“…In agreement with other studies (2,4,5,8,12,13,17,20), the results of this study showed that OMS length has no bearing on rate of failure (p=0.9113) and also, no difference was found indicating failure when the mandibular plane angle (4,9,11,16) was used to classify the three facial patterns (p=0.7522), which disagrees with studies that used other references and found differences between patients with different vertical characteristics (4,9,11,16). Corroborating Kim et al (11), and very close to the significance level, no significant differences were found in the different directions of force application deployed to achieve the desired type of movement (p=0.0584), although other studies have found a higher rate of failure in vertical forces vs. horizontal forces (4,8) and in forces used for tooth uprighting (9). Thus, the facial pattern and direction of force present unclear influence on the failure rate, and more studies with larger sample sizes are needed to address these features.…”