Comparing scalloped, straight, and straight-extended trimlines for SureSmile clear aligners

A Prospective, Multicenter, Randomized, Post-market Clinical Investigation to Assess the Accuracy of Different Tooth Movements for Patients Undergoing Clear Aligner Therapy (CAT) With SureSmile® Clear Aligners With Three Different Trimlines.

This study tests whether three different trimline designs for SureSmile clear aligners give accurate tooth movements in adults with mild-to-moderate malocclusion.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 90 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Dentsply Sirona Implants and Consumables (Industry-sponsored)
• Locations: 6 sites (Fresno, California and 5 other locations)
• Trial ID: NCT07290790 on ClinicalTrials.gov

What this trial studies

This prospective, multicenter clinical investigation enrolls adults with permanent dentition and mild-to-moderate malocclusion (Levels 1–2) and assigns them to one of three treatment arms using SureSmile clear aligners with scalloped, straight, or straight-extended trimlines. The primary objectives are to confirm device safety and measure the accuracy of planned versus achieved tooth movements for different trimline designs. Participants will receive the assigned aligner treatment and attend scheduled follow-ups at one of three U.S. centers where clinicians will document outcomes using clinical exams and digital scans. Results will compare movement accuracy metrics and any adverse events across the three trimline groups.

Who should consider this trial

Good fit: Adults (18+) with permanent dentition and mild-to-moderate malocclusion consistent with Levels 1–2 case complexity (for example, crowding/spacing ≤6 mm, midline deviation ≤3 mm, overjet ≤4 mm, overbite ≤3 mm) are ideal candidates.

Not a fit: Patients with severe malocclusion beyond Levels 1–2, missing second molars or not in permanent dentition, significant open bites beyond the protocol limits, or those under 18 are unlikely to benefit from this investigation.

Why it matters

Potential benefit: If successful, the results could help clinicians choose a trimline design that produces more predictable tooth movements and reduces the need for corrective adjustments.

How similar studies have performed: While clear aligner systems including SureSmile have evidence supporting predictable movements in selected cases, direct head-to-head comparisons of these specific trimline designs are limited, so this comparison is relatively novel.

Eligibility criteria

Inclusion Criteria:

* Subject willing to participate in the clinical investigation, able to understand the intent risks and benefits of the clinical investigation as well as associated time commitment and follow-ups visits.
* Subject has signed and dated the informed consent form (ICF) .
* Subject aged 18 years or above at time of informed consent.
* Subject has permanent dentition (i.e., all 2nd molars).
* Subject with a dental malocclusion, consistent with Levels 1 and 2 case complexity and within the clinical references as defined in the SureSmile Case Selection Guide.

  * Crowding or spacing must be ≤6mm present in one or both arches consistent with level 1 and 2 of case complexity.
  * Midline deviation must be ≤3 mm consistent with level 1 and 2 of case complexity.
  * Overjet must be ≤4 mm consistent with level 1 and 2 case complexity.
  * Overbite must be ≤3 mm consistent with level 1 and 2 case complexity.
  * Anterior open bite must be ≤1 mm, consistent with level 1 and 2 case complexity.
* Intermaxillary elastics may be included within the treatment plan to support sagittal, vertical, or transverse correction within the limits defined under exclusion criteria.

Exclusion Criteria:

* Subjects unlikely to comply with investigational procedures, or unlikely to come back for follow-up visits, as judged by the Investigator.
* Subject that presents a dental malocclusion classified as level 3 case complexity, as defined in the SureSmile Case Selection Guide.
* Subjects who have completed aligner therapy within the last 12 months or who are in active orthodontic treatment.
* Subjects with active periodontal disease or other unresolved dental conditions such as active cavities, active periodontal disease.
* Subjects with treatment plans requiring transverse correction requiring expansion greater than 4 mm per arch or 2 mm per quadrant, or any skeletal transverse correction.
* Treatment plans requiring sagittal correction exceeding a half-cusp discrepancy (i.e., \>½ unit) in molar or canine relationships.
* Subjects with treatment plans require vertical correction beyond Level 1 and 2 thresholds (i.e., overbite \>3 mm or anterior/posterior open bite \>1 mm), or vertical elastics exceeding 3 mm.
* TMJ (Temporo-Mandibular Join) disorders or history of headaches or migraines.
* Participants with known history of plastic allergies.
* Subjects with presence of skeletal discrepancies necessitating orthognathic surgery, rapid palatal expansion, other orthopedic intervention, unilateral or bilateral cross-bites, mandibular deviations in association with the diagnosed malocclusion
* The use of TADs (Temporary Anchor Devices), plates, other fixed anchorage ancillaries or the use of functional appliances (distalizers, growth modification devices), any approach involving orthopedic or skeletal sagittal correction or the use of hybrid fixed appliances are not considered part of the scope of this clinical investigation and these subjects are not eligible.
* Uncontrolled para-functional habits, e.g., bruxism.
* Any other condition that would make the subject unsuitable for participation, including but not limited to:

  * Unstable psychiatric illness.
  * Recent myocardial infarction (\< 3 months\*).
  * Recent cerebrovascular accident (\< 3 months\*).
  * Recent cardiac-valvular prosthesis placement (\< 3 months\*).
  * Hemorrhagic diathesis.
  * Severe liver dysfunction.
  * Known or suspected current malignancy.
* Known pregnancy at the time of enrolment.
* Previous enrolment in the present clinical investigation.
* Involvement in the planning and conduct of the clinical investigation (applies to both Dentsply Sirona personnel and the clinical investigation site).
* Participation in another clinical investigation that may interfere with the present clinical investigation.

Where this trial is running

Fresno, California and 5 other locations

• Costanzo Orthodontics — Fresno, California, United States (Recruiting)
• Center for Orthodontic Excellence — Princeton Junction, New Jersey, United States (Not_yet_recruiting)
• J Chichetti PLLC 2 — Huntersville, North Carolina, United States (Recruiting)
• Brush 365 Dental — Frisco, Texas, United States (Recruiting)
• Clinica Dental Ortiz Puigpelat — Barcelona, Spain (Not_yet_recruiting)
• The Sanford — Bexleyheath, United Kingdom (Not_yet_recruiting)

Study contacts

• Study coordinator: Freja Freedman

Conditions Malocclusion