1. What data in particular will be shared?
   Response - Individual participant data that underlie the results reported in this article, after de-identification (text, tables, figures, and appendices).
   


2. What additional supporting information will be shared?
   Response -  Study Protocol
   Response -  Statistical Analysis Plan
   Response - Clinical Study Report
   
   
3. Who will be able to view these files?
   Response - Anyone
   


4. For what types of analyses will this data be available?
   Response - Any purpose.
   


5. By what mechanism will data be made available?
   Response (Others) - 


6. For how long will this data be available start date provided 01-10-2021 and end date provided 01-01-2022?
   Response - Immediately following publication. No end date.
   


7. Any URL or additional information regarding plan/policy for sharing IPD? 
   Additional Information - nil

Orthodontic treatment goal is to improve the patient’s life through enhancement of dentofacial functions and esthetics. The treatment duration is an issue of importance, for the orthodontists and the patients, particularly in adults.¹. The demand for speedy, effective and accurate orthodontic treatment systems has increased the need for shorter treatment period. Long orthodontic treatment time poses several limitations like patient burn out, gingivitis, extra hygiene appointments and dental caries. Most of the conventional orthodontic treatments require about two years for completion.² The search for mechanical orthodontic properties that cause faster and safer tooth movement has been underway with a number of studies on different components like brackets, arch-wires, orthodontic forces, tissue & cellular factors etc. It has been postulated that tooth movement is not only accelerated by the mechanical force but also by the use of pharmaceutical, electromagnetic, laser and surgical stimuli which increases rate of orthodontic tooth movement. Over the years, several surgical techniques have been developed to reduce the overall treatment time.³

                           Corticotomy facilitated tooth movement was first described by L.C. Bryan in 1893.Corticotomy or decortication simply refers to the intentional cutting of cortical bone. Periodontists began using a corticotomy technique to increase the rate of tooth movement. In 1959, Henrich Kole was the first to describe corticotomy assisted orthodontics. Kole believed that it was the thickness of the denser layer of cortical bone that offered the most resistance to tooth movement. Corticotomy acceleration of tooth movement has been reported for several types of tooth movements, including canine retraction, anterior teeth retraction, decrowding, extrusion of impacted canine and third molar uprighting. Although corticotomy procedures are quite effective in assisting acceleration of orthodontic tooth movement, they are inherently invasive because of the requirement for significant flap elevations, which potentially result in postsurgical discomfort and complications that deter patients from undergoing such procedures.⁴

                           In 1980s, Harold Frost postulated the Rapid Acceleratory Phenomenon (RAP). RAP involves the recruitment of osteoclasts and osteoblasts to the injured site, which leads to a transient localized demineralization-remineralization phenomenon in the bony alveolar housing. Dr. Thomas Wilcko (Periodontist) and William Wilcko (Orthodontist), in 1995 further modified the corticotomy with the addition of alveolar augmentation and named the procedure as Periodontally Accelerated Osteogenic Orthodontics (PAOO) later patented as “Wilckodontics”. Wilcko et al mentioned that corticotomy would increase tooth movement by increasing bone turn over and decreasing bone density.

                               An alternative approach has been introduced by Park et al followed by Kim et al,  the corticision.The technique is a minimally invasive alternative to the creation of surgical injuries to the bone that do not involve flap reflection. Incisions are made directly through the gingiva and bone using a combination of blades and a surgical mallet. While decreasing the surgical time (no flaps or sutures, only cortical incisions), this technique did not offer the benefits of bone grafting to increase periodontal support in the areas where expansive tooth movement was desired.

                                    Vercellotti introduced piezoelectric surgery in 1988 through modifying and improving conventional ultrasound technology. Following that in 2007, Vercellotti and Podesta published their study of ‘monocortical tooth dislocation and ligament distraction’ (MTDLD) technique in which they used piezoelectric surgery to improve and simplify orthodontic therapy in adult patients. Then in 2009, Dibart et al introduced ‘piezocision’ technique as a minimally invasive surgical approach to accelerate orthodontic tooth movement and shorten treatment time.⁵ This approach combines microincisions to the buccal gingivae that allow for the use of the piezoelectric knife to decorticate the alveolar bone to initiate the regional acceleratory phenomenon. Although it is minimally invasive, it also has the advantage of allowing for hard-tissue or soft-tissue grafting via selective tunneling to correct gingival recessions or bone deficiencies in patients^{.6 ,7}

                               For retracting the anterior teeth and closing space there are two basic biomechanical strategies: frictionless (closing loop mechanics) and friction (sliding) mechanics. Accurate control of anterior teeth during space closure in sliding mechanics is core to the success of orthodontic treatment. When the line of action of force passes below the center of resistance of anterior teeth, a backward moment acts on anterior teeth, resulting in tipping and extrusion of incisors.              The stiffness of the continuous arch wire supports the tooth, keeping it from tipping uncontrollably when a force is placed on it. The tooth will tip until the wire contacts the bracket at opposite corners of the slot, stopping the tipping motion. This contact with the corners of the bracket slot appears to produce a counteracting moment that pulls the root of the tooth in the same direction as the crown moved.

                                Securing appropriate anchorage is an imperative factor for achieving the objectives of orthodontic treatment. Anchorage loss often produces unsatisfactory treatment results, particularly in patients who require maximum anchorage, with a resultant increase in the treatment period. Skeletal anchorage has evolved as a mainstream orthodontic technique with the introduction of temporary anchorage devices. These devices give the clinician an alternative anchorage system instead of conventional extraoral appliances that require full patient compliance. Titanium screws have been used as skeletal anchors because they can provide absolute anchorage without patient cooperation and are useful for various orthodontic tooth movements with minimal anatomic limitations and simpler placement techniques. Orthodontic treatment combined with corticotomy and placement of a temporary anchorage device might have the advantage of shortening the orthodontic treatment period, especially in maximum anchorage situations.

                        However, there is little literature regarding the effects of piezocision. Therefore, the purpose of this study was to assess and compare miniscrew implant-supported en masse retraction with and without piezocision and also to assess the amount of anchorage loss.