Date of Graduation


Document Type


Degree Type



School of Dentistry


Not Listed

Committee Chair

Peter Ngan.


Objectives. To evaluate changes to the WALA Ridge when subjected to orthodontic treatment using customized WALA Ridge archwires and preformed archwires, and ascertain trends within the United States amongst practicing orthodontists regarding arch form selection. Methods. 10 control subjects, 20 customized archwire subjects, and 20 preformed archwire subjects were compared using pre and post treatment mandibular casts for the experimental groups and two timepoint mandibular casts with two years between collection for the control group. Dental and Dentoalveolar changes were then measured from T1 to T2 for each of the groups. Furthermore, an electronic survey was distributed to all active practicing orthodontists in the United States. Results. Statistically significant changes in dental and dentoalveolar arch width measured at the WALA Ridge were found in the preformed archwire group at all points of measurement except the cuspid dental measurement when compared with the control. The WALA Ridge customized archwire group had statistically non-significant changes in dental and dentoalveolar arch width at all points of measurement compared with the control. Net treatment changes when compared between the two experimental groups showed statistically non-significant differences in dental arch width changes at all points of measurement. However, statistically significant differences in changes to the dentoalveolar arch width when measured at the WALA Ridge existed at all points of evaluation. In addition, 66% orthodontists use preformed archwires in their clinical practice. Conclusions. The WALA Ridge is a stable landmark when subjected to orthodontic treatment when customized archwires shaped to the WALA Ridge are used. Changes to the WALA Ridge result with the use of preformed archwires where greater changes in pretreatment archform result. The orthodontic profession within the United States is divided between the use of preformed and customized archwires, and what to shape customized archwires to.