Fiber-reinforced Composite Framework Research Articles

Fiber-reinforced composite partial fixed dental prostheses supported by short or extra-short implants: A 10 year retrospective study.

This study evaluated the 10-year survival and success of partial fixed dental prostheses (P-FDPs) fabricated with a milled fiber-reinforced composite (FRC) framework, supported by short or extra-short implants. Patients restored with FRC P-FDPs supported by short or extra-short implants were included in this retrospective study. Kaplan-Meier analysis was used to calculate the survival and success rates of the prostheses. Univariate and multivariate Cox regression models, clustered to adjust for multiple implants and prostheses being placed in the same patient, were used to correlate changes in peri-implant bone levels with patient, implant, and prosthesis-related covariates. This study followed 121 FRC P-FDPs supported by 261 implants, placed in 96 patients. At 118 months in function, the P-FDP survival rate was 95.9% (95% CI: 87.5%-98.7%), and the success rate was 89.8% (95%CI: 80.4%-94.8%). Differences in prosthesis span length, abutment/pontic ratio, and the presence of distal extensions (cantilevers) did not affect the prosthetic outcomes. Bone levels around implants were stable, with an average rate of change of -0.01 ± 0.05 mm/month. Cox regression revealed that grafted sites were correlated with peri-implant bone loss, while longer prosthetic spans were correlated with bone gain. P-FDPs comprised of milled fiber-reinforced composite frameworks, supported by short and extra-short implants, had high survival and success rates for up to 10 years.

Performance of crowns cemented on a fiber-reinforced composite framework 5-unit implant-supported prostheses: in silico and fatigue analyses

ObjectiveTo characterize the biomechanical performance of fiber-reinforced composite 5-unit implant-supported fixed dental prostheses (FDPs) receiving individually milled crowns by insilico and fatigue analyses. MethodsEighteen implant-supported five-unit fiber-reinforced composite frameworks with an individually prepared abutment design were fabricated, and ninety resin-matrix ceramic crowns were milled to fit each abutment. FDPs were subjected to step-stress accelerated-life testing with load delivered at the center of the pontic and at 2nd molar and 1st premolar until failure. The reliability of the prostheses combining all loaded data and of each loaded tooth was estimated for a mission of 50,000 cycles at 300, 600 and 900 N. Weibull parameters were calculated and plotted. Fractographic and finite element analysis were performed. ResultsFatigue analysis demonstrated high probability of survival at 300 N, with no significant differences when the set load was increased to 600 and 900 N. 1st and 2nd molar dataset showed high reliability at 300 N, which remained high for the higher load missions; whereas 1st premolar dataset showed a significant decrease when the reliability at 300 N was compared to higher load missions. The characteristic-strength of the combined dataset was 1252 N, with 1st molar dataset presenting higher values relative to 2nd molar and 1st premolar, both significantly different. Failure modes comprised chiefly cohesive fracture within the crown material originated from cracks at the occlusal area, matching the maximum principal strain location. SignificanceFive-unit implant-supported FDP with crowns individually cemented in a fiber-reinforced composite framework presented a high survival probability. Crown fracture comprised the main failure mode.

Static and Fatigue Loading of Veneered Implant-Supported Fixed Dental Prostheses.

This study aimed to compare the load to failure and the probability of survival of porcelain fused to zirconia (PFZ) three-unit, implant-supported, fixed dental prostheses (FDPs) to those of indirect composites veneered to either zirconia (CVZ) or milled fiber-reinforced composite (FRC) frameworks under static and fatigue loading. One-hundred and twenty posterior three-unit FDP (second premolar pontic) frameworks were fabricated via milling from a single Standard Tessellation Language (STL) file. The FDPs were divided into three groups. Each group (n = 40) was subjected to static (n = 20) and fatigue (n = 20) loading tests, as follows: (1) PFZ: zirconia framework layered with porcelain veneer; (2) CVZ: zirconia framework veneered with indirect composite resin; and (3) FRC: FRC framework veneered with indirect composite resin. After porcelain veneering onto sintered zirconia frameworks, or resin composite veneering onto zirconia or FRC frameworks, FDPs were cemented on their abutments using self-adhesive resin cement. After thermal cycling, half of the FDPs were subjected to an accelerated fatigue test. The other half of the FDPs were subjected to single load-to-failure (SLF) testing at a crosshead speed (1 mm/min). Lifetime analysis was conducted to determine the probability of survival, and fractographic analysis was performed. Significant differences were observed among the studied groups for SLF with the highest characteristic strength values observed for PFZ (2154 N), followed by 1905.47 N for CVZ and 1679.56 N for FRC. The probability of survival for 100,000 cycles at 500 N was the highest for FRC (98%) and CVZ (100%) and was significantly lower for PFZ (88%). Different fracture patterns were observed in the fractography. In fatigue testing, which simulates masticatory function better than static tests, a higher probability of survival was observed for FRC and CVZ than for PFZ. Framework fractures were not observed only for the FRC group, indicating that chairside repair with the addition of indirect composite could be performed for continued function.

Laser Doppler imaging of skin microcirculation under fiber-reinforced composite framework of facial prosthesis

Objective. Glass-fiber reinforced composite has been suggested to be used as framework material in silicone elastomer facial prostheses. The glass-fiber reinforced framework makes it possible to make the margin of the prosthesis very tight, so that it will lean tightly against the skin even during facial expressions and jaw movements. The purpose of this study was to study how the compression of the glass-fiber reinforced framework would affect the microcirculation of the facial skin. Materials and methods. A face mask, with a compression pad corresponding to the outer margin of a glass fiber-reinforced composite framework beam of a facial prosthesis, was used to apply pressure on the facial skin of healthy volunteers. The skin blood flow during touch, light and moderate compression of the skin was measured by laser Doppler imaging technique. Results. None of the compressions had any marked effects on local skin blood flow. No significant differences between the blood flow of the compressed skin, compared to the baseline values, were found. Conclusions. The pressure applied to the skin by the tight margins of a facial prosthesis, fabricated with a framework of glass-fiber reinforced composite, does not remarkably alter the skin blood flow.

Biomechanical comparison of implant retained fixed partial dentures with fiber reinforced composite versus conventional metal frameworks: A 3D FEA study

Fiber reinforced composite (FRC) materials have been successfully used in a variety of commercial applications. These materials have also been widely used in dentistry. The use of fiber composite technology in implant prostheses has been previously presented, since they may solve many problems associated with metal alloy frameworks such as corrosion, complexity of fabrication and high cost. The hypothesis of this study was that an FRC framework with lower flexural modulus provides more even stress distribution throughout the implant retained fixed partial dentures (FPDs) than a metal framework does. A 3-dimensional finite element analysis was conducted to evaluate the stress distribution in bone, implant–abutment complex and prosthetic structures. Hence, two distinctly different models of implant retained 3-unit fixed partial dentures, composed of Cr–Co and porcelain (M-FPD model) or FRC and particulate composite (FRC-FPD model) were utilized. In separate load cases, 300 N vertical, 150 N oblique and 60 N horizontal forces were simulated. When the FRC-FPD and M-FPD models were compared, it was found that all investigated stress values in the M-FPD model were higher than the values in the FRC-FPD model except for the stress values in the implant–abutment complex. It can be concluded that the implant supported FRC-FPD could eliminate the excessive stresses in the bone–implant interface and maintain normal physiological loading of the surrounding bone, therefore minimizing the risk of peri-implant bone loss due to stress-shielding.

Chairside Fabricated Fiber-Reinforced Composite Fixed Partial Denture

The advances in the materials and techniques for adhesive dentistry have allowed the development of non-invasive or minimally invasive approaches for replacing a missing tooth in those clinical situations when conservation of adjacent teeth is needed. Good mechanical and cosmetic/aesthetic properties of fiber-reinforced composite (FRC), with good bonding properties with composite resin cement and veneering composite are needed in FRC devices. Some recent studies have shown that adhesives of composite resins and luting cements allow diffusion of the adhesives to the FRC framework of the bridges. By this so-called interdiffusion bonding is formed [1]. FRC bridges can be made in dental laboratories or chairside. This article describes a clinical case of chairside (directly) made FRC Bridge, which was used according to the principles of minimal invasive approach. Treatment was performed by Professor Vallittu from the University of Turku, Finland.

The Bond Strength of Particulate‐Filler Composite to Differently Oriented Fiber‐Reinforced Composite Substrate

The primary failure mode of fiber-reinforced composite (FRC) materials used intraorally is delamination or debonding of particulate filler composite (PFC), the esthetic veneer, from the underlying FRC framework. The objective of the current study was to evaluate the effect of unidirectional fiber orientation and load direction on the shear bond strength of PFC to FRC. Unidirectional E-glass FRC was used as an adhesion substrate for the PFC. E-glass FRCs were oriented in three ways--Group A: in the plane perpendicular to the bonding surface; Group B: along the bonding surface longitudinal to the load; and Group C: along the bonding surface, transverse to the load. The FRC substrates were ground flat with 1200 grit. The PFC adherend was bonded to FRC using an intermediate resin. Twelve specimens for each group were water stored (37 degrees C) for 3 days before a shear bond strength test was conducted. A one-way analysis of variance showed that the direction of the applied load to the fiber direction had a significant effect on the bond strength values (p < 0.001). A Weibull analysis produced values (characteristic strength and Weibull modulus) of Group A (46.5 MPa, 12.1), Group B (40.6 MPa, 4.6), and Group C (27.6 MPa, 3.5). The highest shear bond strength values and Weibull modulus were obtained when the fibers were oriented perpendicular to the bonding surface, exposing the fiber ends to the PFC. Interface strategies between hybrid composite layers may be developed to exploit anisotropic behavior in the adherence between FRC and PFC.

Morphological and functional rehabilitation of severely infra-occluded primary molars in the presence of aplasia of the permanent premolar: A clinical report

This clinical report describes the fixed prosthodontic rehabilitation of an infra-occluded primary molar. Diagnostic considerations included the patient's age, occlusal status, condition of the infra-occluded tooth including the degree of infra-occlusion and root resorption, as well as adjacent alveolar bone levels. Due to the patient's young age, an invasive prosthetic approach was delayed in favor of an onlay restoration, which represented a more rapid and conservative therapeutic choice. The treatment involved the design and fabrication of a composite onlay on the deciduous molar using a ceramic optimized polymer on a fiber-reinforced composite framework. Three years later, intraoral radiography showed satisfactory marginal adaptation. No change was observed in periodontal tissues.

Fiber-reinforced composite framework for implant-supported overdentures

This article presents a new method for fabricating a framework for an implant-supported overdenture using unidirectional fiber-reinforced composite. This procedure eliminates the need for a traditional metal alloy framework. The fiber-reinforced composite framework has the advantages of lower cost, less time and materials needed during fabrication, minimal potential for toxicity to the technician and patient, and a more esthetic metal-free final result. (J Prosthet Dent 2000;84:200-4.)