Method of installing a dental fiber post and a dental fiber post system

Abstract

A method of installing a fiber post for a post and core dental restoration uses a fiber post system which has a plurality of fiber posts having at least two distinct diameters for the fiber posts and at least two preformed fiber post lengths for the fiber posts. Each fiber post containing a visible depth marker indicative of where the post should be placed above and below root orifice, whereby the fiber post selected is configured to be based upon the root length of the specific tooth obturated, yielding proper post space preparation apically for cementation and coronally for foundational core build up. The resulting implanted post eliminates or minimizes post manipulation during tooth preparation to create a mono-block of core material around the post during cementation and build up resulting in no disruption of either bond during preparation.

Description

METHOD OF INSTALLING A DENTAL FIBER POST AND A DENTAL FIBER POST SYSTEM RELATED APPLICATIONS

[0001] This application claims priority to United States provisional patent application Ser. No. 63 / 669,781 filed July 11, 2024, titled "Dental Fiber Post System Method of Installing” which application is incorporated herein by reference in its entirety. BACKGROUND INFORMATION

[0002] 1. Field of the invention

[0003] The present invention relates to a method of installing a dental fiber post and a dental fiber post system used in the same.

[0004] 2. Background Information

[0005] Post and core is a dental restoration treatment that is sometimes performed after a root canal procedure. When a significant portion of a tooth’s structure is removed, a post and core can help keep a dental crown in place. Dental crowns are dental restorations which are placed on top of teeth, to protect them from further damage or infection. During a root canal procedure, a portion of a patient’s tooth and the pulp-filled cavity in the root of the tooth is removed. In some instances, there may not be enough tooth left intact to return it to typical function. When this occurs, a post and core can be performed to better maintain a dental crown in place, and to reconstruct, or build the missing portions of the patient’s tooth.

[0006] Figures 1 and 2 schematically illustrate prior art post 30 and core 20 reconstructions for a tooth 74. During a post and core procedure, the root canal must be devoid of its original pulp-filled cavity or chamber (the root is still present). The post 30 goes inside the canal of the tooth 74 with the core 20 placed upon or formed upon the post 30, whereby the post 30 helps to mechanically retain the core 10 and the dental crown 10. The crown 10, core 20 and post 30 combine to form the dental restoration 40.

[0007] The patent literature yields some background for post and core dental restorations. For example, Russian patent publication.2339338 discloses a dental post is made as a fiberglass rod having narrow cylindrical part and a cone part, located on the one end of the narrow cylindrical part. Chinese patent publication CN2011102248493A discloses a CAD implemented method yielding an integrated non-metal post and core for dental restorations. Chinese patent publication CN103083094A discloses aAtlas 1 | P a g e Patent Applicationmanufacturing method of an all-ceramic post for dental restorations. Chinese patent publication CN1112618060A discloses a zirconia ceramic post and a manufacturing method thereof.

[0008] The development of endodontically treated teeth system restorations has increased the use of non-metallic posts. The development of dental materials has fundamentally altered the concept of post-and-core systems, allowing for a shift from mechanically retained restorations to adhesively retained ones. As non-metallic materials become more prevalent in indirect restorations, the properties and performance of the root canal posts and associated adhesives are of paramount importance. The adhesive interface between the post and dentin must be sufficiently strong to transmit the load from the occlusal surface to the periodontal ligaments and root. Zirconia posts, epoxy or methacrylate resin posts reinforced with quartz or glass fibers, polyethylene fiber- reinforced epoxy resin posts, and epoxy resin posts reinforced with carbon fibers are the most commonly used posts.

[0009] The susceptibility of endodontically treated teeth to fracture has long been a concern in dentistry, and continues with the use of fiber posts. Initially, it was believed that changes in the tooth dentine, such as reduced moisture content and decreased collagen cross-linking, were the leading causes of fractures See, for further details, Glazer, B. Restoration of endodontically treated teeth with carbon fiber posts-aprospective study. J. Can. Dent. Assoc. 2000, 66, 613–618. However, fractures ofendodontically treated teeth are generally now considered to be primarily caused by changes in tooth structural integrity. See also Soares, C.J.; Santana, F.R.; Pereira, J.C.; Araujo, T.S.; Menezes, M.S. Influence of airborne-particle abrasion on mechanical properties and bond strength of carbon / epoxy and glass / bis-GMAfiber-reinforced resin posts. J. Prosthet. Dent., 99, 444-454.

[0010] From a historical standpoint, fiber posts for dental restorations were introduced to clinical practice for the first time in France in 1989. Duret published the first research article on dental fiber posts in 1990 (Duret, B. New concept of coronoradicularreconstruction: The Composipost. Chir. Dent. Fr. 1990, 60, 131–141). Due to theirsuitable mechanical properties, such as tensile strength and stiffness, electrical conductivity, and low toxicity, carbon / graphite fibers were chosen for this application. This material revolutionized dentistry since it was an efficient alternative to metal posts. The modulus of elasticity of these fiber-reinforced materials was closer to that of dentin than the previously used metal posts, and the results of clinical studies were promising (seeAtlas 2 | P a g e Patent ApplicationNovais, V.R.; Quagliatto, P.S.; Della Bona, A.; Correr-Sobrinho, L.; Soares, C.J. Flexural modulus,flexural strength, and stiffness offiber-reinforced posts. Indian J. Dent. Res.2009, 20, 277.) Since their introduction, fiber posts have gained popularity among dentalclinicians due to their reliable clinical performance and variety of advantages, such as their mechanical, esthetic, and elastic properties. However, the initial fiber posts did have a disadvantage in terms of esthetics, as they were still visible beneath restorations made entirely of ceramic or composite. With the incorporation of quartz and glass fibers into the resin, more radiopaque fiber posts have been developed over time. This rendered the fiber posts translucent or white and therefore more aesthetically pleasing. In addition, they have been widely adopted due to their additional benefits, which include high tensile strength, resistance to biochemical degradation and solubility, low electrical conductivity, and low electrical conductivity.

[0011] Although fiber posts have demonstrated good physical and mechanical properties in vitro, numerous failures have been reported in clinical practice i) Bacchi, A. et al. Fracture strength and stress distribution in premolars restored with cast post-and- cores or glass-fiber posts considering the influence of ferule. BioMed Res. Int.2019; ii) Martins, M.D. et al Is afiber post better than a metal post for the restoration of endodontically treated teeth? A systematic review and meta-analysis. J. Dent., 112; iii) Fredriksson, M.; Astbäck, J. et al A retrospective study of 236 patients with teeth restoredby carbonfiber-reinforced epoxy resin posts. J. Prosthet. Dent. 1998, 80, 151–157; iv)Ferrari, M.; Vichi, A. et al Retrospective study of the clinical performance offiber posts. Am. J. Dent., 13, 9B-13B; v) Mannocci, F. et al Three-year clinical comparison of survival of endodontically treated teeth restored with either full cast coverage or with directcomposite restoration. J. Prosthet. Dent. 2002, 88, 297–301; vi) King, P.et al Clinicalevaluation of a carbonfibre reinforced carbon endodontic post. J. Oral Rehabil.2003, 30,785–789; vii) Bitter, K.; Noetzel, et al Randomized clinical trial comparing the effects of post placement on failure rate of postendodontic restorations: Preliminary results of amean period of 32 months. J. Endod. 2009, 35, 1477–1482; viii) Ferrari, M.et al Long-term retrospective study of the clinical performance offiber posts. Am. J. Dent.2007, 20,287.; ix) Sarkis-Onofre, R.et al Cast metal vs. glassfibre posts: A randomized controlled trial with up to 3 years of follow up. J. Dent.2014,42, 582–587; x) Cloet, E. et al Controlled Clinical Trial on the Outcome of Glass Fiber Composite Cores Versus Wrought Posts and Cast Cores for the Restoration of Endodontically Treated Teeth: A 5-Year Follow-up Study. Int. J. Prosthodont.2017, 30.Atlas 3 | P a g e Patent Application

[0012] The reported failure rate of endodontically treated teeth replacement with fiber- reinforced posts ranged from 2% to 40%. This wide range can be attributed to a number of variables, including (i) variability of teeth restored (anteriors vs. premolars vs. molars), (ii) anatomical variability for root canals, (iii) variability of statistical significance (study power analysis, sample size), (iv) variability of luting cement, and finally (v) variables in final restorations (direct vs. indirect). Post-debonding failures were the most prevalent, followed by endodontic failures. In general, post-related failure rates were lower than the actual reported failure rates. For instance, Ferrari et al. reported a failure rate of 7–11%, of which only 2.3% were attributed to post-failure (Ferrari, M.et al 2007) Similarly, the 2002 Mannucci et al. study had a 2.5% post-related failure compared to the reported 3.8%. Tooth type and remaining tooth structure (remaining walls) are the primary determinants of tooth longevity.

[0013] There remains a need in the art to improve dental reconstructions of crowns using a post and core support and methods of their installation. It is one object of the present invention to address these areas and to provide an efficient and cost effective dental restoration with fiber post system and methods of their installation. SUMMARY OF THE INVENTION

[0014] This invention is directed to a cost effective, efficient, and easy to implement fiber post system for post and core dental restoration and method of installing the same.

[0015] One aspect of the present invention provides a method of installing a dental fiber post for post and crown dental restorations comprising the steps of: i) providing a fiber post system for post and crown dental restorations including a plurality of fiber posts having at least two distinct diameters for the fiber posts and at least two preformed fiber post lengths, and each post containing a visible depth marker indicative of where the post should be placed above and below root orifice, ii) measuring a root length of the tooth receiving the post and crown dental restoration from a canal orifice of a canal of the tooth to the root apex; iii) selecting a fiber post of the fiber post system based upon the measured root length of the tooth; iv) obturating the canal with gutta percha to the canal orifice; v)reaming the obturated canal with a reaming tool to a depth associated with a length of the selected fiber post below the visible depth marker to form a prepared post space; and vi) placing selected fiber post within the prepared post space to the depth of the visible marker on the selected fiber post with cementing material toAtlas 4 | P a g e Patent Applicationsecure the selected fiber post in position wherein the visible depth marker is at the top of the prepared post space.

[0016] One aspect of this invention provides a fiber post system for dental restoration with the system having a plurality of fiber posts having at least two distinct diameters for the fiber posts and at least two preformed fiber post lengths, and each post containing a visible depth marker indicative of where the post should be placed above and below root orifice, whereby the fiber post selected is configured to be based upon the root length of the specific tooth obturated yielding proper post space preparation apically for cementation and coronally for foundational core build up. The resulting implanted post eliminates or minimizes post manipulation during tooth preparation to create a mono- block of core material around the post during cementation and build up resulting in no disruption of either bond during preparation.

[0017] The fiber post system according to one aspect of the present invention provides wherein the plurality of fiber posts having at least four distinct diameters for the fiber posts and four preformed fiber post lengths. The fiber post system according to one aspect of the present invention provides wherein the visible depth marker indicative ofwhere t h e post should be placed above and below root orifice is marked at the 1 / 3-2 / 3 junction of the fiber post length, and wherein the visible depth marker indicative of where the post should be placed above and below root orifice is a visible line circumscribing the perimeter of the post.

[0018] The fiber post system according to one aspect of the present invention provides wherein the plurality of fiber posts are color coded for distinct post diameters or distinct fiber post lengths, and wherein the color coding is positioned to be covered by an core and crown, and wherein each distinct diameter for the fiber posts is associated with one distinct fiber post length. The fiber post system according to one aspect of the present invention provides wherein the fiber post lengths are 8mm, 9mm, 10mm and 11 mm and the post diameters are 0.6 mm, 0.7 mm, 0.8mm and 0.9 mm.

[0019] One aspect of this invention provides dental restoration having a crown, an core and a fiber post selected from a fiber post system having a plurality of fiber posts having at least two distinct diameters for the fiber posts and at least two preformed fiber post lengths, and each post containing a visible depth marker indicative of where the post should be placed above and below root orifice, whereby the fiber post selected is configured to be based upon the root length of the specific tooth obturated yielding proper post space preparation apically for cementation and coronally for foundational core buildAtlas 5 | P a g e Patent Applicationup. The resulting implanted post eliminates or minimizes post manipulation during tooth preparation to create a mono-block of core material around the post during cementation and build up resulting in no disruption of either bond during preparation.

[0020] These and other aspects of the present invention will be clarified in the description of the preferred embodiment of the present invention described below in connection with the attached figures in which like reference numerals represent like elements throughout. DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Figure 1 is a perspective schematic view of a prior art dental restoration of a crown and post and core system.

[0022] Figure 2 is a perspective schematic partially exploded view of a prior art dental restoration of a crown and post and core system.

[0023] Figure 3 is an exploded view of a dental restoration using a fiber post system of the present invention.

[0024] Figure 4 schematically illustrates a fiber post system having a plurality of fiber posts having at least two distinct diameters for the fiber posts and two preformed fiber post lengths according to one aspect of the present invention.

[0025] Figure 5 schematically illustrates the measure of root length for implementing a dental restoration using a fiber post system of the present invention.

[0026] Figure 6 is a schematic overlay of the root length measurement and a corresponding selected post of the fiber post system of the present invention.

[0027] Figure 7 schematically illustrates placement of a post of the fiber post system of the present invention.

[0028] Figure 8 schematically shows the post and core of the dental restoration of the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] The present invention is directed to a dental restoration 40 having a crown 10, a core 20 and a fiber post 52, 58, 60 or 62 selected from a fiber post system 50 having a plurality of fiber posts 52, 58, 60 or 62 having at least two distinct diameters for the fiber posts 52, 58, 60 or 62 and at least two preformed fiber post lengths, and each post 52, 58, 60 or 62 containing a visible depth marker 54 indicative of where the post 52, 58, 60 or 62 should be placed above and below root orifice 70, whereby the fiber post 52, 58, 60Atlas 6 | P a g e Patent Applicationor 62 selected by the clinician is configured to be based upon the root length 72 of the specific tooth 74 obturated yielding proper post space preparation apically for cementation 76 and coronally for foundational core build up.

[0030] The resulting implanted post 52, 58, 60 or 62 eliminates or minimizes post manipulation during tooth preparation to create a mono-block of core material around the post 52, 58, 60 or 62 during cementation 76 and build up resulting in no disruption of either bond during preparation.

[0031] Figure 3 is an exploded view of the dental restoration 40 using a post 52, 58, 60 or 62 fiber post system 50 of the present invention, while Figure 4 schematically illustrates a fiber post system 50 having a plurality of fiber posts 52, 58, 60 or 62 having at least two, specifically four, distinct diameters for the fiber posts 52, 58, 60 or 62 and at least two, specifically four, preformed fiber post lengths according to one aspect of the present invention. The post 52, 58, 60 or 62 diameter herein is the largest diameter of the circular cross sectional post 52, 58, 60 or 62, as it is typical for the post 52, 58, 60 or 62 to taper in diameter at the distal end as shown. The post length of post 52, 58, 60 or 62 is the length along the longitudinal axis from the proximal end to the distal end of the post 52, 58, 60 or 62. Figure 8 schematically shows the post (generically referenced as number 50) and core 20 of the dental restoration 40 of the present invention.

[0032] A fiber post 52, 58, 60 or 62 within the meaning of this application references a post of a dental restoration 40 formed from fiber composites. It is noted that there are several crucial properties of fiber composites for posts 52, 58, 60 or 62, such as their optical, mechanical, and bonding properties, are determined by the type of fiber reinforcement and matrix used in the posts 52, 58, 60 or 62.

[0033] Both the fibers and the matrix contribute in different ways to the stability of the material forming the posts 52, 58, 60 or 62. The fibers provide stiffness and strength, while the polymeric matrix ensures the integrity of the composite structure. The matrix also distributes and transfers the load between the fibers. The posts 52, 58, 60 or 62 can have either a thermoplastic (linear) or thermoset (cross-linked) matrix. The latter contains dimethacrylate or multifunctional resins, such as epoxy resin and bisphenol A-glycidyl methacrylate (Bis-GMA) and urethane di-methacrylate (UDMA). With their highly cross- linked networks, thermosetting polymers have superior mechanical properties, durability, thermal stability, and chemical resistance to thermoplastics. The fiber accounts for the largest proportion of posts 52, 58, 60 or 62 at about 40–65 volume %. Thus the fiber determines the load-bearing capacity of the structure and significantly contributes to theAtlas 7 | P a g e Patent Applicationmatrix strength and stiffness. Dental posts 52, 58, 60 or 62 may be reinforced with a variety of fibers, such as polyethylene, carbon, glass, and Kevlar (p-phenylene diamine). The fibers may be are utilized with either a unidirectional or a woven orientation. The effectiveness of the reinforcing role of fibers is dependent on a variety of factors, including their orientation, diameter, compatibility, quantity, and impregnation with the matrix resin.

[0034] The fiber post system 50 according to a preferred embodiment of the invention has four distinct diameters for the posts 52, 58, 60 and 62, preferably 0.6 mm diameter for post 52, 0.7 mm diameter for post 58, 0.8mm diameter for post 60 and 0.9 mm diameter for the fiber post 62. The fiber post system 50 according to a preferred embodiment of the invention has four distinct post lengths for the posts 52, 58, 60 and 62, namely 8 mm post length for post 52, 9 mm post length diameter for post 58, 10 mm post length for post 60 and 11 mm post length for the fiber post 62. As noted each post 52, 58, 60 and 62 is marked with a visible indication 54 (visible line extending around the circumference of the circular post 52, 58, 60 and 62) at the 1 / 3 -2 / 3 junction to delineate where 52, 58, 60 and 62 post should be placed above and below root orifice 70.

[0035] The posts 52, 58, 60 and 62 are color coded 56 matching a color coated master reamer. The number shown below the indication 54 in the figures (not on actual posts ofsystem 50) is a distance below the root orifice 70 a n d is the post space dimensionand will be marked on the Pilot reamer and color coated master reamer corresponding to selected post to remove obturated GP and sealer.

[0036] The post 52 of system 50 has a length of 8 mm of which 2.5 mm is above the indicia 54 and 5.5 mm is below the indicia 54, and this post is generally suitable forMaxillary First Premolar, First Molar (Palatal Canal) Mandibular Central, a n d LateralIncisor applications.

[0037] The post 58 of system 50 has a length of 9 mm of which 3 mm is above the indicia 54 and 6 mm is below the indicia 54, and this post is generally suitable for MaxillaryLateral t o Second Molar (Palatal Canal) applications.

[0038] The post 60 of system 50 has a length of 10 mm of which 3.5 mm is above the indicia 54 and 6.5 mm is below the indicia 54, and this post is generally suitable for maxillary Lateral, Central, and Mandibular Canine applications.

[0039] The post 62 of system 50 has a length of 11 mm of which 4 mm is above the indicia 54 and 7 mm is below the indicia 54, and this post is generally suitable for Maxillary Central, Lateral, Canine and Mandibular Canine applications.Atlas 8 | P a g e Patent Application

[0040] The method of installing the dental restoration 40 using a post 52, 58, 60 or 62 of the fiber post system 50 of the invention includes measuring, as shown in figure 5, the approximate root length (RL) 72 from canal orifice 70 of the tooth 74 to be obturated to the root apex using measurement tool obtained within digital radiograph software. Root length measurements 72 are rounded up or down, for example 9.5mm rounds up to 10 mm and 9.25 rounds down to 9.0 mm.

[0041] Based on the tooth 74 to be obturated for endodontic treatment and measured root length 72, then the appropriate sized post 52, 58, 60 or 62 is selected based on a fixed proportion of the measurement 72, namely about 2 / 3 of this length. As noted the posts 52, 58, 60 and 62 are color coded by length (and diameter) with the 8mm post 52 having a color coding 56 of White, the 9mm post 58 having a color coding 56 of Yellow, the 10mm post 60 having a color coding 56 of Red, and the 11mm post 62 having a color coding 56 of Blue. In order to obtain the appropriate post 52, 58, 60 or 62 the root length 72 is divided into approximate thirds (1 / 3 & 2 / 3) for post placement measurements and the proper post 52, 58, 60 and 62 is one having a length approximately 2 / 3 of the root length 72 as shown in figure 6.

[0042] As noted the root length of 13.5 is rounded up and to 14mm and the proper post is post 58 having a length of 9mm. A chart of the ranges of root lengths 72 that are associated with each post 52, 58, 60 and 62 is preferably utilized to simplify the process. As each post 52, 58, 60 and 62 is associated with a given diameter, the chart also effectively correlates a root length 72 to a proper diameter of post 52, 58, 60 or 62.

[0043] The post selected will have approximate 1 / 3 & 2 / 3 demarcation or indicia marking 54 with 1 / 3 of the post 52, 58, 60 or 60 to be positioned above coronal orifice 70 and 2 / 3 below coronal orifice 70. Following post selection the clinician will try the selected post 52, 58, 60 or 62 to insure correct size, and then place post in a secure area for latter installation.

[0044] The clinician will then obturate canal with gutta percha (GP) and sealer to top of orifice with preferred system. Obturation or obturating is known as the step within a root canal when the pulp chamber is filled and sealed with gutta-percha. During obturation, the gutta-percha may be heated and put it in the tooth, compacted, and sealed. The complete and three-dimensional fluid tight seal of the root canal system is critical. Gutta-percha has been most extensively used for years and has established itself as a gold standard. In addition, it has proved itself successful with different techniques of obturation while maintaining its basic requisites. Gutta-perchaAtlas 9 | P a g e Patent Applicationis a dry coagulated sap of a peculiar species of tropical plants. It was first obtained from Sapotaceae family of trees, which are abundant in the Malay Peninsula (South East Asia).

[0045] The clinician uses a pilot reamer using either low speed hand piece at 2000- 5000 rpm or heated instrument with red stopper marked at previously measured 2 / 3 distance down obturated canal from root orifice 70. The clinician will complete postspace with same color coated master reamer as the color 56 of the post 52, 58,60 or 62 selected. The clinician may use an ultrasonic instrument to remove excesssealer and gutta percha on walls of the post space preparation. The clinician may then dry the canal with cotton point and / or air syringe.

[0046] Then the clinician will clean the selected post 52, 58, 60 or 62 with alcohol and treat with a silane coupling agent by applying for 30 seconds and dry with air syringe. The clinician can then treat the post space with preferred dual cured adhesive agent protocol for dual cured core build up resin composite. In other words the cementing material 76 is the same material forming the core 20. It is possible to have the core 20 separate from the cementing material 76 however, the use of compatible dual cured adhesive and composite core material 76 insures adequate bond. The clinician may remove excess bonding agent with cotton point, and air dry adhesive for 10 seconds and light cure 10 seconds or according to manufacturer’s instructions for use.

[0047] The clinician will place dual-cured composite core material 76 into post space preparation. The clinician will place the previously selected post 52, 58, 60 or 62 into position (generally with grasping tool 78) and pump the post 52, 58, 60 or 62 up and down to remove any air entrapment. The clinical positions post 52, 58, 60 or 62 in correct position as shown in figure 7 using indicator 54 as guide and light cure directly over post 52, 58, 60 or 62 for 10 seconds. The clinician can place core build up composite material 76 incrementally no more than 3 mm for each addition and wait 5 minutes for complete dark cure before initiation any preparation.

[0048] The posts 52, 58, 60 and 62 of system 50 provide a pre-calculated proper, proportional relationship between frictional retention and the contact area for the selected post 52, 58, 60 and 62. The diameter and length also optimize fracture resistance of the post 52, 58, 60 and 62. The fit and retention of the selected post 52, 58, 60 or 62 is optimized with proper use of pilot drill and color coded master drills, obtaining or creating a form-congruent root canal for effective post-placement. This ‘form-congruence’ adaptsAtlas 10 | P a g e Patent Applicationthe root canal walls to the selected post 52, 58, 60 or 62 utilizing a thin and even layer of post-root adhesive or cement 76. As the fit between the post 52, 58, 60 or 62 and the root canal is excellent with the system 50, stress will be more evenly distributed along the canal wall during clinical function. Even if the tooth’s canals are oval or irregular in shape, the post space is meticulously reshaped with the pilot drill and color coded master drill to produce a round and form-congruent shape. The conformal shape acts to reduce the cement gap to a minimum and customizing the post 52, 58, 60 and 62 to best fit the root canal shape.

[0049] The cementation material 76 (also used preferably to form the core 20) described herein is conventional in the art and includes various known adhesive bonding. The fundamental principles of adhesive bonding are not part of this invention and involve the use of etchant to create micromechanical adhesion between composite restorations and enamel, as well as the development of an inter-diffusion interface between bonding resin and dentine. The use of a multi-step dentine bonding system is the current preferred method for achieving long-lasting dentin bonding. It may involve applying a hydrophilic primer to etched dentin to permeate the dentinal tubules and collagen fibrils, followed by using a hydrophobic adhesive comprising Bis-GMA and triethylene glycol dimethacrylate TEGDMA. The use of so-called fifth-generation adhesive systems, which combine the primer and adhesive in a single solution have been proposed to simplify the bonding process by reducing it to two rather than three steps. The most recent types of adhesives are referred to as ‘universal’ or ‘all-in-one’ adhesives. These adhesives can perform the functions of etchant, primer, and adhesive within the same solution, and they are compatible with phosphoric acid etching pre-treatment and are suitable for use as self- etching adhesives. In conjunction with self-etching primers, these adhesives are commonly used to bond composite restorations and cores in teeth with root canal fillings as well as fiber and metal posts. Resin-based luting cement can be generally defined as low-viscosity composite materials that comprise a dimethacrylate and oligomer monomer matrix. The filler contents ensure low film thickness. Several monomers with different molecular weights, such as UDMA, Bis-GMA, Bis-EMA, and TEGDMA, are combined to produce a material with a high degree of polymerization and, thus, low shrinkage. Silica fillers and silanated radiopaque glass (zirconia, strontium, or barium) are typically used in concentrations ranging from 30 to 60 percent by volume, with particle sizes ranging from 0.5 to 8.0 ^m. Self-adhesive resin cement is widely used in clinical practice for bonding fiber posts because it reduces nano-leakage and provides a strong bond. It has beenAtlas 11 | P a g e Patent Applicationsuggested that their bond strength could be improved even further with the use of phosphoric acid to pre-condition the surface of the root canal dentin.

[0050] It is apparent that many variations to the present invention may be made without departing from the spirit and scope of the invention. The present invention is defined by the appended claims and equivalents thereto.Atlas 12 | P a g e Patent Application

Claims

What is claimed is:

1. A method of installing a dental fiber post for post and crown dental restorations comprising the steps of: i) providing a fiber post system for post and crown dental restorations including a plurality of fiber posts having at least two distinct diameters for the fiber posts and at least two preformed fiber post lengths, and each post containing a visible depth marker indicative of where the post should be placed above and below root orifice, ii) measuring a root length of the tooth receiving the post and crown dental restoration from a canal orifice of a canal of the tooth to the root apex; iii) selecting a fiber post of the fiber post system based upon the measured root length of the tooth; iv) obturating the canal with gutta percha to the canal orifice; v) reaming the obturated canal with a reaming tool to a depth associated with a length of the selected fiber post below the visible depth marker to form a prepared post space; and vi) placing selected fiber post within the prepared post space to the depth of the visible marker on the selected fiber post with cementing material to secure the selected fiber post in position wherein the visible depth marker is at the top of the prepared post space.

2. The method of installing a dental fiber post according to claim 1 whereinthe visible depth marker indicative of where t h e post should be placed above andbelow root orifice for the selected fiber post is marked at the 1 / 3 -2 / 3 junction of the fiber post length.

3. The method of installing a dental fiber post according to claim 1 whereinthe visible depth marker indicative of where t h e selected fiber post should be placedabove and below root orifice is a line circumscribing the perimeter of the post.

4. The method of installing a dental fiber post according to claim 1, wherein the plurality of fiber posts are color coded for distinct post lengths.

5. The method of installing a dental fiber post according to claim 4, wherein the color coding is positioned to be covered by a core and crown, and wherein each distinct diameter for the fiber posts is associated with one distinct fiber post length.

6. The method of installing a dental fiber post according to claim 4, wherein the fiber post lengths are 8mm, 9mm, 10mm and 11 mm and the post diameters are 0.6 mm, 0.7 mm, 0.8mm and 0.9 mm.Atlas 13 | P a g e Patent Application7. The method of installing a dental fiber post according to claim 1 wherein the reaming tool is selected based upon the selected fiber post.

8. The method of installing a dental fiber post according to claim 1 wherein the cementing material is a dual-cured composite core material.

9. A fiber post system for post and crown dental restorations comprises a plurality of fiber posts having at least two distinct diameters for the fiber posts and at least two preformed fiber post lengths, and each post containing a visible depth marker indicative of where the post should be placed above and below root orifice, whereby the fiber post selected is configured to be based upon the root length of the specific tooth obturated yielding proper post space preparation apically for cementation and coronally for foundational core build up.

10. The fiber post system according to claim 9, wherein the plurality of fiber posts have at least four distinct diameters for the fiber posts and four preformed fiber post lengths.

11. The fiber post system according to claim 10, wherein the visible depthmarker indicative of where t h e post should be placed above and below root orifice ismarked at the 1 / 3 -2 / 3 junction of the fiber post length.

12. The fiber post system according to claim 11, wherein the visible depthmarker indicative of where t h e post should be placed above and below root orifice isa line circumscribing the perimeter of the post.

13. The fiber post system according to claim 11, wherein the plurality of fiber posts are color coded for distinct post diameters.

14. The fiber post system according to claim 13, wherein the color coding is positioned to be covered by a core and crown, and wherein each distinct diameter for the fiber posts is associated with one distinct fiber post length.

15. The fiber post system according to claim 11, wherein the plurality of fiber posts are color coded for distinct post lengths.

16. The fiber post system according to claim 15, wherein the color coding is positioned to be covered by a core and crown, and wherein each distinct diameter for the fiber posts is associated with one distinct fiber post length.

17. The fiber post system according to claim 15, wherein the fiber post lengths are 8mm, 9mm, 10mm and 11 mm and the post diameters are 0.6 mm, 0.7 mm, 0.8mm and 0.9 mm.Atlas 14 | P a g e Patent Application18. The fiber post system according to claim 10, wherein each post length differs from the next closest post length by 1 mm.

19. The fiber post system according to claim 18, wherein each post diameter differs from the next closest post diameter by 0.1 mm.

20. A dental restoration having a crown with a post and crown support wherein the post is a fiber post selected from the fiber post system according to claim 8.Atlas 15 | P a g e Patent Application

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