*3.3.1. Corticotomy and osteotomy combinations*

They were first used by Heinrich Köle who stated that the basic resistance toward tooth movement was in cortical layer so by applying corticotomies and osteotomies might accelerate tooth movement by breaking the resistance [27]. Köle et al. applied vertical corticotomies between the roots of two adjacent teeth buccally and lingually and horizontal osteotomies subapically as to combine corticotomies buccal-lingually. They theorized that the segments which became "blocks of bone" move as a whole to achieve rapid tooth movement without devitalization in long-term monitoring. Düker et al. also reported that pulpal and periodontal tissues of the teeth which were applied orthodontic force similarly were not damaged in their study on dogs with reference to Köle's corticotomies [28].

Although Köle and Düker proposed the opposite, periodontal and pulpal damages can be formed following invasive horizontal subapical osteotomies [29]. Additionally, osteotomy surgery is an invasive intervention with possible complications such as vascular and nerve damages so it is not a widely accepted method [30]. Nonetheless, Köle's studies pioneered surgery-assisted methods which accelerate tooth movement to be involved in the literature of modern orthodontics.

#### *3.3.2. Corticotomy-assisted treatments*

B (RANK), receptor activator of nuclear factor-kappa B ligand (RANKL) pathway, mitogen-

Low-dosage laser applications are reported to increase osteoblastic and osteoclastic activity by stimulating cellular proliferation and differentiation and accelerate orthodontic tooth

It is also reported that electromagnetic field applications increased levels of a group of enzyme which is responsible from regulating intracellular metabolism and cellular proliferation accordingly by influencing sodium-calcium change speed in cell membrane [21]. Increase in osteoblastic and osteoclastic activity causes an acceleration in the tooth movement. Darendeliler et al. [22] reported that static magnetic field accelerated tooth movement by shortening unproductive period when no tooth movement is observed but the side effect

Applying direct electric current is also among tooth acceleration techniques, but its clinical use is asserted as not appropriate due to some complications such as application difficulty, ionic reactions that cause damages in tissues, and replacing of bone tissue with connective tissue [23].

Resonance vibration and ultrasonic vibration are also among the methods which are used to accelerate tooth movement. Resonance vibration is reported to increase release of peptide which is called RANKL within periodontal ligament and increase tooth movement rate by providing formation, function, and continuity of osteoclasts. Tooth movement can also be accelerated via ultrasonic vibration with the same mechanism but there is a risk that the heat

The most clinically used and predictable option with stable results among the techniques which accelerate tooth movement is the surgical-assisted technique; it is evaluated as a costly invasive method [6]. It is based on the idea that rapid tooth movement can be achieved by increasing the biological response which is formed in periodontal ligament and alveolar bone. Creating an injury in the bone is a potential physical mechanism which provides rapid tissue recovery. Higher regional tissue response during this tissue remodeling/regeneration period is called as regional acceleratory phenomenon (RAP) [24]. Regional acceleratory phenomenon is a complex physiological case in which initially osteoclastic activity and secondly bone density is decreased followed by a rapid osteoblastic activity and a remodeling process. Orthodontic tooth movement acceleration is provided via the increase in cytokine activity around the teeth and decrease in cortical bone resistance and formation of hyalinization tissue by activation of this recovery mechanisms [25]. The advantages of the dentoalveolar surgical intervention in orthodontic treatment of adult patients are reported as: (a) less treatment time, (b) avoidance of potential periodontal complications, (c) favorable direction of growth, and

They were first used by Heinrich Köle who stated that the basic resistance toward tooth movement was in cortical layer so by applying corticotomies and osteotomies might accelerate

activated protein kinase (MAPK), c-fos, and nitric oxide [6, 19].

can cause damage in the dental pulp [19].

(d) extensive envelope of the tooth movement [26].

*3.3.1. Corticotomy and osteotomy combinations*

**3.3. Surgical-assisted techniques**

76 Current Approaches in Orthodontics

movement without creating side effects on periodontal ligament [6, 20].

can be a decrease in serum calcium and slight changes in the chemistry of blood.

Köle's horizontal subapical osteotomies were changed with horizontal subapical corticotomies by Gantes et al. [31] and Suya [32] and it was stated that treatment of the cases was completed in almost 50% less period when compared to conventional methods. Gantes et al. [31] reported that overall vitality of the tooth was preserved and none of the patients had a periodontal damage that can be clinically recognized despite minimal root resorptions and gingival recession. Suya [32] asserted that corticotomy-assisted orthodontics had less root resorption and relapse risk and pain when compared to traditional treatments. In a recent study, Uzuner et al. [33] reported that corticotomy-assisted orthodontics increased the rate of tooth movement during canine retraction in 20% ratio and also relative bodily movement was achieved with the corticotomy-combined treatment.

#### *3.3.3. Periodontal ligament distraction*

The method was introduced to orthodontic literature by Liou and Huang [34]. Initially, a distractor device which consists of canine and molar bands was applied to the patients by the researchers and following extraction of upper first premolar teeth, surgical preparation phase which consists of two vertical channels formed buccally and lingually toward canine teeth through the extraction socket and a horizontal incision on the base of the extraction socket that connects the channels was completed at the same session. Interseptal bone was not cut mesiodistally during the surgical intervention. Activation was carried out without a need for latent period different from traditional distraction method and distalization of canine teeth was completed in a short period of 3 weeks with minimal anchorage loss. None of the patients suffered from pain and minimal resorption was observed in the roots of canine teeth in the radiographies at the end of procedure. Suggesting to be used especially in orthodontic treatments with primary premolar extraction which has anterior crowded teeth, Liou and Huang [34] associate the periodontal ligament distraction with this method to the distraction which is formed in midpalatal suture during rapid maxillary expansion.

#### *3.3.4. Dentoalveolar distraction*

The method was introduced by Kişnişci et al. [35] in 2002. The researchers applied a distraction device before teeth extraction as in periodontal ligament distraction method but a more rigid device was used. Initially, the osteotomy curved apically at a distance of 3–5 mm from the apex of the canine at the same session with the primary premolar tooth extraction as a surgical preparation. Cortical bone which remained in the buccal of the socket after the extraction was carefully removed. Direct distraction was applied by skipping latent period similar to periodontal ligament distraction method. Canine distraction was reported to be completed within 8–12 days without anchorage loss. Root resorption or vitality loss was not observed in the posttreatment evaluations.

*3.3.6. Corticision*

*3.3.7. Piezocision*

following the procedure.

*3.3.8. Piezopuncture*

The necessity to remove flaps during corticotomy-assisted orthodontic treatment makes the method invasive, decreasing its acceptability by the patients and clinicians. Therefore, corticision was introduced by Park et al. [41] as an alternative approach for corticotomy procedures. The researchers made the patients rinse their mouth with an antiseptic mouthwash and then placed a stabilized scalpel on the attached gingiva interradicularly as to make an angle of 45–60 with the long axle of root of the teeth and applied cortical incisions via a surgical hammer without removing flaps [42]. Incisions were applied as 2/3 of the roots vertically and in 10 mm depth. Corticision area must be cleaned with physiological saline solution until hemorrhage stops. Park reported that fixed orthodontic treatment of a patient without extraction was completed in a short period of 10 months through this method. Although corticision method is minimally invasive with a short surgical intervention, it is not widely accepted as it

Micro-Osteoperforations

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http://dx.doi.org/10.5772/intechopen.81419

is not appropriate to grafting and the surgical technique is disturbing for the patience.

pare corticotomy-assisted methods with piezoincision method [44].

results but it must be evaluated by further clinical studies.

In 2009, Dibart et al. [43] introduced a minimally invasive technique that can be applied by piezosurgical tools, the piezoincision method, which can be carried out without any flap surgery as in corticision method but it allows hard or soft tissue grafting differently. In this method, small piezoelectric incisions are placed in the area from the targeted corticotomy area to periost. Piezoincisions of 3 mm length and depth are applied with the piezosaw without removing mucoperiosteal flap. In this stage, mucoperiosteal flap can be removed as a tunnel and a bone graft in pad form can be replaced if necessary. Sutures are required if grafting is applied, otherwise there is no need for sutures. It was reported that no significant difference was found in terms of tooth movement speed and root resorption in the studies which com-

Piezoincision is a practical, minimally invasive, and effective method. Additionally, ultrasonic vibrations which occur during the procedure in piezoincision method also contribute to accelerate tooth movement [3]. Required precautions must be taken before the procedure with patients in high-risk group due to possibility of temporary bacteremia formation risk

"Piezopuncture" method, which is applied by using an ultrasonic piezosurgical tool, "piezotome" without gingival incisions in piezoincision method was developed by Kim et al. [45]. In their study on 10 dogs, the researchers created several cortical punctures both buccally and lingually on the mesial and distal sides of the teeth which will be moved and reported that anabolic activity and tooth movement were accelerated at the end of the procedure. Omidkhoda et al. who carried out piezopuncture technique on human reported that tooth movement was accelerated but they observed distal tilt in the canine teeth crowns in their case reports which consist of two cases [46]. "Piezopuncture" method also takes part in literature as a method with promising positive

Although a faster canine distalization is achieved with less teeth tilting in dentoalveolar distraction method when compared to periodontal ligament distraction method, it is clear to be a more invasive method [36].
