The Resin-Bonded Fixed Partial Denture as the First Treatment Consideration to Replace a Missing Tooth.

The resin-bonded fixed partial denture (RB-FPD) is the first restorative treatment option to be considered in cases where one or more teeth are missing. The indications for implants, conventional FPDs, and adhesive FPDs, considering the general and dental conditions of the patient, are discussed in this article. When the RB-FPD is the chosen option, a direct or indirect technique, a cantilever-type or fixed-fixed design, and materials to be used need to be selected. The choice will depend on a variety of factors, such as interproximal space at the connector area, anterior or posterior location, the skills of the dentist, esthetics, and the patient's wishes. The RB-FPD can be made using various techniques and materials.

Static and dynamic failure load of fiber-reinforced composite and particulate filler composite cantilever resin-bonded fixed dental prostheses.

PURPOSE: The aim of this study was to evaluate in vitro the influence of fiber reinforcement and luting cement on the static failure load (SFL) and dynamic failure load (DFL) of simulated two-unit cantilever resin-bonded fixed dental prostheses (RBFDPs). MATERIALS AND METHODS: Forty-six particulate filler composite (PFC) beams and 76 fiber-reinforced composite (FRC) beams were prefabricated and subsequently luted (RelyX ARC or Panavia F2.0) onto flat ground bovine enamel. The SFL of the different specimen types was determined with a peel test and the DFL was determined with a rotating cantilever beam fatigue testing device. RESULTS: The PFC specimens showed a significantly lower SFL than the FRC specimens. The luting cement showed a significant effect on the SFL of the PFC specimens, but not with FRC. The DFL of PFC specimens was significantly lower than for FRC specimens. The luting cement showed a significant effect on the DFL of the PFC specimens, but not so with FRC. With both the SFL and the DFL tests all PFC beams fractured, leaving the bonded part on the tooth surface, but FRC beams partially debonded from the tooth surface, leaving fibers connected to the enamel surface to a varying extent. Coincidentally, the uncured fibers turned out to be prone to aging, an effect which has been investigated. CONCLUSION: Within the limitations of this study, it can be concluded that PFC without fiber reinforcement is not suitable for the fabrication of two-unit cantilever RBFDPs, despite the significant effect of the luting cement, but FRC is suitable.

Fracture strength and fatigue resistance of dental resin-based composites.

OBJECTIVES: The aim of this study was to evaluate in vitro the influence of fiber-reinforcement on the fracture strength and fatigue resistance of resin-based composites. METHODS: One hundred rectangular bar-shaped specimens (2 mm x 2 mm x 25 mm) made of resin-based composite were prepared in a stainless steel split-mould: (i) thirty specimens of particulate filler composite (PFC) (Filtek Z100, 3M ESPE, St Paul, MN, USA), (ii) thirty specimens of fiber-reinforced composite (FRC) (Everstick C&B, Sticktech Ltd., Turku, Finland) and (iii) forty specimens of PFC and FRC combined in two longitudinal layers of equal thickness. Each specimen was trimmed into a cylindrical hourglass shape. The fracture strength (cantilever beam test, n=10) and the fatigue resistance (rotating cantilever beam test; staircase method: 10(4) cycles, 1.2 Hz, n=20) were determined. Fracture strength, fatigue resistance and work-of-fracture were calculated. The fracture surfaces of failed specimens were analyzed with SEM. Data was analyzed by logistic regression, one-way ANOVA followed by Tukey's post hoc test and, a Student's t-test. RESULTS: ANOVA revealed that fiber-reinforcement had significant effect (P<0.001) on fracture strength, fatigue resistance, and work-of-fracture. Student's t-test showed significant differences (P<0.001) in fatigue resistance compared to fracture strength. CONCLUSIONS: Within the limitations of this study, the following conclusions can be drawn (i) the fatigue resistance of resin-based composites is lower than their fracture strength and (ii) FRC are more fatigue resistant than PFC or combinations of FRC and PFC.

In vitro exploration and finite element analysis of failure mechanisms of resin-bonded fixed partial dentures.

PURPOSE: The purpose of this study was to explore the debonding mechanisms of two-unit cantilevered and straight and bent three-unit fixed-fixed resin-bonded fixed partial dentures (RBFPDs) and to measure the failure loads needed for debonding. MATERIALS AND METHODS: Failure load tests were performed using Bondiloy beams simulating both cantilevered and fixed-fixed RBFPDs, luted onto flat-ground buccal surfaces of bovine teeth with RelyX ARC, Panavia F2.0, and UniFix resin cements. The failure loads were recorded, and the debonded surfaces of both the enamel and the restorations were examined for details of interest. Finite element analysis (FEA) was used to calculate the stress concentrations within the cement layers at failure. RESULTS: Simulated two-unit cantilevered and straight three-unit fixed-fixed RBFPDs showed a significantly higher failure load than the simulated three-unit fixed-fixed RBFPDs with a curved appearance. The FEA models revealed the magnitude and stress locations within the cement layer, resulting in an explanation of the different failure modes. CONCLUSIONS: The low failure loads for the three-unit bent fixed-fixed RPFPDs, compared with their straight counterparts and the two-unit cantilevered RBFPDs, indicate that clinically a reserved attitude needs to be maintained with regard to three-unit fixed-fixed RBFPDs spanning a clearly curved part of the dental arch. The FEA results make it clear which part of the tooth restoration interface is subject to the highest stress levels, making it possible to design abutment preparations that avoid high interfacial stresses to help prevent debonding.

Influence of cementation variables on fatigue of simulated two-unit cantilever resin-bonded fixed partial dentures.

PURPOSE: To determine the influence of various combinations of surface pretreatment and luting cement on flexural fatigue limits of two-unit CoCr cantilever resin-bonded fixed partial dentures. METHODS: Cyclic fatigue tests were performed at 1 Hz on an ACTA fatigue tester. The staircase test method was used on CoCr beams, simulating cantilever resin-bonded fixed partial dentures, using flat ground bovine teeth as substrate. Two series of tests have been executed: (1) 10(4) cycles, and (2) 10(5) cycles. Prior to cementation, the CoCr beams were subjected to either sandblasting or Rocatec or Silicoater treatments. Three commercially available resin luting cements were used. Fatigue tests were performed 72 hours after cementation and storage in 37 degrees C tap water. Each possible combination of cement and pretreatment (n = 20) was tested. RESULTS: One cement, UniFix, showed hardly any debondings with any of the three surface pretreatments. The other two cements, RelyX ARC and Panavia, both showed significantly better performance with Rocatec than when pretreated with sandblasting or Silicoater.

In vitro evaluation of failure loads of nonmetal cantilevered resin-bonded fixed dental prostheses.

PURPOSE: To evaluate in vitro the influence of fiber reinforcement on the failure loads of resin composite beams, simulating cantilevered two-unit resin-bonded fixed dental prostheses, and compare the results with similarly obtained failure loads of ZrO2 and CoCr beams of a comparable design. MATERIALS AND METHODS: Peel tests were performed using resin composite, fiber-reinforced resin composite, and zirconia beams, simulating two-unit cantilevered resin-bonded fixed dental prostheses, luted with Panavia F2.0 onto flat-ground buccal surfaces of bovine mandibular incisors. The recorded failure loads were compared with those of CoCr beams of a similar size and design from earlier research. Finite element analysis revealed the stress concentrations within the cement layers at failure. RESULTS: The failure loads (N) of the peel tests, depending on the beam type and including the type of failure, were statistically analyzed. The highest failure values were obtained with the fiber-reinforced resin composite beams, which were luted with the exposed fibers directly on the bovine enamel. Finite element analysis showed that peak stress locations depend on the beam type and facilitate the explanation of the different failure modes. CONCLUSION: Fiber-reinforcement of simulated two-unit cantilevered resin composite resin-bonded fixed dental prostheses does not necessarily lead to higher failure loads. This study identified significant differences in peel failure loads between identical specimens, depending on whether or not the fiber reinforcement was exposed on the luting surface. Further research needs to be carried out regarding the combination of resin composite and fiber reinforcement.

The influence of surface treatment and luting cement on in vitro behavior of two-unit cantilever resin-bonded bridges.

OBJECTIVES: The purpose of this study was to find the optimal combination of surface pretreatment and luting cement for two-unit CoCr cantilever resin-bonded bridges. METHODS: Tensile peel, load and torque strength tests were performed using flat ground bovine teeth as substrate, four different commercially available luting cements, and CoCr beams as simulated cantilever resin-bonded bridges. The CoCr beams were pretreated with sandblasting or Rocatec. Tensile peel, load and torque strengths were determined 72h after cementation. The effects of sandblasting and Rocatec pretreatments on the morphology of the CoCr surface was investigated with SEM and EDAX analysis. RESULTS: The average strengths of the three tests showed that Rely X ARC, Resiment and Panavia were the same and significantly lower than UniFix. Rocatec showed a significantly higher average bond strength than sandblasting considering all tests. The peel test, which showed the lowest failure values, is clinically the most relevant test. This test showed that only UniFix as luting cement with sandblasting as pretreatment generates a significantly higher bond strength compared with the other cements and pretreatments. SIGNIFICANCE: Based on the results of this study the use of Unifix with sandblasting as metal surface pretreatment, is preferred for cementation of two-unit CoCr cantilever resin-bonded bridges.

A literature review of two-unit cantilevered FPDs.

PURPOSE: This review article evaluated the clinical performance of two-unit cantilevered, single-abutment, single-pontic, resin-bonded fixed partial dentures (FPDs) by comparing them to noncantilevered resin-bonded FPDs with two abutments and a single pontic. MATERIALS AND METHODS: One publication on design principles and 11 clinical research studies were selected by searching two databases. RESULTS: Six of the studies dealt exclusively with two-unit cantilevered resin-bonded FPDs, and five studies compared fixed-fixed design resin-bonded partial dentures with cantilevered resin-bonded FPDs. Two-unit cantilevered resin-bonded FPDs for single-tooth replacement appear to be reliable and predictable restorations, provided their preparations meet the right standards. CONCLUSION: According to the studies reviewed, two-unit cantilevered FPDs show better longevity than resin-bonded fixed-fixed partial dentures in similar situations.