Methods: Forty extracted teeth with loss of connective tissue attachment into the middle third of the roots were washed and embedded in plaster. A total of 40 working scaling strokes were applied. Low forces were used in 30 teeth and high forces in 10 teeth.
Results: Mean cumulative loss of root substance across 40 strokes was 148.7 microns at low forces, and 343.3 microns at high forces. Substance removal per stroke during strokes 1 to 5 was 6.8 microns using low forces and 20.6 microns using high forces.
Conclusions: High forces remove more root substance. Loss of root substance per stroke becomes less with increasing numbers of strokes.
For more information please refer to:
J Periodontol 1991 Dec;62(12):750-4.
Root substance removal by scaling and root planing
U Zappa 1 , B Smith, C Simona, H Graf, D Case, W Kim