Bioactive Bulk Composite Satisfies Esthetic Demands While Protecting Against Restoration Failure

The recent development of "bioactive" restoratives represents a significant advance in dental materials. The basic benefit of these restorative materials is that they serve as a mechanism by which calcium is released creating a precipitate of hydroxyapatite on the material's surface. A number of bioactive restoratives are now available, which include not only direct restorative materials, but also bioactive liners and cements. Typically, the placement of these bioactive restorative materials must be done in a specific manner, per the manufacturer's technical instructions; techniques vary by products. This article presents a case study that outlines the specific technique for the placement of one such bioactive restorative material that releases calcium, phosphate, and fluoride to stimulate mineral apatite formation and remineralization at the material-tooth interface.

What Is in Your Zirconia?

The immense popularity of zirconia as an indirect restorative material in dentistry has led to seemingly countless numbers of companies selling zirconia discs and blocks. The reliability of zirconia, however, is subject to specific manufacturing and processing protocols. Thus, it is of paramount importance for any dental professional utilizing zirconia to be aware of the source of the material and the various factors that can affect the success or failure of a final restoration. This article discusses the journey of zirconia, from being found among the elements of the earth to being placed in the patient's mouth. It also touches on drawbacks, such as translucency, associated with zirconia.

A Simple Technique for Fabricating a Screw-Retained/Cemented Implant-Supported Crown.

Many factors figure into the long-term success of an implant-supported restoration. While some are uncontrollable, others are manageable. The cement-retained implant-supported restoration is easier to fabricate, while the screw-retained implant-supported restoration involves more complicated, timeconsuming laboratory procedures. Most research has found the screw-retained restoration has had more minimal complications than the cement-retained counterpart. This article describes a simple, low-cost technique of converting a cement-retained implant crown to a screw-retained implant crown, which allows for easy retrievability and eliminates a number of laboratory steps and costs.

Classifying dental ceramics: numerous materials and formulations available for indirect restorations.

Because there are numerous ceramic systems available to clinicians for all types of indirect restorations, deciding which system works best for a given clinical situation can be a challenge. Understanding the different classifications of ceramic restoratives can be helpful not only to the clinician but also the dental technician. Manufacturers are constantly introducing newer ceramic materials and improving their existing systems, which has resulted in an increase in all-ceramic restorations and fewer porcelain-to-metal restorations. The classification of ceramic materials remains mostly constant; however, it is subject to change based on newer materials and formulations. The classifications of ceramics are described using several different methods.

Provisional material considerations: creating a blueprint of the final restorations.

Indirect restorative dentistry generally requires temporization of prepared teeth during the laboratory fabrication phase. Over the years, the physical properties of newer provisional materials have improved, which has enabled an expansion of the function of provisional restorations. Better strength, surface finish, and color match have increased their acceptability by patients and clinicians. In some clinical situations provisional restorations can provide information that is critical to the overall success of a case. Such information allows the clinician to verify and confirm with the patient the esthetics, phonetics, and function of the proposed anterior restorative treatment. The provisional restorations can also provide valuable information to the laboratory technician regarding design, contour, length, shade, and even correct articulation of the master model. The success of the definitive restoration is dependent on the accurate transfer of this information to the laboratory technician.

Creating super dentin: using flowable composites as luting agents to help prevent secondary caries.

As dental material science and technology rapidly evolve and enable dentists to render more efficient treatment, an old challenge persists--preventing the formation of secondary caries at the restorative margin. Research has indicated that the existence of an acid-base resistant zone (ABRZ), which forms between the adhesive layer and the tooth, may have a preventive effect. The ABRZ is also known as super dentin, and the thickness of this zone is material dependent. Functional monomers such as 10-methacryloyloxyethyl dihydrogen phosphate and materials such as flowable composites used as luting agents may play roles in formation of the ABRZ. This article also includes a case study to illustrate the author's technique in helping to create the ABRZ.

Adhesive dentistry: the development of immediate dentin sealing/selective etching bonding technique.

A major objective of dental research over the past 60 years has been a search for the "dream-team" of dental adhesives. In fact, a recent Medline search produced more than 6,500 papers on dentin bonding and its techniques. Adhesive systems are designed to retain direct and indirect restorations, minimize leakage at the margin, and be simple to place while producing consistent results. The development of materials and techniques has an interesting history; some have recirculated from the past and are being used in some form today. Buonocore used the etchant phosphoric acid at the beginning of the adhesive revolution. Though not accepted for many years it eventually became the "gold standard" for etching enamel. Technique sensitivity moved it out of favor and, through the development of self-etching acidic primers, was eliminated from some adhesive systems. Although these primers may have successfully addressed postoperative sensitivity, adhesion was compromised. The bond strength of these systems has now been improved with the incorporation of phosphoric acid-etch to condition enamel prior to using the adhesive system. This article will trace the history of adhesive techniques and materials and how it has led to the creation of a new technique that combines two bonding methods.

Ceramics.

For more than 30 years, Compendium has provided its readers with university-based continuing education and editorial, demonstrating the latest advances in clinical procedures and techniques. Using the same peer-reviewed format and influence/direction from Compendium's distinguished editorial board, Special Report provides insight on the latest advances in product technologies and the resulting benefits to both you and your patients. A discussion by the author on new clinical/laboratory research and product development strategies, as well as what the results could mean for dental treatment, also is included. Focusing on one product category per issue provides a detailed review of the category and a comprehensive resource to help guide your treatment planning process.

Press-to-zirconia: a case study utilizing cad/cam technology and the wax injection method.

Computer technology is increasingly becoming an effective tool in restorative dentistry. Whether chairside or laboratory-fabricated, computer-aided design/ computer-aided manufacturing (CAD/CAM) engineering has become widely accepted in the fabrication of dental restorations. Zirconia has been successfully used in medical therapy and is now considered a viable alternative to metal as a substrate in single- and multiple-unit fixed restorations. Proper tooth preparation and handling of this material is essential for a successful outcome. This presentation will discuss how CAD/CAM systems can utilize zirconia frameworks to provide treatment of a maxillary anterior restoration.