Instruments and methods for the quantitative measurement of factors affecting hygienist/dentist efforts during scaling and root planing of the teeth.

Manual calculus debridement through scaling accounts for a significant proportion of hygienist efforts in dental and periodontal practices. Despite this, little is quantitatively known concerning the effects of instruments, technique and treatments on debridement (scaling) efficiency or efficacy. The total work effort expended by therapists in calculus debridement results from the sum of the efforts associated with each scaling stroke. Each scaling stroke, in turn, is affected by a variety of physical forces, including those in the control of the therapist and those intrinsic to the calculus substrate. The development of procedures and treatments to facilitate easier calculus removal requires consideration of the physical and technique-related factors which contribute to hygienist effort. Instruments have recently been developed which can quantitatively measure force dynamics associated with scaling procedures, including both therapist-applied forces and forces developed due to the extreme hardness and tenacity of supra- and subgingival calculus deposits. The scaling instrument developed to quantitatively record developed forces in scaling, the Quanticalc, can be used for the assessment of techniques and treatments which can soften calculus, facilitating easier debridement. The device can also be used to instruct therapists on factors contributing to surface roughness and tactile response to these factors. The scaling instrument developed to quantitatively measure therapist applied forces in scaling, the Zappa device, can be used for assessment of techniques which can increase the efficiency of calculus removal with minimal damage to sound root substance. In this paper, the force dynamics associated with manual scaling procedures of dental professionals are defined. These force dynamics account for the total work expended by hygienists and other professionals in the important task of calculus removal. Using this as a foundation, the design, use, calibration and clinical applications of these newly developed scaling-force measurement systems are described.

A machine for sawing 80-micrometer slices of carious enamel.

Design and construction of a machine that cuts 80-microns slices of sound and carious dental enamel and other calcified tissues is described. These slices can be used for quantitative microradiographic studies. Preparation takes minutes. Thickness for a given slice is uniform within 2 microns, mean thickness is within 4 microns of the intended value and roughness is about 0.1 micron. Commercial components have been used where possible. Information is provided to permit purchase of the components of the machine and its construction in the average university workshop.