The benefits of glass ionomer self-adhesive materials in restorative dentistry

Bonded, resin-based composite restorative materials have potential advantages. If the dentin bond achieved is not greater than the polymerization stress, loss of retention is likely, resulting in areas of microleakage and postoperative sensitivity. Class 5 lesions restored with no preparation have been used for testing the clinical performance of new adhesive restorative systems. Laboratory studies have demonstrated that bond strength varies according to the depth of dentin and the degree of calcification. Until the later generations of dentin bonding agents, retention rates for bonded, resin-based composites were typically more erratic and lower than glass ionomer (GI) and resin-modified glass ionomer (RMGI) restorative materials. Providing stress relief during setting is inherent in GI and RMGI materials, which helps to explain their good retention rates, despite their low bond strengths. GI and RMGI liners and lightly filled resin bonding agents provide similar stress relief. Current evidence supports the use of both RMGI and composite restorations placed with a liner of lightly filled resin in adhesive Class 5 restorations. Bonded, resin-based composite has the advantage of finishing to a high-gloss surface, making it more acceptable in areas of the mouth that are highly visible.     

Aesthetic resin onlay restorations: 'rationale and methods'

Resin composite restorations have gained increasing popularity over the past two decades. This has been largely driven by a patient-orientated demand for the use of aesthetic restorative materials. It has occurred concomitantly with an improvement in the mechanical properties of available materials, and advances in our knowledge of resin bonding. Onlay restorations are advocated for a plethora of clinical applications. This paper considers the role of adhesive onlay restorations fabricated in resin composite in contemporary restorative practice, including the presentation of two case reports. Clinical Relevance: This case report describes a minimally invasive, aesthetic solution to provide cuspal coverage by means of either a direct or indirect resin composite onlay restoration, respectively.     

Amalgam--Resurrection and redemption. Part 1: the clinical and legal mythology of anti-amalgam.

Dental amalgam has come under attack for its allegedly poor physical properties and clinical performance in addition to its poor appearance. It has been claimed that the American Dental Association has a hidden agenda to protect amalgam and that other countries have banned its use. A literature search revealed that the vast majority of amalgam restorations do not cause fractured cusps or have recurrent caries. Most amalgam restorations have been shown to last longer than resin composite restorations. In addition, the materials and techniques involved in amalgam restorations have vastly improved in recent years. Like resin composite restorations, amalgam restorations can often be repaired. The American Dental Association has no vested interest in protecting amalgam. The use of amalgam has not been banned in any country in the European Union. According to the latest scientific information available, dental amalgam is a remarkably durable and long-lasting restorative material. Although its appearance is unesthetic, its clinical performance and effectiveness are unsurpassed by those of resin composite.     

Assuring restorative integrity in extensive posterior resin composite restorations: pushing the envelope.

Clinicians are increasingly being called on to satisfy the restorative demands of patients who request tooth-colored restorations but are unable to afford an optimum indirect restorative option. Consequently, in clinical practice, the limits of the direct posterior resin composite technique are being stretched. There is a need for techniques that will satisfy the complex variables of clinical practice and allow for successful utilization of posterior resin composite in large cavity preparations. The objective of this article is to explain the rationale behind the materials and techniques involved in the delivery of these complicated restorations.     

Critical appraisal. Class II composite resin restorations with gingival margins in dentin

The rising demand for esthetic restorations has considerably increased the number of direct composite restorations being placed in private practices. While composite resin is often selected primarily for its esthetic qualities, another significant advantage of direct composite restorations is the ability to perform conservative cavity preparations. The traditional configuration used for amalgam restorations is no longer mandatory; thus, more sound tooth structure can be preserved.
The technique of composite placement is complex when compared to amalgam placement. The use of adhesive systems prior to placement of composite restorations requires not only excellent isolation to avoid contamination, but also precise manipulation of the adhesive system. While stable bonds to enamel are routinely obtained, the heterogeneous composition and intricate morphology of dentin makes this substrate more challenging to restore. In addition, the cavity configuration (C-factor) and inherent polymerization shrinkage of composite resin play an important role in the durability of the composite–dentin interface. Class II preparations often have gingival margins in root surfaces because of the location of the caries lesion. Clinicians are then faced with a preparation that is challenging to isolate, has a relatively high C-factor, and relies on optimal bonding to dentin to secure long-lasting marginal integrity. Various restorative techniques, such as incremental placement or the use of an intermediate layer (flowable composite or resin-modified glass ionomer cements—open sandwich technique), have been some of the methods proposed to increase the longevity of composite restorations, especially those with margins in dentin. This review evaluates some of the published research on Class II composite resin restorations with margins in the dentin/cementum.     

Microleakage of several class V anterior restorative materials: a laboratory study.

The study was designed to evaluate the marginal leakage of abraded gingival areas in extracted teeth using five anterior composite resin acid-etch restorative materials and a glass ionomer cement, ASPA. In using three of the composite resin restorative materials, Simulate, Cervident, and Concise, there was a layer of unfilled resin between the etched tooth surface and the composite resin. Restodent and Enamelite were placed directly on the etched tooth surface. The results of the study indicate that there is a significantly greater degree of marginal leakage at the gingival margin than there is at the occlusal or incisal margin of composite restorations. In addition, greater marginal leakage was observed in those restorations where no layer of unfilled resin was placed between the etched tooth surface and the composite resin. The glass ionomer cement showed no marginal leakage at intervals of one day, three months, and six months; however, a small amount of leakage was observed at the incisal or occlusal and gingival margins at a year on half of the autoradiographs. A study has been initiated to determine leakage patterns around composite resin restorations placed in teeth with naturally occurring cervical erosion or abrasion.     

The amalgam-free dental school

OBJECTIVES: To review the change in teaching of Restorative Dentistry at Nijmegen dental school over the period 1986 to the present. KEY POINTS: In 1986, class I and II resin composite restorations were included in the pre-clinical program. However, these courses still started with class I and II amalgam restorations. From 1990 on, the number of amalgam restorations placed in the clinic gradually decreased while the number of resin composite restorations increased. Meanwhile, resin composite had become the first choice for treatment of primary caries (class I and class II) lesions. Finally in 1994, the pre-clinical training started with resin composite restorations before dental amalgam was taught and the advantage of a minimal preparation was further emphasized. Since 2001 the teaching of dental amalgam ceased at the dental school. This was not an abrupt change but the result of a long transitional stage during which it was gradually substituted by resin composite. This step-by-step introduction allowed the acceptance of composite resin by the staff as an alternative for dental amalgam in posterior restorations. As in 2001 students placed only 2.5 amalgam restorations before graduation, it was decided to stop with the pre-clinical training program. CONCLUSIONS: The introduction of resin composites meant an important change in teaching restorative dentistry at Nijmegen dental school. It was not just a change in materials and techniques but also a change in treatment philosophy. The reduced need for preparation and the strengthening effect on the remaining tooth were the principal reasons for the shift from dental amalgam to adhesive dentistry with resin composite at Nijmegen dental school.     

Direct composite resin restorations in posterior teeth

Direct adhesive composite resin restorations are being used extensively. A proper understanding of the technique and its indications has contributed to the widespread use of this restorative approach. Recent industrial developments brought novel technologies to dentistry including the introduction of nanofillers to the restorative procedures. This article reviews some features of this new type of composite resin, discusses its advantages over other materials, and presents an application technique for restoration of posterior teeth through a clinical case report.     

A comparison of various adhesive composite restorations in the posterior regions.

The evolution of adhesive materials has revolutionized posterior restorative techniques, contributing to the progressive abandonment of traditional metallic materials. The considerable progress in the field of adhesive dentistry and composite resin technology, together with patients' increasing aesthetic demands, are radically modifying the modern conservative approach to the restoration of the posterior regions. This article will discuss the indications and fundamental stages of three posterior restoration techniques using composite materials. LEARNING OBJECTIVES: This article discusses the indications for posterior composite restorations and outlines the procedures followed to ensure aesthetic results. Upon reading this article, the reader should: 1) Understand the variety of conservative composite options the clinician can utilize to meet a patient's aesthetic and biological expectations. 2) Become familiar with the indications for using different composite treatment plans and materials.     

Longevity of new hybrid restorative materials in class III cavities

The aim of this study was to evaluate the durability of two new tooth-colored restorative materials, a polyacid-modified resin composite (compomer) and a resin-modified glass ionomer cement. In an intra-individual comparison with a resin composite, the materials were studied during a 5-yr period. In 50 patients, 154 large class III restorations were placed. Most patients received one of each of the three materials. The restorations were evaluated by modified United States Public Health Service (USPHS) criteria. Of the 144 restorations evaluated, 15 were found unacceptable. No significant differences were seen between the materials concerning recurrent caries incidence. The resin composite showed a significantly better color match. No difference was found between resin composite fillings in enamel- or total-etched cavities. Significantly higher surface roughness was found in the aged resin-modified glass ionomer cement restorations. Fracture of the incisal enamel corner was observed adjacent to 10 restorations. None of the three total-etch techniques resulted in postoperative sensitivity or loss of vitality. All the restorative techniques showed a low failure rate during the 5-yr follow-up.     

Composite or amalgam? Not a black or white decision

Amalgam as a restorative material in dentistry is discussed because of believed toxic properties of the material, yet there is no scientific prove for the assumption. Adhesive restorations are a possible alternative for amalgam in restoring posterior teeth. For treatment of primary caries, the direct composite resin restoration has many advantages. When greater defects are to be restored, adhesive composite resin restorations become less favourable. At this moment no long term results are available for indirect adhesive techniques. For the time being it seems necessary to use composite resin as well as amalgam for the restoration of posterior teeth.     

Adhesion and tooth-colored restoratives.

Research aimed at developing durable adhesion between esthetic restorative materials and tooth surfaces has been progressing for over 35 years. Inherent deficiencies in many esthetic materials have directed research toward new adhesive agents and modifications in application techniques. Overcoming these deficiencies has been difficult and many questions remain despite encouraging developments. A new generation of resin dentin-bonding agents has surfaced and may further adhesive efforts with modern composite resins. The glass-ionomer cement continues to establish itself as a valuable adhesive direct restorative material. Recent advances in glass-ionomer technology have given rise to new lining materials that may also complement composite resin behavior. The use of dentin conditioners or pretreatments has been explored and may enhance the adhesion of esthetic restoratives as well. Finally, a better understanding of application techniques and of the tooth surface itself may offer new insights into developing more stable adhesion with esthetic restorative materials.     

Restoring the incisal edge

Restorative dentistry evolves with each development of new material and innovative technique. Selection of improved restorative materials that simulate the physical properties and other characteristics of natural teeth, in combination with restorative techniques such as the proximal adaptation and incremental layering, provide the framework that ensures the optimal development of an esthetic restoration. These advanced placement techniques offer benefits such as enhanced chromatic integration, polychromatism, ideal anatomical form and function, optimal proximal contact, improved marginal integrity and longer lasting directly placed composite restorations. The purpose of this article is to give the reader a better understanding of the complex restorative challenge in achieving true harmonization of the primary parameters in esthetics (that is, color, shape and texture) represented by the replacement of a single anterior tooth. The case presented demonstrates the restoration of a Class IV fracture integrating basic adhesive principles with these placement techniques and a recently developed nanoparticle hybrid composite resin system (Premise, Kerr/Sybron, Orange, CA). The clinical presentation describes preoperative considerations, tooth preparation, development of the body layer, internal characterization with tints, development of the artificial enamel layer, shaping and contouring, and polishing of a Class IV composite restoration. The clinical significance is that anterior tooth fractures can be predictably restored using contemporary small particle hybrid composite resin systems with the aforementioned restorative techniques. These placement techniques when used with proper attention to preparation design, adhesive protocol and finishing and polishing procedures, allow the clinician to successfully restore form, function and esthetics to the single anterior tooth replacement.     

A nonmechanical etiology: The adhesive design concept.

Advances in restorative material formulations and adhesive technology have expanded and created new treatment possibilities for dental practitioners. Due to this evolution, composite resins are being used with increasing frequency in posterior restorations. In order to successfully place these restorations, the clinician must understand the rationale for restorative material selection, preparation design, adhesive protocol, and composite resin placement. This article illustrates these considerations for placing a Class I posterior composite restoration.     

A 7-year randomized prospective study of a one-step self-etching adhesive in non-carious cervical lesions. The effect of curing modes and restorative material

Objective

The aim of this study was to evaluate the clinical retention of a one-step self-etching adhesive system (Xeno III) in Class V non-carious cervical lesions and the effect of restorative material and curing techniques on longevity of the restorations.

Materials and methods

A total of 139 Class V restorations were placed with the self-etching primer Xeno III and a resin composite (Tetric Ceram) or a poly-acid modified resin composite (Dyract AP) in non-carious cervical lesions without intentional enamel involvement. The materials were cured with a conventional continuous light, a soft-start or a pulse-delay curing mode. The restorations were evaluated at baseline, 6, 12, 18 and 24 months and then yearly during a 7 year follow-up with modified USPHS criteria. Dentine bonding efficiency was determined by the percentage of lost restorations.

Results

During the 7 years, 135 restorations could be evaluated. No post-operative sensitivity was reported by the participants. Overall relative cumulative loss rate frequencies for the adhesive system at 6 and 18 months and 7 years, independent of curing technique and restorative material, were 0.8%, 6.9% and 23.0%, respectively. The self-etching adhesive fulfilled at 18 months the full acceptance ADA criteria. Tetric Ceram showed at 7 years a 20.9% loss of retention and Dyract AP a 25.0% loss rate (Log rank p = 0.48). The loss rates for the 3 curing techniques: continuous, soft start and pulse delay were 17%, 27.9% and 24.4%, respectively (Log rank p = 0.52). No secondary caries was observed.

Significance

The single-step self-etching adhesive showed acceptable clinical long-time retention rates to dentine surfaces independent of restorative material and curing technique used.     

5-year clinical performance of resin composite versus resin modified glass ionomer restorative system in non-carious cervical lesions

AIM: To comparatively assess the 5-year clinical performance of a 1-bottle adhesive and resin composite system with a resin-modified glass ionomer restorative in non-carious cervical lesions. METHOD AND MATERIALS: One operator placed 70 restorations (35 resin modified glass ionomer restorations and 35 resin composite restorations) in 30 patients under rubber dam isolation without mechanical preparation. The restorations were directly assessed by 2 independent examiners, using modified USPHS criteria at baseline and 6, 12, 24 and 60 months. RESULTS: Twenty-two patients were available for recall after 5 years (73.3% recall rate) and 55 out of 70 restorations were evaluated. Excellent agreement was registered for all criteria between examiners (kappa > or = 0.85). Sixteen composite restorations were dislodged (51.5% retention) and 1 ionomer restoration was lost (96.4% retention). The McNemar test detected significant differences in resin composite restorations between baseline and 5-year recall for marginal integrity (p<0.001) and retention (p=0.004). For resin modified glass ionomer restorations, no significant differences were identified for all criteria (p>0.05). When comparing both materials, the Fisher exact test pointed out significant differences in retention (p=0.002) after 5 years of clinical service. CONCLUSIONS: After 5 years of evaluation, the clinical performance of resin modified glass ionomer restorations was superior to resin composite restorations.     

Long-term deterioration of composite resin and amalgam restorations.

Previous long-term longitudinal studies of two different methods of placing an auto-cured conventional anterior composite resin, and of a low- and a high-copper amalgam alloy, had shown similar restoration survivals despite the different resin treatment methods used or the types of amalgam alloy placed. Therefore, the aim of the present study was to assess several clinical factors or characteristics of these restorations that were believed to affect the survival of the restorative materials. The 950 composite resin and the 1042 amalgam restorations examined were placed by many operators in numerous patients attending a dental hospital. The composite resin restorations were placed using unetched- and etched-enamel-bonding treatment methods, and the amalgam restorations were polished after insertion. Clinical ratings supplemented by color transparencies were used for the assessment of four factors for the resin, and four factors for the amalgam restoration. Significant deterioration differences were found for several of the clinical factors assessed for both the two different composite resin treatment methods, and for the two different amalgam alloys, which were not directly related to the restoration survivals.     

Treatment of localized anterior tooth wear with a glass-fiber-reinforced composite resin: a clinical report

Developments in adhesive dentistry have provided the dental profession with new restorative materials and technology to restore esthetics and function to the worn anterior dentition. This clinical report describes treatment of localized anterior tooth wear with fiber-reinforced composite resin restorations as an alternative treatment method.     

Postoperative dental bleaching: effect of microleakage on Class V tooth colored restorative materials

The effect of 3 percent, 11 percent, and 16 percent carbamide peroxide bleaching solutions and 35 percent hydrogen peroxide bleaching gel on microleakage of Class V composite resins, resin modified glass ionomer cements, and compomer restorative materials together with corresponding (if indicated) fourth/fifth generation bonding agents was evaluated using previously extracted human teeth. Five groups of Class V cavity preparations were placed in enamel of the facial surfaces of 200 teeth. Groups A through D included 40 restorations each (4 different restorative materials and their accompanying bonding agent multiplied by 10 teeth) treated with 3 percent, 11 percent, and 16 percent carbamide peroxide bleach and 35 percent hydrogen peroxide bleach. Group E included 40 restorations without treatment of bleach and stood as the control. The restorative materials included were: Fuji II LC resin modified glass ionomer cement, Helioprogress composite resin/-Heliobond adhesive system, Aelitefil composite resin/Allbond 2 adhesive and Dyract compomer material/Prime & Bond adhesive system. Bleaching agents included were Rembrandt 3 percent peroxide gel, Perfecta 16 percent carbamide peroxide gel, White & Brite 11 percent carbamide peroxide solution and Superoxyl 35 percent hydrogen peroxide gel. All teeth were thermally stressed for 100 cycles and microleakage were assessed by dye penetration. The results were tabulated using Analysis of Variance (ANOVA) testing procedures. The Aelitefil composite resin material behaved the least favorably (relative to microleakage) compared to the other materials when exposed to various concentrations of dental bleaching agents.     

A review of polymerization shrinkage stress: current techniques for posterior direct resin restorations

In general excellent results cannot be guaranteed when using resin-based composites for posterior restorations. This is due to polymerization shrinkage which can still be regarded as the primary negative characteristic of composite resins. A review of available literature regarding the polymerization process, its flaws, and suggested strategies to avoid shrinkage stress was conducted. Several factors responsible for the polymerization process may negatively affect the integrity of the tooth-restoration complex. There is no straightforward way of handling adhesive restorative materials that can guarantee the reliability of a restoration. At present, the practitioner has to coexist with the problem of polymerization shrinkage and destructive shrinkage stress. However, evolving improvements associated with resin-based composite materials, dental adhesives, filling, and light curing techniques have improved the predictability of such restorations. This critical review paper is meant to be a useful contribution to the recognition and understanding of problems related to polymerization shrinkage and to provide clinicians with the opportunity to improve the quality of composite resin restorations.