Orthodontic treatment (OT) is characterized as a lengthy procedure and enormous effort has been harnessed to shorten the OT duration using either surgical or non-surgical approaches. With the emerging concept of "accelerated orthodontics," scientific interest has been focused on chemical and electrical stimuli in combination with mechanical forces for rapid bone turnover and more stable results. Given the role of cytokines, parathyroid hormone, active vitamin D3 (1,25 dihydroxycholecalciferol) in bone regeneration, several studies have been conducted in which exogenous biological molecules have been locally administrated in order to stimulate orthodontic tooth movement.

Vitamin D (Vit-D) plays a significant role in bone biology and remodeling.There are two primary forms of Vit-D: 25-OHD (25-hydroxyvitamin D) and 1,25 DHC (1,25-dihydroxycholecalciferol) which is the active form.

1,25 DHC is a potent stimulator of osteoclastic activity by inducing differentiation as well as increasing the activity of osteoclasts. It is also known to work in a dose-dependent way. Although it has a 2-3-hour plasma half-life, its effects on cells might last for days. Injecting the active form of Vitamin D can increase tooth movement, decrease the treatment time of fixed appliances and maintain the integrity of the bone.

In the past researches have been done on cats and rodents on the effect of intraligamentary administration of vitamin D3 on tooth movement. Studies performed on human beings are few and inconclusive. Two out of the four studies done on humans were cross-sectional and investigated the role of active vitamin D on external apical root resorption. The other two clinical trials used split-mouth technique and examined the impact of local CTL administration on tooth movement rate, both demonstrating level 1 of evidence and high recommendation. Al-Hasani and colleagues reported that a low dose of 25 picogram/mL produced a higher rate of OTM, with no statistically significant difference between the study and control sides in 15 patients involved in the study. However, Iosub Ciur and colleagues reported 70% acceleration in the OTM when using higher 42 picogram/mL local dose of vit D, but the number of patients was extremely low and not adequate(n=4) in this study. The purpose of our study is to evaluate if higher doses of local vitamin D can accelerate tooth movement in adequate number of adult patients. If vitamin D in our population of adult patients can accelerate tooth movement, then it can allow for more predictable treatment outcome during fixed orthodontic therapy.

The main purpose of this study is to see if we can accelerate canine retraction by injecting Vit D in the distal side of canine after extraction of premolar.

30 patients will be taken for this study matching the inclusion criteria and their maxillary arch will be divided into two sides: study side and control side by computer generated randomisation as it is a split mouth randomised control trial. After bilateral extractions of maxillary premolars, the study side will be injected with vitamin D (active form 1,25 DHC) in a solution of DMSO and the control side will be injected with plain DMSO (placebo) at three time points T1( after extraction), T2 (one month after), T3 ( two months after). Canine retraction in the extraction space will be measured by taking impressions at each timepoint and measuring the distance on study casts.

Inclusion Criteria:

• Patient with permanent dentition
• Angles class 1,class II dental malocclusion, indicated for bilateral maxillary first premolar extraction
• minimum 5 of extraction space

Exclusion Criteria:

• several craniofacial deformities such as cleft lip and palate
• history of bone disease such as osteoporosis or diabetes
• pregnant and lactating women

individual patient proformas will be shared containing each measurement of canine tooth movement with time

15/05/2026 till forever

IPD document will be shared with the journal and will be available to all on request