Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT04744337 |
| Other study ID # |
Preeti Nain |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
December 1, 2017 |
| Est. completion date |
April 1, 2019 |
Study information
| Verified date |
February 2021 |
| Source |
Postgraduate Institute of Dental Sciences Rohtak |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
The aim of this study is to document the changes brought about in the internal anatomic
relationships of the TMJ complex,positional changes of glenoid fossa with respect to adjacent
cranial structures after completion of fixed orthodontic treatment in adolescent females
initially treated with removable functional appliances for skeletal class II, Angle's class
II division 2 Malocclusion.
Description:
Angle's class II division 2 malocclusion is subtype of Angle's class II malocclusion with
unique facial, dental and craniofacial features which differentiate it from other
malocclusions so much that it has been said to be a syndrome itself. Its frequency lies
between 1.5 and 5% of all malocclusions found in a white western population. Hypertrophic
masticatory muscles as documented in class II division 2 are directed in more anterior
direction leading to increased magnitude of occlusal forces and hence increased TMJ loading.
TMJ morphology depends, to an extent on occlusal loads acting on it, so class II division 2
malocclusion patients are expected to have specific TMJ complex morphology. Condyle position
changes from anterior to posterior with age in class II division 2 cases. The use of
functional orthopedic appliances to correct Class II malocclusions associated with
retrognathic mandibles is indicated for the first phase of orthodontic treatment. A second
phase of treatment is undertaken with fixed orthodontic appliances to obtain occlusal
refinement. Although various investigations have shown the efficiency of this method of
treatment, the mechanism by which the temporomandibular joint (TMJ) responds to the treatment
is controversial.
Various techniques have been used to image the TMJ which include Magnetic Resonance Imaging
(MRI), Cephalograms, Orthopantomograms , Tomograms , Bone scintigraphy with radiologic
markers like 99mTc-MDP, Arthroscopy and Arthrography , CT scanning, Cone Beam Computed
Tomography (CBCT).
Magnetic Resonance Imaging (MRI), a multiplanar imaging technique, has the advantage of
giving an accurate assessment of both the bony and the soft tissues. This technique is
believed to be non-invasive, radiation free and gives more superior contrast resolution than
any other imaging modality. MRI is considered the imaging modality of choice for assessment
of internal derangements of the temporomandibular joint. According to Akar et al "Bony
structures and especially soft tissues of the TMJ can be examined by means of MRI and the
relations of the tissues with each other can be evaluated." MRI studies have been done on
fixed functional appliances which show significant displacement of condyle during treatment
but later condyles returned to pre treatment positions at the end of fixed functional
appliance treatment. Results documented in fixed functional appliance may not be same in
removable appliances. Effects of removable functional appliances on the condyle-glenoid fossa
(C-GF) complex have been studied with respect to the Frankel, Activator, Twin block and
Bionator appliances. Franco et al found that Frankel therapy resulted in a 'more normal'
articular disc morphology. Arat et al. concluded that disc positions were insignificant after
6 months of Activator therapy Chintakanon et al. concluded that Twin Block therapy had
neither positive nor negative effects on disc position, and there was little evidence that
the disc was recaptured. They also noted anterior positioning of the condylar head (CH) in
the glenoid fossa after 6 months of Twin Block therapy. It should be noted that all of above
studies are limited to the phase of removable functional appliance therapy only in Class II
division 1 and no MRI study has attempted to evaluate the changes in the position of the
Condyle-Glenoid Fossa (C-GF) complex treated with removable functional appliance therapy,
followed by fixed orthodontic treatment in Class II division 2 malocclusion.
Aidar et al have studied changes in temporomandibular joint disc position and form following
Herbst and fixed orthodontic treatment and found that at the end of the bi-phasic treatment
the position and form of the initial articular discs were maintained. Kinzinger, et al.
studied the effects of fixed orthodontic treatment in the case of skeletal class II on the
position of the articular disc and condyle using MRI on 20 subjects and concluded that
treatment did not alter the position of articular disc and even noticed an improvement in the
anterior disc displacement in 8 joints out of 40. No studies have been done on bi-phasic
treatment of skeletal class II, Angle's class II division 2 involving removable functional
appliances in the first phase followed by fixed orthodontic treatment in second phase.
Therefore, the aim of this study is to document the changes brought about in the internal
anatomic relationships of the TMJ complex , positional changes of glenoid fossa with respect
to adjacent cranial structures after completion of fixed orthodontic treatment in adolescent
females initially treated with removable functional appliances for skeletal class II, Angle's
class II division 2 malocclusion,
MATERIALS AND METHODS
It is a longitudinal clinical trial to evaluate TMJ disc-condyle-fossa relationship using MRI
scan following bi-phasic therapy in skeletal Class II, Angle's class II division 2
malocclusion in adolescent females.
The present study will be conducted in the Department of Orthodontics and Dentofacial
Orthopedics, PGIDS, in association with the Department of Radiology, PGIMS, and Department of
Oral Radiology, PGIDS, Pt B. D. Sharma University of Health Sciences, Rohtak.
Ethical clearance- The study will be carried out in humans after the institutional approval
obtained from ethical committee.
Source of Data The study sample will consist of the subjects from the Department of
Orthodontics and Dentofacial Orthopedics, PGIDS , who will be successfully completing the
prefunctional and functional appliance therapy for correction of skeletal class II, Angle's
class II division 2 malocclusion and will be ready for fixed orthodontic treatment for final
finishing and detailing of occlusion
INFORMED CONSENT OF THE PATIENT
A valid, bilingual informed written consent of the patient or parent/guardian will be
obtained from the patient before registering the patient in this clinical study. Patients
will be informed of all the theoretical risks and benefits of the interventions under test.
Intervention and design of study The study sample will consist of those 14 adolescent females
who had been treated initially with pre functional and functional appliance therapy for
skeletal Class II, Angle's class II division 2 malocclusion and had following MRI scans done
during the treatment
Stage- A (pre-treatment), Stage- B (after pre-functional therapy) Stage- C (After completion
of Functional Appliance Therapy) These patients will be further treated with fixed
orthodontic treatment for final finishing and detailing and an MRI will be taken after
debonding of fixed orthodontic appliance (stage D). MRI scans thus obtained will be evaluated
for documenting changes in the morphology and anatomic positions of condylar head, articular
disc and glenoid fossa and will be traced for the various angular and linear metric
measurements MRI scans of the TMJ will be obtained with a 1.5/3 Tesla Philips Intera Nova
Gradient (Netherlands) scanner equipped with Sense Head 6 channel coil for simultaneous
imaging of right and left joints. Sagittal images will be taken perpendicular to the long
axis of the condylar head and the coronal images will be taken parallel to the long axis of
the condylar head. The images will be recorded in maximum intercuspation after debonding of
fixed orthodontic appliance. The MRI protocol will include PD TSE (Turbo Spin Echo) sequence
(TR 1500/ TE 30/ FoV 150x150 mm) T1 spin echo sequences (TR 450⁄TE 15⁄FoV 160x160 mm) and T2
TSE sequence (TR 2424⁄ TE 100⁄FoV 160x160 mm).
FIXED MECHANOTHERAPY TREATMENT PHASE
The sample will be having cases in class I/ superclass I molar relation and lateral open bite
may be present in premolar regions after the completion of functional phase. The final fixed
orthodontic phase will be taken up for the final finishing and detailing of the occlusion
after the retentive phase of functional appliance therapy is completed. It involves banding
and bonding of both upper and lower arches with MBT 0.022" appliance. Progressive wire
sequences to be used are 0.014" NiTi, 0.016" NiTi, 0.018" NiTi, 0.017" x 0.025" NiTi, 0.019"x
0.025" NiTi, , 0.019"x 0.025" S.S., 0.014" S.S. Once stainless steel archwires are in place,
class II elastics may be prescribed to the patient to prevent relapse of class I molar
relation achieved. Cases are to be finished in class I molar intercuspation with normal
overjet and overbite. Appliance will be debonded and final MRI (stage D) will taken for all
the patients. Hawley's retainer with anterior bite plane will serve for retention of achieved
results
Evaluation of MRI stages
This will be done with the help of following parameters:
ANGULAR AND LINEAR MEASUREMENTS The eminence angle and the sagittal disc position measured in
relation to two reference lines: the posterior condylar line (PC line) and the Frankfurt
Horizontal plane (FH Plane). The PC line to be drawn directly on the MRI scan, while the FH
plane transferred from the lateral cephalogram to the MRI scan, according to the method given
by Nebbe et al.
Transfer of FH plane Determination of long axis of the condyle will be done by two step
circle center method by Nebbe et al.
ANGULAR MEASUREMENTS 1-2) The eminence angle and the coronal disc position will be evaluated
by the method described by Chintakanon et al.
3) The sagittal disc position will be evaluated using PC line and FH plane as described by
Chintakanon et al.
4) Sagittal condylar concentricity will be evaluated using the method described by Pullinger
et al.
5) The glenoid fossa angle will be measured on the sagittal films as the angle between the
tangents to the anterior and posterior slopes of the glenoid fossa.
LINEAR MEASUREMENTS 6) Condyle and glenoid fossa displacements: The position of the glenoid
fossa, and that of the condyle, will be evaluated with respect to the centre of the external
auditory meatus (c-EAM). by marking one point at the centre of condyle (c-CH) and the linear
distance of the c-CH from the c-EAM will be evaluated as the shortest distance from the
constructed FH perpendicular.
7) Distance between c-PGS (crest of the post-glenoid spine ) & c-EAM : One point will be
marked at the crest of the post-glenoid spine (c-PGS) and the linear distance of the c-PGS
from the c-EAM will be evaluated as the shortest distance from the constructed FH
perpendicular.
8) Superior joint space will be measured from the shortest distance between the most superior
point of the condyle and the most superior point of the mandibular fossa.
Statistical analysis The final data recorded will be processed by standard statistical
analysis.
