Comparison of occlusal balance contacts in patients treated with standard edgewise and preadjusted straight-wire appliances.

This study investigated the functional occlusion in two groups of patients treated to a Class I canine and molar relationship by fixed appliance therapy. Group A consisted of 24 patients treated with standard edgewise appliances, whereas the 15 patients in group B were treated with a straight-wire appliance. The occlusal contacts were assessed intraorally with articulating ribbon of 8 microns thick. All procedures and measurements were performed by the same examiner. The results revealed that balancing contacts were significantly more frequent in group A. In both groups, most subjects had balancing contacts between their second molars (P<.05). The prevalence of posterior protrusive contacts in group A was similar to group B. Most of the subjects in group B demonstrated canine guidance on laterotrusion, whereas in group A, the majority exhibited group function (P<.05). Mutually protected occlusion was present in an overwhelming percentage of group B, as compared to no patient in group A (P<.05). Patients treated with edgewise appliances did not exhibit ideal functional occlusal relationships, whereas most individuals after straight-wire appliance therapy had a mutually protected (ideal) occlusion.