Magnitude and Reproducibility of Forces Generated by Clinicians during Laceback Placement

Abstract

Objective

To determine the magnitude and reproducibility of forces generated by clinicians during laceback placement using a force-measuring typodont.

Setting

An in vitro investigation.

Materials and methods

An in vitro typodont model was developed, which incorporated strain gauges attached to a personal computer to allow measurement of the force generated on application of lace backs. Ten operators were instructed to place lace backs five times, on two separate occasions (T1 and T2). Inter-operator and intra-operator forces produced at T1 and T2 were compared.

Main outcome measures

Forces generated by laceback placement.

Results

The forces generated by clinicians ranged from 0 to 11.1 N. There were significant differences in the mean forces generated by the different operators (P < 0.001), with differences between time points not being consistent across all operators (P < 0.001). Some operators were more consistent than others in the forces generated.

Conclusion

In vitro, there was a large inter-operator variation in the forces produced during laceback placement. With the in vitro model used in this study, few operators applied similar forces when placing lace backs on two separate occasions.