Efficacy of Orthodontic Tooth Movement Using Beveled and Conventional Attachments in Aligners

Participant recruitment will take place after approval by the Research Ethics Committee until July 2027. The consultations will occur in a private clinic in Curitiba - PR, Brazil.

Participants will be selected and randomized according to the split-mouth study design. Teeth on each side will have different attachment configurations to aid orthodontic aligner movements. One side will use rectangular attachments, and the other side will use beveled attachments. Groups will be divided as follows:

Group H: 20 teeth/attachments with horizontal displacements (parallel to the occlusal plane) including tipping or mesio-distal translation - premolars and molars.

Group V: 20 teeth/attachments with vertical displacements (extrusion and intrusion) - incisors.

Group R: 20 teeth/attachments with mesio-distal rotations - canines and premolars.

Digital study models (intraoral scanner) will be obtained before and after treatment. These intraoral scans will be analyzed alongside the planned movement models generated by the orthodontic treatment planning software.

Treatment efficacy will be analyzed using tooth-tracking methodology in Geomagic Control X, measuring the differences between planned and achieved movements and calculating the percentage of achieved orthodontic tooth movement.

Additionally, pre- and post-treatment clinical photographs will be taken:

Intraoral:

Frontal in occlusion; Right and left lateral views in occlusion; Occlusal views of upper and lower arches.

Extraoral:

Frontal with lips at rest; Frontal with a wide smile; Profile with lips at rest. All participants will receive orthodontic aligner treatment supervised by a qualified professional capable of providing relevant care under clinical trial conditions. Diagnosis, movement planning, and therapy monitoring procedures (e.g., aligner replacement frequency) for each individual will be established by the researcher, respecting the manufacturer's specified instructions.

The sample size was 30 participants will be recruited, totaling a sample of 120 teeth/attachments.

Participant satisfaction will be recorded pre-treatment, during follow-up, and post-treatment. In this study, oral health-related quality of life will be assessed through the OHIP-14 (Oral Health Impact Profile-14) questionnaire as a measure of participant satisfaction with the treatment.

Initial and final digital models will be imported using software, where measurements will be taken to identify the magnitude and direction of movements resulting from treatment with different attachment types:

Horizontal displacements (parallel to the occlusal plane) including tipping or mesio-distal translation - premolars and molars.

Vertical displacements (extrusion and intrusion) - incisors. Mesio-distal rotations - canines and premolars.

Descriptive statistics will be calculated for each type of tooth movement evaluated and described by mean, standard deviation, median, quartiles, minimum, and maximum. Paired tests will be conducted due to the split-mouth design. Correlation tests will also be applied if necessary.

Inclusion criteria

• Adults (18+ years) with permanent dentition
• Candidates for aligner-based orthodontic treatment
• Require bilateral tooth movements (e.g., extrusion, intrusion, rotation, tipping, mesiodistal translation)
• Provide written informed consent

Exclusion criteria

• Contraindications to aligner use (e.g., manufacturer's guidelines)
• Poor oral hygiene, active periodontal disease, or TMJ disorders
• Allergies to aligner materials (e.g., polyurethane, PETG)