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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.” 1 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. 2 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 3 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. 4 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 5 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 6 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. 7 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. 8 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 9 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. 10