Comparing MOP, Prostaglandin E1, and Calcitriol to Accelerate Orthodontic Tooth Movement (acceleration)

Arm A - MOP (surgical) patients receiving orthodontic treatment using a straight wire appliance with MBT prescription brackets and a 0.022-inch slot

• Anatomical target: labial cortical plate of mandibular anterior segment spanning canine to canine. Procedure: On the bonding day of the fixed appliance, self-drilling mini-implants (1.6 mm in diameter and 6 mm in length) were used to perform the MI-MOPs procedure in MOP (surgical) intervention group. Labial transmucosal MI-MOPs will be performed between the mandibular canine and lateral incisor bilaterally and between the central incisors. Two MI-MOPs at each site were performed, 2 mm and 4 mm below the alveolar bone crest. The perforation depth was decided by adding gingival tissue depth (measured by transgingival probing using Periodontal probe) plus buccal cortical bone depth (using coronal and sagittal sections of CBCT) at the level of planned perforation sites, procedure of MOP will be conducted at Day 1, , two months, 4 months.

Micro-osteoperforation is a minimally invasive surgical technique designed to capture the therapeutic advantages of the Regional Acceleratory Phenomenon (RAP). First defined in bone healing, the RAP is a protective physiological mechanism where local tissue tolerance to structural injury triggers a transient, localized burst of tissue remodeling.

By creating small, superficial pinhole perforations directly through the cortical plate of the alveolar bone into the spongy marrow spaces-without raising a full-thickness mucoperiosteal flap-MOP induces a highly localized state of controlled surgical trauma (Bolat, 2019; Farag et al., 2021). This injury provokes an immediate surge in pro-inflammatory cytokines (IL-1$\beta$, TNF-$\alpha$, and IL-6), leading to an elevated RANKL/OPG ratio.

patients receiving orthodontic treatment using straight wire appliance with MBT prescription brackets and a 0.022-inch slot size (Pinnacle®, Ortho Technology, USA).

• Dose & sites (mandibular anterior): 60 µg per visit, 10 µg (0.02mL) per site injected in to PDL at 6 sites across the mandibular anterior segment (one injection for each single tooth).
• Timing: single dose at Day 1; repeat every two weeks for 4 months. PGE1 injection will be preceded by Mental nerve block bilaterally using local anesthetic solution . The calculation of Prostaglandin E₁ dose that will be used in the current study occur according to previous clinical trials. However, in our study the target site are six mandibular anterior teeth, by multiplying dose per tooth by number of teeth, so the recommended dose will be 60 µg per visit distributed as 10 µg (0.02mL) per site. Furthermore, the normal physiological serum level for Prostaglandin E₁ 1.2-1.8 µg/mL taken in consideration

Prostaglandin analogs are synthetic compounds that mimic the effects of naturally occurring prostaglandins and are used for a wide range of clinical indications. They are used across multiple specialties, including ophthalmology, obstetrics, urology, gastroenterology, cardiology, and pulmonology.

patients receiving orthodontic treatment using straight wire appliance with MBT prescription brackets and a 0.022-inch slot size (Pinnacle®)

• Dose & sites: 60 pg per visit, 10 pg per site injected in to PDL at 6 sites across the mandibular anterior segment (one injection for each single tooth)
• Timing: single dose on Day 1; repeats every two weeks for 4 months. Calcitriol injection is preceded by Mental nerve block bilaterally using local anesthetic solution to relieve pain usually accompanied with injection techniques. In the current study, Dimethylsulfoxide (0.2 mL) (DMSO, Bisolve B.V., Netherlands) will be used for dilution with dilution factor (1:20000000) and worked as a vehicle which used in previous clinical trials The calculation of Calcitriol dose that will be used in the current study occur according to previous clinical trials and normal physiological serum level for Calcitriol is 25-66 pg/mL . So, recommended dose will be 60 pg per visit distributed as 10 pg per site

It is a biologically active form of vitamin D and plays an important role in calcium homeostasis (Reddy SR et al., 2015). A decrease in the serum calcium level stimulates secretion of PTH, which in turn increases excretion of PO4 3-, reabsorption of calcium from the kidneys, and hydroxylation of 25, hydroxycholecaliferol to 1, 25, DHCC.

patients receiving no intervention(surgical or pharmacological ) just only orthodontic treatment using a straight wire appliance with MBT prescription brackets and a 0.022-inch slot size (Pinnacle®, Ortho Technology, USA). participants receive the same standardized orthodontic mechanics, fixed orthodontic appliances (stainless steel MBT .022) were used in the current study with archwires sequence 0.014 NiTi 0.018 NiTi 0.017*0.025 NiTi 0.019*0.025 NiTi 0.019*0.025 SS (Ortho Technology, USA) (Al-Attar et al.,2022; Noori et al., 2025) Archwire will be replaced when expected improvement was achieved and next archwire could be inserted with minimal deflection.

To compare the difference in the amount of tooth movement of the mandibular anterior segment in term of Little Irrigularity Index (LII) after 6 months from the start of treatment among four arms: MOP, local PGE₁ injection, local calcitriol injection, and control.

To compare the levels of Receptor Activator of Nuclear Factor Kappa-B Ligand (RANKL), Osteoprotegerin (OPG), Interleukin-1beta (IL-1β) biomarkers in gingival crevicular fluid (GCF)

To compare the amount of orthodontically-induced inflammatory root resorption (OIIRR) in the apical region of mandibular anterior teeth

To compare the amount of pain perception during the 1st week after each archwire placement among the two pharmacological agents, microosteoperforation and control groups.