RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES, KARNATAKA, BANGALORE

ANNEXURE-II

PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION

1 NAME OF THE CANDIDATE Dr. Anita Karwa

Post Graduate Student, ADDRESS Department of Prosthodontics, V.S. Dental College and Hospital, K. R. Road, V. V. Puram, Bangalore – 560 004. 2 NAME OF THE INSTITUTE: V.S.Dental college and hospital.

3 COURSE OF STUDY AND Master of Dental Surgery in Prosthodontics. SUBJECT :

4 DATE OF ADMISSION TO 02.05.2008 THE COURSE:

5 TITLE OF THE TOPIC: Evaluation of the marginal fit of ceramic veneers made from three different materials- An in vitro study

BRIEF RESUME OF THE INTENDED WORK: INTRODUCTION: Ceramic veneers have traditionally been made from aluminous or reinforced feldspathic porcelains, which have relatively poor strength in themselves but produce a strong structure when bonded to enamel. That the strength of traditional porcelain is generally adequate for anterior porcelain veneers is supported by a number of clinical studies (1). The evolution of ceramic veneers began with free-formed feldspathic glass. The current trend is to use pressable, leucite-modified feldspathic ceramics (2), and the machinable ceramics using CAD/CAM technology (3), for ceramic veneers. Pressable ceramics score over feldspathic veneers in terms of strength, while imparting the desired esthetics. Machinable ceramics offer us the restorations of highest strength and the ease of fabrication.

NEED FOR THE STUDY: Considering that the tooth preparation for a ceramic veneer has a much larger margin than that for complete veneer crowns, the marginal fit of these restorations assumes greater importance in determining the prognosis of the restoration. Hence, the present study is being undertaken to determine the marginal fit of veneers made using feldspathic porcelain, pressable ceramics, and machinable ceramics.

REVIEW OF LITERATURE: Harasani MH, Isidor F, Kaaber S (1999) conducted a study to compare the marginal adaptation of indirect composite and porcelain veneers in vitro using transmitted-light microscope. Ten extracted molars were prepared for veneers after which five composite veneers and five porcelain veneers were made. The composite and porcelain veneers, in general, demonstrated a similar absolute marginal discrepancy and thickness of luting agent with average values from 50 microns to 195 microns. (4) John A Sorensen, Judith M Strutz, Sean P Avera, Daniel Materdomini (1992) evaluated the marginal fidelity and microleakage of porcelain veneers made with the platinum foil and refractory die techniques. Twenty extracted maxillary central incisors were used and assigned to two groups: group 1- for platinum foil technique and group 2– for refractory die technique. The platinum foil veneers had significantly better vertical marginal fidelity but significantly more overcontouring than had the refractory die veneers. (5)

Danielle Layton, Terry Walton (2007) carried out a 16- year prospective study of 304 porcelain veneers. According to the results of their study, when bonded to enamel substrate, feldspathic veneers offer a predictable long-term restoration with low failure rate. The cumulative survival rate was 96 % ± 1 % at 5 to 6 years, 93 % ± 2 % at 10 to 11 years, 91 % ± 3 % at 12 to 13 years, and 73 % ± 16 % at 15 to 16 years. (2)

Li R, Jiang T, Wang YN, Li SQ, Cheng XR (2007) carried out a study comparing marginal fit of porcelain laminate veneers and veneers made using CAD/CAM technology. 65 CAD/CAM veneers were made for 23 patients and 105 porcelain veneers were made for 25 patients. There was no significant difference between feldspathic and CAD/CAM veneers in color match, marginal discoloration and marginal fit. (6)

N.Ozturk, B. Ozturk, M.A. Malkoc, S.T.Tasdemir (2008) evaluated the marginal fit of laminate veneers manufactured with IPS e.max and Cerec 3 system .48 extracted maxillary central incisors were prepared for veneers and were randomly divided into two ceramic systems - IPS e.max and Cerec 3.There was no significant difference between two different ceramic laminate systems (p<0.05). The fit of IPS E. Max and Cerec 3 laminate veneers showed the similar range of gap width. (7) OBJECTIVES OF STUDY:

1) To assess the marginal fit of ceramic veneers made using feldspathic porcelain. 2) To assess the marginal fit of ceramic veneers made using pressable ceramics. 3) To assess the marginal fit of ceramic veneers made using machinable ceramics, fabricated using computer aided design-computer aided manufacture (CAD/CAM) technology.

MATERIALS AND METHODS:

SOURCE OF DATA:

Fifteen recently extracted sound, non carious permanent maxillary central incisors will be used for the study.

METHOD OF COLLECTION OF DATA: SAMPLE SIZE: Fifteen (15) veneers of each type of ceramic material will be fabricated. Thus, total number of specimens is 15x3 = 45, that is, forty-five.

STUDY MATERIAL: Fifteen recently extracted sound,non carious permanent maxillary central incisors Polyvinyl siloxane impression material Refractory material (Nori-Vest) Die stone (Type IV dental stone) Feldspathic porcelain (Noritake Super Porcelain EX-3) Pressable ceramic material ( IPS Empress, Ivoclar Vivadent) Machinable ceramic (Cerec, Sirona), using CAD/CAM technology Stereomicroscope, to measure the marginal discrepancy

STUDY METHOD: Fifteen recently extracted, sound, non carious permanent maxillary central incisors will be prepared for ceramic veneers following standard preparation protocol. Impressions of the prepared teeth will be made using polyvinyl siloxane, and will be casted to produce three dies for each impression: one using refractory material, for feldspathic porcelain veneer and two using die stone, for pressable ceramic and machinable ceramic veneers. This will be done for all fifteen prepared incisors. Using the refractory dies and the stone dies; fifteen ceramic veneers, each of feldspathic porcelain, pressable ceramics, and Signature of the Candidate:

Remarks of the Guide:

Name and Designation of the Guide:

DR. SATISH BABU Signature: Professor and Head, Department of Prosthodontics, V.S. Dental College and Hospital, Bangalore – 560 004

Head of the Department:

DR. SATISH BABU Signature:

Remarks of the Chairman and Principal: Signature: