الفهرس | Only 14 pages are availabe for public view |
Abstract The marginal fit is a crucial aspect for fixed restorations because large marginal opening allows more plaque accumulation, gingival sulcular fluid flow, and bone loss resulting in microleakage, recurrent caries and periodontal disease compromising the longevity of the restoration. Many studies have been carried out evaluating the marginal discrepancies of single restorations fabricated using different systems and materials. The present investigation was designed to study the effect of two different porcelain veneer materials - the LUMINEERS and the IPS Empress pressable porcelain veneers and “the prep.” and “the No prep technique” - on the marginal accuracy of the final restorations. A total of 15 human maxillary upper central incisors mounted in epoxy resin blocks were constructed to represent the samples. The samples were divided into three groups of five samples each and group one and two represented the “prep. ” group while the third group represented the “No-prep” group. Group one “pressable IPS Empress Esthetic veneers”: Teeth in this group received 0.5mm window preparation design for porcelain laminate veneers. Group two “LUMINEERS prep.” Teeth in this group received 0.5mm window preparation design for porcelain laminate veneers Group three “LUMINEERS no-prep”: Teeth in this group received No preparation at all to represent the “NO prep” technique. After preparation a poly-vinylsiloxane impression was taken for all the samples, poured, Porcelain veneers were constructed then each veneer cemented to its respective tooth with a dual-cured resin cement material by the aid of a specially designed and constructed cementing device. Then the samples were evaluated for marginal accuracy using a scanning electron microscope to assess the horizontal marginal gap width at six predetermined positions on each surface of the tooth. A total of 18 measurements per veneer were recorded. Data were collected, tabulated and statistically analyzed. In the present study the marginal accuracy results after being statistically analyzed revealed that the highest mean marginal gap was obtained by the “No prep LUMINEERS” group (78.56µm) followed by the “IPS Empress Esthetic” group (55.39µm) while the “LUMINEERS prep.” group showed the lowest mean marginal gap (47.28µm). The SEM results matched the statistical results showing the least marginal gap width with the “LUMINEERS prep. Group” followed by “IPS Empress Esthetic group”, then the “LUMINEERS no-prep “exhibiting variable highest gap measurements |