To study the effect vitamin D effect on orthodontic tooth movement when used in combination with coticision technique, independent t test or an equivalent non-parametric test will be used for comparison. According to a previous study by (S. T. Varughese, et al. (2019) , "Effect of vitamin D on canine distalization and alveolar bone density using multi-slice spiral CT: a randomized controlled trial

Assessment of the locally administrated vitamin D3 and corticision efficacy on orthodontic canine retraction: A prospective clinical study

Protocol submitted in partial fulfillment of the requirements for the Master Degree in dental science in Orthodontics By Mahmoud Elsaid Elsayed Ahmed BDS 2017, Faculty of Dental Medicine, Boys, Cairo Al-Azhar University Dentist at armed forces hospitals Supervisors

Department of Orthodontics Faculty of Dental Medicine (Boys-Cairo) Al-Azhar University 2024G - 1446H

1. Introduction Accelerating the rate of tooth movement is desirable to patients because it shortens treatment time and also to orthodontists because treatment duration has been linked to an increased risk of gingival inflammation, decalcification, dental caries, and root resorption.

   The average duration of comprehensive orthodontic treatment is less than 2 years with a mean of 19.9 months. But sometimes, prolonged periods of wearing oral braces, particularly non cosmetic appliances, tend to keep patients, especially adults, away from seeking treatment, even when it is clearly indicated. Moreover, longer treatment durations are expensive for both the patient and the orthodontist. Therefore, one of the best ways to overcome this problem is to speed up the velocity of tooth movement from its usual rate of 0.8-1.2 mm/month (when continuous forces are applied).

   There are different approaches of acceleration of orthodontic tooth movement; biomechanical, physiological, mechanical, Pharmacological, surgical assisted and surgery simulated approaches .

   Pharmacological approaches to accelerate orthodontic tooth movement include local cytokine delivery, prostaglandins application, receptor activator of nuclear factor kappa-B ligand (RANKL), parathyroid hormone, vitamin D3 and corticosteroids.

   While physical stimuli to accelerate orthodontic tooth movement include direct electric currents and pulsed electromagnetic fields, vibratory stimuli and photobiomodulation . Both pharmacological and physical approaches are considered non-invasive techniques to accelerate orthodontic tooth movement.

   Surgical maneuvers to accelerate orthodontic treatment were first described in late 1950, when corticotomy was performed as cortical bone was identified the main tissue layer to resist tooth movement. Corticotomies were found to cause no damage to the pulpal tissues blood supply or periodontal tissues vitality.

   The minimal invasive surgical techniques include piezocision and corticision. The piezocision which has successfully been used in correction of class III malocclusion, achieved with a treatment time of 8 months, and a follow up at 15 months.

   Another minimally-invasive surgical technique is cortisicion which has been proposed by Young Guk Park (2006) and experimented on cats (2009) . A reinforced scalpel was used as a thin chisel to separate the interproximal cortices transmucosally without flap reflection. Histologic analysis at day 14 revealed large resorption cavities filled with osteoclasts, which accelerated tooth movement, and the healing process was initiated at this site by day 21, suggesting a catabolic remodeling of bone with this procedure .

   Prostaglandins (PGs) are inflammatory mediator that acts on nearby cells; they stimulates bone resorption by increasing directly the number of osteoclasts. In vivo and in vitro experiments were conducted to show clearly the relation between PGs, applied forces, and the acceleration of tooth movement.

   1,25 dihydroxycholecalciferol (vitamin D3) is the most active hormonal form of vitamin D. It regulates calcium and phosphate serum levels by promoting their intestinal absorption and reabsorption in the kidneys. Furthermore, it promotes bone deposition and inhibits PTH release. It also plays a role in the immune response by promoting immunosuppression. 1,25(OH)2D3 deficiency can result from inadequate intake combined with inadequate sunlight exposure, eventually leading to impaired bone mineralization, rickets, and osteoporosis. Furthermore, it can lead to increased susceptibility to high blood pressure, periodontal disease, affective disorders, and auto-immune diseases. Therapy for 1,25(OH)2D3 deficiency involves diet changes or taking 1,25(OH)2D3 as a supplement. Hypervitaminosis D causes hypocalcemia and might cause anorexia, nausea, polyuria, and eventually renal failure. It can be treated with a low-calcium diet and corticosteroids. The effect of 1,25(OH)2D3 on OTM has been studied in rats by several authors.

   In 1 investigation, injections with 2.10-9 or 2.10-7 mol 1,25(OH)2D3 were given every third day in the submucosal palatal area of the root bifurcation of first molars, and the molars were subsequently moved buccally with forces of 5 to 20 cN.

   In another study, 2.10-9 mol 1,25(OH)2D3 was injected every third day adjacent to the incisors, which were subsequently moved distally with forces of 20 cN. Both studies showed that 1,25(OH)2D3 stimulated the rate of OTM in a dose-dependent manner. A similar effect was found for canine retraction in cats after local administration of 1,25(OH)2D3 in dosages as low as 0.25 * 10-13 mol and an applied force of 60 cN.Physiologic doses of 1,25(OH)2D3 do not stimulate bone resorption; conversely, low supplemental administration does, possibly by upregulation of RANKL (receptor activator for nuclear factor kB ligand) expression in osteoblasts, leading ultimately to osteoclast differentiation through the RANK/RANKL system.

   The normal circulating level of vitamin D3 in humans is 15 pg/mL (1 pg =10-5 g). The recommended dietary allowance of vitamin D in human adults is 400 IU (10 mg)/day. Vitamin D3 is a safe drug for human beings, and it can be either injected intramuscularly or administered by local infiltration into the oral cavity.

   Shetty A, et al. use one mL of commercially available Vitamin D3 (Arachitol-6l, Solvay Pharma India Pvt Ltd, Mumbai, India) containing 15 mg of Vitamin D3 per mL of solution was dissolved in 999 mL of 2% Xylocaine containing adrenaline 1:200,000 (AstraZeneca Pharma Ltd, New Delhi, India) to prepare a stock solution having 15 mg (600 IU) of Vitamin D3 per mL of solution for local injection Distal canine movement is the core time-consuming procedure for premolar extraction patients. Conventional techniques result in canine retraction rates of 0.5 to 1 mm per month, depending on the patient's age and sex. Therefore, full canine retraction can require 5 to 9 months. Conventional treatments with fixed appliances are likely to require 1.5 to 2 years. For rapid canine retraction, Liou and Huang (1998) proposed periodontal ligament distraction. Some researchers have reported the use of dentoalveolar distraction based on the principles of distraction osteogenesis. ; others have used selective alveolar decortication and claimed that this procedure invokes transient osteopenia. Modified surgical techniques have been reported to be effective in reducing clinical orthodontic treatment times.

   The current study will be aimed to assess the locally administrated vitamin D3 and corticision efficacy on orthodontic canine retraction.

2. Aim of the study This clinical study will be directed to assess the locally administrated vitamin D3 and corticision efficacy on orthodontic canine retraction.

3. Materials and methods 3.1. Study design: A prospective randomized clinical study. 3.2. Study setting and Population: The reference population for this prospective study comprised from patients waiting for treatment at Faculty of Dental Medicine, (Boys- Cairo) AL- Azhar University. This study will be conducted on sixteen patients selected from the outpatient clinic, Orthodontic Department, Faculty of Dental Medicine (Boys), Al-Azhar University, Cairo. The number of patients will dependent on a power study.

3.3. Sample size calculation To study the effect vitamin D effect on orthodontic tooth movement when used in combination with coticision technique, independent t test or an equivalent non-parametric test will be used for comparison. According to a previous study by (S. T. Varughese, et al. (2019) , "Effect of vitamin D on canine distalization and alveolar bone density using multi-slice spiral CT: a randomized controlled trial.

Using G power statistical power Analysis program (version 3.1.9.4) for sample size determination[2], A sample size (n=12; subdivided to 6 in each group) will be sufficient to detect a large effect size (d) = 1.85, with an actual power (1-β error) of 0.8 (80%) and a significance level (α error) 0.05 (5%) The sample size will be increased to 16 patients subdivided to 8 patient in each group.

Screen shot of calculation for power (1-β error) of 0.8 (80%)

3.4. Inclusion criteria:

1. orthodontic patients referred for therapeutic extraction of bilateral maxillary first premolars (Angle Class II division 1 cases, with crowding and bimaxillary protrusion).
2. Fully Erupted permanent teeth (except third molar).
3. Age 13-20 patients.
4. No previous orthodontic treatment.
5. Good oral and general health.
6. No systemic disease or regular medication that could interfere and/or affect orthodontic teeth movement.

3.5. Exclusion criteria:

1. Patients with impacted canine.
2. Patients with severe crowding.
3. Patients with untreated decay or any endodontic lesions.
4. Patients with thyroid, parathyroid, or renal and liver disease. 3.6. Discontinuation criteria:

1- Patients not keeping on instructions for eating and tooth brushing. 2- Incompliant patients. 3- Missing many appointments. 4- Repeated appliance fracture. 5- hypersensitivity to vitamin D or its analogues/derivatives 3.7. Records:

For every patient the following records will be taken before and after canine retraction procedure:

1. Standardized Extra and intra-oral photographs.
2. Standardized panoramic radiograph.
3. lateral cephalometric radiograph.
4. Standardized orthodontic study models before starting treatment ,also before the corticision and application of vitamin D3 and and after 3 months of starting canine retraction to assess the rate of orthodontic tooth movment .
5. Cone beam computed tomography (CBCT) will be taken before the corticision and application of vitamin D3 and at the of canine retraction at any side or after 6 months of starting canine retraction to assess the amount of canine retraction and canine root resorption .

3.8. Intervention:

The total sample of patients will be randomly divided into two equal groups:

(Group A): 8 patients will receive local application of vitamin D3 combined with corticision as a minimally invasive surgical method for accelerating tooth movement.

(Group B): 8 patients will receive conventional treatment.

Administration of the Solution at eexperimental side:

One milliliter of was injected into the buccal vestibule at the level of the distal margin of the root of the canine.

One milliliter of (ONE ALPHA 2 MCG / ML 10 AMP 0.5 ML Leo Pharmaceutical products Ballerup - Denmark. Imported by: Egyptian Company for Drug Trading) was injected four times during treatment on the the beginning (T0), 4 weeks (T1), 8 weeks (T2), and 12 weeks (T3) of canine retraction on both sides according to Varughese, et al.

" Participants were evaluated from the beginning (T0), 4 weeks (T1), 8 weeks (T2), and 12 weeks (T3) of canine distalization. At these appointments, impressions were made to obtain the study models. Multi-slice spiral computed tomography scans were taken at T0 and T3 to measure the changes in bone density following canine distalization. The primary outcome was to evaluate the rate and total amount of canine distalization as well as anchorage loss in the maxillary arch. All study measurements were performed on dental casts with stable reference points using digital vernier caliper. The movement of canine was measured from the canine tip and mesiobuccal groove of maxillary first molar. Measurements were repeated to check for reproducibility. The rate of canine distalization was obtained by calculating the differences between sequential measurements (T0-T1, T1-T2, and T2-T3). The total amount of movement was the difference between T0 and T3. The mean monthly movement was obtained by dividing the total amount of movement by three (number of evaluations). The molar anchorage loss was measured from mesiobuccal groove of maxillary molar and lateral ends of third palatal rugae. The secondary outcome was to evaluate the changes in the alveolar bone density (axial section) in the maxillary arch. It was measured in the alveolar bone on the experimental and control sides at the region distal to canine root, at the beginning and the 12th week (BX) of canine distalization. The MSCT (HiSpeed NXI MultiSlice CT system GE Medical system) parameters used were 0° gantry tilt, high-resolution bone Kernel, 0.5 mm nominal slice thickness, 120 kV, and 120 mA. The measurements were calculated using Advantage Workstation software (AW-Version 4.3) in HU. The CT sections were taken 3-5 mm apical from the alveolar bone crest. At each axial section, the density at the center point12 of the buccal cortical bone (BC), cancellous bone (C), and palatal cortical bone (PC) was measured. The density of the cancellous bone was measured at the trabeculae, located halfway buccolingually between the buccal and palatal cortical plates."(33) 3.9. Observation: Each patient will be followed up on periodic base for progress evaluation and integrity checks, as well as orthodontic tooth movements will be evaluated using CBCT images and study models taken before and after the treatment.

3.10. Ethical considerations: An informed consent form (attached copy) that explains every step in the research will be given and discussed carefully with the patient and his/her parents before participation in the study and should be signed freely. The objectives of the study will be discussed and explained with the patients and / or their guardians and they will receive a copy of the consent form as well .

The proposals will submitted to ethical committee of faculty Dental Medicine (Boys- Cairo), Al-Azhar University.

3.11. Statistical analysis; Data tabulated and statistical analysis will performed using a commercially available software program (SPSS Chicago, IL, USA version 26). Numerical data will be described as mean and standard deviation or as median and range as appropriate according to the normality of the data. Mann Whitney U test or independent t test depending on normality . The level of significance will be set at P≤0.05. All tests will be two tailed.

Inclusion criteria:

1. Orthodontic patients referred for therapeutic extraction of bilateral maxillary first premolars (Angle Class II division 1 cases, with crowding and bimaxillary protrusion).
2. Fully erupted permanent teeth (except third molar).
3. Age 13-20 patients.
4. No previous orthodontic treatment.
5. Good oral and general health.
6. No systemic disease or regular medication that could interfere with and/or affect orthodontic teeth movement.

Exclusion criteria:

1. Patients with impacted canines.
2. Patients with severe crowding.
3. Patients with untreated decay or any endodontic lesions.
4. Patients with thyroid, parathyroid, or renal and liver disease.