseases

-Medically compromised patients

-Patients at respiratory risk

-Patients with dysphagia or prone to gagging

-Titanium implants

-Certain restorative materials

-Demineralization

-Hypersensitive teeth

-Primary and newly erupted teeth of young children

limitations of powered instrumentation

-Clinician skill level

-Reduced Tactile sensitivity

-Infection Control

-Aerosol production

-Musculoskeletal & auditory damage

blended approach

Long term goals of successful nonsurgical periodontal therapy are achieved through both manual and ultrasonic instrumentation

modes of action

-mechanical

-irrigation/ lavage

-acoustic microstreaming or acoustic turbulence

-cavitation

mechanical

rapid vibrations of tip create microfractures in calculus

irrigation/ lavage

-water irrigation washes toxic products and free-floating bacteria from the pocket

-water required in handpiece to keep tip cool

acoustic microstreaming/ acoustic turbulence

swirling effect produced within pocket by water causing removal/disruption of biofilm

cavitation

formation of tiny bubbles in water stream, when bubbles collapse, shock waves produced to destroy bacteria by tearing down cell walls

sonic

-Creates high frequency sound waves that produce vibrations

-2,000 to 6,5000 cps

-Attaches to conventional handpiece

-Driven by compressed air

-Elliptical tip movement

-All surfaces active

sonic instrument tips

-attach directly to the handpiece

-Most will have special wrenches to lock the instrument tip in place

magnetostrictive

-18,000 to 45,000cps or Hz; newer units designed to operate at 30,000cps

-Ferromagnetic transducer - rods

-Thick metal nickel strips soldered together aka: metal stack

-Elliptical

-All surfaces active

magnetostrictive devices

-composed of portable electronic generator

-has removable instrument inserts that fit into the handpiece

-two different kilohertz options, with insert to match

piezoelectric

-25,000 to 50,000 cps or Hz

-Ceramic crystals transducer

-Linear tip movement

-Lateral surfaces are active

unit parts of piezo

-electronic generator

-handpiece

-instrument tips

-Foot pedal

-Possible reservoir

occupational risks of powered instrumentation

-Contaminated aerosol production

-Preventive Measures - barrier protection, HVE, pre-procedural rinse

-Musculoskeletal damage

-Hearing loss

advantages of US instrumentation

-Reduced clinician fatigue

-Less repetitive stress

-Increased access

-Less tissue distension

-Potential for antimicrobial delivery

-Benefits of lavage

purpose of water

-Regulates volume

-Cools stack and tip

-Lubricates for easy insertion

-Flushes debris

importance of fluid

-Ultrasonic instruments MUST be cooled by fluid to prevent overheating

-Sonic tips do not overheat and do not require water for cooling

-Use of water is recommended with sonic instruments for benefits of lavage

-Fluids such as distilled water, sterile saline, stannous fluoride, and chemotherapeutic agents (antimicrobials) are commonly used with ultrasonic instruments.

lavage

-Improves healing

-Washes field for visibility

-Possible bacteriocidal effect

• Cavitational effect

• Acoustical streaming

-Too little water – most common mistake

• warm handpiece is warning sign of

• inadequate water flow through handpiece and tip

external flow tube

-a separate tube carries the water to the tip.

-The water exits the flow tube near the lower shank of the instrument tip

internal flow insert

water flows through the tip, itself, exiting closer to the “point”

frequency

-Refers to how many times the instrument tip vibrates per second.

-Powered devices use electric current to produce rapid vibrations of the instrument tip.

-Speed of movement - number of times the tip moves back and forth/cycles per second – cps

When the frequency of a powered instrument is low

the instrument tip vibrates fewer times per second.

when the frequency is high

the instrument tip vibrates more times per second

25 kHz

-25,000 cycles per second

-Longer stack length

-Longer stroke length

30 kHz

-30,000 cycles per second

-Shorter stack length

-Shorter stroke length

amplitude

-Refers to how far the instrument tip moves during a cycle

-Regulates stroke length

-Distance the tip travels

lower power

shorter, less forceful stroke

higher power

longer, more forceful stroke

low frequency and low amplitude

ideal for removal of biofilm & stain

high frequency and high amplitude

ideal for removal of tenacious calculus deposits

power settings

-Most units have high, medium, and low power settings.

-Research found NO DIFFERENCE in the effectiveness of the high and medium power settings.

-Use of the HIGH power setting is NOT recommended in most cases

-At higher power, instrument strikes tooth with more force, which is more uncomfortable for patient

-A higher power is more likely to damage tooth surface

power setting options

-Adjust for clinical efficiency

-Adjust for tip diameter

-Use lowest effective power setting

• Increased patient comfort

• Longer instrument life

How efficiently an electronically powered instrument removes calculus is determined by the:

-Instrument tip’s vibration frequency

-Stroke length

-Stroke motion

-Surface of the instrument tip in contact with the tooth

-Clinician skill

clinical considerations

-Power setting determined by type of deposit and insert design

-Thin tips on lower power should be used for slight deposits

-Mod/heavy deposits can be burnished by thin tip on low power

-Mod/heavy deposits should be removed using appropriate inserts with increase power setting

technique tips

-Tip should be constant motion w/ multidirectional strokes

-Light grasp w/ stable finger rest

-Adaptation of tip should be similar to hand instruments

-Angulation should be 0-15 degrees to tooth surface

-Light pressure applied to maintain contact with tooth

-High speed evacuation

-Water flow should have halo effect

heavy debris removal

-medium or higher power setting

-standard tip designs

light debris removal

-low to medium power setting

-thin perio designs

tip activation and insertion

-Activate prior to placement on tooth

• Alerts patient

• Eases subgingival insertion

-Keep the tip moving at all times

tip adaptation

-Parallel to tooth surface

-Tip angulation near zero degrees

-Little or no lateral pressure

technique

-The point of an powered instrument tip should never be adapted to tooth surface

-The high energy dispersed by the point could damage the tooth

bottom up approach

-Calculus removal takes place from the base of the pocket toward the CEJ.

-Curet positioned under deposit

top down approach

-Calculus removal takes place from the top of the deposit working in an apical direction

-powered instrument positioned above deposit

sweeping motion

-used on light deposits and for deplaquing

-used with gentle pressure

common mistake using ultrasonic is:

-heavy or moderate pressure against tooth or calculus

-Moderate or firm pressure decreases effectiveness of powered instrument tip

-Firm pressure will actually stop tip from vibrating

universal (straight) tips

-All accessible surfaces

-Most effective on:

• Buccal and lingual surfaces of all teeth

• Interproximal surfaces of all teeth

curved (right and left) tips

-Interproximal surfaces of posteriors

-Furcations

-Tight contacts

-Malpositioned molars

-Concave surfaces

instrumentation fundamentals

-Select insert design

-Adapt tip parallel to tooth

-Use light lateral pressure

-Keep tip moving at all times

-Let the tip do the work

wear guide

-1mm loss can result in 25% efficiency loss

-2mm loss can result in 50% efficiency loss