Investigations into the use of an ultrasonic chisel to cut bone. Part 1: Forces applied by clinicians.
OBJECTIVE
To measure in vitro the direction and force of applied loads applied by clinicians when using both a conventional slow surgical handpiece (CH) and an ultrasonic chisel (USC) for cutting bone.


METHODS
Five clinicians were asked to cut bovine bone using either an USC or a CH. The bone was placed on a force measurement system that could measure both longitudinal and downward loads. The rate of cut was calculated over a fixed time-period and the depth of cut measured using a penetratometer.


RESULTS
The magnitude of the longitudinal forces generated varied between 1.48 and 3.22 N (USC) and 0.04 and 4.56 N (CH). The CH had a pulling force directed towards the operator. Both instruments produced a similar range of downward forces although there was intra- and inter-operator variability. The rate of cut varied in a similar manner, however, the CH produced a significantly greater depth of cut (p < 0.05).


CONCLUSIONS
The force measurement system demonstrated differences in the way clinicians used the USC and CH instruments to cut bone. Of the two cutting methods investigated, the rotary bur is more efficient than the ultrasonic chisel. An ultrasonic chisel does cut bone in a different manner from a conventional bur and clinicians may require training before using it clinically.
Khambay
B S
BS
School of Dentistry, University of Birmingham, UK.
Walmsley
A D
AD
D000704:Analysis of Variance; D000818:Animals; D002417:Cattle; D003762:Dental Instruments / Q000706:statistics & numerical data; D003799:Dental Stress Analysis / Q000295:instrumentation / Q000706:statistics & numerical data; D005069:Evaluation Studies as Topic; D005269:Femur / Q000601:surgery*; D066298:In Vitro Techniques; D015588:Observer Variation; D019647:Oral Surgical Procedures / Q000295:instrumentation; D014464:Ultrasonic Therapy / Q000295:instrumentation* / Q000706:statistics & numerical data