RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES

BANGALORE, KARNATAKA

PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION

1. / NAME OF THE CANDIDATE AND ADDRESS (in block letters) / DR. VICTORY AHANTHEM
DEPARTMENT OF PROSTHODONTICS, CROWN AND BRIDGE INCLUDING IMPLANTOLOGY,
DR. SYAMALA REDDY DENTAL COLLEGE, HOSPITAL & RESEARCH CENTRE,
MARATHAHALLI, BANGALORE- 560037
2. / NAME OF THE INSTITUTION / DR. SYAMALA REDDY DENTAL COLLEGE, HOSPITAL & RESEARCH CENTRE,
MARATHAHALLI, BANGALORE- 560037
3. / COURSE OF STUDY AND SUBJECT / MASTER OF DENTAL SURGERY IN PROSTHODONTICS, CROWN AND BRIDGE INCLUDING IMPLANTOLOGY
4. / DATE OF ADMISSION TO THE COURSE / 17/06/2013
5. / TITLE OF THE TOPIC / An in-vitro study to compare the shear bond strength of an esthetic acrylic teeth to heat cure denture base resin and injection moulded denture base resin.
6. / BRIEF RESUME OF INTENDED WORK:
6.1 Need for the study:
·  In the practice of esthetic dentistry, achievement of a natural and convincing result produces an immediate acceptance by the patient.
·  The failure of the bond between acrylic resin teeth and denture base resin materials remains a considerable problem.
·  Previous research has indicated that the introduction of a bonding agent to the tooth–resin interface significantly increased the tensile bond strength.
·  To further investigate without the bonding agent ,a study of shear bond strength assessment needs to be carried out .
·  Hence, this study is to be conducted to evaluate the shear bond strength of acrylic teeth with different denture base resin thereby evaluating the survival of fracture under highest possible loading
6.2  Review of literature.
1)  In vitro study conducted by J. L. Cunningham et al, to evaluate the shear bond strength of resin teeth to heat-cured and light-cured denture base resin. For heat-cured resin, bonding agents were applied to the ridge lap area of the teeth to be tested and a reaction time was allowed prior to the introduction of the resin. As for light-curing resin Triad VLC bonding agent was applied. Shear loading was applied by a loading rod and the force required to shear the denture base resin off the tooth was recorded. The result showed that the bonding agent did produce an improvement in bonding, more significantly so in case of light cure denture base resin.
2)  In vitro study conducted by Takahashi et al,the study examined the bond strength between 2 types of denture teeth and 3denture base resins. Conventional denture teeth and cross-linked denture teeth were bonded to either a heat-cured denture base resin, a microwave-cured denture base resin, or a pour-type denture base resin. Compressive load was applied at 45 degrees on the palatal surface of each tooth until fracture. The result shows conventional resin teeth possessed higher bond strength than cross-linked denture teeth.The heat-cured denture base resin significantly surpassed the microwave-cured denture base resin in bond strength.
3)  In vitro study conducted by Amarnath G S et al, Bond strength and tensile strength of surface treated resin teeth with microwave cured and heat cured acrylic resin denture resin. Ridge lap surface areas of the acrylic maxillary anterior teeth were treated with sandblasting and grinding procedure. Specimens were fabricated and processed with conventional heat cured, microwave cured and self cured techniques. Specimens were subjected to bond strength and tensile strength testing. The result shows sandblasting in all type of curing possessed higher bond and tensile strength. Grinding method yielded higher bond and tensile strength compared to control groups
4)  In vitro study conducted by Lagouvardos et al, study was to investigate the strength of the composite resin–denture tooth bond as affected by different tooth surface treatments. Spectrum TPH was condensed on 112 mandibular first molar acrylic resin and composite resin denture teeth. Four groups were treated with Prime & Bond NT adhesive, and three groups were treated with One Step adhesive.Four groups (two of each adhesive category) were treated with Composite Activator and air abrasion. In one group, AeliteFlo was used .Bond strength was done by a Monsanto testing machine. The results were evaluated statistically with two-way ANOVA and the Scheffé method. Results show bondstrength of composite resin was greater to composite than to acrylic resin teeth when thebond was mediated only with adhesives. One Step adhesive and AeliteFlo resulted in ahigher bond of composite resin to both types of teeth. Wetting tooth surfaces withComposite Activator did not increase the bond strength.
5)  In vitro study conducted by Schneider et al, study was to compare the tensile bond strengths of heat- and microwave polymerized acrylic resins among 4 types of acrylic resin denture teeth. Heat-polymerized (Lucitone 199) and microwave-polymerized (Acron MC) acrylic resins were used. Four types of acrylic resin denture teeth were milled to a fixed diameter according to ADA specification no. 15. Ten specimens of each tooth type were processed to each of the denture base materials . Ten additional resin control specimens without teeth also were fabricated. Specimens were thermocycled and tested for strength until fracture. Data were analyzed with analysis of variance and Duncan’s multiple range test.Results show the mean force required to fracture the specimens ranged from 5.3 ±3.01 to 21.6± 5.2 MPa for the microwave-polymerized base and 11.2 ± 3.0 to 39.1± 5.1 MPa for the heat-polymerized base.The heat-polymerized groups failed cohesively within the denture base resin or the tooth, and microwave-polymerized groups failed adhesively at either the ridge lap or occlusal surface of the denture teeth.
6)  In vitro study conducted by Barpal et al, study evaluating the failure load of acrylic resin teeth bonded to 2 high impact acrylic resins. The ridge lap portion on 120 identical denture teeth were modified with 3 variables:(1) placing a diatoric, (2) using monomer to prewet the denture tooth, and (3) breaking the glaze.Variables were combined to form 6 groups of 10 teeth each, and processed with Lucitone 199 (Lucitone)or SR-Ivocap (Ivocap) acrylic resin. Data analysis included the use of a heterogeneous variance linear regression model.Results show for Lucitone 199 acrylic resin,the highest failure loads resulted when the ridge lap was left with an intact glaze and did not have a diatoric,with no significant influence from the use of monomer
6.3Aims and Objective Of The Study
The purpose of this study is to evaluate the Shear bond strength of acrylic teeth to Heat-Cured Denture Base Resin and Injection Molded Denture Base Resin
MATERIALS AND METHODS
7.1 Source of Data:
MATERIALS.
1. Acrylic resin anterior teeth
2. Heat cured arylic denture base resin material
3.Injection moulding denture base resin material
EQUIPMENTS:
1.  Dental plaster
2.  Rubber bowls
3.  Spatulas
4.  Flasks
5.  Clamps
6.  Injection System Unit
7.  Separating Solvent
8.  Mould
9.  Mould Storage
10.  Wax knife
11.  Universal testing machine
7.2 Method of collection of data(including sampling procedure, if any):
1.  20 Central incisors (non worn teeth) with uniform and comparable width and height will be selected .
2.  20 central incisors teeth was waxed onto the surface of a rectangular wax block.
3.  The samples are embedded in a wax block
4.  10 samples were polymerized using heat cured technique
5.  10 samples were polymerized using injection moulding technique
6.  The force was applied with a universal testing machine
7.  Biostatistical analysis is than carried out for finding the significance of the comparative study
7.3 Does the study require any investigation or intervention to be conducted on patients or other Humans or Animals? If so, please describe briefly..
. -No
7.

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8. / List of references:
1)  HahnP, Gustav M, Hellwig E:An in-vitro assessment of the strength and porcelain veneers dependent on tooth preparation.The Journal of Oral Rehabilitation 2000 ;27: 1024-1029.
2)  Abd-El Ghani M, Salem E: Fracture strength and microleakage of laminate veneers. Cairo dental journal 2009;25(2);245-254.
3)  Serdar H, Mine D, Berran O: The effect of various preparation designs on the survival rate of porcelain laminate veneers. The journal of adhesive dentistry 2009;11(5);405-411.
4)  Matthew C, Sebeena M, Karthik K: A review on ceramic laminate veneers. Journal of Indian academy of dental specialist 2010;1(4);33-37.
5)  Ashish S, Anjali K, Shubhlashini N et al: Survival of porcelain laminate restorations based on different incisal preparation designs: An Analysis. Journal of conservative dentistry 2011;14(1);10-15.
6)  Kyle K, Yada C, Keith M et al: Influence of the preparation design and existing condition of tooth structure on load to failure of ceramic laminate veneers. The Journal of Prosthetic Dentistry 2011;105(6): 374-382.
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9. / Signature of the candidate: / DR. VICTORY AHANTHEM
10. / Remarks of guide:
11. / Name and designation of: (in block letters)
11.1 Guide: / PROF.DR. RUPALI KAMATH
HEAD OF DEPARTMENT
DEPARTMENT OF PROSTHODONTICS, CROWN AND BRIDGE INCLUDING IMPLANTOLOGY,
DR SYAMALA REDDY DENTAL COLLEGE, HOSPITAL AND RESEARCH CENTRE, BANGALORE-37
11.2 Signature:
11.3 Co- guide (if any):
11.4 Signature:
11.5 Head of department / DR. RUPALI KAMATH
PROFESSOR AND HEAD , DEPARTMENT OF POSTHODONTICS, CROWN AND BRIDGE INCLUDING IMPLANTOLOGY ,
DR SYAMALA REDDY DENTAL COLLEGE, HOSPITAL AND RESEARCH CENTRE, BANGALORE-37
11.6 Signature
12. / 12.1 Remarks of the Chairman and Principal
12.2 Signature: