Prolonged duration of treatment is one of the issues in the field of orthodontics
Prolonged duration of treatment is one of the issues in the field of orthodontics. Search for techniques that decreases the treatment period without hindering the result is challenging. Minimizing treatment duration reduces threat of caries, periodontal disease, resorption of root, and contents the patient as well. Many trials have been conducted so as to minimise the time of treatment. Figuring out these challenges will dramatically improve the quality of orthodontic care.
It is an established fact that speed of orthodontic tooth movement (OTM) which in turn guarded by the osteoclast activity, guarded with time of bone resorption. Factors influencing the time upon which these method happen may have an result on OTM. To transform the equilibrium between resorption and apposition of bone the regional acceleratory phenomenon (RAP)4 has been used during any means possible.
The periodontium consists of gingiva, periodontal ligament (PDL), cementum and alveolar bone. Among all, alveolar bone is generally mineralized and is not easily malleable. It is dynamic enough and to controlling its remodeling capability has constantly been tough tough on the part of peridontic and even orthodontic perspective. These days the trend of interdisciplinary co-operation is prevalent over the same old conventional orthodontic tooth movement protocol and also volunteer periodontal tissue effort & regenerative surgery, which would not only be effective for accelerating the orthodontic tooth movement but also would give new possibilities for young practitioners to minimise adverse affects like resorption of root, relapses, inadequate basal bone, bacterial caries and infection. Besides, this apprehension among the adolescent population regarding the period of the treatment has come to a resolution with these newly designed approaches.
The common perception that pre existing alveolar volume is irreversible has located significant limits on the extent of tooth movement considered to be safely reachable and at rest give a firm result.8,9The changes in the structure of alveolar bone is the prime factor of orthodontic tooth movement and the rate of remodelling is accelerated during osseous wound healing. To achieve quicker results, several attempts have been made both preclinically and clinically, yet these methods are pretty questionable.
In the periodontal ligament, cellular responses are brought about by orthodontic force, which carry on bone resorption on the pressure side & deposition on the tension side. This occurs by means of induction of osteoclasts through RANK-RANKL pathway and occurrence of different inflammatory mediators like IL-1, IL-8, TNF-alpha etc. Experiment have been done to accelerate orthodontic tooth movement with local/systemic administration of biological mediators such as prostaglandins, interleukins, leukotrienes along with vitD. Involving in the development of osteoclasts from precursor monocytes, or recovering capillary permeability. These can increase periodontal regeneration by inducing or hastening orthodontic inflammation. Since, long to increase tooth movement surgical methods have been used. Therefore, reason for speed tooth movement (Regional Acceleratory Phenomenon or Periodontally Accelerated Osteogenic Orthodontics) these techniques were based on the concept that when the bone is irritated surgically, an inflammation cascade is initiated which causes greater osteoclastogenesis.
In the past 20 years, to advance bracket design and treatment procedures many innovative techniques have been introduced to enhance the design of brackets through the proven promising method increase the rate in which the teeth drift through alveolar bone involve extensive surgery. The challenge has been how to locally increase bone remodelling in a non-invasive fashion.
Most reports of accelerated tooth movement involved laying a flap and performing fairly extensive corticotomy on the surface of the alveolus around the roots of teeth and the use of heavy orthodontic force to move teeth rapidly. It was suggested that cuts between the teeth could provide faster tooth movement, but this was viewed as unnecessarily invasive and was not widely accepted.
Hence, investigation for procedures which reduces the duration of treatment with no hinderance to the outcome is a major confront in orthodontic therapy. Various researchers tried to discover minimally invasive surgical procedures to induce regional acceleratory phenomenon. Recently Treixeira et al16 using micro osteoperforations has revealed the fact that biological principles can be activated to increase bone remodelling. Micro osteoperforation is said to be the only micro-invasive method to enhance orthodontics. MOP builds predictable orthodontic treatment results, improves finishes with braces, & reduces or eliminates refinements with clear aligner therapy. Studies done on animals have evidences about the fact that when we perform MOPs during orthodontic tooth movement on alveolar bone, it can act as a stimulus to express these inflammatory markers, hence increasing the osteoclast activity and increase in the tooth movement speed.
There are very few studies available in the literature which investigates that such phenomenon occurs in humas or not. But none of the study till now has been done by using miniscrews / miniimplants of specified dimension for the purpose of micro-osteoperforations. Thus this clinical trial was done to study the span of canine retraction with Micro-Osteoperforations or without using it and also to evaluate the pain and discomfort caused to the patients during the treatment.
This study is aimed at evaluating and comparing effects of modified micro-osteoperforations on the rate of tooth movement.
To evaluate the effect of modified micro-osteoperforations on the rate of tooth movement.
To compare it with the control group on the contra lateral side.
To assess the pain and discomfort level in the patients during the treatment with and without Micro-osteoperforations using a numerical rating scale.
Orthodontic mechanotherapy is carefully designed into various stages in order to achieve an optimal treatment outcome. At certain stages, some teeth are intended to move while others serve as anchors. MOP can be selectively applied on particular locations to decrease the bone density around the target tooth while the bone density around the anchor unit remains unchanged. Therefore the clinical advantage of MOP is the ability to titrate the rate by establishing “Biological Anchorage” while accelerating the movement of target teeth.
Corticotomy and Piezocision procedures can cause more extensive trauma in broader areas, therefore stimulating a higher amount of pro-inflammatory cytokines. Although they can be preferable in certain clinical situations, the level of inflammatory markers decreases significantly 2–3 months after surgery. Therefore, if a longer distance of tooth movement is required, MOP is the procedure of choice as it can be applied periodically until the desired movement is achieved.
MOP can also facilitate root movement, which is deemed to be the most difficult movement to accomplish in orthodontics. By activating osteoclasts and decreasing the bone density, MOP can decrease the stress on the root during movement and therefore decrease the possibility of root resorption.
Following conclusions can be drawn from the current study
There is statistically significant increase in the rate of canine retraction using modified micro-osteoperforationsas compared to control side.
When compared with the control side, MOPs increased the rate of canine retraction 2.13 fold.
Statistically significant increase in the rate of canine retraction using modified micro-osteoperforations in female as compared to male on MOPs side was observed.
Patients reported only mild discomfort locally at the place of the MOPs intially. Little to no pain was experienced after 14th day.
Pain and discomfort was more in female as compared to male at the place of MOPs on the 1st day.
Micro-osteoperforations are simple, comfortable, effective, and minimally invasive method to accelerate tooth movement and to decrease the treatment period.
Micro-osteoperforations done using skeletal anchorage screws and driver in our study can be a helpful method in large space closure, correction of third molar inclination, molar protraction and difficult tooth movements.
Study Design: Prospective clinical study was designed to know and compare the effect of modified micro-osteoperforations on tooth movement rate.
Source of Data: Department of Orthodontics and Dentofacial Orthopedics, Teerhanker Mahaveer Dental College & Research Centre, Moradabad was where the study has been conducted.
Consent: A detailed informed written consent form was signed by each patient’s parents or guardians, who were willing to participate in the study ; his or her treatment.
Ethical Clearance: Ethical clearance was obtained before the beginning of this study from the institution ethics committee of Teerthanker Mahaveer Dental College ; Research Centre, affiliated to Teerthanker Mahaveer University, Moradabad.
Sample Size: Twenty patients (10 males and 10 females) undergoing fixed orthodontic treatment in the Department of Orthodontic and DentofacialOrthopaedics, TMDCRC, Moradabad were taken for the study.
Study Period: 12 – 18 months.
Patients with Angle’s Class II Div1 malocclusion (indicated for bilateral maxillary first premolar extraction) or Class I Bimaxillary protrusion (indicated all first premolar extraction)
All subjects with age group of 18 – 30 years.
All subjects undergoing treatment with Pre-adjusted Edgewise Appliance (PEA) with 0.022 MBT prescriptions.
Subjects who have completed the leveling and alignment (1st Phase).
Absence of systemic disease.
No evident radiologic picture of bone loss.
No history of periodontal disease.
Absence of currently present and ongoing periodontal disease.
Absence of smoking habit.
Untreated caries or absence of gingivitis.
Previous history of orthodontic treatment
Presence of craniofacial anomalies
Presence of any signs and symptoms of gingival and periodontal diseases
Long term use of cyclosporin, phenytoin sodium, systemic corticosteroids, calcium channel blockers and anti-inflammatory drugs.
Oral hygiene compromised evident since the past two visits.
Evidence of bone loss
Past periodontal disease
Gingivitis and caries
Materials and equipment’s used in this study are:
MBT-0.22 Slot (3M- UNITEK). (Figure 1)
Maxillary canine bracket with vertical slot (American Orthodontics) (Figure 2)
Digital verniercalliper (Figure 3)
Pre-calibrated Ni- Ti closed coil springs (100 gm force – GAC) (Figure 4)
Temporary anchorage device ( S. K Surgicals) (Figure 5)
Power arm engaged in vertical slot of canine brackets (Figure 2)
William’s Graduated probe
Alginate impression material
Type III dental stone
Disposable 26 gauge needles and syringes (Figure 6)
Lignox (2%lidocaine with 1:100000 epinephrine) (Figure 6)
Mouth mirror, explorer and tweezers
Pre-retraction and post retraction study models(Figure 7)
Method of Collection of Data
The comparative clinical trial was conducted from the beginning of 2nd Phase (space closure phase) of fixed orthodontic treatment, for duration of 28days.
A split mouth type of study design was done where the maxillary arch of each subject was divided and randomly selected into experimental side (micro-osteoperforation was done) and control side (no micro-osteoperforations was done). In the experimental group modified MOPs was done either on the right side or the left one, in order to eliminate possibility of uneven occlusal forces. A key advantage of this study design is because of this fact that every patient acts as his or her own control, so much of the inter subject variability is removed, that results in increase in the study power or reduction in the participant count needed in comparison a study where patients undergo only a single intervention.
Twenty patients (10 males and 10 females) with Class II Div1 malocclusion or Bimaxillary protrusion who needs maxillary first premolar extractions entering the retraction phase of fixed orthodontic treatment were selected for the comparative clinical trial. All participants were given a brief on the principle of the study and an informed consent was taken from the subjects or their parents before undertaking the study.
Orthodontic Appliance and Canine Retraction Procedure
All the subjects were bonded with PEA, 0.022 x 0.028 inch 0.022 MBT prescription. On maxillary canines American Orthodontics brackets with vertical slots were bonded.
Following the extraction of maxillary first premolars, initial alignment was done. Segmental retraction of maxillary canines was done on 0.019 x 0.025 inch S.S.(stainless steel) wire using power arm in the vertical slot of the canine brackets. 0.019 x 0.025 inch wire remained in situ till four weeks before the commencement of retraction (Figure 8). This period enable full arch wire passivity before the retraction of the maxillary canines.
Maxillary arch impressions were made by using alginate at the end of leveling and aligning stage. Impressions were then poured using Type III orthodontic dental stone.
Maxillary canine of one quadrant were retracted with micro-osteoperforations and the other quadrant maxillary canine was retracted without micro-osteoperforation(Figure 9). Experimental side and control side were assign to the patient’s left or right sides consecutive. Nickel-Titanium closed coil springs were used to achieve segmental retraction of cuspids that were connected from a temporary anchorage device(TAD) to a power arm on the canine bracket that allowed application of the force closer to the center of resistance of the tooth. TAD was positioned between 2nd premolar and 1st molar, 5 mm from the alveolar crest and loaded immediately. A retraction force of 100 grams was applied using pre calibrated NiTi closed coil spring (GAC)(Figure 10). At each appointment, oral hygiene measures were reinforced and the appliances were assessed for any damage.
Micro Osteo-perforation Technique
Modified-MOPs was performed in local anaesthesia (2% lidocaine by 1:100,000 epinephrine) and through standard asepsis. No flap was raised. Three modified-MOPs were performed gingival to the extraction site (either on the left/right side) distal to the canines at coronal, middle and apical regions, using a miniscrew implant (depicted in patient model Figure 11) . The soft tissue thickness was measured using a needle with a stopper before performing each modified-MOP. A rubber stopper was used to standardize the depth of penetration of the miniscrew implant (Figure 12). 3small MOPs were done in the extraction space, immediately distal to the canine but without causing any interference to the root. 1.5 mm wide and 3 mm deep into the bone was the common size of all the perforations.
Retraction of canine bilaterally was achieved by means of pre-calibrated 100gmNiTi closed coil springs connected from a temporary anchorage device (1.5 X 8 mm) put between the upper 2nd premolar and 1st molar, 5mm from the alveolar crest and loaded immediately.
Post retraction records were made, 28 days later the commencement of retraction of cuspids.
Measurement of Rate Tooth Movement
All the measurements were performed on the dental casts. Prior to the studies, alginate impressions were made immediately before the retraction of canine i.e pre-retraction model and also 28 days after the retraction of canine i.r post-retraction model.
for monitoring the tooth movement rate. The impressions were instantly poured into casts of dental stone and were given the labels of patient’s name, date in order to store. Over the palatal surface of the canine from the middle of the incisal edge to the middle of the cervical line, vertical lines were drawn. The space in between the lateral incisor and the cuspid is measured prior to the retraction of canine and also after it at 3 points: incisal, middle, and cervical thirds of the crowns. All cast measurements were made using a digital vernier caliper of an accuracy 0.01mm
All measurements were done by the single observer. To assess the intra-observer error, measurement of models were done twice at least after two weeks models. Method fault was evaluated by using Dalhberg’s formula.
Assessment of Pain and Discomfort Levels
On the day of canine retraction, the participants were asked to assess their level of discomfort and at 24 hours, 7 days, and 28 days after canine retraction subsequently with a numeric rating scale, a high reliability tool comparable with a visual analog scale. Instructions were given to the patients so as to choose a number (from 0 to 10) that best describes the pain: If the count comes 0 then it will be defined as “no pain” and if it comes to 10, then it would be defined as the “worst possible pain.
The data collected for the canine retraction, assessment for pain & discomfort were first tabulated to Excel (Microsoft, Redmond, Wash). The data obtained were subjected to following statistical analysis.
Following statistical analysis were used to measure the rate of tooth movement
To compare the pre and post canine retraction distance in control and experimental side paired t- test was used
Pair-wise multiple comparison analysis was performed with the Turkey post hoc test. Comparisons between three sites (incisal, middle and cervical thirds) were assessed by analysis of variance (ANOVA).
To compare the rate of canine retraction between males and females in control and experimental side unpaired t- test was used
All statistical analysis was done on SPSS 21.0 software for Windows (SPSS, Chicago, III). Significance for all analytical tests was fixed at p <0.05.
The following statistical formulae were used for statistical analysis of data:
1. Mean: Is defined as the sum of the values divided by the number of values and is assigned as X.
X = ?XnX = Mean of the sample
? = Sum
X = Variable
n = sample size
2. Standard deviation: Is defined as root means square deviation and is denoted by? (sigma) or SD
SD = Standard deviation
X = Mean
X = The values of the variables
? = Sum of variables
n = No. of observations
3. Standard error of the mean: Is the standard aberration of specimen mean assessment of a group. Standard error of mean is commonly assessed by the sample assessment of the samples of group standard aberration divided by the square root of the specimen size (domineering statistical independence of the values in the specimen).
s is the specimen standard deviation (i.e the sample based assessment of the standard aberration of the samples), and n is the size (number of observations) of the sample.
4.Studentt-test: This test was performed to understand the significant statistical difference between two independent sample means.
i.e., whether X1 and X2 are significantly different
t = X1 – X2
SE(X1 – X2) = Standard Error of difference
=S1n?+1n?Here S = Combined standard deviation
Combined standard deviation
X1 = Mean of first sample
X = Mean of second sample
n1 = Sample size of first sample
n2 = Sample size of second sample
S1 = Standard deviation of first sample
S2 = Standard deviation of second sample
(n1 + n2 – 2) = Degree of freedom.
5. ANOVA: The analysis of variance test was done to see note stastically significant among between the means of the three groups if any. The formula used was –
SB = Sum of squares between the groups.
Sw= Sum of squres within the groups.
sB= Mean of sum of the squares between the groups.
sw= Mean of sum of the squares within the groups
Source of variation Sum of squares Degree of freedom Mean Square
Between SB = SSB K-1 SB
Within Sw= SSW N-K Swsw=
Total TSS N-1 6. Post-hoc Test: In practice, these analyses are commonly composed with patterns of finding and/or relation among subgroups of sampled groups that would contrarily keep on unexplored and were a technical societyto count rigorously upon a prior statistical experiments. Post hoc test reinforced the initiation by minimal feasibility that important effects will seem to have been exposed between subgroups of total sample size, when none actually remain. Post hoc analysis is a relevant experiment without which multiple hypothesis examining would immensely deteriorate, executing the opportunities of finding false positives unsatisfactory high.
‘p’ value denotes the level significance –
p> 0.05 Not significant
p< 0.05 Significant (significant at 95% CI)
p< 0.01 Highly significant (significant at 99% CI)
p< 0.001 Very highly significant (significant at 99.9% CI)
FLOW CHART SHOWING STEPS OF STUDY DESIGN (Figure 17)
Twenty patients aged between 18-30 years took part in the study who met the inclusion criteria.
Split mouth study design was used.
After extracting upper 1st bicuspids, by bonding fixed appliances in the upper arch with 0.022″ x 0.028 slot MBT prescription, treatment was initiated.
After one month of placement of 0.019″ x 0.025″ SS arch wire, alginate impressions of the maxillary arch wsere made and poured.
TAD was placed between the second premolar and the first molar, 5 mm from the alveolar crest and loaded immediately for canine retraction using a NiTi closed coil spring delivering a force of 100 grams per side. Distal to the canines, three micro-osteoperforations were performed on one side and on the contralateral side no micro-osteoperforation was done.
A temporary anchorage device to a power arm on the canine bracket, Canine retraction was achieved using nickel-titanium closed coil springs.
Alginate impressions were taken immediately before canine retraction (pre-retraction model) and 28 days after canine retraction (post-retraction) to monitor the rate of tooth movement.
Dental stone was poured into the impression and casts were prepared to perform all the measurements required for the study.
The distance between the canine and the lateral incisor was assessed before and after canine retraction at 3 points: Incisal, Middle, and Cervical thirds of the crowns.
All cast measurements were made using a digital vernier caliper in mm.
MATERIALS AND EQUIPMENT’S USED IN THIS STUDY
Figure 1: Pre-adjusted MBT Bracket kit – 0.022″ X 0.028″slot(3M Unitek)
696056499852Figure 2: Maxillary canine bracket with vertical slot (American Orthodontics) and powerarmFigure 3:Digital Vernier Caliper1279525252730
Figure 4: Pre-calibrated Nickel Titanium closed coil springs (100 gm forces – GAC)
Figure 5: S K Surgical mini-implant kit with Miniscrew implants of 1.5 X 8 mm
Figure 6: Syringe, Local anesthesia and Topical anesthesia29210151441
Figure 7: Pre and Post Retraction Study Models
33947104025901497965402590-369651402928CANINE RETRACTION BETWEEN THE EXPERIMENTAL AND CONTROL SIDE
262636042799061595430530Figure 8:Intraoral photographs with passive 19 X 25 SS wire
Figure 9:Micro-osteoperforation in the extraction space at equal distance
from the canine and the second premolar (experimental side)
Figure 10:Canine retraction by means of calibrated 100 gm nickel-titanium closed coil
springs (GAC International) connected from a temporary anchorage
device to a power arm on the canine bracket
749844298370MODIFIED MICRO OSTEO-PERFORATION PROCEDURE
Figure 11: Patient model showing modified MOPs procedure on experimental side
Figure 12: Mini-implant driver and Miniscrew (1.5 X 8 mm) with rubber stopper
Figure 13: Experimental side with three small MOPs of 1.5mm wide and 3mm
depth on extraction space
MEASUREMENT OF CANINE RETRACTION ON PATIENT’S MODEL
Figure 14: Measurement of canine retraction at 3 points: Incisal, Middle and Cerivcal third of crowns
Figure 15:Measurement of control and experimental side before and after canine retraction in patient model using digital vernier caliperASSESSMENT OF PAIN AND DISCOMFORT LEVELS
Figure 16: Assessment of pain and discomfort using “Numeric Rating Scale”
2527935422275-3810426720Intraoral photographs with passive 19 X 25 SS wire
Micro-osteoperforation in the extraction space at equal distance from the
canine and the second premolar (experimental side)
Canine retraction using calibrated 100 gm nickel-titanium closed coil springs
Figure 17 : Intraoral photographs showing steps of modified micro-osteoperforation procedure331470-21284565
The effect of the modified micro-osteoperforations in the stimulation of inflammatory markers can be evaluated at unusual time points.
The present study was a short term clinical study with only a 28 days follow-up, further studies can be done to check the effect of MOPs for longer follow up period.
Comparison of modified MOPs can be done with other invasive and non invasive procedures to check the efficiency of them in accelerating tooth movement.
Root resorption was not investigated because of the short duration of the study,future studies with longer follow up period are necessaryto evaluate rate of MOPs on root resorption.
Alginate impressions were used to fabricate dental models for measurements in the present study, further studies can be done on scanned 3D digital models using softwares for greater precision.