Clinical Performance of a New Esthetic, Self-ligating Orthodontic Bracket

A cohort of 15 patients starting orthodontic treatment with fixed appliances will receive EXD-952 Ceramic Self-ligating brackets on all mandibular incisors and a different type of brackets on the remaining mandibular teeth. Tooth movement will be initiated using 0.014" or 0.016" Nickel-Titanium archwires. A second cohort of 15 patients will receive EXD-952 Ceramic Self-ligating bracket on all mandibular incisors in a later phase of their ongoing orthodontic treatment. The mandibular incisor brackets will be removed and EXD-952 Ceramic Self-ligating brackets placed instead. Other mandibular brackets will remain in place. Tooth movement will be performed using 0.019x0.025" Stainless Steel archwires. In both cohorts bracket door stability, the ability of the door to hold the archwire in the bracket slot, the bracket's ability to rotate teeth, clinicians' satisfaction with the bracket, and patient comfort in comparison with other brackets will be assessed. The evaluation for each patient will last for at least until one archwire change (cohort 1) or one appointment interval (6-8 weeks, cohort 2). After the evaluation period, EXD-952 Ceramic Self-ligating brackets will remain in place until the orthodontic treatment is completed.

The stability of the bracket door is assessed at the time of bracket placement. Each bracket has 4 doors. Outcome is reported as the percent of bracket doors across all participants that break at bracket placement. Number of total broken bracket doors/number of total bracket doors across all participants * 100. Unit of measure is "percentage of bracket doors."

The ability of door to hold the archwire in the bracket slot is assessed at the time of bracket placement. If the door is unable to hold the archwire, then spontaneous door opening occurs. Each bracket has 4 doors. Outcome is reported as the percent of bracket doors that successfully held the archwire within the bracket slot at bracket placement. Number of successful bracket doors/number of total bracket doors across all participants * 100. Unit of measure is "percentage of bracket doors."

The bracket's ability to rotate teeth will be assessed after the first archwire change (expected 6-8 weeks after initial bonding). Clinician will rate rotational correction as adequate or not adequate. Outcome is reported as the percent of participants for whom the clinician rated rotational correction as adequate.

The clinician's satisfaction with the bracket will be assessed after the first archwire change (expected 6-8 weeks after initial bonding). Clinician will rate their satisfaction on a 5-point Likert scale (Very unsatisfied, somewhat unsatisfied, neutral, somewhat satisfied, very satisfied). A rating of 4 (somewhat satisfied) or 5 (very satisfied) is considered successful. Outcome is reported as the percent of participants for whom the clinician rated bracket satisfaction as somewhat satisfied or very satisfied.

The patient's comfort in comparison with other brackets will be assessed after the first archwire change (expected 6-8 weeks after initial bonding). Patients will rate their satisfaction on a 5-point Likert scale (Very unsatisfied, somewhat unsatisfied, neutral, somewhat satisfied, very satisfied). A rating of 4 (somewhat satisfied) or 5 (very satisfied) is considered successful. Outcome is reported as the percent of participants who rated their comfort in comparison with other brackets as somewhat satisfied or very satisfied.

Inclusion Criteria: Permanent mandibular dentition including incisors, canines, premolars, and first molars (includes subjects treated with the extraction of premolars) Mandibular incisors with sound, non-carious buccal enamel and no pretreatment with chemical agents such as hydrogen peroxide Exclusion Criteria: Mental/emotional/developmental disability Inability to give informed consent Cleft lip and/or palate, craniofacial anomaly, or syndrome Obvious oral hygiene issues such as excessive plaque accumulation, gingivitis, and/or pre-existing white spot lesions Prosthodontic or restored substrate extending on the labial surface of mandibular incisors Deep bite Known allergies to any study materials