Post-retained Crowns Research Articles

Influence of post placement on single unit full coverage restorations in endodontically treated teeth - A systematic review

The aim of this systematic review is to analyse the effect of post placement on single unit full coverage restorations in endodontically treated teeth. Published articles related to post placement on single unit full coverage restorations in endodontically treated teeth which includes original research and literature review from databases such as PubMed, Scopus, Cochrane, Ovid Medline etc., were taken into the study for review. Articles from 2002 to 2023 were included. Two authors independently extracted data and assessed the quality of the selected studies.Six studies involving 991 patients were analyzed in this systematic review, which comprised 229 anterior and 910 posterior teeth. The risk of failure or the survival rate was associated with the teeth that had no post placement when the number of coronal walls was less than two. When three or four coronal walls present the success or survival rate seem to be higher with the post placement. Post-retained crowns are better, post-free crowns may be considered when three or four tooth walls are still present, whereas teeth with one or two remaining walls may be better candidates for post-retained crowns. When the ferrule is absent, prosthetic components may be explored

Survival of Endodontically Treated Maxillary Anterior Teeth with Aesthetic Post-Restoration: A Prospective Intervention Study

Introduction: There is much debate over the best choice of restorative material and the placement method for the most successful treatment. Many teeth that have undergone endodontic treatment may not have enough structure to support a restoration or crown. To improve retention for the restorative material, ferrule may be used. Adhesive techniques have transformed the way we restore teeth after root canal treatment, starting with the shift from using cast post-and-core to using fibre post. The use of fibre-reinforced posts has been found to prevent irreparable root fractures thereby improving the longevity of the treatment. Aim: To compare two different types of aesthetic fibre posts for 12 months. Materials and Methods: A prospective interventional study was carried out in the Department of Prosthodontics, Manav Rachna Dental College (Faridabad) for a period of 12 months from Nov 2022- Oct 2023. Forty participants with single rooted, endodontically treated, maxillary anterior teeth in the age bracket of 15-55 years, both males and females of the north Indian population were included in the study. Teeth were selected where a post-retained crown was indicated and post space was prepared using a piezo reamer drill at 5000 rpm. At least 4 mm of obturation is left in the canal to maintain the apical seal. Furthermore, Zircon-enriched silicon fibre and glass fibrereinforced posts were cemented into the prepared post space. Metal-ceramic crowns were cemented and baseline periapical radiographs were obtained. At the interval of one month, three months, six months and one year, the patients were evaluated. The Fischer’s exact test was utilised to establish the association between categorical variables and the level of significance (p-value <0.05). Results: One year follow-up revealed no failures in crown movement when evaluated under finger pressure, recurrent caries, or root fractures. One case of glass fibre-reinforced post showed a fracture of the post and another case of glass fibre post showed periapical radiolucency at 6-month intervals on clinical and radiographical examination which was significant when compared to Zircon-enriched silicon fibre post group (p-value=0.02). Conclusion: Both aesthetic fibre-reinforced post systems used in single-rooted upper anterior teeth demonstrated similar success rates in restoring root canal treated teeth.

Effect of Ferrule Design on Stress Distribution of Maxillary Incisor Rehabilitated with Ceramic Crown and PEEK Post–Core Material: A 3D Finite Element Analysis

Endodontic-treated teeth with massive degrees of coronal tissue loss usually require rehabilitation with post-retained unitary crowns. This study aimed to evaluate the effect of ferrule design on the stress distribution of maxillary incisors rehabilitated with zirconia crowns using finite element analysis. Six three-dimensional models were generated according to the presence and location of ferrule (No Ferrule, Buccal Ferrule, Lingual Ferrule, Buccolingual Ferrule, and Full Ferrule). The post–core materials tested were Nickel–chromium (NiCr) and Polyetheretherketone (PEEK). A static load of 100 N at a 45-degree angle on the Lingual surface, in a region 2 mm below the incisive ridge, was applied. Von Mises stresses and contour plots of all of the models were collected and analyzed. A lower and more uniform stress distribution was observed in the Full Ferrule model compared with the remaining models. A reduction of 72% in the von Mises peak stresses was observed in the root when comparing the Full Ferrule and No Ferrule models, both with PEEK post–core material. In conclusion, the presence of an incomplete ferrule is beneficial to the stress distribution in restored post-retained crowns. The use of PEEK for post–core structures reduces the stress concentration on the posts, reducing the predisposition to irreparable root fracture.

Cost-effectiveness of post-retained crowns

Cost-effectiveness of post-retained crowns

Cost-effectiveness of Different Post-retained Restorations

ObjectivesDentists can choose between metal and fiber post systems to provide post-retained restorations. The risk of tooth loss and other complications differs between different post systems, as do the initial treatment costs. We aimed to assess the cost-effectiveness of (1) cast metal (MC), (2) preformed metal (MP), (3) glass fiber (GF), and (4) carbon fiber (CF) post-retained restorations. MethodsA mixed public-private payer's perspective within German healthcare was taken. Risks of complications were extracted from systematic reviews. Costs were estimated by using fee items and 2016 material costs. A Markov model was constructed to follow up an endodontically treated molar receiving a post-retained crown in an initially 50-year-old patient during his lifetime. Monte Carlo microsimulations were performed to assess lifetime costs and tooth retention time. ResultsMPs were least costly (€692€), retaining teeth for 26.7 years. GFs were more costly (€745€), retaining teeth for 27.6 years. MCs were minimally more effective but also more costly than GFs (€774€). CFs were less effective and most expensive (€825€, 26.7 years). For payers willing to invest more than €60€ per tooth retention year, GF was cost-effective. Payers willing to invest an additional €670€ found MC to be cost-effective. These findings were found robust in sensitivity analyses. ConclusionsFor payers not willing to invest additional money for longer tooth retention, MP seemed most suitable to retain restorations. For payers with additional willingness to pay, GF seemed suitable, retaining teeth for longer. MC was only cost-effective under very high willingness to pay. CF is not recommendable on the basis of their cost-effectiveness.

Failure of single-unit restorations on root filled posterior teeth: a systematic review.

This systematic review investigated the failure rate of conventional single-unit restorations in root filled posterior permanent teeth. Two reviewers independently applied eligibility criteria, extracted data and assessed the quality of the evidence of each included study according to the Cochrane Collaboration's procedures for randomized control trials (RCTs) and the STROBE criteria for observational studies. The MEDLINE (via Ovid), EMBASE (via Ovid), Cochrane Oral Health Group Trials Register and CENTRAL (via Cochrane Library) databases were searched electronically (January 1993 to week 1, February 2015). This was complemented by an additional hand search of selected journals and the references of relevant studies. Clinical studies published on root filled single-unit restorative treatments with a mean follow-up period of at least 3years were selected. The outcome measured was clinical or radiological failure. Overall, the four RCTs and the single observational study included were of low and high quality, respectively. Therefore, a meta-analysis was not possible. The pooled mean failure rates were reported according to the type of treatment and remaining coronal tooth structure. The current evidence suggested that the failure rates of the treatments may depend on the amount of remaining tooth structure and type of treatment. Post-retained crowns were associated with the most favourable outcome in teeth with one to two remaining coronal tooth wall(s), whereas post-free crowns were superior when greater tooth structure was available. Restorations in teeth without ferrules had such a high rate of failure that other treatment options should be considered.

Comparative evaluation of the metal post and fiber post in the restoration of the endodontically treated teeth

Background: Post-retained crowns are indicated for endodontically treated teeth (ETT) with severely damaged coronal tissue. There are still controversies for the most suitable choice of restorative material and the placement method that will result in the highest success rate. This clinical study compares the metal post and fiber post ins the restoration of the endodontically treated teeth. Materials and Methods: Forty endodontically treated and indicated for the post and core were selected for the study and divided into 2 groups equally. In, one group patient's teeth were restored by metal post, while other group patient's teeth were treated by fiber post. Comparative evaluation was done on follow-up of the patients on the basis of selected clinical and radiographical criteria. The results were compared using student's t test with the help of IBM SPSS Statistics 20. Results: More number of failures was noted in patients whose teeth restored with the metal post as compared to those of the fiber post, both clinically as well as radiographically. (Student's t test, P

'The last post?': assessment of the failing post-retained crown.

Failure of a post-retained restoration can provide a challenge to the general dental practitioner (GDP) in terms of diagnosis, treatment planning and communication with the patient. The cause of failure must be identified, and a thorough assessment of the restoration, remaining tooth and its functional and aesthetic demands carried out in order to plan treatment to provide the most reliable result. Clinical Relevance: This article discusses the assessment of failing post-retained crowns, with discussion of reasons for failure, thereby assisting the GDP in decision-making and treatment planning for such teeth.

Prevalence of periradicular periodontitis in a Scottish subpopulation found on CBCT images

To investigate the prevalence of periradicular periodontitis (PRP) using cone-beam computed tomography (CBCT) scans in a retrospective cross-sectional epidemiological study in a Scottish subpopulation. Of the 319 CBCT scans performed at Dundee Dental Hospital between November 2009 and July 2012, 245 dentate scans of patients over 18 years of age were included and 3595 teeth examined. Odds ratios were calculated, and the association between root filling and posts with PRP was determined. Radiological signs of PRP were detected in 209 teeth (5.8%) in 96 patients (male = 53, female = 43) of which 145 (69.4%) were measurable and 64 (30.6%) appeared as periapical widening. Most lesions were seen in the 46-55-year age group and in maxillary anterior teeth (35.4%); 47.4% (n = 81) of the total root filled teeth (n = 171) had PRP. Of the root filled teeth with lesions, approximately half (50.6%) had an inadequate root filling. Teeth with crowns, but not root filled, accounted for 17.7% of PRP. Periapical changes were detected on a high proportion of teeth with post-retained crowns (70.7%). The presence of a root filling was significantly associated with PRP (z = 17.689 P < 0.0001; odds ratio 16.36 < 23.17 < 32.83, 95% CI) and the presence of a post (z = 10.901 P < 0.0001; odds ratio 21.36 < 41.8021 < 81.78, 95% CI). The prevalence of PRP in a Scottish subpopulation was 5.8%. The presence of a root filling or a post-retained crown was significantly associated with the presence of PRP as determined by CBCT scans. The prevalence of periradicular disease in root filled teeth remains high in the Scottish population.

Randomized clinical study comparing metallic and glass fiber post in restoration of endodontically treated teeth.

Post-retained crowns are indicated for endodontically treated teeth (ETT) with severely damaged coronal tissue. Metallic custom and prefabricated posts have been used over the years, however, due to unacceptable color, extreme rigidity and corrosion, fiber posts, which are flexible, aesthetically pleasing and have modulus of elasticity comparable with dentin were introduced. To compare clinical performance of metallic and glass fiber posts in restoration of ETT. 40 ETT requiring post retained restorations were included. These teeth were randomly allocated into 2 groups. Twenty teeth were restored using a glass fiber-reinforced post (FRP) and 20 others received stainless steel parapost (PP), each in combination with composite core buildups. Patients were observed at 1 and 6 months after post placement and cementation of porcelain fused to metal (PFM) crown. Marginal gap consideration, post retention, post fracture, root fracture, crown fracture, crown decementation and loss of restoration were part of the data recorded. All teeth were assessed clinically and radiographically. Fisher's exact test was used for categorical values while log-rank test was used for descriptive statistical analysis. One tooth in the PP group failed, secondary to decementation of the PFM crown giving a 2.5% overall failure while none in the FRP group failed. The survival rate of FRP was thus 100% while it was 97.5% in the PP group. This however was not statistically significant (log-rank test, P = 0.32). Glass FRPs performed better than the metallic post based on short-term clinical performance.

Stress analysis of endodontically treated teeth restored with post-retained crowns: A finite element analysis study

The authors conducted a study to analyze the stress concentration areas in a tooth restored with a post-retained crown under various conditions.The authors constructed a three-dimensional finite element model describing a maxillary second premolar restored with an all-ceramic crown supported by a titanium post and a resin-based composite core. They applied static vertical and horizontal loads of 100 newton to the cusp tip of the crown and recorded Von Mises and tensile stress values. The variables investigated were the presence of the post, coronal and apical post extensions, post diameter, post shape, and post and core material.The study results showed that horizontal loading generated higher levels of stress than did vertical loading. The greatest stress levels were concentrated at the cervical region and at the post-dentin interface in all models. Under both loads, a higher modulus of elasticity of the post material and a wider post diameter were associated with increased stress values at the post-dentin interface. Reduction of the post extension above the level of bone was associated with increased dentinal stresses near the apex of the post.Although endodontic posts provide retention for coronal restorations, they result in dentinal stress values higher than those of crowns without posts. Posts that had a similar modulus of elasticity to dentin and smaller diameters were associated with better stress distribution. Resting coronal restorations on sound dental tissues affected stress distribution more than did the core material or the length of the coronal post extension.Many factors influence the distribution of stress within dentin and, consequently, the fracture resistance of teeth restored with post-retained crowns. Clinicians need to keep these factors in mind when performing endodontic procedures that involve placement of post-retained crowns to ensure optimal success.

Permanent mimic musculature and nerve damage caused by sodium hypochlorite: a case report

Sodium hypochlorite is often used as an irrigation solution during routine endodontic treatment. Before recementation of a post-retained crown on the upper left lateral incisor, the root canal was irrigated with sodium hypochlorite. There was no root filling in the root canal, and the apex was open after an earlier apicoectomy. Sudden pain with swelling of the left face side occurred during root canal rinsing. Three years later, a paraesthesia still remained in the affected region and a paralysis of some mimic muscles in this region was observed. There were no signs of improvement.

Tensile bond strength of glass fiber posts luted with different cements

Proper selection of the luting agent is fundamental to avoid failure due to lack of retention in post-retained crowns. The objective of this study was to investigate the tensile bond strength and failure mode of glass fiber posts luted with different cements. Glass fiber posts were luted in 40 mandibular premolars, divided into 4 groups (n = 10): Group 1--resin-modified glass ionomer RelyX Luting; Group 2--resin-modified glass ionomer Fuji Plus; Group 3--resin cement RelyX ARC; Group 4--resin cement Enforce. Specimens were assessed by tensile strength testing and light microscopy analysis for observation of failure mode. The tensile bond strength values of each group were compared by ANOVA and Tukey test. The significance level was set at 5%. The failure modes were described as percentages. The following tensile strength values were obtained: Group 1--247.6 N; Group 2--256.7 N; Group 3--502.1 N; Group 4--477.3 N. There was no statistically significant difference between Groups 1 and 2 or between Groups 3 and 4, yet the resin cements presented significantly higher tensile bond strength values than those presented by the glass ionomer cements. Group 1 displayed 70% of cohesive failures, whereas Groups 2, 3 and 4 exhibited 70% to 80% of adhesive failures at the dentin-cement interface. We concluded that resin cements and glass ionomer cements are able to provide clinically sufficient retention of glass fiber posts, and that glass ionomer cements may be especially indicated when the application of adhesive techniques is difficult.

Radiographic Assessment of Post-retained Crowns in an Adult Jordanian Population

The objective of this study was to radiographically assess and compare the quality of post-retained crowns fabricated at the Dental Health Centre of the Jordan University of Science & Technology (JUST). Study data were collected in 2002 from existing dental records for all patients receiving treatment with post-retained crowns between October, 1997 and June, 1999. The posts were assessed radiographically to evaluate various aspects of the quality of post-retained crowns. All 129 posts were fabricated in the dental school. The most-frequently restored teeth were the maxillary incisors (38.8%). Sixty-two percent of the posts were tapered, while 38% were parallel-sided. The mean length of the posts was 0.95 mm (SD 0.41) with a range between 0.22-2.85 mm. Caries was diagnosed radiographically in 10.8% of cases with lesions located on root surfaces in 64.3% of them, while 35.7% of lesions were within the root canal. Three posts (2.3%) were deviated from the line of the root canal in the mesio-distal plane. No evidence of root filling was found in 2.3% of the cases. In the remainder of teeth 15.5% had gutta percha extended to the radiographic apex of the tooth, while 59.7% fell 0.5-1 mm short of the radiographic apex. Gutta-percha was extruded beyond the apex in 22.5% of the teeth. Space between the end of the post and the root filling was found in 22.2%. The percentage of canals with apparently completely healthy periapical tissue was 51.2%. In the rest of the cases 34.8% had areas of radiolucency at or near the root apices and 14% demonstrated widening of the periodontal space around the root apex. Root resection had been completed in 2.3% cases. Signs of external resorption were apparent in one case (0.78%). The standards of the treatment of the endodontically treated teeth made at the dental hospital were satisfactory but could be improved by a controlled academic supervisory environment and a strict scientific approach to fixed prosthodontics within the dental school.

A clinical report of 85 fractured metallic post-retained crowns.

To determine any patient, technique or material factors that were significantly associated with post fracture in metallic post systems. Eighty-five fractured metal posts were retrieved over a 5-year period from a total of 84 patients who attended a dental hospital for treatment. A record was kept of the patient's dentition to identify the tooth with the fractured post, the number of teeth present, the excursive guidance scheme and the likely post design and material. Radiographs of 67 of these teeth were available. The presence or absence of a periapical lesion was noted as was the quality of the root filling. Maxillary lateral incisors, followed by maxillary centrals were associated with most of the fractured posts. The median survival to fracture was 36 months. The number of teeth in the dentition had a mode of 28. The most commonly fractured post design was a serrated and parallel design with an average diameter of 1.2 mm at the site of fracture. Apical lesions were found in 67% of the teeth with radiographs. Only 12% of teeth with a 'good' apical filling as opposed to 55% with a 'poor' apical filling had apical lesions. . Maxillary lateral incisors, followed by maxillary central incisors are at greatest risk of having a fractured metallic post. . Having a large number of teeth in the dentition or an adequate length of post was not protective against metallic post fracture. . Teeth with fractured post-retained crowns had a high incidence of apical lesions.

Technical standard of root canal treatment in an adult Scottish sub-population.

To examine the periapical status, technical standard and frequency of root canal treatment in an adult population in Scotland. Examination of full-mouth periapical radiographs from 340 consecutive adult patients (8420 teeth) attending Glasgow and Dundee Dental Hospitals for clinical examination. Position and quality of the root fillings were assessed together with signs of periradicular radiolucencies. The influence of the type of coronal restoration was also assessed. Pathologies associated with impacted third molars and outcomes following surgical removal of third molars. 54% of the patient sample had root filled teeth. 5.6% of the teeth examined radiographically had root fillings, and of these, 58.1% had radiographic signs of periapical disease. 41% of the patients had at least one non-root canal treated tooth with periapical disease. 77% of teeth with post-retained crowns had evidence of periapical pathology. Root fillings judged to be adequate radiographically had a reduced incidence of radiolucencies. Teeth obturated beyond the apex had more radiolucencies than those obturated flush with or within 2 mm of the radiographic apex. A high proportion of post-retained crowns were associated with periapical pathology. There is a substantial future need both for root canal treatment and for standardised treatment methods.

The evaluation of post‐retained crowns using a custom designed fatigue machine

There are many published reports of static tests on dental materials that are required to perform clinically under a range of load amplitudes and cyclic frequencies. There are fewer reports in the dental literature of fatigue tests on dental structures and materials, and these are reviewed in this paper along with a description of the design, manufacture and commissioning of a machine which can apply chosen cyclic load/time characteristics up to a maximum amplitude of 700 N and frequency of 5 Hz. The machine design is not specific to particular test specimens but is widely applicable within dental materials testing. The machine is being used for a continuing study of post-retained crowns, cemented with glass-ionomer cement. The planning of fatigue tests and the interpretation of results is discussed with reference to the experience of previous authors, and it is concluded that a survival analysis approach offers a means of understanding materials' performances. The initial results from a random, blocked comparison of three glass-ionomer luting cements indicated that cyclic loads can be identified to give a 50% survival probability for specimens. It is expected that loads experienced in vivo have lower amplitude than those applied in this study, however, such loading cycles have been chosen to facilitate material comparisons. It is concluded that gaining significant results under laboratory fatigue conditions is difficult, but that they may usefully complement clinical trials.

A radiographic study of post-retained crowns in patients attending a dental hospital.

A total of 327 post-retained crowns were examined radiographically and a number of features were assessed including the length of post, length of remaining root filling, periapical condition, fit and angulation of the post and quality of root filling. The post length was equal to or greater than that of the crown in only 34% of cases. Although the majority of posts fitted well laterally, 43% did not extend longitudinally as far as the end of the prepared post hole. Some 20% deviated from the line of the root canal but the number of actual lateral perforations was small. A total of 47% of the teeth had areas of radiolucency around the root apices. A majority of root fillings were judged to be unsatisfactory and there was no radiographic evidence of any root filling at all in nearly 10% of cases.

A semi-empirical model for prediction of how post-retained crowns will fail under compressive loading.

The aim of this in vitro study was to determine the relative contributions to retention of the different components of the post-retained crown and the mode of failure when the crown was loaded at 50 degrees to the vertical (i.e., in an apical direction). Failure was initiated in all the specimens as a rotation of the crown about a point on the labial surface of the root at the crown-root interface with pull-out of the post. A semi-empirical model was developed to explain this mode of failure. From experimental results, it was noted that the retention provided by the post was the most significant factor in the equation. However, large variation in the maximum forces recorded from pull-out tests on 40 posts suggested that the glass-ionomer cement was acting in the manner of a brittle composite material whose failure may be attributed to defects in the structure causing stress concentrations. The probability of survival at each ultimate strength recorded experimentally was plotted for comparison with the curve generated by the derived Weibull function. Close agreement was noted. Thus, for any given force applied compressively at 50 degrees to the vertical to a post-retained crown of known dimensions, it is possible, by use of the described equation, to calculate the force, P, applied to the post. This value of P may then be inserted into the Weibull equation to give the probability of the crown failing under that applied force.

An in vitro evaluation of a prototype CFRC prefabricated post developed for the restoration of pulpless teeth

Carbon fibre reinforced carbon (CFRC) in the form of a prefabricated post has recently been developed and is theoretically acceptable for consideration in an endodontic post-retained crown system. This study compared four different types of postcore system cemented into 40 extracted anterior human teeth. The test groups consisted of CFRC posts cemented with a composite resin luting agent, and used with either a cast gold alloy core (Group B) or a composite resin core (Group C). Two existing post-core techniques were used as controls for comparison with the CFRC groups. One control was a prefabricated wrought precious alloy post having a cast gold alloy core, and cemented with zinc phosphate cement (Group A). The other was a prefabricated stainless steel post with a composite resin core, and cemented with a composite resin luting agent (Group D). All specimens were restored with a gold alloy crown and tested to failure with an obliquely applied compressive load at 130 degrees in an Instron using a cross-head speed of 5 cm min-1. The results showed that post-retained crowns using a prefabricated CFRC post exhibited properties comparable with, and in some cases better than, those of existing prefabricated posts. The mode of failure of specimens restored with a CFRC post was more favourable to the remaining tooth tissue than was that of specimens restored with a metallic post.