Applications, benefits, and limitations of fiber-reinforced composites in fixed prosthodontics

This study offers a comprehensive evaluation of the efficacy, benefits, and limitations of fiber-reinforced composites (FRCs) in fixed prosthodontics. Emerging as a substitute for conventional dental materials such as metals and ceramics, FRCs are now used in a variety of applications, from dental crowns and bridges to veneers. The study is based on an exhaustive literature review and explores various properties of FRCs, such as mechanical, optical, viscoelastic, adhesive, and thermal attributes. The strength and rigidity of constructions made from FRC are dependent on the polymer matrix of the FRC and the type of fiber reinforcement. In dental appliances of relatively small sizes, the quality of the load bearing FRC sub-structure is very important. A special emphasis is placed on the clinical applications and future potential of these materials. The advantages of using FRCs include their biocompatibility, light weight, durability, and aesthetic superiority. However, there are limitations, such as higher costs and concerns about long-term clinical performance, specifically related to interface degradation. The study concludes that FRCs hold significant promise in the domain of fixed prosthodontics, although further research is needed for optimizing their long-term effectiveness.

Comportamiento clínico de prótesis fijas de resina compuesta reforzadas con fibra: evaluación a 5 años: resultados finales / Clinical behavior of fixed prostheses of fiber-reinforced composite: five-years follow-up: final results

El objetivo de este estudio fue evaluar parámetros clínicos en Prótesis Fijas de Resina Compuesta Reforzada con Fibra (PFs-RCRF), en pacientes de la Clínica de Prostodoncia Fija de la Universidad Católica del Uruguay. Se realizó un estudio observacional, longitudinal, analítico. Se seleccionaron 25 pacientes entre 18 y 65 años con ausencia de una pieza posterior y con antagonistas naturales, restaurados o no. Las PFsRCRF fueron realizadas por docentes, y estudiantes de 5° año bajo supervisión docente. Un observador calibrado (Kappa 0.88) controló cada 6 meses durante 5 años y evaluó tomando como referencia criterios de Ryge G (1980) simplificados. Se consideró Alfa (A: sin alteración), Beta (B: alteraciones que no requieren tratamiento) y Charlie (Ch: necesidad de reciclado o recambio). Se controló Tinción Marginal (TM), Integridad Marginal (IM), Superficie (S) y Color (C). Se hicieron 10 controles en 20 PFs-RCRF y los resultados promedio de los retenedores fueron: TM: A: 47,6%, B: 48,3%, Ch: 4,1%; IM: A: 33,6%, B: 61,8%, Ch: 4,6%; S: A: 62,4%, B: 32,5%, Ch: 5,1% C: A: 73,7%, B: 23,6%, Ch: 2,7%. Los resultados promedio de los pónticos fueron: S: A: 59,7%, B: 34,9%, Ch: 5,4%; C: A: 90,1%, B: 6,9%, Ch: 3%. Se concluye que las PFs-RCRF han demostrado en 5 años, ser una alternativa funcional, estética, rápida, reciclable, de bajo costo y relativamente buena confiabilidad. Son fáciles de remover y reemplazar si fuera menester. Son importantes los controles periódicos para el éxito de dichas estructuras.

The aim of the study was to assess clinical parameters in Fixed Prosthesis of Fiber-Reinforced Composite (FPs-FRC) in patients of Fixed Prosthodontic Clinic of the Universidad Católica del Uruguay. An observational, longitudinal and analytic study was carried out. Twenty-five patients between 18 and 65 years old with a missing posterior with natural antagonists restored or not, were selected. The FPs-FRC were produced by teachers, and 5th year students – teaching supervision. One calibrated observer (Kappa 0,88) controlled every 6 months during 5 years and assessed taking as reference the simplified criteria of Ryge G (1980). The following was considered: Alpha (A: no alteration whatsoever), Bravo (B: minor alterations not requiring treatment) and Charlie (Ch: recycling or replacement needed). Marginal Staining (MS), Marginal Integrity (MI), Surface (S) and Color (C) were controlled. Ten controls were made in 20 FPs-FRC and average results of retainers were as follows: MS: 47,6%, B: 48,3%, Ch: 4,1%; MI: A: 33,6%, B: 61,8%, Ch: 4,6%; S: A: 62,4%, B: 32,5%, Ch: 5,1%; C: A: 73,7%, B: 23,6%, Ch: 2,7%. Average results of pontics were the following: S: A: 59,7%, B: 34,9%, Ch: 5,4%; C: A: 90,1%, B: 6,9%, Ch: 3%. It is concluded that, FPs-FRC proved to be in 5 years, functional, aesthetic, quick, recyclable, low-cost and with relatively good reliability. They are easy to remove and replace if necessary. Periodic inspections are important for the success of these structures

Effect of fiber diameter on flexural properties of fiber-reinforced composites.

Background: Flexural strength (FS) is one of the most important properties of restorative dental materials which could be improved in fiber-reinforced composites (FRCs) by several methods including the incorporation of stronger reinforcing fibers. Aim: This study evaluates the influence of the glass fiber diameter on the FS and elastic modulus of FRCs at the same weight percentage. Materials and Methods: A mixture of 2,2-bis-[4-(methacryloxypropoxy)-phenyl]-propaneand triethyleneglycol dimethacrylate (60/40 by weight) was prepared as the matrix phase in which 0.5 wt. % camphorquinone and 0.5 wt. % N-N'-dimethylaminoethyl methacrylate were dissolved as photoinitiator system. Glass fibers with three different diameters (14, 19, and 26 μm) were impregnated with the matrix resin using a soft brush. The FRCs were inserted into a 2 × 2 × 25 mm 3 mold and cured using a light curing unit with an intensity of ca. 600 mW/cm 2 . The FS of the FRCs was measured in a three-point bending method. The elastic modulus was determined from the slope of the initial linear part of stress-strain curve. The fracture surface of the composites was observed using scanning electron microscopy to study the fiber-matrix interface. Statistical Analysis: The results were analyzed and compared using one-way ANOVA and Tukey's post-hoc test. Results: Although the FS increased as the diameter of fibers increased up to 19 μm (P < 0.05), no significant difference was observed between the composites containing fibers with diameters of 19 and 26 μm. Conclusion: The diameter of the fibers influences the mechanical properties of the FRCs.

Evaluation of biocompatibility of Targis Dentin and Artglass by using subcutaneous implantation test.

Introduction: Biocompatibility of a crown-bridge material is as important as its physical and mechanical properties. It is also one of the most important factors for the long-lasting clinical success of that restoration. It directly contacts the vital prepared tooth and that is the reason it has to be nontoxic to the local tissues, such as the pulp, gingiva, or the rest of the body. Materials with different physical properties are used in the conventional fixed prosthodontic restorations. Recently, metal-free systems that are reinforced with fibers have been improved for crown and bridge restorations. These new composite systems have the advantages of both ceramic and polymer chemistry. Materials and Methods: In this research, biocompatibility of two ceramic-polymer-based prosthetic materials (Targis Dentin® and Artglass Dentin® ) was studied using a subcutaneous implantation test on rats. Initially (15 th day) mild inflammatory reactions were observed in tissues, which directly contacted the Artglass, Targis, and control tubes. These probably originated from the surgical traumas. After the 90th day of implantation, these reactions resolved and healthy, well-organized fibrous connective capsules were seen around the implants. Results: Initially (15 th day) mild inflammatory reactions were observed in tissues, which directly contacted the Artglass, Targis, and control tubes. These probably originated from the surgical traumas. After the 90 th day of implantation, these reactions resolved and healthy, well-organized fibrous connective capsules were seen around the implants. Conclusion: At the end of the study, according to the FDI and ISO-7405 standards, Targis and Artglass indicated biocompatibility with the subcutaneous connective tissue of the rat.