An effective technique for extended proximal contacts in composite resin restorations

Obtaining a firm anatomic contact has been a difficult criteria in placing Class II posterior composite restorations. Various techniques have been developed and a number of products marketed to accomplish this task, but none have combined the necessary qualifications of ease, simplicity, and effectiveness for consistent and predictable results. To address this challenge, two innovative devices--a precontoured (biplanar concave) sectional matrix band and a light--focusing tip-have been developed. Using a clinical case presentation, this article describes the application of these devices to obtain high quality proximal contacts, even in widely separated teeth. The learning objective of this article is to familiarize clinicians with this procedure. The technique is simple and universally applicable with a variety of posterior composite materials and placement methods.     

Marginal integrity and postoperative sensitivity in Class 2 resin composite restorations in vivo

INTRODUCTION: Problems that may arise in resin composite Class 2 restorations include microleakage and postoperative sensitivity. However, limited in-vivo research is conducted to evaluate these processes. AIM: The aim of this study was to assess postoperative sensitivity, microleakage and the pooling of adhesives in relation to Class 2 box-type composite restorations placed in vivo using various adhesive systems and application techniques. MATERIALS AND METHODS: One hundred and forty-four Class 2 box restorations were placed in the mesial and distal surfaces of 72 premolar teeth in-vivo using one of three combinations of adhesive systems and three filling techniques. After 6 weeks of clinical service postoperative sensitivity was recorded. The teeth were then extracted, immersed in a dye solution and sectioned. Microleakage and pooling of the adhesive was recorded. Statistical analysis involved logistic regression and chi2 tests to identify differences between groups at p < 0.05. RESULTS: Of the 144 restorations, 65 showed minimal cervical leakage in enamel, 5 suffered leakage into dentin and 74 were free of microleakage. No statistically significant differences were found in cervical microleakage between the adhesive systems or between filling procedures. Occlusal microleakage in the enamel was present in 16 of the 160 restorations. Liner Bond 2 restorations leaked significantly more at the occlusal surface (p < 0.05). Pooling of the adhesive was significantly less when PhotoBond was used. No spontaneous postoperative sensitivity was reported. Twenty-eight restorations were sensitive to loading. Postoperative sensitivity was significantly less in patients with Liner Bond 2 restorations. CONCLUSIONS: The adhesive systems used in this study showed minimal leakage into dentin in vivo. Using Liner Bond 2, restorations exhibited more occlusal leakage but were significantly less sensitive to loading.     

Posterior composite resin restorations: operative innovations

The adhesive revolution is alleviating reservations regarding posterior composite resin restorations, established by past experience with outdated materials and techniques. Improved materials, instrumentation, and placement techniques have enhanced the performance of current formulations of posterior composite resins over their predecessors. However, it is a clinician's operative skill that ultimately determines the quality of a restorative option. The learning objective of this article is to share the author's experience in attaining adhesive excellence with posterior tooth-colored restorations as well as aesthetic anatomic form, minimal postoperative sensitivity, and a bond which can weather the true test of success-durability. Optimal applications, dental dam requirement, importance of the first increment of composite resin, restitution of occlusal morphology, and the clinical application are discussed.     

Treatment considerations for posterior laboratory-fabricated composite resin restorations

A variety of techniques are currently available to restore dentition in the posterior region, and the selection of the proper modality is dependent upon evaluation and satisfaction of numerous criteria. Direct materials provide limited strength in the posterior segment, and full-coverage indirect techniques (e.g., crown restorations) often require the destruction of sound tooth structure. When proper case selection, preparation design, and clinical protocols are utilized, a laboratory-processed composite resin (belleGlass, Kerr/Sybron, Orange, CA) can provide an optimal means by which to successfully restore posterior dentition without compromising the existing tooth structure.     

Contraction gaps in Class II restorations with self-cured and light-cured resin composites

PURPOSE: To evaluate in vitro the cervical gap formation in composite restorations in which an increment of autopolymerizing composite was interposed between the light-cured filling material and the dentin bonding system. Two different self-cured materials and two different adhesives were used and compared. MATERIALS AND METHODS: In 40 Class II cavity preparations with the gingival margins in dentin or cementum, an increment of either of two different autopolymerizing composites, Palfique or Bisfil 2B, was interposed between the light-cured filling material (Palfique Estelite) and either of two different dentin bonding systems, All-Bond and Superbond D (20 restorations each). The specimens were immersed in toluidine blue dye. A section was taken from each specimen and examined under an optical microscope. The extent of dye penetration was measured. The specimens were then stored in water for 1-4 months and replicas of the sections were examined by SEM. RESULTS: Good marginal adaptation was observed for All-Bond/Bisfil 2B in all the restorations. All-Bond/Palfique showed good adaptation in 7 out of 10 cases, the failures occurring between bonding agent and composite. Superbond D/Palfique and Superbond D/Bisfil 2B showed marginal gap formation in 8 out of 10 and in all the restorations respectively. In the latter, four gaps occurred between bonding agent and dentin. As a consequence, a very significant difference (P<0.001) was found between All-Bond and Superbond treatments; no significant difference was found between Bisfil 2B and Palfique in each group treated with either All-Bond or Superbond. After 1-4 months storage in water, hygroscopic expansion of the restorative materials reduced the total number of gaps and the efficacy of the treatments was no more significantly different.     

Direct composite resin restorations of the anterior single tooth: clinical implications and practical applications

Modern technology has continued to improve composite resins to the point where they are commonly used in restorative dentistry. In spite of some drawbacks, such as polymerization shrinkage, incomplete conversion and cross-linking, and undesirable water sorption, the expected time of service of these restorations is extended continuously due to physical and chemical improvements. The improved handling and excellent optical properties of the latest generation of composite resins can provide the appearance of natural dentition. Sophisticated effects can be obtained through the use of direct intraoral applications of stratification techniques. This article discusses common indications for direct restoration of anterior teeth and their treatment in order to be biocompatible with the adjacent hard and soft tissues and to meet the requirements of form, function, and phonetics.     

Erosion resistance of composite Ag’MCaF2 contacts

The erosion resistance of composite Ag’MCaF₂ contacts in the communitation of constant currents I=1–10 A was studied. With the aid of metallographic analysis it was shown that in comparison with cast silver contacts, composite contacts even at I=1 A show a stronger tendency to change the direction of mass transport, which increases with increase of the current to I≤4 A. In this range of commutation currents there is a small loss of material, accompanied by the removal of a considerable part of Ag’MCaF₂ particles from the working zone to the periphery of the contacts, which promotes their improvement. The laws revealed in the work allowed us to recommend the composite Ag’MCaF₂ contacts for use in relay technology. Tests in microswitches confirmed the high erosion resistance of composite contacts in the range I=1–3 A.     

Two-year clinical evaluation of preventive resin restorations

Structural and morphologic changes in peripheral blood neutrophilic leukocytes were examined with the aim to diagnose and predict the clinical course of acute pyoinflammatory maxillofacial diseases. Classification of structural and morphologic signs of neutrophilic leukocyte activation levels during odontogenic pyoinflammatory diseases were studied using optic and electron microscopy. There degrees of neutrophilic leukocyte activation were distinguished: inactive, moderately active, and hyperactive. Inactive cells occurred in normal subjects and patients with mild forms of the disease, moderately active ones in patients with mild and medium-severe condition, hyperactive ones in those with medium-severe and grave disease. Increased count of hyperactive neutrophilic leukocytes in the peripheral blood was a sign predicting a grave clinical course of the disease with complications.     

In vitro evaluation of marginal and internal adaptation of class II resin composite restorations after thermal and occlusal stressing

The aim of this in vitro trial was to evaluate the external and internal adaptation of class II composite restorations to tooth structure by means of replica scanning electron microscope (SEM) observation. Standard MOD preparations were cut in human extracted teeth with margins located above and below the cementoenamel junction. Cavities were restored with either a direct multilayered technique, inlays (using conventional or dual DBA application) or prepolymerized composite inserts, using similar restorative material (Syntac, Variolink and Tetric). Evaluations were performed after mechanical and thermocycling. For the marginal adaptation in enamel, the bevelled margins of the direct group resulted in higher percentages of "continuity" (92.5% mesially and 94.6% distally), while the "marginal tooth fracture" was the most commonly found defect in groups with a butt preparation (up to 29.4%, with inserts). For the marginal adaptation in dentin, "continuity" percentages varied from 59% (inlay) to 87.9% (insert). As regards the internal adaptation, results for the whole dentin interface varied from 43.1% (inlay) to 63.9% (inlay with dual bonding) of "continuity". No regional difference in internal adaptation was found between the different preparation areas, except between gingival dentin and gingival enamel (44.9% vs. 80.7% of continuity, all group pooled data). Debonding occurred only at the dentin-restoration interface and consistently took place at the top of the hybrid layer. In the present experimental conditions, the inlay or insert techniques, which make use of the Dual bonding concept, proved to have the best potential to maintain the integrity of dentin-restoration interface.     

An in-vitro investigation of microleakage and gap size of glass ionomer/composite resin "sandwich" restorations in primary teeth

Eighty extracted primary molars were divided into four groups of twenty teeth. Class II cavities were prepared in all teeth with equal numbers of proximal boxes having cavosurface margins either in enamel, or dentin/cementum. Each group was allocated to an open or closed sandwich technique using glass ionomer as a lining. Following the placement of the composite resin restorations, the gap size measured at the proximal box was greatest for the closed sandwich group with the cavosurface margin on enamel (0.203 microns) or dentin/cementum (0.174 microns). Microleakage scores were measured at the proximal box and were greatest for the closed sandwich group with the cavosurface margin on dentin/cementum. The best result was obtained for the open sandwich group with the cavosurface margin on enamel.     

Microleakage of cervical restorations using two resin bonding systems

OBJECTIVES: To determine whether coins located in different portions of the esophagus differ in their likelihood of spontaneous clearance, and to determine the frequency of asymptomaticity among children with esophageal coins. DESIGN: Retrospective case review. SETTING: Pediatric academic tertiary care center. PATIENTS: All 73 children presenting in an 18-month period to a pediatric emergency department for coin ingestion whose roentgenographic evaluation revealed an esophageal coin. INTERVENTIONS: None. OUTCOME MEASURES: Hospital records of all children were reviewed for demographic information, coin denominations, esophageal locations of ingested coins based on roentgenographic reports, performance of invasive removal procedures, and the presence or absence of signs and/or symptoms. RESULTS: All of the 58 children with proximal or middle esophageal coins underwent invasive removal procedures, while nine (60%) of 15 distal esophageal coins passed into the stomach spontaneously (P < .001). Five children (7%) were asymptomatic. CONCLUSIONS: Proximal and middle esophageal coins should be promptly removed, as per present practice. Children with distal esophageal coins should be observed up to 24 hours before an invasive removal procedure, since many will spontaneously clear their coins. Since esophageal coins may be asymptomatic, all children who have swallowed coins should undergo roentgenographic evaluation.     

Chairside-fabricated indirect resin restorations: a new articulated technique

A case report of a chairside-fabricated indirect resin composite restoration is used to introduce a modification to a newly released one-appointment resin inlay-onlay technique. Fast-setting poly(vinyl siloxane) die material accommodates an articulated working cast within 10 minutes. The technique allows the economical construction of large, occlusal, load-bearing, extracoronal resin composite restorations. The guarded prognosis associated with extensive posterior resin composite restorations is acknowledged; nevertheless this technique remains a realistic option for those financially compromised patients who request tooth-colored restorations.     

Tunnel restorations. A 3 1/2-year follow up study of Class I and II tunnel restorations in permanent and primary teeth

During 1988-89, 224 patients with approximal caries in the premolar/molar regions were provided with 318 tunnel restorations. In case of perforation of the enamel in the enamel/dentin border, (23%), complete Class II-tunnel restorations with glass ionomer cement and composite resin were made. In case of "intact" enamel, (77%), partial Class I-tunnel restorations were made. The restorations were controlled at annual routine recalls and the success rate after 3 1/2 years was 74% for permanent teeth, and 10% for primary teeth. Restorations in permanent teeth, made during the second year of the study were successful in 82%, as compared with 62% for restorations made during the first year, indicating a learning effect. Failures in the permanent dentition were due to marginal ridge fracture (35%), cavitation in the approximal enamel (31%), and recurrent caries (38%). Failures in primary teeth were predominantly due to marginal ridge fractures (84%). A comparison with the longevity of conventional Class II restorations is made and the possible advantages of the present method are presented.