Gingival Microleakage of Class II Resin Composite Restorations with Fiber Inserts

Abstract

Fiber inserts incorporated at the gingival floor of Class II composite restorations resulted in a significant reduction of microleakage scores as compared to restorations made without inserts. This may lead to a reduced incidence of recurrent caries. SUMMARYPurpose: This investigation evaluated the effect of glass and polyethylene fiber inserts on the microleakage of Class II composite restorations with gingival margins on root surfaces. Methods: Fifty-four intact molars were sterilized with Gamma irradiation and mounted in acrylic bases. Class II slot cavities were made on both proximal sides of each tooth (3 mm wide, 1.5 mm deep) with the gingival margin on the root surface. The teeth were divided into nine groups, according to the technique of restoration and type of bonding agent. Filtek P-60 (3M/ESPE) was used to restore all cavities. Two types of fiber inserts were used: glass fiber (Ever Stick, StickTech) and polyethylene (Ribbond-THM), with three bonding agents being employed: Scotch Bond Multipurpose (3M/ESPE), Clearfil SE Bond (Kuraray) and Xeno IV (Dentsply). In the experimental groups, 3 mm long fiber inserts were inserted into restorations at the gingival seat. The control groups had no fiber inserts. The restorations were made incrementally and cured with LED light (UltraLume5, Ultradent). The restored teeth were stored in water for two weeks, then thermocycled for 3,000 cycles (5°C and 55°C). The tooth surfaces were sealed with nail polish, except at the restoration margins. The teeth were immersed in 2% procion red dye solution, sectioned and dye penetration was assessed to determine the extent of microleakage

Effects of remineralization procedures on shear bond strengths of brackets bonded to demineralized enamel surfaces with self-etch systems

“…26 Therefore, we performed the thermocycling procedure for 5000 cycles to represent the clinical situation as closely as possible. Although the laboratory conditions do not fully reflect the oral environment, it provides an idea of the clinical performance of the various groups tested.…”

Gingival Microleakage of Class V Composite Restorations with Fiber Inserts

“…In contrast, El-Mowafy and others 5 and Basavanna and others 17 found significant reductions in microleakage when glass or polyethylene fibers were placed on the gingival margin of class II composite restorations. There are different reasons to explain the variability in the outcomes of those studies compared to the present study.…”

“…18 In contrast, in the present study (class V) the polymerization light was applied directly to the composite increment without a matrix. Another factor that may have contributed to the difference in results between class II and V studies is the variability in the cavity size.In a previous study 5 the class II slot cavities were performed in molar teeth, and measured 3 mm wide × 1.5 mm in axial depth, with the gingival floor located at least 1 mm below the CEJ on the root surface. Although a class II cavity presents less C-factor than class V, characteristics such as cavity depth, number of resin layers, lower light intensity that reaches class II gingival floor due to irradiation been performed from coronal direction may account to a higher leakage.…”

“…The use of fiber inserts, both glass or polyethylene has been shown to significantly reduce gingival microleakage in class II composite restorations with gingival margins in dentin, irrespective of the bonding agent used. 5 In addition, substantial improvements in mechanical properties were achieved when resin composites were reinforced with fiber inserts that resulted in restorations with higher flexural strength, toughness and elastic modulus, rendering them more resistant to deformation and fracture.…”

“…4 Methods to reduce polymerization shrinkage have focused on either chemical modifications to the composite material formulations, or modified clinical procedures such as different composite insertion techniques, the application of flowable resin liner, new adhesive systems, modified light curing procedures and the incorporation of fiber inserts. 1,5 The predominant organic matrix used in commercial dental composites consists of bisphenolglycidyl dimethacrylate (Bis-GMA) diluted with triethylene glycol dimethacrylate (TEGDMA). 6 Recently, silorane low shrinking commercial dental composites have been introduced to the market.…”