Dentistry Commons^™

Porcelain Fused To Metal (Pfm) Crowns And Caries In Adjacent Teeth, Durr-E-Sadaf, Zubair Ahmad

Zubair Ahmad

OBJECTIVE: To assess the discrepancies in marginal integrity and contact points of Porcelain Fused to Metal (PFM) crowns and its association with caries in adjacent teeth. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: Dental Section of the Aga Khan University Hospital, Karachi, from January to August 2009. METHODOLOGY: Ninety six (96) patients with PFM crowns on maxillary and mandibular premolars and molars were included in this study. Single unit PFM crowns that were part of fixed bridge with at least one natural adjacent tooth were studied. PFM crown with no adjacent tooth or badly broken down teeth were …

Alumina Ceramic For Dental Applications: A Review Article., Ahmed A. Madfa

Ahmed A. Madfa

Alumina has received considerable attention and has been historically wellaccepted as biomaterials for dental and medical applications. This article reviews the applications of this material in dentistry. It presents a brief history, dental applications and methods for improving the mechanical properties of aluminabased materials. It also offers perspectives on recent research aimed at the further development of alumina for clinical uses, at their evaluation and selection, and very importantly, their clinical performance. This article also stated about the Functionally Graded Materials (FGMs) which has been conceived as a new material design approach to improve performance compared to traditional homogeneous and …

Use Of Zirconia In Dentistry: An Overview., Ahmed A. Madfa

Ahmed A. Madfa

Due to an increasing interest in esthetics and concerns about toxic and allergic reactions to certain alloys, zirconia was proposed as a new ceramic material in the later part of 20th century. It has become a popular alternative to alumina as biomaterial and is being used in dental applications for fabricating endodontic posts, crown and bridge restorations and implant abutments. It has also been applied for the fabrication of esthetic orthodontic brackets. This article presents a brief history, dental applications and new methods for fabrication of zirconia improving its mechanical properties. Additionally, the bonding between zirconia and resin cements as …

Application Of Calcium Phosphate Materials In Dentistry, Ahmed A. Madfa

Ahmed A. Madfa

Calcium phosphate materials are similar to bone in composition and in having bioactive and osteoconductive properties. Calcium phosphate materials in different forms, as cements, composites, and coatings, are used in many medical and dental applications. This paper reviews the applications of these materials in dentistry. It presents a brief history, dental applications, and methods for improving their mechanical properties. Notable research is highlighted regarding (1) application of calcium phosphate into various fields in dentistry; (2) improving mechanical properties of calcium phosphate; (3) biomimetic process and functionally graded materials. This paper deals with most common types of the calcium phosphate materials …

Morphology And Fracture Of Enamel, Sangwon Myoung, James Lee, Paul Constantino, Peter Lucas, Herzl Chai, Brian Law

Paul J. Constantino

This study examines the inter-relation between enamel morphology and crack resistance by sectioning extracted human molars after loading to fracture. Cracks appear to initiate from tufts, hypocalcified defects at the enamel–dentin junction, and grow longitudinally around the enamel coat to produce failure. Microindentation corner cracks placed next to the tufts in the sections deflect along the tuft interfaces and occasionally penetrate into the adjacent enamel. Although they constitute weak interfaces, the tufts are nevertheless filled with organic matter, and appear to be stabilized against easy extension by self-healing, as well as by mutual stress-shielding and decussation, accounting at least in …

Microtensile Bond Strength Of Self-Adhesive Resin-Based Dental Cement, Selda Keskin

This study investigated the effectiveness of bleaching agents on the micro tensile bond strength (mTBS) of self-adhesive luting cement and enamel. A total of 126 samples were prepared from the labial surfaces of permanent human maxillary central incisors and assigned into three groups with 42 samples each as: control, enamel bleached with 10% hydrogen peroxide (HP), and enamel bleached with 10% carbamide peroxide (CP). Rely X Unicem1 (3 M, ESPE) was used as self-adhesive resin cement. The total testing period for bleaching was selected as 14 days and the bleaching agents were applied 8 hours a day. The statistical one-way …

Microstructural Characteristics Of Functionally Graded Materials Designed As Dental Post, Ahmed A. Madfa

Ahmed A. Madfa

To study the interfaces and microstructure of multilayered materials fabricated based on functionally graded concept for use as dental posts.

New Generation Of The Dental Posts For Endodontic Application., Ahmed A. Madfa

Ahmed A. Madfa

Fabricated multilayer dental post with the functionally graded design is a novel product that exhibits graded properties varied from coronal to apical parts of the tooth. The new dental post definitely performs better than posts available in the market and improves the quality of human life

Effects Of Different Denture Cleansers On The Tensile Bond Strength Of Denture Liners, Selda Keskin

The effect of two denture cleansers (Polident1 and Protefix1) on the tensile bond strength between four soft liner materials (Molloplast B1, Permaflex1, Sofreliner Tough Medium1, and GC Reline Soft1) and a conventional denture base resin was investigated. For each of the liner materials 35 test specimens were prepared according to test the requirements and assigned into seven groups (n¼5). Before tensile testing, five of the liner specimens were kept in water or soaked in two cleansing solutions during 2 and 7 d. Five other samples served as a control group subjected directly to tensile testing. The bond strength values were …

Tensile Bond Strength Of A Highly Cross-Linked Denture Tooth To The, Selda Keskin

This study compared tensile bond strengths between conventional compressionmolded heat (HC)-, auto (AP)-, and microwave-polymerized (MC) poly(methyl methacrylate)-based denture resins and a relatively new injection-molded, microwave-polymerized polyurethane based resin (MI) bonded to a highly cross-linked denture tooth. In the first part of the experiments, denture teeth were used as received. In the second part, they were treated with dichloromethane to see its effect on bonding of conventional denture bases (HCS and APS). Bond strength was tested in tension according to ADA specification No.15. The results showed that the HC group failed cohesively because of higher interface bonding (49.95 MPa) compared …

The Evaluation Of Some Flexural Properties Of Denture Base Resin Reinforced With Various Aesthetic Fibers, Selda Keskin

No abstract provided.

Evaluation Of Laser Treatment On Reline-Base Composites, Selda Keskin

No abstract provided.

Bond Strength Of A Silicone Soft Lining Material To Pol(Methyl Methacrylate) Resin Treated With Maleic Anhydride And Its Terpolymers, Selda Keskin

No abstract provided.

The Effect Of Esthetic Fibers On Impact Resistance Of A Conventional Heat-Cured Denture Base Resin, Selda Keskin

No abstract provided.

Flexural And Bonding Properties Of A Denture Base Polymer Treated With Nitric Acid Or Ultraviolet Radiation Before Relining With Molloplast-B, Selda Keskin

No abstract provided.

The Effects Of Some Methacrylate Monomers Used As Liquid Component On Tensile And Flexural Strengths Of A Poly (Methyl Methacrylate) Denture Base Resin., Selda Keskin

No abstract provided.