Low Shrinkage Silorane Composites.

Polymerization shrinkage of methacrylate composites utilizing bisphenol-A glycidal methacylate or urethane dimethacrylate has typically been about 3-3.5% by volume. Though adjustments have been made to filler loading, filler size, filler particle distribution, and improved silanization, the polymerization contraction still creates some significant clinical problems. A new composite utilizing a completely different chemistry has been released, with polymerization shrinkage of less than one percent. This article will review the clinical effects of polymerization contraction of composite resins, the nature and properties of this chemical form of composite, and potential clinical applications.

Repair Versus Replacement of Restorations.

Dentists evaluate previously placed restorations every day to determine their acceptability. Many restorations have some defects associated with them. This article will review criteria useful to determine whether a restoration can be repaired, refurbished, or replaced. Methods and materials usefulfor repair will be discussed, as well as the science behind the decision-making.

Amalgam Restorations: To Bond or Not.

This article will review the use of various liners used to eliminate microleakage in amalgam restorations. It will review the literature about whether amalgam restorations are improved by using a bonding process and if so specifically how it improves the patient outcome.

Using Multiple Bonding Strategies.

There are many ways to bond to tooth structure, some micro-mechanical some chemical, some a combination. Different dentin bonding materials have different bonding strengths to differently prepared surfaces, and because of differences in their nature, different areas of tooth structure present peculiar bonding challenges. This paper will review a variety of material types, elucidating their particular bonding strengths and commenting on improved bonding strategies to increase durability, strength, and favorable pulpal response. In this discussion, resin dentin bonding systems, glass ionomers, Gluma, resin cements, and newer combined products will br reviewed.

The effect of occlusal forces on restorations.

This review will focus on the effect occlusal forces, both normal masticatory force and paranormal bruxing and clenching force, have on various restorative materials and their interaction with the teeth through a variety of bonding mechanisms. Salient physical properties of each of the materials will be reviewed, as well as the effect occlusal force has on restoration durability.

Enamel craze lines.

Enamel craze lines are a common clinical finding, especially in older patients and in patients who brux. These craze lines frequently are discolored and may present as clear in color, grey, or brown. The clinical question is, when do enamel craze lines need restoration and when should we leave them untreated? This review will look at enamel structure and the effects of occlusion, bruxing, temperature, and restorations on enamel structure. Recommendations will be made on how and when to deal with these cosmetic defects of enamel.

Prevention of dental disease versus surgical treatment.

The members of the Minnesota legislature have debated methods by which access to dental care and treatment of dental disease can be improved at a cost lower than that of present delivery systems. This review sheds light on some significant aspects of what the dental profession has learned over the last century that has proven significantly beneficial to the overall health of the American populace. Recommendations are made in the use of cost-effective dental public health interventions that could be used to provide better access and improved dental health at lower cost.

Clinical uses of glutaraldehyde/2-hydroxyethylmethacrylate (GLUMA).

Glutaraldehyde/2-Hydroxyethylmethacrylate (GLUMA) is a chemical frequenty used for desensitization of teeth and has other uses as suggested in the literature. Some newer recommendations have been made relative to its use during tooth preparation, as a disinfectant, rewetting during bonding, prior to cementation of crowns and bridges, and in dealing with pulpal exposures. This article will explore the science behind these and other applications for this chemical and its effect on the tooth structure and its local environment.

Cementation: methods and materials. Part two.

This is a review of the literature of the last 21 years about cementing or luting indirect restorations to tooth structure. Recommendations are made as to the surface preparation of precious metals, non-precious metals, indirect composite materials, and all available porcelain materials including feldspathic, luecite reinforced, lithium di-silicate, slip cast aluminum oxide, densely sintered aluminum oxide, and zirconia prior to luting. Using data from a variety of sources, product categories of materials and various bonding materials and procedures are ranked according to their bond strength and durability.

Extension for prevention: margin placement.

This article will review the concept of extension for prevention popularized by G.V. Black around the early 1900s. Concepts of extension and prevention have changed over the years with a more informed knowledge of the caries process, improved materials, cutting instruments, and techniques. The reasons for placement of the outline form relative to the tooth morphology, gingival tissue, relationship to adjacent teeth, and the choice of material will be described for all of the materials used in restorative dentistry. Research will be cited to support the scientific basis for outline form placement.

The clinical significance of marginal fit.

Clinical evaluation of restoration acceptability includes marginal adaptation, restoration and preservation of anatomic form, color match, cavosurface discoloration, and presence of marginal caries. This paper will review what is known about marginal fit of all materials relative to their acceptable fit. Some explanation will be given of how material properties affect marginal fit, what the expected longevity of different materials is relative to marginal fit, and how marginal fit affects development of secondary or marginal caries. Marginal fit is assumed to affect restoration longevity by either encouraging or discouraging microleakage and development of secondary or marginal caries. Marginal fit and its effect on the health of the gingival tissues have been reviewed in an earlier paper on polishing and will not be reviewed here. Is there some correlation between marginal fit of the various materials used in restorative dentistry and this assumption? This paper will review the literature found on Medline and present the science behind the clinical significance of marginal fit utilizing in vitro studies where necessary and in vivo studies whenever possible. Numerous authors replicating these studies are used to improve reliability and replicability.

The effect of occlusal forces on restorations.

This review will focus on the effect occlusal forces, both normal masticatory force and paranormal bruxing and clenching force, have on various restorative materials and their interaction with the teeth through a variety of bonding mechanisms. Salient physical properties of each of the materials will be reviewed, as well as the effect occlusal force has on restoration durability.

Why do we polish? Part one.

What does polishing oral hard tissues and restorations accomplish? The two parts of this review will describe the effect of polishing on various restorative materials and teeth; the development of biofilm and adherence of plaque to teeth and restorations; the effects of unpolished versus polished surfaces on gingival health and longevity of restoration; and techniques for polishing various restorative materials. A listing of available polishing materials is included in Part Two, which will appear in the July-August Northwest Dentistry.

Causes and treatment of root resorption.

This article will review what is known about the classification, causes, and treatment of root resorptions that are either internal or external.

Tooth wear: when to treat, why, and how. Part One.

Tooth wear has been described in the literature as physiologic--that is, normal, expected over the life span of an individual, and not creating a pathologic condition. It has also been described in pathologic terms as caused by stress, corrosion, and friction, utilizing a variety of mechanisms and affected by a host of endogenous and exogenous factors. From a clinician's point of view, when should we decide to restore a tooth or change the conditions in the mouth to protect the teeth; and what should we consider using to either prevent or restore abnormal--i.e., pathologic--tooth wear? This review in Part One will look at what is normal, non-pathologic tooth wear and etiologies associated with all forms of tooth wear. Part Two will discuss the effects of tooth wear in enamel and dentin, when it may be advisable to intervene in the wear processes diagnosed on specific patients, and what methods of prevention and restoration can be utilized to restore or maintain the dentition. This review will not look at the need for full mouth reconstruction due to wear.