<prompt> In orthodontic treatment, in order to avoid injuries to thetissues, the forces applied generally should not exceed:Capillary blood pressureDiastolic arterial blood pressureMasticatory forcesSystolic arterial blood pressure  <response>: It has been stated by Oppenheim and Schwarz, a result of their experiments, that optimum orthodontic force would be equivalent to the capillary pulse pressure or 2026 gcm2 of root surface. With this light force, tooth movement would be by direct osteoclastic activity in the area of greatest pressure; undermining resorption would not occur. The optimum force should be one that moves the tooth most rapidly in the desired attitude and direction with the least tissue damage and the slightest amount of pain. 