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RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES
BANGALORE, KARNATAKA
ANNEXURE II
PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION
1.
NAME OF THE CANDIDATE &
ADDRESS
DR. CHAITRA HALAKATTI.
POSTGRADUATE STUDENT IN THE
DEPARTMENT OF ORTHODONTICS AND
DENTOFACIAL ORTHOPEDICS,
P.M.N.M DENTAL COLLEGE AND HOSPITAL
BAGALKOT-587101
P.M.N.M DENTAL COLLEGE AND HOSPITAL
2.
NAME OF THE INSTITUTION
BAGALKOT-587101
3.
COURSE OF THE STUDY AND
MASTER OF DENTAL SURGERY IN
SUBJECT
ORTHODONTICS AND DENTOFACIAL
ORTHOPEDICS.
4.
DATE OF ADMISSION OF COURSE
31 JULY 2013
5.
TITLE OF THE TOPIC
“EVALUATION OF FORCE DEGRADATION OF
THREE DIFFERENT ELASTOMERIC CHAINS AT
VARIOUS TEMPERATURES.”
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6.
BRIEF RESUME OF INTENDED WORK
6.1 NEED FOR THE STUDY
Elastomeric chain is commonly used in orthodontics to facilitate tooth movement and
consolidate space. These polyurethane materials are manufactured as a spool of linked elastic chain,
which can be cut to the specific number of modules needed. Due to the viscoelastic properties of power
chain, however, the loss of force over time is inevitable. However, the rapid loss of an orthodontically
applied force results in inefficient tooth movement and the need for an increased number of
appointments to reactivate the appliances.
Many factors that could be controlled and uncontrolled by oral health care providers and
patients, however, have not been tested. One example of such factor is the temperature, which alters
during having food, drinks and other activities.
In the past studies were conducted to asses force degradation of elastomers chains
due to
time, the addition of dyes, chain configuration (open or closed), pre-stretch, speed and amount of
stretch, the oral environment, saliva, enzymes, exposure to light, alcohol and water. A review of the
literature shows that most of the materials have been tested in water at constant temperature and no
significant difference existed when materials were tested in water or saliva. The chemistry of salivary
enzymes and temperature variations caused by the ingestion of hot and cold foods may possibly account
for significant difference in results. These temperature fluctuations may play a role in the relaxation and
deformation of the polymer.
So the present study is to evaluate force degradation of three commercially available
elastomeric chains due to temperature changes - a comparative in vitro study.
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6.2 REVIEW OF LITERATURE:
Terrah M. Larrabeea et al1 studied the effects of varying alcohol concentrations commonly found in
mouth rinses on the force decay of elastomeric chain. A total of 450 specimens were studied in mouth
rinses containing alcohol concentration from 14% to 26.9% and force measurements were taken on 6
intervals(initial, 1st, 7th, 14th , 21st, and 28th day). They concluded that alcohol causes an increase in
force decay of elastomeric chain over time.
Concentration dependence of alcohol on force decay of elastomeric chain was not observed.
Ferriter JP, Meyers C E, Lorton L2 evaluated the effect of hydrogen ion concentration on the forcedegradation rate of orthodontic polyurethane chain elastics. The pH values of 4.95 and 7.26 were
selected for testing because they represent values close to the reported extremes of plaque and saliva
pH. Seven test elastic products were extended to (1) equal distances and (2) equal initial force levels,
and the force-degradation rates were recorded over 4 weeks.
The study concluded that the decay rate of orthodontic polyurethane chain elastics is
inversely proportional to the oral pH, with a corollary that basic pH levels are most hostile to
polyurethane chain elastics.
Nattrass C, Ireland AJ , Sherriff M3 in year 1998 conducted study to evaluate the effect of
environmental factors on elastomeric chain and nickel titanium coil springs.
The aim of this work was to determine the effect of three common environmental
factors namely, water, Coke, and turmeric solution on elastomeric chain and nickel titanium coil
springs. In addition, it was decided to re-examine the effect of temperature at 10, 22, and 37ºC on both
these space closing materials. The test specimens were held at a constant stretch throughout the test
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period, including during their transfer to the Instron Universal Testing machine for force measurement.
Six force measurements were made over the 1 hour, 24 hours and 7 days. A control group of dry
specimens, maintained at 22ºC, had additional measurements made weekly for a 4-week period.
The results indicated that elastomeric chain was affected by all the test environments.
Matheus Melo Pithona et al4 studied whether mouthwashes with and without bleaching agents
degrade the force of elastomeric chains. They studied total of 108 samples divided into 6 groups which
were immersed in Plax and Listerine mouth wash(without bleaching agent) and Plax whitening and
Listerine whitening(with bleaching agent). Immersion was done twice daily on 6 intervals (initial, 1st,
7th, 14th, 21st, and 28th day). They concluded that the presence of bleaching agent has no influence on
the force degradation of elastomeric chains.
Khudair A Al-Jumaili et al5 did evaluation and comparison of the effect of artificial saliva and
mouthwash solution on force degradation of different types of orthodontic traction aids. Samples were
extended to a specific distance which was 18 mm in case of PEC and 20 mm in case of NiTi CCS and
SS CCS. Each extended sample was then incubated in dry condition, artificial saliva, and mouthwash
solution, for total incubation period of three weeks. Results showed that samples in dry condition
always showed minimum force degradation percent than in wet conditions. It also showed that the
increase of incubation time leads to increase in force degradation percent with major degradation
percent located within first twenty four hours. They concluded that in dry and two wet conditions, NiTi
CCS reflects the lowest percent of force degradation, PEC showed highest percent, while SS CCS
showed intermediate one.
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Sarmad S Al-Kassar6 the force degradation of elastic chain in different environments and for
different intervals (an in vitro study). This study designed to determine the force degradation of
elastomeric chains (Dentaurum) at different time intervals in different media (air, distill water,
Biofresh mouth wash and artificial saliva) and to compare the effect of wet and dry conditions on the
force relaxation. The results showed that the mean percent force remaining of elastics is affected by
stretching, water absorption, chemicals and times and the amount of loss in dry is less than in wet
environments and especially in biofresh mouth wash more than the neutral saliva. They concluded that
the elastomeric chains are greatly affected by stretching, moisture and time.
6.3 AIM AND OBJECTIVE OF THE STUDY:
The aim and objective of this study are:
1.
To evaluate the effect of temperature changes on force degradation of elastomeric chains
2. To compare force degradation of three different elastomeric chains
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7.
MATERIALS AND METHODS
Study design: In vitro study
7.1 3M/Unitek.Polyurethane elastomeric chains
7.2
Ormco Glendora, CA, USA, elastomeric chains
7.3 Dentaurum , elastomeric chains
7.4
Force gauge
7.5
Frame with pin’s placed at appropriate distance so as to stretch the chains.
7.6
Incubator, so as to maintain temperature at 37oC.
7.7
Refrigerator
7.8
Thermometer
7.9
Distilled water
7.10
Electric water heater
7.11
Artificial saliva
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METHODS:

3 Different brands of elastomeric chains (60 each, total 180 number) are examined to compare
their force efficiency at three different temperature.

Elastomeric chains are divided into 4 groups A, B, C, D each group containing 15 elastomeric
chains of 3 different companies.

All 4 groups were stretched and placed on self-fabricated jig with pins placed 23.5mm apart.

Initial force of elastomeric chains are recorded using force gauge before initiation of any
procedure

Group A : immersed in distilled water maintained at 40 C-100 C for 60 seconds twice daily

Group B : immersed in distilled water bath maintained at 370 C for 60 seconds twice daily

Group C: immersed in distilled water bath maintained at 450 C for 60 seconds twice daily

Group D:immersed in artificial saliva maintained at room temperature (control group)
throughout.

After immersing Group A, Group B, Group C are immersed in artificial saliva for remaining
period.

The test period will be of 28 days. Force measurements will be performed at six different time
intervals (initial, 1st, 7th, 14th, 21st, and 28th days). This study follows the norms for testing of
elastomeric orthodontic auxiliaries (International Organization for Standardization 216062007).

The results of the study will be subjected to statistical analysis.
PLAN FOR DATA ANALYSIS
The statistical tests which will be used in this study are :
1. Descriptive statistical analysis, including means and standard deviations, will be performed for the
groups.
2. Analysis of variance (ANOVA) to determine whether there will be statistical differences among the
groups will be performed subsequently.
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INCLUSION CRITERIA
Not applicable
EXCLUSION CRITERIA
Not applicable
7.12
DOES THE STUDY REQUIRE ANY INVESTIGATION OR INTERVENTIONS TO BE
CONDUCTED ON PATIENTS OR OTHER HUMANS OR ANIMALS? IF SO PLEASE
DESCRIBE BRIEFLY
No
7.13
HAS ETHICAL CLEARANCE BEEN OBTAINED FROM YOUR INSTITUTION IN
CASE OF 7.4?
Yes, Obtained.
LIST OF REFERENCES:
1. Larrabee TM, Yao Liu SS, Gorena AT, Rojas AS, Eckert GJ, Stewart KT. The effects of
varying alcohol concentrations commonly found in mouth rinses on the force decay of
elastomeric chain. Angle Orthod 2012; 82(5):894-899.
2. Ferriter JP, Meyers CE, Lorton L. The effect of hydrogen ion concentration on the forcedegradation rate of orthodontic polyurethane chain elastics. Am J Orthod 1990; 98:404-410.
3. Nattrass C, Ireland AJ, Sherriff M. The effect of environmental factors on elastomeric chain and
nickel titanium coil springs. Eur J Ortho 1998; 20:169-176.
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4. Matheus Melo Pithona et.al. Do mouthwashes with and without bleaching agents degrade the
force of elastomeric chains? Angle Orthod. 2013; 83:712–717.
5.
Khudair A Al-Jumaili et al. Evaluation and comparison of the effect of artificial saliva and
mouthwash solution on force degradation of different types of orthodontic traction
aids(comparative in vitro) Al–Rafidain Dent J. 2011; 11(1):52-62.
6. Al-Kassar. S. The Force Degradation of Elastic Chain in Different Environments and for
Different Intervals (An In Vitro Study). Al–Rafidain Dent J. 2011; 11(2):231-237.
9.
SIGNATURE OF CANDIDATE
10. REMARKS OF THE GUIDE
SATISFACTORY
DR. RADHAKRISHNAN GOGINENI
11. 11.1 NAME AND DESIGNATION OF
PROFESSOR
GUIDE
DEPARTMENT OF
ORTHODONTICS
(IN BLOCK LETTERS)
DENTOFACIAL ORTHOPAEDICS
AND
P.M.N.M DENTAL COLLEGE AND HOSPITAL
BAGALKOT.
11.2 SIGNATURE
11.3 CO-GUIDE (IF ANY)
11.4 SIGNATURE
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11.5 HEAD OF THE
DEPARTMENT
DR. RADHAKRISHNAN GOGINENI
PROFESSOR
DEPARTMENT OF
ORTHODONTICS
AND
DENTOFACIAL ORTHOPAEDICS
P.M.N.M DENTAL COLLEGE AND HOSPITAL
BAGALKOT.
11.6 SIGNATURE
12. 12.1 REMARKS OF THE
PRINCIPAL
12.2 SIGNATURE
DR. S.S. VANAKI
PRINCIPAL
P.M.N.M DENTAL COLLEGE AND HOSPITAL
BAGALKOT.
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