There are any number of sources of information on the internet, but for starters, for further information on Dental Occupation Ergonomics, see

Simmer-Beck, Melanie, Branson, Bonnie G., Mitchell, Tanya Villalpando, Holt, Lorie  Comparison of Tactile Discrimination Associated with Varying Weights of Explorers
J Dent Educ. 2007 71: 687-693

Simmer-Beck, Melanie ; Bray, Kimberly K. ; Branson, Bonnie ; Glaros, Alan ; Weeks, Jeff   Comparison of Muscle Activity Associated with Structural Differences in Dental Hygiene Mirrors        J Dent Hygiene, 2006

 

Barbara Bennett, CDA, RDH, MS       All About Hand Instruments                       Dimensions of Dental Hygiene. November 2007

Anne Guignon   INSTRUMENT DESIGN: Understanding the Fine Details                       RDH  September 12, 2005

Tabitha Tavoc, RDH, MEd, and Marylou E. Gutmann, RDH, MA   Making the Principles of Ergonomics Work for You of Dental Hygiene. January 2005;3(1):16-18, 20-21. 

 

ADA’s Council on Dental Practice      An Introduction to Ergonomics: Risk Factors, MSDs, Approaches and Interventions   2004 American Dental Association