This randomized clinical trial aims to investigate the effects of locally administered vitamins C and E on mandibular incisor crowding relief during the initial stage of orthodontic treatment. The study follows a multicenter, prospective, single-blinded, parallel-group design with equal randomization (1:1) and is conducted in private clinics and hospitals.
Study Rationale
Orthodontic tooth movement involves a complex biological process mediated by bone remodeling, which is regulated by mechanical forces and biochemical mediators. Oxidative stress and inflammatory responses play a significant role in the remodeling process. Vitamin C (ascorbic acid) and vitamin E (tocopherol) are known for their antioxidant properties and potential effects on bone metabolism, tissue healing, and inflammation modulation. This study aims to determine whether locally administered vitamins C and E can enhance orthodontic tooth movement, reduce adverse effects such as root resorption, and improve patient experience during treatment.
Study Objectives
The primary objective is to compare the effectiveness of vitamin C and vitamin E injections versus a saline control in mandibular incisor crowding relief over 24 weeks.
The secondary objectives include:
* Assessing the extent of apical root resorption using periapical radiographs.
* Evaluating pain perception using a Visual Analog Scale (VAS) during the first week after each archwire change.
* Measuring patient perception of treatment experience through a structured questionnaire.
* Analyzing levels of biomarkers associated with bone remodeling (RANKL, OPG, RUNX2) in gingival crevicular fluid (GCF) to determine the biological effects of the interventions.
Participant Selection
Eligible participants are patients aged 12 years and older with moderate to severe mandibular anterior crowding (Little's Irregularity Index \[LII\] of 4-9 mm). Exclusion criteria include systemic diseases, prior orthodontic treatment, or the use of medications that could influence bone metabolism or inflammatory responses.
Intervention Groups
Participants will be randomly assigned to one of three groups:
1. Control Group: Receives saline injection.
2. Vitamin C Group: Receives intraepidermal injection of vitamin C (120 mg in 1.2 ml, divided among six mandibular anterior teeth).
3. Vitamin E Group: Receives intraepidermal injection of vitamin E (60 mg in 0.4 ml, divided among six mandibular anterior teeth).
Injections are repeated biweekly for a total of six months (24 weeks).
Orthodontic Treatment Protocol
All participants undergo standardized orthodontic treatment using MBT brackets (0.022-inch slot). The leveling and alignment phase follows a sequential archwire progression with heat-activated nickel-titanium (HANT) archwires in the following sequence:
* 0.014-inch HANT (initial 4 weeks)
* 0.016-inch HANT (weeks 4-8)
* 0.018-inch HANT (weeks 8-24)
No additional orthodontic interventions, such as interproximal reduction or extractions, will be performed during the study period.
Data Collection and Outcome Assessments
Data will be collected at multiple time points throughout the study:
1. Mandibular Incisor Crowding Relief
* 3D-scanned digital models will be used to measure Little's Irregularity Index (LII) at baseline and every 4 weeks until week 24.
2. Root Resorption
* Standardized periapical radiographs of mandibular anterior teeth will be taken at baseline, 8 weeks, and 24 weeks to evaluate root resorption.
3. Pain Perception
* Participants will record pain intensity on a VAS scale (0-10) during the first week after each wire change (every 4 weeks).
4. Patient Perception
* A structured questionnaire assessing comfort, esthetics, and perceived treatment progress will be administered at 8 weeks.
5. Biomarker Analysis
* Gingival crevicular fluid (GCF) samples will be collected at baseline, 1 week, and 4 weeks. Levels of RANKL, OPG, and RUNX2 will be analyzed to assess changes in bone remodeling activity.
Statistical Analysis
Data will be analyzed using SPSS v26.Statistical methods include:
* Descriptive statistics (mean, standard deviation, frequency).
* Reliability analysis for measurement consistency.
* Inferential statistics, including paired and independent t-tests, analysis of variance (ANOVA), and regression models, to compare treatment effects.
A significance level of 0.05 will be used for hypothesis testing.
Study Oversight and Ethical Considerations
The study is self-funded and complies with ethical guidelines for human research. Ethical approval is pending from the appropriate review board. All participants (or their legal guardians) will provide informed consent before enrollment.
Potential Impact
This trial may provide valuable insights into the role of antioxidant therapy in orthodontic treatment. If vitamins C and E positively influence tooth movement and root integrity, their use could enhance treatment efficiency while minimizing complications. Findings may also contribute to a better understanding of bone remodeling mechanisms in response to mechanical forces.