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Aim: The aim of this study was to compare the fitting accuracy of custom-made metal posts and cores fabricated by half-digital and milling technique to that of conventional cast posts fabricated by direct technique. Methods: Sixteen extracted single-rooted teeth were endodontically treated followed by post space preparation. A direct resin post and core pattern was made for each tooth and used for the fabrication of two posts (n = 16). Each post resin pattern was digitized with a laboratory scanner and used for the fabrication of a milled cobalt–chrome (Co–Cr) alloy post, while the direct resin pattern, after scanning, was cast in a Co–Cr alloy to produce a cast post. Each post was seated on its respective tooth and evaluated using microcomputed tomography. The following variables were evaluated: total space volume between the post and root canal, the volume and distance of the apical gap between each post and the remaining apical root canal filling, as well as the distance and surface area of the space between the post and lateral root canal wall at four determined points along the length of each post. Results: The results revealed that half-digital and milled posts had a statistically significantly higher total space volume (p < 0.05), apical gap volume (p < 0.02) and distance (p < 0.02), as well as a higher surface area of space between the post and root canal wall at the cervical area as compared to the cast post (p < 0.05). Conclusions: This study demonstrated that the fitting accuracy of cast posts was more accurate than posts fabricated with half-digital and milling technique. [ABSTRACT FROM AUTHOR]

It is common to detect a gap between the apical portion of the post and the most coronal part of gutta-percha in a root canal during post and core treatment in endodontically treated teeth. It may compromise the seal that gutta-percha material provides in the root canal filling, leading to apical leakage, which is often thought to be one of the most common causes for failure of endodontic treatment. The prevention of apical leakage to achieve a complete apical seal and its effect on periapical health of endodontically treated teeth of post and core in long term clinical research remains unanswered. Post and core treatment were provided to 100 patients by undergraduate students in the year 2016–2017. A total of 70 patients in all were called back to the Prosthodontic Clinic for follow-up care after 4 years to assess the clinical result in terms of the gap between the post-operative and residual gutta-percha. The cemented posts were divided into three groups depending on the space between the cemented post end and the remaining gutta-percha: group I revealed no gaps, group II revealed gaps between >0.1 and 1 mm, and group III revealed gaps more than 1 mm. The periapical index (PAI) was used to determine the apical condition of each tooth. Chi-square test was used for evaluating the data, and a p-value of 0.05 was considered statistically significant. A total of 28.6% post and core treated teeth were found diseased while 71.4% teeth were found normal. In group I, 90% of the teeth and in group II, 66.7% of teeth were evaluated as normal; however, in group III, 41.2% teeth were found diseased. In endodontically treated teeth restored with a post and core, a gap between the apical end of the post and the coronal section of the residual gutta-percha was associated with a greater prevalence of disease. The post and core treatment by undergraduate students achieved a clinically acceptable outcome in terms of the gap between the post end and the remaining gutta-percha. [ABSTRACT FROM AUTHOR]

Objectives. The aim of the present study was to analyze comparatively, through the finite element method (FEM), the biomechanical behavior of different types of devices used to increase the resistance of restorations on endodontically treated teeth, upon the experimental application of a force of 350N. Materials and methods. We studied comparatively three types of posts, respectively: fiberglass post, cast post from Cr-Co-Mo alloy and prefabricated titanium post. Three irretrievable extracted teeth for periodontal reasons were endodontically treated and then specifically prepared for cementation of this devices. The teeth were scanned at a radio-diagnostic center, and the obtained DICOM files were processed with MIMICS and 3-matic and then subjected to finite element analysis with ANSYS. Results. From the 48 simulations carried out for the case of all-ceramic crown coverage, the use of titanium post is associated with 25 situations in which maximum or minimum values appear, the use of cast post presents 12 situations in which maximum or minimum values are developed, the use of fiberglass posts is associated with 10 simulations where maximum or minimum values occur, and in one case the deformations are equal. Regarding the use of the zirconium oxide crown, the results are comparable. Conclusions. The presence of zirconium oxide crowns generally produces less valuable stresses and deformations at the level of the components. The stress and strain values are lowest when using fiberglass posts, followed closely by cast post and far behind by titanium post. In all simulated situations, the limit values of stresses and strains are mostly recorded at the tooth root, which is susceptible to fracture in case of parafunctional forces, followed by the three devices themselves and the covering crowns. [ABSTRACT FROM AUTHOR]

Introduction: Endodontically Treated Teeth (ETT) are most likely to get fractured, if it is left unrestored compared with the vital teeth due to the loss of tooth structure and reduced modulus of elasticity. Aim: To gain insight into the rationale for choice of endodontic posts and the different endodontic post systems currently used by dental practitioners in western region of Saudi Arabia. Materials and Methods: For this survey-based study, a questionnaire was designed consisting of eight questions to assess the details of why, when and how general practitioners restore ETT and to determine contemporary use of endodontic post from 1st of November 2018 till the end of January 2019. This questionnaire was sent online to 250 private dental practitioners in western region of Saudi Arabia, out of which 202 participants responded. Data was entered in the excel sheet. Descriptive statistics like frequency and proportion was calculated for qualitative data. Results: This study included 202 participants with the mean age group of 25-50 years, out of which 108 (53.4%) male participants and 94 (46.5%) female participants. 120 (59%) of the study sample were general practitioners and 82 (41%) of them were specialists. A total of 60 (29.70) of the study sample were into general practice, reported restoring ETT with post and core followed by the crown, whereas, 30 (14.85%) of them did the crown without post, 15 (7.42%) of them completed restoration with composite and 15 (7.42%) of them did buildup with post and core. An 82 (40.59%) of the study sample who were specialists, reported restoring ETT with post and core build-up and then proceed with crowns. An 80 (39.60%) of the study sample were into general practice, reported using prefabricated fiber post whereas, 23 (11.38%) of them using cast post and 17 (8.41%) of them using prefabricated metal posts. 72 (35.64%) of the study sample were specialists reported using prefabricated fiber posts and 10 (4.95%) of them used cast metal post. Conclusion: Based on the results of the study, it can be concluded that majority of the participants practiced reinforcement of ETT by using fiber posts with resin cements followed by crowns. [ABSTRACT FROM AUTHOR]

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Objective: Clinical studies show a high failure incidence after years of service of endodontically treated premolars, when restored with post-core crowns, especially those with short posts or deficient ferrules. The reason for this can be a deterioration of the luting cement around the post by fatigue from functional loading. In particular, the anatomy of premolars may frequently be incompatible with the application of long endodontic posts. The aim of this study was to evaluate the influence of fatigue loading on the quality of the cement layer between posts with restricted lengths and the root canal wall in premolars. As the stiffness of posts may affect the outcome, post-and-core systems with varying post stiffness were selected. Method and materials: Four types of post-and-core systems were selected for this study: three prefabricated post systems combined with a resin composite core material and one cast post and core. The three prefabricated posts were titanium posts (Tenax), quartz-fiber posts (Aestheti-Post), and quartz-coated-carbon-fiber posts (Aestheti-Plus). The post-and-core restorations were made on single-rooted, human, maxillary premolars from which the coronal sections were removed at the level of the proximal cementoenamel junction. Following endodontic treatment, a cast post and core (post length 6 mm) was prepared for each tooth individually (direct method) and cemented into the root canal with chemical cure Panavia 21 TC. The prefabricated posts were directly cemented in the root canal and then, after applying a dual-cure adhesive (Clearfil Photobond), built up with a core build-up composite (Clearfil Photocore). For each group (n = 8), half of the specimens were exposed to fatigue loading (105 load cycles) almost perpendicular to the axial axis (85 degrees), while the other half was used as the control. Three parallel, transverse root sections of 1.5-mm thickness, were cut from each specimen. These sections were examined by scanning electron microscopy (SEM) to evaluate the cement integrity, while the retention strength of the cemenied post sections was determined with a push-out test. Results: Fatigue loading did not cause separation o! the buildups from the roots or affect the push-out strength. On a univariate level, only SEM evaluation showed significant differences between the types of post, fatigue loading, and between the levels of root sections. The cement integrity with the titanium post was significantly less than with the other three systems, which did not differ among themselves. The differences could not be explained by differences in stiffness between the posts. Conclusion: A composite core build-up material bonded to the dentin and supported by quartz-fiber posts or quartz-coated-carbon-fiber posts, cemented with adhesive cement like Panavia 21 TC, may be a viable alternative for the conventional cast core. (Quintessence Int 2004,35:657-667) [ABSTRACT FROM AUTHOR]

The article addresses the difficulty of restoring a grossly carious molar tooth, where very little tooth structure is left after caries excavation. When enough sound tooth structure is missing for satisfying the ferrule effect, a clinician can follow this technique and easily restore such teeth. A step by step procedure, including instrumentation and materials and a new impression technique, is described in detail, with clinical photographs. This technique results in the fabrication of a robust and extremely retentive post and core on which to place fixed prosthodontic restorations. A 2 and half year study showed that the tooth well in function with no signs of any problem. The author has restored around many decayed molars using this technique. Over a period of three years, no failure was reported. With an increasing demand on the dentist for restoring a structurally compromised teeth, this technique provides the patients with a robust prosthodontic solution. [ABSTRACT FROM AUTHOR]

Deger S, Akgüngör G, Caniklioglu B. An alternative method for fabricating a custom-made metal post with a ceramic core. Dent Traumatol 2005; 21: 179–182.© Blackwell Munksgaard, 2005.The restoration of anterior non-vital teeth with metal posts and cores and all-ceramic restorations may lead to compromised esthetics because of the semitranslucence of ceramics and the metallic color of the underlying post and cores. This article presents a technique that combines the optical properties of ceramic cores with the mechanical properties of custom-made cast metal posts. The technique involves heat pressing of the core from leucite-enriched glass-ceramic to the underlying custom-made metal post and may provide additional esthetic benefit for anterior teeth especially with little remaining coronal dentin and with small root volume. [ABSTRACT FROM AUTHOR]