Comparison of Alignment Efficiency, Arch Dimensional Changes, and Passive Extraction Space Closure Between Self-Ligating and Conventional Brackets (SLBs CBs RCT)

Saidu College of Dentistry

Status: Completed

Conditions: Passive Extraction Space; Intermolar Width; Dental Crowding; Intercanine Width

Treatments: Device: Self-Ligating Brackets (SLB); Device: Conventional Bracket

Study type: Interventional

Funder types: Other

Identifiers

NCT07503314

UHS-ORTHO-2026-01 (Other Identifier)

Details and patient eligibility

About

Purpose:

This study aims to compare two types of orthodontic braces - self-ligating brackets (SLBs) and conventional brackets (CBs) - to see which one aligns teeth faster, affects the width of the dental arch, and closes spaces after premolar extractions more efficiently.

Who Can Join:

Ages 13-30 years Moderate to severe dental crowding Skeletal Class I or mild to moderate Class II malocclusions Good oral hygiene Requiring extraction of premolars

What Participants Will Do:

Participants are randomly assigned to either the SLB group or the CB group. Braces are bonded to the teeth following standard orthodontic procedures. Dental impressions and measurements will be taken at baseline, 3, 6, and 9 months.

No extra devices (like power chains) will be used for space closure during the study.

What is Being Measured:

Alignment of teeth using Little's Irregularity Index Intercanine and intermolar widths (arch dimensions) Passive closure of extraction spaces

Why This Study is Being Done:

The study investigates whether SLBs provide any clinical advantage over conventional braces in terms of faster alignment, arch width changes, and efficient space closure in extraction cases. This could help orthodontists make evidence-based decisions when choosing braces.

Study Duration:

Total observation period: 9 months Monthly follow-ups for adjustments and measurements

Full description

This prospective, randomized controlled trial was conducted to evaluate the clinical effects of self-ligating brackets (SLBs) versus conventional brackets (CBs) in patients requiring premolar extractions. The study included 70 participants aged 13-30 years with moderate to severe crowding and skeletal Class I or mild-to-moderate Class II malocclusions.

Participants were randomly assigned to either the SLB or CB group (35 participants each) using computer-generated random numbers and allocation concealment through sequentially numbered, opaque, sealed envelopes. Blinding of the operator and participants was not possible due to the nature of the interventions; however, outcome assessors were blinded by covering brackets on dental casts with beading wax.

The study assessed alignment efficiency, arch dimensional changes, and passive extraction space closure over a 9-month period. Dental impressions and study casts were collected at baseline, 3, 6, and 9 months. Alignment was quantified using Little's Irregularity Index, while intercanine and intermolar widths and passive extraction space closure were measured using digital calipers. No active space-closing auxiliaries, such as power chains or springs, were used during the observation period.

All treatments were performed by trained orthodontic residents with calibration to ensure consistency in bonding procedures, archwire sequence, and ligation methods. Linear mixed-effects models with repeated measures and covariates (age, gender, and malocclusion type) were used for statistical analysis, and regression coefficients with 95% confidence intervals were reported.

The trial aims to determine whether SLBs differ from conventional brackets in terms of alignment speed, arch dimensional changes, and passive space closure in extraction cases. Findings from this study can inform evidence-based bracket selection and clinical decision-making in orthodontic practice.

Enrollment: 70 patients

Sex: All

Ages: 13 to 30 years old

Volunteers: Accepts Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria Age 13-30 years, any gender Moderate (4-8 mm) or severe (>8 mm) dental crowding Skeletal Class I (ANB 0-20) or mild-to-moderate Class II (ANB 3-50) Normal or vertical growth pattern (FMA 22-280) Good oral hygiene (plaque index ≤1) Require extraction-based orthodontic treatment

Exclusion Criteria Previous orthodontic treatment Asymmetric extractions Systemic diseases or medications affecting bone metabolism Cleft lip/palate or other craniofacial anomalies Congenital absence of teeth (except third molars) Low-angle (hypodivergent) growth pattern Inability to comply with treatment/follow-up

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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70 participants in 2 patient groups

Conventional Bracket Group (CB)

Active Comparator group

Description:

Participants in this group received 0.022-inch slot conventional MBT brackets (Dentaurum, Germany) bonded to all teeth up to the second premolars. Alignment started with 0.014-inch NiTi archwires and progressed according to a standardized archwire sequence. Stainless steel lacebacks were used for early canine control, and no active space-closing auxiliaries (e.g., power chains or closed-coil springs) were applied during the 9-month observation period. Outcome measurements were taken at baseline, 3, 6, and 9 months on blinded study casts.

Treatment:

Device: Self-Ligating Brackets (SLB)

Self-Ligating Bracket Group (SLB)

Experimental group

Description:

Participants in this group received 0.022-inch slot self-ligating MBT brackets (American Orthodontics, USA) bonded to all teeth up to the second premolars. Alignment started with 0.014-inch NiTi archwires and progressed using the same standardized archwire sequence. Stainless steel lacebacks were applied for early canine control, and no active space-closing auxiliaries were used during the 9-month observation period. Outcome measurements were taken at baseline, 3, 6, and 9 months on blinded study casts.

Treatment:

Device: Conventional Bracket