Comparison of Canine Retraction Using Ni-ti Closed-coil Springs Vs Elastomeric Power Chains During Orthodontic Treatment

The objective of this study is to compare the canine retraction rate (in mm with a 100 mm marked scale) using Ni-Ti closed-coil springs versus elastomeric power chains during canine retraction in subjects with first premolar extractions over a period of three months.

After the extraction of all first premolars under local anesthesia. For canine retraction, Ni-Ti closed-coil springs and elastomeric power chains will be randomly allocated to the right and left quadrants of both arches.

Radiographic measurement (root resorption) and clinical measurements (canine retraction, plaque accumulation and gingival health) will be recorded at four points in time. First, at the start of the canine retraction (T0), after first month (T1), second month (T2) and third month follow-up (T3).

RATIONALE:

Premolar extraction followed by canine retraction is one of the common practices in orthodontics to treat malocclusion such as severe crowding and proclination of anterior teeth. It is essential to know methods and techniques that result in minimum or no adverse effects on roots of teeth and periodontal health. This will help the clinicians to choose the best method that will result in a faster and more physiological closure of extraction spaces. Moreover, to the best of our knowledge, limited studies have compared the effects of Ni-Ti closed-coil springs and elastomeric power chains on canine root resorption, gingival health and plaque accumulation. It is necessary to establish a comparison between these methods, as it can help clinicians to provide better care and enhance the overall effectiveness of orthodontic treatment.

OBJECTIVE:

Primary Objective: The objective of this study is to compare the canine retraction rate (in mm with a 100 mm marked scale) using Ni-Ti closed-coil springs versus elastomeric power chains during canine retraction in subjects with first premolar extractions over a period of three months.

Secondary Objective: This study will also include an assessment of canine root resorption (in mm using periapical radiograph), dental plaque accumulation and gingival health (according to indices mentioned below with CPI-TN probe) using Ni-Ti closed-coil springs versus elastomeric power chains during canine retraction in subjects with first premolar extractions over a period of three months.

HYPOTHESIS:

Null Hypothesis: There is no significant difference between Ni-Ti closed-coil spring and elastomeric power chain on the canine root resorption, retraction rate, dental plaque accumulation and gingival health in subjects with first premolar extractions.

Alternate Hypothesis: There is a significant difference between Ni-Ti closed-coil spring and elastomeric power chain on the canine root resorption, retraction rate, dental plaque accumulation and gingival health in subjects with first premolar extractions.

DATA COLLECTION PROCEDURE:

After obtaining an approval from the Ethical Review Committee and taking informed consent and informed assent from the parents and child respectively, these patients will be recruited in the study as participants. Patients visiting the orthodontic clinic at the Aga Khan University Hospital Karachi will be included in this study. Detailed information regarding the study will be provided to the participants and they will be given the choice to either accept or refuse their inclusion in the study. After the extraction of all first premolars under local anesthesia, 0.018" stainless steel archwires will be inserted in the maxillary and mandibular arches. For canine retraction, Ni-Ti closed-coil springs and elastomeric power chains will be randomly allocated to the right and left quadrants of both arches. Radiographic measurement (root resorption) and clinical measurements (canine retraction, plaque accumulation and gingival health) will be recorded at four points in time. First, at the start of the canine retraction (T0), after first month (T1), second month (T2) and third month follow-up (T3). Canine retraction rate will be recorded by using a 100 mm marked scale. Data will be collected on an organized study proforma

Eligibility Criteria:
Inclusion Criteria:

* Patients aged between 13 - 40 years
* Patients undergoing fixed orthodontic treatment
* Patients requiring all first premolars extraction as part of orthodontic treatment
* Patients with all permanent teeth present and erupted (except for second and third molars)
* All patients who will sign the informed consent/assent form

Exclusion Criteria:

* • Patients with systemic diseases that can affect tooth movements

  * Patients with uncontrolled periodontal disease
  * Patients with craniofacial syndromes
  * Pregnant or lactating mothers
  * Patients with bracket failures greater than three times per bracket during the study
  * Patients on medications that can affect tooth movements
  * Patients with Nickel allergy