SYNOPSIS

Dr.ARJUN N MITHRA

POST GRADUATE STUDENT

DEPARTMENT OF PROSTHODONTICS

K.V.G.DENTAL COLLEGE & HOSPITAL,

KURUNJIBAG-SULLIA (DK)

KARNATAKA, INDIA

Rajiv Gandhi University of Health Sciences, Karnataka

Bangalore

ANNEXURE-II:PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION

1. / NAME OF THE CANDIDATE AND ADDRESS (IN BLOCK LETTERS) / Dr. ARJUN N MITHRA
POST GRADUATE STUDENT,
DEPARTMENT OF PROSTHODONTICS
K.V.G.DENTAL COLLEGE & HOSPITAL,
KURUNJIBAG-SULLIA(DK)
KARNATAKA,INDIA-574 327
2. / NAME OF THE INSTITUTION / K.V.G.DENTAL COLLEGE & HOSPITAL,
KURUNJIBAG-SULLIA(DK)
KARNATAKA,INDIA-574 327
3. / COURSE OF STUDY AND SUBJECT / MASTER OF DENTAL SURGERY
PROSTHODONTICS INCLUDING CROWN & BRIDGE
4. / DATE OF ADMISSION OF COURSE / 27TH MAY2011
5. / TITLE OF THE TOPIC: / AN IN-VITRO STUDY TO COMPARE THE DIMENSIONAL STABILITY AND SURFACE HARDNESS OF THREE ELASTOMERIC BITE REGISTRATION MATERIALS AT VARIOUS TIME INTERVALS
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8. / BRIEF RESUME OF THE INTENDED WORK
6.1 NEED FOR THE STUDY :
Precise articulation of a patient’s casts is a prerequisite for proper diagnosis and subsequent correct treatment. Apart from the operator’s clinical ability and the technique followed, the chosen material can critically affect the accuracy of the interocclusal registration.1
During the reconstruction of a patient’s occlusion, a centric relation interocclusalrecord is used to orient the mandibular cast to the maxillary cast in anarticulator.2
Considerable controversy exists regarding the accuracy, usefulness, and manipulative skills required in obtaining accurate interocclusal records.3
The accuracy of an interocclusal record, however is influenced not only by the material properties , but also by the recording technique as well as the reliability of the mandibular position influenced by occlusal contact, muscular action or tissue changes within the joint.4
The introduction of polyether and polyvinylsiloxaneinterocclusalrecording media has made clinician unsure which material they should use. These elastomeric materials are chemically similar to the impression materials that have been used successfully for many years. Modifications have been made by adding plasticizers and catalyst to provide different handling characteristics; however, it remains unknown whether these modifications in the parent impression materials have altered their excellent accuracy and dimensional stability properties. Delayed articulation of the patient casts can occur for various reasons. Therefore, the dimensional stability of interocclusal recording material over time is of utmost importance, as it ensures a more accurate representation of the patient’s maxillomandibular relationship.1
The aim of this in vitro study is to compare dimensional stability and surface hardness of polyetherand two types ofaddition siliconebite registration material at 1, 24, 48 and 72h time interval.
6.2 REVIEW OF LITERATURE
An experimental study done to evaluate the linear dimensional change and accompanying weight change of several elastomeric interocclusal recording materials. One polyether and 4 polyvinylsiloxaneinterocclusal recording material were tested in comparison with a wax and zinc oxide eugenol paste for linear and weight changes at 0, 1, 24, 48 and 72hrs in a controlled laboratory environment. It was concluded that polyether presented the smallest linear change at all time intervals. Addition reaction silicones presented statistically significant difference in recordings of linear changes among them only at the 1st and the 24thhour.1
Another in-vitro study on evaluation of dimensional stability, accuracy and surface hardness of interocclusal recording materials at various time intervals. Polyvinyl siloxane, zinc oxide eugenol and aluwax were taken in the study and checked for accuracy, dimensional stability and surface hardness at 1, 24,48 and 72 hrs. Concluded that dimensional stability, accuracy and surface hardness of three interocclusal recording materials are influenced by time factor and polyvinylsiloxane was more dimensionally stable when compared to zinc oxide eugenol and aluwax and had a highest surface hardness.6
An in-vitro study on Differential accuracy of silicone-body interocclusal records and associated weight loss due to volatiles. Study was done using 3 different brand (Optosil, Unitek Corporation, Monrovia; Citricon, Kerr manufacturing Company, Romulus, Mich; Imput, Vicon Products Corp., Mamaroneck, N. Y.) silicone bite registration materials. Concluded that the three materials displayed weight losses over times which were generally proportional to their respective dimensionalchanges.7
6.3 OBJECTIVES OF THE STUDY
  1. To evaluate the dimensional stability of no-1 and no-2 addition silicone bite registration material at 1, 24 ,48 and 72 hours
  1. To evaluate the dimensional stability of polyether bite registration material at 1, 24 ,48 and 72 hours
  1. To compare the dimensional stability of no-1, no-2 addition silicone and polyether bite registration material at 1, 24 ,48 and 72 hours
  1. To evaluate the surface hardness of no-1 and no-2addition silicone bite registration material at 1, 24 ,48 and 72 hours
  1. To evaluate the surface hardness of polyether bite registration material at 1, 24 ,48 and 72 hours
  1. To compare the surface hardness of no-1, no-2 addition silicone and polyether bite registration material at 1, 24 ,48 and 72 hours
MATERIAL & METHODS.
7.1 Instruments and materials used during the course of the study-
Instruments:
  1. Stainless steel diestandardized according to ADA specification no 19
  2. 4 × 4 inch square glass slab
  3. 500 g weight
  4. Elastomeric Auto mixing gun
  5. Bard Parker blade no 15
  6. Glass slab
  7. Stainless steel mixing spatula
Materials:
  1. Addition silicone bite registration material (ImprintTM bite) no-1
  2. Addition silicone bite registration material (Futar)no-2
  3. Poly ether bite registration material (Ramitec)
Equipment:
  1. Travelling microscope
  2. Shore hardness tester
  3. Water bath
7.2 METHODOLOGY.
Preparation of stainless steel die
In this study a stainless steel die will be prepared according to the ANSI/ADA specifications no 19. Die will consist of ruled block and mold. Ruled blockwill have height 31mm,diameter of inner ring 30mm, diameter of outer ring 38mm,distance between vertical lines 25mm and distance between two horizontal lines 2.5mm which will be scored with 3 horizontal and 2 vertical lines,will be used for impression making.The horizontal lines will be labeled 1,2 and 3.The width of the horizontal lines will be 0.02mm.Two cross-points at the intersection of the vertical lines with line 2 will be marked x and x’ and will serve as the beginning and end points of measurements for dimensional accuracy.Mold will have 38mm outer ring diameter, 30mm inner ring diameter and 6mm height.8
A total 30 samples with 10 each from 3 different materials will be made.
All samples will be stored at room temperature (250C)
Method of collection of data:
Each sample will be measured for dimensional stability and surface hardness at 1, 24, 48 and 72 hrs.
Dimensional stability will be measured by measuring the distance between the reference lines at 4 fixed points on the sample. The mean of the distance between reference lines in each sample will be compared with the corresponding measurement on the standard stainless steel die under travelling microscope.
Surface hardness will be measured using same samples with shore hardness tester.
Four readings will be taken on four different sites of the sample and mean value will be taken for statistical analysis.
STATISTICAL ANALYSIS
The study will be analyzed through:-
1One-way ANOVA test
2Tukey HSD - Honesty test
7.3 Does the study require any investigations or interventions to be conducted on patients or other humans or animals?
No
7.4 Has the ethical clearance been obtained from your institution in case of 7.3?
Yes
LIST OF REFERENCES
  1. Konstantion X. Michalakis, ArgirisPissiotis, VassilikiAnastasiadou, DanaiKapari. An experimental study on particular physical properties of severalinterocclusal recording media. Part 2: linear dimensional change and accompanying weight change. J prosthodont 2004; 13:150-159.
  1. Harry C. Lundeen. Centric relation record: the effect of muscle action J. Prosthet. Dent. March, 1974; 31(3):244-253.
  1. Philip L. Millstein, Joseph H. Kronman, R. Ernest Clark. Determination of the accuracy of wax interocclusal registrations J. Prosth Dent February, 1971; 25(2):189-196.
  1. Muhamad Ghazal, Matthias Kern. Mounting casts on an articulator using interocclusal records. J prosthet dent 2008; 100:408-409.
  1. Jose Luis Vivas, MarianellaSierraalta. Interocclusal record fabricated with bis-acrylic composite resin and vinyl polysiloxane registration material. J prosthet dent 2009; 102:199-200.
  1. Anup.G, Ahila.S.C, Kumar M.Vasantha. Evaluation of dimensional stability, accuracy and surface hardness of interocclusal recording materials: an invitro study. J Indian prosthodontics socjan-mar 2011; 11(1):26-31.
  1. Philip L. Millstein, R. Ernest Clark, Richard L. Myerson. Differential accuracy of silicone-body interocclusal records and associated weight loss due to volatiles. J prosthet dent 1975; 33(6):649-654.
  1. Reportsof councils and bureaus.JADA.April 1977;94:733-741

9. / SIGNATURE OF CANDIDATE:
10. / REMARK OF GUIDE:
11. / NAME & DESIGNATION OF
11.1 GUIDE: / PROF(DR.) PRANAV MODY
11.2 SIGNATURE:
11.3 CO- GUIDE:
11.4 SIGNATURE:
11.5 HEAD OF DEPARTMENT: / PROF(DR) PRANAV MODY
PROFESSOR AND HEAD OF THEDEPARTMENT
11.6 SIGNATURE:
12. / 12.1 REMARK OF THE PRINCIPAL:
12.2 NAME: / PROF(DR) MOKSHA NAYAK
12.3SIGNATURE: