Metallic posts fall short of satisfying contemporary guidelines for ideal post / core rehabilitation. Along with technological advancements in adhesive resin cements and composite restoratives, the evolution of fiber-reinforced posts allows the rehabilitation of endodontically treated teeth with greater esthetics anv virtually no predisposition to root fracture. At least one fiber post system now complies with all of the ideal post characteristics described in the endodontic text. This article describes the potential for displacement of metal posts by low-modulus fiber posts, the differences between them and the development and clinical placement of a radiopaque, translucent, double-tapered fiber post.

Recently there is a clearly observable movement toward use of fiber-reinforced resin-based composite posts used in conjunction with composite build-ups. The resin-cemented fiber posts, followed by composite build-ups were as strong as the metal posts used with composite build-ups. They do NOT impart any objectionable color to the tooth. In terms of most of the necessary post characteristics, the fiber posts are superior to metal prefabricated posts. They are easy to place, are relatively inexpensive, can be bonded to resin cement, and are easy to remove if the tooth needs to be retreated endodontically.

Abstract/conclusions:Some years ago, we created the following classifications for endodontic posts: (1) first generation posts (self-threaded posts, screw posts, serrated-carved posts); (2) second generation posts (passive posts); (3) third generation posts (nonmetallic passive posts). In this last group, we placed carbon-fiber posts, (Composipost) which have a modulus of elasticity very similar to the modulus of elasticity of dentine and can realize a tooth-post-core monobloc instead of an assemblage of heterogeneous materials. This is quite a new philosophy in rebuilding endodontically treated teeth and is based on the use of integratable materials that homogeneously distribute masticatory loads and reduce stress.

Objectives: Prefabricated fiber posts, used in the restoration of endodontically treated teeth, routinely require a reduction in length, to accommodate the individual patient. This study evaluated the effect of trimming fiber posts with either a diamond bur or a diamond disk.
Methods: Five different post systems: 1) CF Carbon fiber post (J. Morita USA Inc), 2) DT Light-Post (Bisco Inc.), 3)FRC Postec (Ivoclar Vivadent) Parapost FW (Coltene Whaledent), 5)Twin Lucent (Dentatus USA), were trimmed with either a diamond bur (8862) or a diamond disk (911HF, Brasseler USA). Two different core systems were used CompCore AF (Premier) and Light Core (Bisco Inc). The posts were cut, once through the core material and once at 3mm above the apical end. The cut surfaces were then evaluated by SEM. The surfaces showed various degrees of resin loss between the fibers. Two investigators estimated the total surface area with resin loss.
Results: The observed surface area (in %) with resin loss is listed below. No differences were observed between the two core materials, hence all core data have been combined.

	Disk cut		Bur cut
Post system	Core	Apex	Core	Apex
CF Carbon Fiber	0	13	0	20
DT Light post	0	7	0	14
FRC Postec	25	85	70	0
Parapost FW	2	8	20	10
Twin Lucent	0	30	6	60

Conclusions: From these data we conclude that: 1) the use of a diamond disk produces less resin loss from the fiber post, when compared to a diamond bur, and 2) that for those fiber posts, for which by design the coronal part of the post is to be trimmed, the post should be trimmed after the post and the core material have been placed. The materials for this study have been provided by the various manufacturers, and their support is hereby acknowledged.

Abstract/conclusions: Prosthetic treatment failures related to the biomechnical deficiencies of post and cores still represent a problem of clinical significance. To overcome the difficulties of clinical studies, numerous in vitro methods were developed to address specific properties of post-and-core restorations. Most of them, however, were based on an oversimplified mechanical testing of the restored tooth. Experience proved that the fatigue of the restored materials was a primordial factor in clinical failures. Therefore, special devices were built that simulate the physiological masticatory cycle. Tests performed with adhesive post-and-core systems seem to indicate that materials placed in the tooth should have physical properties as close as possible to those of natural tissues. New carbon-epoxy posts (Composipost) appear to offer a promising solution for restoring the endodontically treated tooth.

Abstracts/conclusions: Metallic prefabricated posts have dominated the market for a number of years. Yet, in the past several years, polymeric, ceramic carbon or fiber-reinforced, and other novel systems have emerged into the post material market. These newer systems have focused on physical properties, such as modulus of elasticity (rigidity), more closely matched to dentin, to reduce stress concentrations within the root canal and reduce the incidence of fractures. An additional feature with the newer posts has been the esthetics with composite core materials. Minimal clinical research or simulation studies are available; however, results have been favorable, with high retention rates and a lack of root fractures.With the abundance of literature demonstrating that metallic posts have a greater number of disadvantages over selective modern technologies, it is now time to examine the dental school academic cirriculums concerning post techniques. As more clinical data becomes available, the guidelines for post selection in restoring endodontically treated teeth should become more defined and a general consensus may be reached.

Abstract / conclusions: This report presents a case in which a “one-bottle” adhesive system (ONE-STEP) was used in combination with proprietary resin cement for bonding a fiber post. The fiber post was placed into the root canal of a fractured root under clinical conditions and then extracted 1 week later. Using Scanning Electron Microscopy, half of the root was evaluated for hybrid layer formation and the other half for assessing resin tags. The investigation demonstrated that the one-bottle system can infiltrate and create a mechanical interlocking with etched root dentine.

Abstract/conclusions: The Light-Post is a 15-year evolution of post research at RTD. Its genesis began with the carbon fiber Composipost/ C-POST, transformed into the AesthetiPlus, made of white quartz fiber, and finishing with the Light-Post, made ouit of translucent quartz fiber. This transition from Carbon to Quartz was completed without any compromise in strength, modulus of elasticity, resistance to fatigue or the ability for re-treatment. The Light-Post offers clinicians significant aesthetic and clinical advantages due to its translucency.

Abstract/conclusion: Use of a post system for the rehabilitation of endodontically treated teeth requires traditional planning for the function of the restoration as well as a structural and aesthetic strategy for novel technologies in ceramic and composite dentistry. Contemporary material options have greatly expanded the clinician’s ability to rehabilitate the corono-radicular complex. Transilluminating posts, bondable fabrics and high-technology ceramics create exciting possibilities in post and core design. The use of bondable materials allows the practitioner to unify the structure and morphology of root systems to provide creative solutions to challenges heretofore unmet.

Abstract/conclusions: This article provides a brief overview of important, recent changes in the philosophy, materials and technology that have impacted significantly on the art and science of endodontic post placement. The growing interest in esthetic dental restorations and adhesion dentistry has driven both manufacturers and dentists to create some innovative new post materials and techniques for restoring the endodontically treated tooth. Although metal posts were used extensively for many years, their popularity is currently in the decline. With more than 10 years of proven clinical success, there is now widespread interest in the use of non-metallic post materials and techniques. Over the last decade, in vitro and in vivo testing has demonstrated that some fiber-reinforced endodontic posts can dramatically reduce the incidence of root fracture, tissue discoloration and allergic reaction. If endodontic re-treatment is necessary, most fiber posts can be removed from a root canal with ease and predictability when necessary without compromising their only true function; core retention. Today's marketplace offers the dentist many choices in size, radiopacity and designs to fit the needs of the specific tooth and clinical application. The use of a highly translucent post not only can serve to enhance esthetics in the final restoration, but can also be useful as an instrument in the light-curing process.

Abstract/conclusions: Utilization of contemporary post and core systems has facilitated the aesthetic restoration of endodontically treated teeth. Light transmission and biocompatibility have been enhanced by the introduction of metal-free post systems. The periodontal and endodontic status, root length and histological structure of the devitalized teeth must be considered in order to achieve successful restoration after endodontic treatment. This article presents various restorative criteria for the esthetic placement and buildup of post and core materials, as well as the preservation of maximum coronal and root structure.

Abstract/ conclusions: The aim of this study was to compare the mechanical properties of a prefabricated root canal post made of carbon fiber reinforced composites (Composipost; RTD, St. Egreve France) with metal posts and to assess the cytotoxic effects elicited. Flexural modulus and ultimate flexural strength was determined by 3 point loading after Composipost posts had been stored either dry or in water. The bending test was carried out with and without preceding thermocycling of the Composipost posts. The cytotoxicity was evaluated by an agar overlay method after dry and wet storage. The values of flexural modulus and ultimate flexural strength were for dry stored Composipost 82+6 GPa and 1154+65 MPa respectively. The flexural values decreased significantly after water storage and after thermo-cycling. No cytotoxic effects were observed adjacent to any Composipost. Although fiber reinforced composites may have the potential to replace metals in many clinical situations, additional research is needed to ensure a satisfying life span.