Comparison of fracture resistance of primary incisor teeth restored with glass fiber post and reversed-oriented metal post - An in vitro study.

Background: This in vitro study aimed to compare the fracture resistance of fiber post and reversed-oriented metal post in the restoration of severely decayed primary incisors. Materials and Methods: In this in vitro study, forty extracted human primary incisors were sectioned horizontally 1 mm above the CEJ and randomly divided into four groups - Group 1: Central incisors restored with reverse-oriented metal post, Group 2: Lateral incisors restored with reverse-oriented metal post, Group 3: Central incisors restored with fiber post, and Group 4: Lateral incisors restored with fiber post. The coronary portion of the teeth was then restored with nanohybrid universal composite. The fracture resistance was measured using universal testing machine. The type of fracture was determined by employing a stereomicroscope. Data were analyzed using two-way ANOVA test. The level of significance was considered at P < 0.05. Results: The mean fracture resistance of glass fiber posts (208.00 ± 73.19) was higher than the reverse-oriented metal posts (190.37 ± 56.36); however, there was no significant difference between any of the groups (P = 0.353). Conclusion: Within the limitations of this study, it can be concluded that both types of posts studied in the present research can be successfully used in the restoration of severely damaged primary incisors.

Three-Dimensional Finite Element Study of Endodontically Treated Maxillary Central Incisors Restored Using Different Post and Crown Materials.

BACKGROUND/PURPOSE: Restoring endodontically treated teeth is a common problem in dental practice. Post and core restorations are one of the major options in the rehabilitation of these teeth. However, there is no final decision regarding the best material or technique to be used with these restorations. So, this study aimed to evaluate the effect of different post and crown materials on the biomechanical behavior of restored maxillary central incisor using the finite element method. MATERIALS AND METHODS: A total of 10 3D models of endodontically treated maxillary central incisors restored with two prefabricated posts and three custom-made posts were modeled and grouped according to post material (gold, nickel-chrome, zirconia, and glass fiber) and crown material (lithium disilicate, and zirconia). Finite element analysis was conducted, and stress distribution was evaluated using von Mises criteria. RESULTS: Both crown materials showed stress concentration at the force application site mainly on the intaglio palatal surface of the crown. However, more stress values were observed within zirconia crowns. All posts showed stress concentration at their buccal sides. However, more stress values were observed in zirconia and metal cast posts compared to glass fiber posts that transfer more stress to root dentin. CONCLUSIONS:  Post and crown materials affect the stress distribution in the tooth-restoration complex. Using high elastic modulus posts slightly decreased stress in root dentin despite concentrating more stress within their structure. However, glass fiber posts resulted in more homogenous stress distribution in the tooth-restoration complex. Crown material did not influence the stress distribution in root dentin. Custom-made posts decreased stress within crowns, regardless of the crown material. However, more stress values were observed within zirconia crowns. Custom-made zirconia posts and cores showed a similar stress distribution as non-precious metal cast posts, so they may be used as a suitable option where esthetic is desirable.

A Case Report on the Rehabilitation of Severely Worn Teeth Using a Custom-Made Cast Post.

Posts have been suggested to strengthen weak endodontically treated teeth against intra-oral forces by transmitting torquing forces within the radicular dentin to supportive tissue along their roots. The case studies that follow show how an interdisciplinary approach was used to use complete veneer crowns after custom cast posts to repair severely damaged treated teeth and restore their appearance and functionality. Coordinated prosthetic and endodontic treatments with careful consideration of the patient's expectations and requirements were crucial for a positive result and patient satisfaction. For a very long period, a cast metal post and core were used to provide the foundation restoration for a prosthetic crown. The cast post and core system has the benefit that the core is a natural extension of the post. It is intended for the post to keep the core restoration, which rebuilds the destroyed coronal structure. In this article, cast post and core and porcelain fused to metal restorations for injured maxillary central incisors are discussed.

A Comparative Study of Success Rates of Post and Core Treated Anterior and Posterior Teeth Using Cast Metal Posts.

BACKGROUND: Post and core restorations are performed (generally after treating the root canals of the tooth) when the majority of the tooth structure has been rendered ineffective to support itself/the crown of the tooth. In this clinical study, we aim to compare the difference between post and core treatment of anterior and posterior teeth and their success/failure rates. OBJECTIVE: Our investigation aimed to compare the clinical survival rates of custom-fabricated cast metal post-and-cores in cases of anterior and posterior teeth while controlling for the population's age and gender, type of post material, length of the post, amount of alveolar bone tissue supporting the roots, tooth location in the dental arch, and type of cement used, as well as the effect of opposing dentition and the type of definitive prosthetic treatment received. METHODS: 112 individuals who had received root canal therapy (RCT) and were chosen to receive post and core therapy following their RCT were chosen for the study, and a total of 164 teeth were scheduled to undergo the therapy. All the posts used were made of cast metal, and the patients were divided into two groups: 48 individuals had the posts placed in their posterior teeth (a total of 71 teeth in this case), and the second group was made up of the remaining 64 patients, all with 93 teeth in the anterior region. The follow-up was done twice at a six-month interval after cementation was complete. RESULTS: No significant changes were observed between the stability of the post structures in the anterior and posterior teeth that were examined, and the survival rates were found to be similar in both instances. CONCLUSION: The cast metal posts performed at a similar success rate for the one-year period when the teeth were under our observation, and there were no considerable changes seen statistically. But it must be mentioned that a short follow-up period was observed, so the results might probably see some variations when a longer period of time is taken into consideration.

Post Placement and Restoration of Endodontically Treated Canines: A Finite Element Analysis Study.

The purpose of this study was to show the improved outcomes of restoring endodontically treated teeth with fiberglass posts compared to restorations using metal posts. In our study, we used the Finite Element Method (FEM), which is based on the principle that a physical model that supports a given load distributes the stress throughout its volume. We sought to assess what stress results in a tooth when it is restored using a fiberglass post compared to restoration using a metal post. The finite element analysis showed that a system consisting of a tooth with a fiberglass post is more stable in terms of the maximum stress than a system consisting of a tooth with a metal post. The maximum displacements and deformations were obtained in the case of a canine restored with a fiberglass post, which showed that this system had a high elasticity, therefore, higher strength than a canine restored with a metal post, which had high rigidity.

Posts in Primary Teeth-Past to Present: A Review of Literature.

Early childhood caries is indeed a devastative situation for both patients' parents and pediatric dentists. The primary goal in treating severe early childhood caries is to restore normal function such as maintenance of mesiodistal and vertical dimension, prevention of alteration of mastication, phonetics (due to premature loss), development of parafunctional habits, and prevention of psychological problems affecting the self-esteem of a child. The restoration of primary dentition with extensive carious lesions is a complex clinical challenge of several dimensions. The severity of this condition in maxillary anterior teeth has prompted the extraction of teeth due to inadequate esthetic treatment options. The only concern with the severely destructed primary incisors is a lack of crown structure, which fails to support and adhere to a composite crown. Clinicians have preferred many restorative modalities for esthetic rehabilitation of badly decayed anterior primary teeth with numerous root canal retentive post and core systems with appropriate techniques to preserve those teeth until they are replaced by permanent teeth. This review highlights the various posts, their indications, principles, ideal properties, and the current concepts on their use in pediatric dentistry. HOW TO CITE THIS ARTICLE: Martin AG, Shivashakarappa PG, Arumugam S, et al. Posts in Primary Teeth-Past to Present: A Review of Literature. Int J Clin Pediatr Dent 2021;14(5):705-710.

Fracture resistance of endodontically-treated maxillary premolars restored with different type of posts and direct composite reconstructions: A systematic review and meta-analysis of in vitro studies.

OBJECTIVE: To conduct a systematic review and meta-analysis to assess if the presence of an endodontic post may increase the fracture resistance of endodontically-treated maxillary premolars directly restored with composite. METHODS: A comprehensive systematic literature search according to the PRISMA statement was conducted to assess in vitro studies including endodontically-treated maxillary premolars, restored with different type of posts supporting direct composite reconstructions. Two groups of meta-analyses were performed using fixed effects model and additional Trial Sequential Analysis (TSA) was carried out. Moreover, risk of bias was conducted and quality of evidence for any performed meta-analysis was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS: Twenty-four articles met the inclusion criteria and 13 studies also underwent quantitative evaluation. Fracture resistance of endodontically-treated premolars restored with fiber posts was significantly less than sound teeth (p value: < 0.00001), however endodontically-treated premolars with a fiber post provided an increase in fracture resistance when compared to equivalent teeth restored without post (p value: 0.003). TSA revealed high power of both meta-analyses. Moderate risk of bias was reported in 23/24 studies; only 1 study showed high risk of bias. GRADE system showed moderate strength of evidence due to the presence of a study with high risk of bias and to wide confidence intervals. SIGNIFICANCE: Within the limitation of the present systematic review and meta-analysis, it can be concluded that endodontically-treated maxillary premolars restored with a fiber post and direct composite restoration demonstrated increased fracture resistance when compared to equivalent teeth without post.

Effects of ferrule and diameter of parallel cast post and core on fracture resistance / Efeitos da férula e diâmetro de núcleos metálicos paralelos na resistência a fratura

Objective: The aim of this study was to evaluate the effects of using different diameters of parallel cast posts with, or without ferrule, on the overall fracture resistance of Cast Post and Core (CPC). Material and Methods: Forty (40) endodontically treated human maxillary central incisors were divided into four groups (n=10): [F1] 1.0 mm diameter post with ferrule; [NF1] 1.0 mm diameter cast post without ferrule; [F1.5] 1.5 mm diameter cast post with ferrule; [NF1.5] 1.5 mm diameter post without ferrule. For all teeth, the post space (9.0 mm, in depth) was prepared using ParaPostTM drill. CPC using base metal alloy were fabricated and were cemented using resin modified glass ionomer (RMGI) cement along with the Porcelain Fused to Metal (PFM) crowns. A universal testing machine (Instron) was used to apply horizontal force perpendicular to the long axis of the tooth at the center of lingual surface, until catastrophic failure. Data was submitted to two-way ANOVA and Scheffé tests (P<0.05). Results: Both post diameter and ferrule statistically affected the maximum load at fracture (P=0.004 and P=0.013, respectively). The highest mean values were observed for samples with ferrule and wider post size (490N), while the lowest were observed for samples without ferrule and narrower post size (254N). There was no relationship between the presence of a ferrule and post size (P=0.937). Conclusion: For endodontically treated teeth with no ferrule, a wider-diameter cast post increased fracture resistance of a CPC and PFM crown procedure. (AU)

Objetivo: O objetivo do presente estudo foi avaliar os efeitos de diferentes diâmetros de núcleos metálicos paralelos (com ou sem férula) na resistência a fratura do procedimento restaurador. Material e Métodos: Quarenta (40) incisivos centrais superiores humanos foram tratados endodonticamente e divididos em quarto grupos (n=10): [F1] Diâmetro de 1.0 mm, com férula; [NF1] Diâmetro de 1.0 mm, sem férula; [F1.5] Diâmetro de 1.5 mm, com férula; [NF1.5] Diâmetro de 1.5 mm, sem férula. Para todos os dentes, o espaço foi preparado para o núcleo (9.0 mm, em comprimento) utilizando brocas do ParaPostTM. Os núcleos metálicos e as coroas metalocerâmicas fabricadas foram cimentados utilizando-se cimento de ionômero de vidro modificado por resina. Uma máquina de ensaios universal (Instron) foi utilizada para aplicar uma força horizontal perpendicular ao longo eixo do dente, no centro da face lingual, até falha catastrófica. Os dados foram analisados através de análise de variância de dois fatores e teste de Scheffé (p<0.05). Resultados: O diâmetro do núcleo e a presença (ou ausência) de férula afteram estatiscamente a resistência máxima a fratura do procedimento (P=0.004 e P=0.013, respectivamente). Os maiores valores foram observados para amostras com férula e de maior diâmetro (490N), enquanto os menores valores foram observados para amostras sem férula e de menor diâmetro (254N). Conclusão: Para dentes tratados endodondicamente, com férula, um núcleo de maior diâmetro aumentou a resistência a fratura de procedimentos restauradores envolvendo coroas metalocerâmicas cimentadas sobre núcleos metálicos fundidos. (AU)

Effect of 830 nm Diode Laser Irradiation of Root Canal on Bond Strength of Metal and Fiber Post.

OBJECTIVE AND BACKGROUND: The correct selections of the cementing agent, the endodontic post material and placement protocol are critical to provide an increased longevity of the teeth that went through endodontic treatment. The irradiation with diode laser before post cementation, can promote an antimicrobial effect. However, there is a lack of information about the effect of 830 nm diode laser on the post bond strength. This study analyzed the effect of dentin root canal irradiation with high-intensity diode laser, at 830 nm, operating in continuous or pulsed mode, on the retention of metal or fiber posts, cemented with self-etching resinous composite (Panavia F) and zinc phosphate cement (ZnPO4). MATERIALS AND METHODS: Human roots were irradiated with diode laser (continuous and pulsed mode). The fiber posts were luted with Panavia F and the metal posts with Panavia F or ZnPO4 cement. Specimens were sectioned into three sections (cervical, middle, and apical). The bond strength was measured by a push-out mechanical analysis. For the statistical analysis, a three-way ANOVA test was applied following a Tukey's pairwise comparison with a significance level of p = 0.05. RESULTS: The irradiated groups presented higher bond strength compared with nonirradiated group (p < 0.05), and the cervical and middle thirds presented higher on bond strength than the apical. The association of metal post and Panavia F presented higher bond strength when irradiated on continuous mode (p < 0.05). Fiber post and Panavia F presented higher bond strength associated to pulsed mode. The mode seems not to make a significant difference. CONCLUSIONS: These results corroborate the importance of the post bond to dentin and root canal debris removal to increase the tooth longevity. It was shown that the dentin to post bond strength were enhanced by the diode laser irradiation either on continuous or pulsed modes.

Comparison of resistance to fracture between three types of permanent restorations subjected to shear force: An in vitro study.

INTRODUCTION: Our study's objective was to compare resistance to fracture between endocrown and conventional post and core restorations when subjected to shear force. MATERIALS AND METHODS: Thirty human mandibular premolars were extracted for orthodontic reasons, endodontically treated, and restored using three different methods: endocrown, glass fiber post and composite resin core, and metal post. All the crowns were made from IPS e.max ceramic. Shear forces were applied to these restorations using a test machine until breakage. Load and displacement were recorded every 0.1 s. RESULTS: No significant difference was observed in resistance to fracture between glass fiber post and metal post. No relationship between the displacement of prosthetic dental system and type of material used was uncovered and by comparing the type of fracture with the restoration material used. However, a greater number of favorable fractures were observed in the glass fiber group whereas most of the fractures in the endocrown and metal post groups were unfavorable. CONCLUSION: Endocrown displays better resistance to fracture compared to conventional post and core restorations. In addition, endocrown did not show more displacement or cause more unfavorable fractures than the conventional restorations. This restoration may represent a reliable alternative for restoring a damaged, endodontically treated tooth.

Survival of Composite Resin Restorations of severely Decayed Primary Anterior Teeth retained by Glass Fiber Posts or Reversed-orientated Metal Posts.

AIM: The aim of this study was to compare the survival of composite resin restorations retained by glass fiber posts or reversed-orientated (upside-down) metal posts in severely decayed primary anterior teeth after 6, 12, and 18 months. MATERIALS AND METHODS: A total of forty-four 3- to 5-year-old children with bilateral severely decayed primary maxillary canines were included. Patients were treated under general anesthesia. After pulpectomy, an intracanal post was seated in the primary maxillary canine on each side: either a glass fiber post or a metallic post in reversed orientation and teeth restored with light-cured composite. Survival rate of each technique was evaluated at predetermined follow-ups and data were analyzed with McNemar's test (α = 0.05). RESULTS: The difference in survival of restorations retained by two types of posts was not statistically significant in clinical and radiographical evaluations after 6, 12, and 18 months. The survival rate of reversed-orientated metal and glass fiber posts after 18 months was 81.1 and 67.6% respectively (p = 0.14). CONCLUSION: Reversed-orientated metal post did not show lower clinical survival compared with glass fiber posts in 18-month follow-up. Hence, reversed-orientated metal post can be considered as a potential method to obtain retention for composite restorations in severely decayed primary anterior teeth. How to cite this article: Vafaei A, Ranjkesh B, L0vschall H, Erfanparast L, Jafarabadi MA, Oskouei SG, Isidor F. Survival of Composite Resin Restorations of severely Decayed Primary Anterior Teeth retained by Glass Fiber Posts or Reversed-orientated Metal Posts. Int J Clin Pediatr Dent 2016;9(2):109-113.

Liquid chromatography coupled to different atmospheric pressure ionization sources-quadrupole-time-of-flight mass spectrometry and post-column addition of metal salt solutions as a powerful tool for the metabolic profiling of Fusarium oxysporum.

Fusarium oxysporum L11 is a non-pathogenic soil-borne fungal strain that yielded an extract that showed antifungal activity against phytopathogens. In this study, reversed-phase high-performance liquid chromatography (RP-HPLC) coupled to different atmospheric pressure ionization sources-quadrupole-time-of-flight mass spectrometry (API-QTOF-MS) was applied for the comprehensive profiling of the metabolites from the extract. The employed sources were electrospray (ESI), atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI). Post-column addition of metal solutions of Ca, Cu and Zn(II) was also tested using ESI. A total of 137 compounds were identified or tentatively identified by matching their accurate mass signals, suggested molecular formulae and MS/MS analysis with previously reported data. Some compounds were isolated and identified by NMR. The extract was rich in cyclic peptides like cyclosporins, diketopiperazines and sansalvamides, most of which were new, and are reported here for the first time. The use of post-column addition of metals resulted in a useful strategy for the discrimination of compound classes since specific adducts were observed for the different compound families. This technique also allowed the screening for compounds with metal binding properties. Thus, the applied methodology is a useful choice for the metabolic profiling of extracts and also for the selection of metabolites with potential biological activities related to interactions with metal ions.

Three-dimensional finite element analysis of stress distribution in a tooth restored with metal and fiber posts of varying diameters: An in-vitro study.

OBJECTIVE: To compare stress distribution in a tooth restored with metal and fiber posts of varying diameters (1.2 and 1.4 mm) by means of three-dimensional finite element analysis (3D-FEA). MATERIALS AND METHODS: Four 3D-FEA models were constructed: (1) fiber post (1.2 and 1.4 mm) and (2) metal post (1.2 and 1.4 mm). The material properties were assigned and a force of 100 N was applied at 45° angle to the longitudinal axis of the tooth onto the palatal surface incisal to the cingulum. Analysis was run and stress distribution pattern was studied. RESULTS: Maximum stresses in the radicular tooth structure for fiber post were higher than that for metal post. In the former models, stresses in the tooth structure were slightly reduced with increase in fiber post diameter. CONCLUSIONS: To reduce stress in the remaining radicular tooth structure, it is better to use a fiber post of a large diameter.

A clinical comparative study on fiber post-retained and metal post-retained restorations of 176 cases / 重庆医学

Objective To compare the clinical effects of fiber post‐retained and metal post‐retained restorations .Methods Two hundred teeth after root canal therapy from 176 patients were divided into 2 groups randomly and each group consisted of 100 teeth .In the experimental group ,teeth were restored with fiber post‐resin core and porcelain crown ,where cast metal‐core and porcelain crown were used in the control group .The teeth were clinically examined regularly for 2 years .The data were analyzed with Chi‐square method .Results At the end of the 2‐year follow‐up ,6 fiber posts dislocated and 2 teeth showed gingival inflammation in the experimental group ,with a clinical success rate of 92% ,the loss rate of 6% .5 gingival inflammation cases ,2 periapical inflammation cases and 7 cases of root fracture occurred in the metal post group ,and the clinical success rate was 85% ,root discount rate of 7% .There was statistical significance between the two groups (P< 0 .05) .Conclusion The loss rate ogf fiber post‐retained restoration is higher than the metal post‐retained restorations ,but the root discount rate is low ,incidence of periodontal and periapical tissue similar in the two groups can be routinely used clinically instead of metal post‐retained restoration .

EFFECTS OF FIBER POST AND CASTING METAL POST IN THE RESTORATION OF LARGE AREA TOOTH DEFECT / 现代医院

Objective To evaluate the effect of repair and chewing function recovery of fiber post and casting metal post in the restoration of large area tooth defect .Methods 100 cases of patients with large area tooth defect from August 2011 to June 2013 in our hospital were chosen to research , and were divided into the control group and the experimental group.The control group were treated with casting metal post , and the experimental group were trea -ted with fiber post.The effect of repair, bite force, chewing function and inflammatory factor levels in gingival crevic -ular between two group were compared .Results Chewing efficiency and bite force of experimental group were higher than the control group, and the difference had significant significance (p <0.05).Off, loose, discoloration and frac-ture repair effect decline rate of experimental were lower than the control group , and IL -6 and IL -8 of the experi-mental group were lower than the control group .The difference were significant(p <0.05).Conclusion Fiber post could effectively improve treatment effects in the restoration of large area tooth defect , chewing functions, and the effect of repair could be greatly improved .

The effects of commonly used dental cast metal posts and cores on MRI / 实用口腔医学杂志

Objective:To observe the influence of commonly used dental cast metal posts and cores on magnetic resonance imaging (MRI)for head and neck.Methods:Six kinds of posts and cores made of metal alloy (Ni-Cr alloy,Co-Cr alloy,titanium alloy,pure titanium,Pd-Au alloy and Au-Pt alloy)were respectively fixed on the mucosa of left palate of a volunteer.The maxillofacial region of the subjects was scanned by routine head sequences SE-T1WI and TSE-T2WI respectively.Results:ANOVA of factorial design analy-sis indicated significant differences of artifacts among metal materials(F=153.63,PCo-Cr alloy>Ni-Cr alloy>Au-Pt alloy>titanium alloy>pure titanium;two posts and cores>one post and core;SE-T1WI>TSE-T2WI.Conclusion:Different cast metal posts and cores have different influences on MRI artifact.Reasonably choosing the metal materials and scanning sequences can minimize artifacts on MRI.

The influence of ultrasound on removal of prefabricated metal post cemented with different resin cements.

BACKGROUND: Ultrasonic vibrations are used to remove a cemented post from a root canal requiring endodontic retreatment. Various results have been reported from the studies that evaluated the effect of ultrasonic instruments in removing the posts cemented with resin cements. The aim of this study was to evaluate the effect of ultrasonic energy on the retention of prefabricated metal post cemented with Panavia or Maxcem Elite cements. MATERIALS AND METHODS: In this in vitro study, forty eight extracted single root premolars were decoronated with a diamond disc leaving a 13 mm long root and endodontically treated. The root canals were obturated by gutta-percha up to 5 mm with vertical condensation method and the 8 mm post-space was prepared to receive a no. 2 long Dentorama post. The roots were placed in an incubator for 48 h in 37°C and 100% humidity. After mounting the teeth in acrylic blocks, posts were cemented in the root canals using Panavia F2.0 in 24 specimens and Maxcem Elite in 24 others. For half of the specimens in each subgroup, an ultrasonic device was applied for 4 min. Universal testing machine was used to measure the force needed to remove the posts with a crosshead speed of 1 mm/min until the post came out of the canal. Kruskal-Wallis test was used for statistical analysis at 5% level of significance. RESULTS: The removal force was not significantly different among the groups (P > 0.05). CONCLUSION: Ultrasonic energy did not decrease the retention of posts cemented with Panavia or Maxcem Elite cements. Furthermore, it seems that there is no significant difference between removal force of self-etch (Panavia) and the self-etch self-adhesive (Maxcem Elite) resin cements.

Glass fiber post versus metal post in the restoration of endodontically treated teeth / 中国组织工程研究

BACKGROUND:The post and core system for residual roots and crowns can achieve satisfactory effects, when fil ing restoration, ful crowns or inlay has poor effects. OBJECTIVE:To evaluate the clinical use of glass fiber post and metal post in the restoration of endodontical y treated teeth. METHODS:A total of 106 patients with 160 endodontical y treated teeth were selected and restored with glass fiber post (n=80 teeth) and metal post (n=80 teeth) fol owed by porcelain-fused-mental crown. The restorations were evaluated clinical y for 9 to 33 months. RESULTS AND CONCLUSION:Glass fiber post treatment for 78 teeth was effective and that for two teeth were failed, with a successful rate of 98%. Metal post restoration was effective in 71 teeth and failed in nine teeth including one tooth of crown fracture, four of root fracture and four of post loss, with a successful rate of 89%. There was statistical y significant difference between two groups (P<0.05). Glass fiber post is better in convenient handling and good color and reduced probability leading to root broken for dental restoration compared with metal post.

Observation for clinical effects of glassfiber post with all-ceramic-crown for incisors restoration / 中国实用护理杂志

Objective To investigate the clinical effect of glassfiber post with all-ceramic-crown for incisors restoration, providing some references for our clinical application. Methods 82 patients (100 teeth defect) in our department from October,2008 to October, 2009 were divided into group A and group B with 50 incisors in each. Glassfiber post with all - ceramic - crown was used in group A, and metal post with porcelain-fused-to-metal in group B. After one year follow-up, we observed the clinical effect. Results 49 cases were effective and 1 case failed in group A. 42 cases were effective and 8 cases failed in group B.There was statistically significant difference between the two groups. Conclusions Glassfiber post with all-ceramic-crown is better in convenient handling and good colour for incisors compared to metal post with porcelain-fused-to-metal.

A in vitro study of coronal microleakage of different post and cement systems / 实用口腔医学杂志

Objective: To compare the coronal sealing abilities of different post and cement systems through measuring the value of leakage by using dye method. Methods: Fifty human mandibular premolars with single canal were divided into 6 groups randomly. A group: roots sealed by temporary material, B group: roots restored with fiber post adhered with composite resin cement, C group: roots restored with casting metal post and core adhered with composite resin and zinc phosphate cement, D group: positive control, E group: negative control. After finishing preparation and restoration of roots, microleakage was determined by using dye method. Results: The groups restored with any post and core system produced significantly less microleakage than temporary material sealing group(P<0.05). But no differences were detected between two groups bonded with the composite resin cement (P>0.05). Posts adhered with zinc phosphate luting agent produced more leakage than those with composite resin cement(P<0.05). Conclusion: Luting agent can decrease the coronal microleakage. Composite resin cement provides better sealing ability.