Abstract | | |
Introduction: The number of adult patients seeking orthodontics treatment has increased drastically. There is increased need for faster tooth movement and good esthetics. Piezocision is one of the methods used for accelerating the rate of tooth movement. Aims and Objectives: To assess the amount of root resorption after retraction of canine through piezocision site and compare it with that of recently extracted site using cone-beam computed tomography (CBCT) and assessment of dentin sialoprotein (DSP) levels in gingival crevicular fluid (GCF). Materials and Methods: A split mouth design was used in 15 patients who were undergoing first orthodontic treatment with premolar extractions. Randomly one of the sides was chosen as control (Group I) and the other side underwent piezocision procedure (Group II). 0.022 × 0.028'' MBT system was used with 0.017 × 0.025 SS wire for canine retraction using 150 grams of force. GCF samples were collected from mesio-buccal and disto-buccal of the canine with micropipette at baseline (TO) and day 90(T1) to detect the levels of DSP and the root resorption was measured using CBCT. Results: Statistically significant amount of root resorption was observed after retraction in both the groups. DSP levels were increased in both the groups, though little higher in Group II when compared to group I. Conclusion: DSP level was increased on the piezocision side but it was statistically insignificant which suggests the amount of root resorption on both the sides is similar.
Keywords: Biomarker, dentin sialoprotein, GCF, piezocision, root resorption
How to cite this article: Ravi M S, Murali P S, Kumari V, Hamidi W, Sneha K, Soans C. Radiographic and histochemical assessment of root resorption during canine retraction through piezocision site. Indian J Dent Res 2021;32:448-52 |
How to cite this URL: Ravi M S, Murali P S, Kumari V, Hamidi W, Sneha K, Soans C. Radiographic and histochemical assessment of root resorption during canine retraction through piezocision site. Indian J Dent Res [serial online] 2021 [cited 2023 Mar 21];32:448-52. Available from: https://www.ijdr.in/text.asp?2021/32/4/448/345430 |
Introduction | |  |
The increased orthodontic treatment time leads to various detrimental effects such as gingival inflammation,[1] white spot lesions, dental caries and root resorption.[2] Apart from these effects, the patient also shows less compliance towards the later part of the treatment.
Hence, various methods[3] are being used like local and systemic drug administration,[4],[5] mechanical and physical stimulation[6],[7],[8],[9] and different surgical[9],[10],[11],[12],[13],[14],[15],[16] procedures to reduce the orthodontic treatment time.
Introduction of newer minimally invasive,[17] predictable surgical techniques has been the main focus of many clinicians in recent times. Piezocision is one such surgical technique which has been employed to reduce the treatment time. In this procedure, following a linear incision in the inter radicular area, injury is made by a curved Piezotome tip to a depth of approximately 3 mm and length of 4–6 mm. Piezocision causes physical damage, which is responsible for the initiation of temporary demineralisation process along with regional acceleratory phenomenon (RAP),[18],[19] which was first observed by Frost (1983). It is a tissue reaction to a noxious stimulus that increases the bone turnover rate. It is not only seen in hard tissue but also in soft tissue. Mechanical injury, hypoxia, or inflammatory stimuli cause the activation of osteoblasts. These activated osteoblasts lead to the expression of specific mediators, which further are responsible for activation of the osteoclasts leading to bone bone resorption. This is followed by bone deposition by the osteoblasts increasing rate of bone turnover, which finally leads to an increased rate of tooth movement.
Studies have correlated the rate of tooth movement and root resorption with that of the enzymes and protein levels in gingival crevicular fluid (GCF). The dentin sialoprotein (DSP) values are related to the amount of root resorption occurring during orthodontic treatment.[20]
With this review of literature background, the present study is planned and designed to assess the changes of DSP in GCF and root resorption during orthodontic tooth movement following piezocision, and compare them with that of the tooth movement without piezocision.
Materials and Methods | |  |
The present study was carried in 15 patients requiring bilateral first premolar extraction as a part of their orthodontic treatment. Individuals in the age group of 18 to 26 years who were healthy with no history of orthodontic or facial surgical therapy were selected. Individuals with poor oral hygiene, intraoral soft tissue lesions and who had a fracture of cortical bone during extractions were excluded from the study. Written informed consent was obtained from all the individuals participating in the study. The Institutional Ethics Committee approved the study vide reference No. ABSM/ EC/62/2015.
After obtaining the ethical clearance from the institutional ethics committee reference No. ABSM/ EC/62/2015, the study was carried out using the split-mouth technique. One of the sides was selected at random as a control site (Group I), and the contralateral side was selected as the experimental site (Group II).
The 0.022” MBT system was used for all the patients. 0.014'' NiTi was used for initial leveling and aligning followed by 0.016'' NiTi and 0.016'' × 0.022'' NiTi and 0.017'' × 0.025'' Stainless Steel (SS) wire. Once the patient was in 0.017'' × 0.025'' SS wire and ready for canine retraction, extraction of the first premolar on both sides was carried out. The experimental side underwent piezocision procedure on mesial and distal aspects of the canine [Figure 1] and [Figure 2].
A small incision was given at mesial and distal to canine, and a piezoelectric hand-piece with sharp, curved tip was used for the cortical perforation by penetrating the cortical bone through the incision by holding the tip perpendicular to the gingiva.
Canine brackets on both the sides were ligated using 0.009”SS ligature wire. A standardised force of 150 g per side was applied using elastic chain bilaterally immediately after the 1st premolar extractions.
The records were analysed prospectively by a single observer. The cone-beam computed tomography (CBCT) images were made using Planmeca ProMax™ Machine (230–240 V, 50 Hz, 16 A) manufactured by Planmeca OY (Helsinki Finland). The images recorded were analysed using the Planmeca Romexis Viewer (Version 4.1.2). Medium FOV images were measured, with a voxel slice of 0.2 mm. The 3D images were reconstructed in the implant view. Root resorption of maxillary canines was assessed by measuring the difference in length of the long axis of the tooth pre and post retraction in both the groups using CBCT [Figure 3].
GCF collection
Selected patients were asked to rinse their mouth vigorously with water. The intended tooth was isolated using cotton pellets. 1–5 μL calibrated volumetric micro-capillary pipette was used to collect 1 μL of the GCF from the distobuccal and mesiobuccal aspect of the canines. The volumetric micropipette was placed extra crevicularly, and standardised volume of GCF (1 μl) was collected before retraction (TO) and again after 90 days of retraction (T1) on both the sides from the canine region.
Sample preparation
100 microliters of phosphatase buffered saline with 0.05% bovine serum albumin (Sorensens medium) of pH 7 was transferred to a vial using 100 μl micropipette.
The quantity of buffer pipetted was 100 times the volume of the crevicular fluid collected.
The vial containing GCF was sealed, labeled and immediately transferred to the laboratory where it was centrifuged for 1 min for removal of the bacterial and cellular debris. Enzyme level was then assayed.
Dentin sialoprotein
Enzyme-linked immuno-sorbant assay (ELISA) for DSP was used. It was pre-coated with polyclonal antibody, which was specific for human DSP and consisted of 96 wells. 100 mmol phosphate-buffered solution was used as a buffering agent. The control and the experimental samples were assayed in duplicates. A spectrophotometer was used to measure the optical density (OD) set at 450 nm. Then the DSP concentration level was analysed using this formula.
DSP concentration = (OD of Test/OD of Standard × Dilution factor) × Concentration of standard.
The data were analysed using frequency percentage, mean and standard deviation. Paired “t' test was used to compare the difference in between the groups.
Results | |  |
In this study, fifteen patients underwent orthodontic treatment, which required extraction of upper first premolars as a part of their treatment plan. It was a split-mouth design where one of the sides was chosen for piezocision procedure at random. The side where piezocision was not done acted as control (group I), whereas the side on which piezocision was performed was experimental side (group II).
A quantitative analysis of a protein, DSP, was also done at TO (baseline) and T1 (day 90).
Dentin sialoprotein
The mean level of DSP in the group I at the baseline TO was 2.617 ± 1.26 ng/ml (mean ± SD). It increased to a level of 53.731 ± 5.48 ng/ml at T1 [Table 1] and [Graph 1]. | Table 1: Comparison of DSP levels between the groups at different time intervals
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The mean level of DSP in Group II at the baseline TO was 2.657 ± 0.67 ng/ml (mean ± SD). It increased to a level of 55.59 ± 5.11 ng/ml at T1.
It was observed that the values in Group II were higher than Group I at both TO and T1, but the difference was statistically insignificant with P < 0.001.
Root resorption
Root resorption was statistically non-significant from T0 to T1 when compared between group I and group II and also within the group [Table 2], [Table 3] and [Graph 2]. | Table 2: Root resorption between Group I and Group II at different time intervals
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Discussion | |  |
The number of adult patients seeking orthodontic treatment has increased tremendously in the recent decade. With the increasing average age of the orthodontic patient, there is a concomitant increase in the demand for faster and efficient orthodontic treatment. In comparison to the younger age group, the cell mobilisation and bone turnover are much slower in adult patients. They are more prone to periodontal complications since their teeth are fixed in the relatively nonflexible bone. Hence, the orthodontic treatment is more challenging in adult patients.
The biomechanical proficiencies in orthodontics have been enhanced as a result of the continued evolution of different wire and bracket systems. The average time taken for the orthodontic treatment ranges from 12–36 months, depending on the system used and individualistic response of each patient to orthodontic forces. There are many disadvantages of long treatment time. Few of them are reduced patient compliance and increased cost and biological factors like apical root resorption,[2],[3] periodontal breakdown, dental caries,[1] and decalcification/white spot lesion on the teeth. To combat these disadvantages several novel modalities have been reported to accelerate the tooth movement like local and systemic drug administration,[4],[5] mechanical and physical stimulation, Low-level laser therapy,[8] pulsed electromagnetic fields,[7] low-level electrical currents,[6] corticotomy,[11],[12] distraction osteogenesis,[9],[10] mechanical vibrations/ acceledent, wilckodontics[13],[14] micro-osteo perforation and piezocision.[15],[16]
Surgical methods have been used since long to accelerate the rate of tooth movement and it was based on the principle of regional acceleratory phenomenon (RAP)[18],[19] as external injury causes an inflammatory cascade which causes an increased rate of bone remodeling and hence the faster tooth movement. The older techniques were more invasive and technique sensitive. Thus, it was not very well accepted by the patient and that led to the development of new minimally invasive techniques like MOP and piezocision with similar results as the older techniques.
Piezocision technique involves the use of piezocision knife for giving vertical cuts mesial and distal to the canine, in the interdental region apical to the alveolar crestal bone. The cut is around 3 mm in depth and 4–5 mm in length and only involves the cortical plate of the bone. This injury to the bone is sufficient enough for increasing the rate of tooth movement and causes minimal discomfort to the patient.
In the present study, root resorption was measured with the help of CBCT and it was found that there was no difference in the amount of root resorption between the two groups post retraction, but statistically significant root resorption was seen within both group I and group II. This was in contrast with the studies done by Generson et al.,[21] Wilcko et al.,[13] Moon et al.[22] and Abbas et al.,[23] where root resorption was lesser on the corticotomy side compared to that of control. The present study was in accordance with Gantes et al.,[24] who found apical root resorption with surgically assisted tooth movement, and the same amount was found in the non-surgically assisted tooth movement as well. However, Patterson et al.[25] have different results where they reported more root resorption on the piezocision side compared to that of control. The reduced root resorption between the groups was also because of reduced cortical resistance due to faster bone metabolism and lesser build-up of pressure hence lesser chances of hyalinisation.
Root resorption is collateral damage which happens alongside orthodontic treatment. It reported in the literature that the orthodontic treatment leads to the apical resorption of the tooth root. McNab et al.[26] have reported that there is root resorption occurring due to orthodontic forces. They also gave different factors influencing resorption. Extraction is one of the factors.
Huang et al.[27] have also reported apical root resorption after space closure in extraction cases.
Kareshenan et al.[28] reported an increased level of DSP in GCF obtained from the patients undergoing orthodontic treatment.
In this study, samples were collected at two-time intervals, first at baseline (TO) and other at 90th day (T1) into the retraction.
DSP level at T1 was higher than baseline on both the sides and values for the piezocision site was marginally higher than the non-piezocision side, but it was not statistically significant. Hence, it suggests that the root resorption is occurring during the retraction of canine and is slightly higher on the piezocision side, but it is not harmful.
Conclusion | |  |
In the present split-mouth study comparing the rate of canine retraction in recent extraction site with and without piezocision the following conclusions may be drawn.
- There was no statistically significant difference in the root resorption between the two groups as assessed in CBCT
- Dentin sialoprotein was found higher on the piezocision side when compared to non-piezocision side, but this difference was statistically insignificant, which suggests that there is no higher risk of root resorption when piezocision is done
Within the limitations, the present study indicates that the clinical procedure of peizocision does not increase the chances of root resorption when compared to the conventional method. The piezocision is therefore a safe clinical method that could be used as an adjunct procedure during orthodontic tooth movement.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References | |  |
1. | Artun J, Brobakken BO. Prevalence of carious white spots after orthodontic treatment with multibonded appliances. Eur J Orthod 1986:8:229-34. |
2. | Kurol J, Owman-Moll P, Lundgren D. Time-related root resorption after application of a controlled continuous orthodontic force. Am J Orthod Dentofacial Orthop 1996;110:303-10. |
3. | Aulikci O, Sakin C. Piezocision assisted canine distalization. J Orthod Res 2013;1:70-6. |
4. | Chumbley AB, Tuncay OC. The effects of indomethacin on the rate of tooth movement in cats. J Dent Res 1981;60:596. |
5. | Collins MK, Sinclair PM. The local use of vitamin D to increase the rate of orthodontic tooth movement. Am J Orthod Dentofacial Orthop 1988;94:278-84. |
6. | Davidovitch Z, Finkelson MD, Steigman S, Shanfeld JL, Montgomery PC, Korostoff E. Electric currents, bone remodeling, and orthodontic tooth movement. II. Increase in rate of tooth movement and periodontal cyclic nucleotide levels by combined force and electric current. Am J Orthod 1980;77:33-47. |
7. | Stark TM, Sinclair PM. Effect of pulsed electromagnetic fields or orthodontic tooth movement. Am J Orthod Dentofacial Orthop 1987;91:91-104. |
8. | Kawasaki K, Shimizu N. Effects of low-energy laser irradiation on bone remodeling during experimental tooth movement in rats. Laser Surg Med 2000;26:282-91. |
9. | Liou EJ, Hung CS. Rapid canine retraction through distraction of periodontal ligament. Am J Orthod Dentofacial Orthop 1998;114:372-82. |
10. | Leethanakul C, Kanokkulchai S, Pongpanich S, Leepong N, Charoemratrote C. Intcrseptal bone reduction on the rate of maxillary canine retraction. Angle Orthod 2014,84:839-45. |
11. | Kõle H. Surgical operations on the alveolar ridge to corret occlusal abnormalities. Oral Surg Oral Med Oral Pathol 1959;12:515-29. |
12. | Fitzpatrick BN. Corticotomy. Aust Dent J 1980;25:255-8. |
13. | Wilcko WM, Wilcko T, Bouquot JE, Ferguson DJ. Rapid orthodontics with alveolar reshaping: Two case reports of decrowding. Int J Periodontics Restorative Dent 2001;21:9-19. |
14. | Wang B, Shen G, Fang B, Yu H, Wu Y, Sun L. Augmented corticotomy assisted surgical orthodontics decompensates lower incisors in class II malocclusion patients. J Oral Maxillofac Surg 2014;72:596-602. |
15. | Dibart S, Surmenian J, Scbaoun David J, Montesani L. Rapid treaiment of Class II malocclusion with piezocision: Two case reports. Int J Periodontics Restorative Dent 2010;30:487-93. |
16. | Aksakalli S, Calik B, Kara B. Ezirganli S. Accelerated tooth movement with piezocision and its periodontal-transversal effects in palients with Class II malocclusion. Angle Orthod 2016;86:59-65. |
17. | Seok Kim Y, Jung Kim S, Joo Yoon H, Joohak Lee P, Moon W, Guk Park Y. Effect of piezopuncture on tooth movement and bone remodeling in dogs. Am J Orthod Dentofacial Orthop 2013;144:23-31. |
18. | Frost HM. The regional acceleratory phenomenon: A review. Henry Ford Hosp Med J 1983;31:3-9. |
19. | Düker J. Experimental animal research into segmental alveolar movement after corticotomy. J Maxillofac Surg 1975;3:81-4. |
20. | Kisnisci R, Iseri H, Tuz I, Altug A. Dentoalveolar distraction osteogenesis for rapid arthodontic canine retraction. J Oral Maxillofac Surg 2002;60:389-94. |
21. | Generson RM, Porter JM, Zell A, Stratigos GT. Combined surgical and orthodontic management of anterior open bite using corticotomy. J Oral Surg (American Dental Association: 1965). 1978;36:216-93. |
22. | Moon CH, Weeb J, Lee H. Intrusion of overerupted molars by corticotomy and orthodontic skeletal anchorage. Angle Orthod 2007;77:1119-25. |
23. | Abbas NH, Sabet NE, Hassan IT. Evaluation of corticotomy-facilitated orthodontics and piezocision in rapid canine retraction. Am J Orthod Dentofacial Orthop 2016;149:473-80. |
24. | Gantes B, Rathbun E, Anholm M. Effects on the periodontium following corticotomy-facilitated orthodontics. Case reports. J Periodontol 1990;61:234-8. |
25. | Patterson BM, Dalci O, Papadopoulou AK, Madukuri S, Mahon J, Petocz P, et al. Effect of piezocision on root resorption associated with orthodontic force: A microcomputed tomography study. Am J Orthod Dentofacial Orthop 2017;151:53-62. |
26. | McNab S, Battistutta D, Taverne A, Symons AL. External apical root resorption following orthodontic treatment. Angle Orthod 2000;70:227-32. |
27. | Huang Y, Wang X-X, Zhang J, Liu C. Root shortening in patients treated with two-step and En masse space closure procedures with sliding mechanics. Angle Orthod 2010;80:492-7. |
28. | Kereshanan S, Stephenson P, Waddington R. Identification of dentine sialoprotein in gingival crevicular fluid during physiological root resorption and orthodontic tooth movement. Eur J Orthod 2008;30:307-14. |

Correspondence Address: Dr. M S Ravi Professor and Head, Department of Orthodontics and Dentofacial Orthopaedics, A B Shetty Memorial Institute of Dental Sciences, Nitte (Deemed to be University), Mangalore - 575 018, Karnataka India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/ijdr.IJDR_654_19

[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3] |