Effect of the Crown Preparation Margin and Die Type on the Marginal Accuracy of Fiber-reinforced Composite Crowns

2008 ◽  
Vol 9 (2) ◽  
pp. 9-16 ◽  
Author(s):  
Mohamed F. Ayad
Keyword(s):  
Epoxy Resin ◽  
Finish Line ◽  
Fiber Reinforced Composite ◽  
Reinforced Composite ◽  
Measuring Microscope ◽  
Significant Difference ◽  
Die Material ◽  
Tooth Preparation ◽  
The Difference ◽  
Crown Preparation

Abstract Aim The objective of this laboratory investigation was to determine the effect of different preparation designs (light chamfer, deep chamfer, and shoulder) and die-making materials (stone and epoxy) on the resulting margin misfit for fiber-reinforced composite crowns using a measuring microscope. Methods and Materials Sixty standardized FibreKor crowns were made on stone and epoxy resin dies (n=30 each) duplicated from three metal master dies representing complete crown tooth preparation with a total convergence of 5°. For each die group, three of the tooth preparation designs were established in relation to the type of finish line (n=0 each) as follows: Group A (0.5-mm light chamfer finish line); Group B (1.0-mm deep chamfer finish line); and Group C (1.0-mm shoulder finish line). Marginal accuracy was evaluated by measuring the distances between each of four pairs of indentations on the crowns and on the dies with a Nikon measuring microscope. Results Analysis of seating measurements with parametric analysis of variance and Tukey's Studentized Range (HSD) disclosed a statistically significant difference for both tooth preparation design and die material (p< 0.001). However, the interaction effect was not significant (p=0.9073). The least marginal opening value was for FibreKor crowns made on epoxy resin dies with a light chamfer finish line (57 μm), but the difference was not statistically significantly different from crowns made on epoxy resin dies with a deep chamfer light chamfer finish line (61 μm). However, crowns made on epoxy resin dies with a shoulder finish line (81 μm) had significantly higher values (p< 0.05). FibreKor crowns made on stone dies with the shoulder finish line (95 μm) had statistically higher marginal opening values (p< 0.05). The least marginal opening value was for crowns made on stone dies with a light chamfer finish line (66 μm), but the difference was not statistically significantly different from crowns made on stone dies with a deep chamfer light chamfer finish line (70 μm). Conclusions Significant differences were found among the die material used for the shoulder margin design. However, there was no significant difference between light chamfer and deep chamfer margin designs for both die materials. Citation Ayad MF. Effect of the Crown Preparation Margin and Die Type on the Marginal Accuracy of Fiberreinforced Composite Crowns. J Contemp Dent Pract 2008 February;(9)2:009-016.

Mechanical loss in a glass-epoxy composite

1990 ◽  
Vol 5 (5) ◽  
pp. 913-915 ◽  
Author(s):  
Manfred Weller ◽  
Hassel Ledbetter
Keyword(s):  
Epoxy Resin ◽  
Epoxy Composite ◽  
Glass Fibers ◽  
Resin Matrix ◽  
Torsion Pendulum ◽  
Loss Peak ◽  
Mechanical Loss ◽  
Fiber Reinforced Composite ◽  
Reinforced Composite ◽  
Computer Controlled

Using a computer-controlled inverted torsion pendulum at frequencies near 1 Hz, we determined the mechanical losses in a uniaxially fiber-reinforced composite. The composite comprised glass fibers in an epoxy-resin matrix. We studied three fiber contents: 0,41, and 49 vol.%. Three mechanical-loss peaks appeared: above 300 K, near 200 K, and near 130 K. They correspond closely to α, β, and γ peaks found previously in many polymers. We failed to see a mechanical-loss peak for either the glass or the glass-resin interface. Between 300 and 4 K, the torsion modulus increased in the resin by a factor of 3.30 and in the 0.49 glass-epoxy by a factor of 2.37.

scholarly journals Clinical evaluation of fiber-reinforced composite crowns in pulp-treated primary molars: 12-month results

2016 ◽  
Vol 10 (04) ◽  
pp. 522-528 ◽  
Author(s):  
Zahra Mohammadzadeh ◽  
Iman Parisay ◽  
Maryam Mehrabkhani ◽  
Azam Sadat Madani ◽  
Fatemeh Mazhari
Keyword(s):  
Retention Rate ◽  
United States Public Health ◽  
Retention Rates ◽  
Fiber Reinforced ◽  
Secondary Caries ◽  
Fiber Reinforced Composite ◽  
Marginal Integrity ◽  
Reinforced Composite ◽  
Gingival Health ◽  
Significant Difference

ABSTRACT Objective: The aim of this study was to evaluate the clinical performance of tooth-colored fiber-reinforced composite (FRC) crowns in pulp-treated second primary mandibular teeth. Materials and Methods: This split-mouth randomized, clinical trial performed on 67 children between 3 and 6 years with two primary mandibular second molars requiring pulp treatment. After pulp therapy, the teeth were randomly assigned to stainless steel crown (SSC) or FRC crown groups. Modified United States Public Health Service criteria were used to evaluate marginal integrity, marginal discoloration, and secondary caries in FRC crowns at intervals of 3, 6, and 12 months. Retention rate and gingival health were also compared between the two groups. The data were analyzed using Friedman, Cochran, and McNemar's tests at a significance level of 0.05. Results: Intact marginal integrity in FRC crowns at 3, 6, and 12 months were 93.2%, 94.8%, and 94.2%, respectively. Marginal discoloration and secondary caries were not found at any of the FRC crowns. The retention rates of the FRC crowns were 100%, 98.3%, and 89.7% at 3, 6 and 12 months, respectively, whereas all the SSCs were found to be present and intact after 12 months (P = 0.016). There was no statistically significant difference between the two groups in gingival health. Conclusion: According to the results of this study, it seems that when esthetics is a concern, in cooperative patients with good oral hygiene, FRC crowns can be considered as a valuable procedure.

scholarly journals A vivo study on dowel crown with more aesthetic and healthy Fiber Reinforced Composite post system

2012 ◽  
Vol 9 (1) ◽  
pp. 15-18
Author(s):  
Hasibul Hasan ◽  
Kasi Hasinur Rahman ◽  
Shamim Sultana ◽  
Md Mahfuzur Rahman ◽  
Md Shasul Alam
Keyword(s):  
Statistical Significance ◽  
Core Material ◽  
Fiber Reinforced ◽  
Core System ◽  
Promising Alternative ◽  
Fiber Reinforced Composite ◽  
Reinforced Composite ◽  
Significant Difference ◽  
Group B ◽  
Carious Teeth

Statement of problem. Patients having grossly carious teeth with broken down crown are needed to be restored with post & core after endodontic treatment. Root canal posts are widely used & come in a variety of metals & forms. However, cast metal posts, although better than other post & core systems, still possess some disadvantages, like corrosion & discoloration at the gingival margin of the treated tooth & cause aesthetic problem. These problems are overcome with the recently introduced post & core material. The fiber reinforced composite post & core material is a superior & efficient alternative to cast post. Purpose. The purpose of this study was to investigate the success of fiber reinforced composite post & core system over conventional metallic system in regards of corrosion & discoloration resistance with periodontal condition on post treated tooth. Materials & Methods. This was a prospective study, conducted in the department of Conservative Dentistry & Endodontics, B.S.M.M.U. 40 patients were purposively selected who attended in this department with grossly carious teeth with badly broken crown without apical infection as the subject of this study & divided in two groups. 20 patients were included in group A as case subjects & they were treated with fiber reinforced post & core system. 20 patients were included in group B as control subjects. They were treated with conventional cast metallic post & core system. After twelve months, recorded data were compiled on a master chart and statistically analyzed. Chisquare test and t-test (unpaired) were done for statistical significance (P<0.05). Results. Very highly significant difference (p<.001) was observed between the groups in the evaluation of resistance to corrosion & discoloration, there were no significant difference (p>.05) in periodontal evaluation Conclusion. This study revealed that fiber reinforced composite post & core system can overcome the problems faced by the metallic post & core system. So it can be concluded that fiber reinforced composite post & core system can be a promising alternative in comparison to metallic post & core system.DOI: http://dx.doi.org/10.3329/cdcj.v9i1.11832 City Dental College Journal Vol.9(1) 2012 15-18

scholarly journals Composite Resin Core Buildups With and Without Post for the Restoration of Endodontically Treated Molars Without Ferrule

2016 ◽  
Vol 41 (1) ◽  
pp. 64-75 ◽  
Author(s):  
P Magne ◽  
J Goldberg ◽  
D Edelhoff ◽  
J-F Güth
Keyword(s):  
Glass Ceramic ◽  
Composite Resin ◽  
Published Data ◽  
Fiber Reinforced ◽  
Fiber Reinforced Composite ◽  
Reinforced Composite ◽  
Resin Core ◽  
Significant Difference ◽  
Ceramic Crowns ◽  
Dual Curing

SUMMARY Objective The aim of this study was to investigate the restoration of highly damaged, broken-down endodontically treated molars without the ferrule effect using glass ceramic crowns on different dual-cure composite resin core buildups. Methods and Materials Thirty (N=30, n=15) decoronated, endodontically treated teeth (no ferrule) were restored without a ferrule with a direct buildup using the dual-curing composite Multicore HB (group MHB) or the dual-curing composite core buildup Multicore Flow in combination with glass-fiber–reinforced composite post (FRC post; group MFP). All teeth were prepared to receive bonded glass ceramic crowns (Empress CAD luted with Variolink II) and were subjected to accelerated fatigue testing. Cyclic isometric loading was applied to the palatal cusp at an angle of 30 degrees and a frequency of 5 Hz, beginning with a load of 200 N (×5000 cycles), followed by stages of 400, 600, 800, 1000, 1200, and 1400 N at a maximum of 30,000 cycles each. Specimens were loaded until failure or to a maximum of 185,000 cycles. Groups were compared using the life table survival analysis (log rank test at p=0.05). Average fracture loads and number of survived cycles were compared with one-way analysis of variance (Scheffé post hoc at p=0.05). Previously published data from the same authors about core buildups made of high-performance polymers (group HPP, n=15) and light-curing composite resin without FRC posts (group TEC, n=15) and with FRC posts (group TECP, n=15) using the same experimental setup were included for comparison. Results None of the tested specimen withstood all 185,000 load cycles. There was no significant difference in mean fracture load (p=0.376), survived cycles (p=0.422), and survival (p=0.613) between MHB (facture load 859.4 N±194.92) and MFP (796.13 N±156.34). Group HPP from a previous study appeared to have significantly higher performance than all other groups except MHB. All groups with posts were affected by an initial failure phenomenon (wide gap at the margin between the buildup/crown assembly and the root). Conclusions HPP and MHB enhanced the performance of all-ceramic leucite-reinforced glass ceramic crowns, and insertion of a fiber-reinforced composite post was not influential when using other materials.

scholarly journals Ex Vivo Assessment of Natural Teeth Wear against Zirconia and Novel Glass-Fiber-Reinforced Composite Crowns in Primary Teeth by a Three-Dimensional Assessment Method

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Abhinav Talekar ◽  
Gayatri Chaudhari ◽  
Sreekanth Kumar Mallineni ◽  
Sneha Kothare ◽  
Amol Patil ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Glass Fiber ◽  
Primary Teeth ◽  
Fiber Reinforced ◽  
Fiber Reinforced Composite ◽  
Reinforced Composite ◽  
Glass Fiber Reinforced ◽  
Study Results ◽  
Significant Difference ◽  
Natural Teeth

Objectives. The main purpose of the study was to assess the material wear, antagonistic natural primary teeth wear, and microhardness of zirconia (ZR), a recently launched novel glass-fiber-reinforced composite crown (GFRC). The research question was, are these aesthetic crowns resulting in antagonistic natural primary tooth wear and the crown material itself? Methods. Forty-five primary canines were divided into three groups (15 per group) and mounted against Zr (Group A), GFRC (Group B), and natural teeth as control (Group C) in the wear test machine. All samples were assessed for surface wear with pre- and post-3-dimensional scanning. In addition, microhardness was assessed for all three groups. Results. The mean microhardness value for the Zr disc was 1157 ± 7 HV; for the GFRC disc, it was 29.35 ± 2 HV; while with natural teeth, it was 105 ± 4 HV. There was a statistically significant difference in teeth wear in the prescan and postscan in the natural tooth ( p < 0.05 ) group, highly significant difference ( p < 0.001 ) in the ZR group, and no significant difference in the GFRC group. Conclusion. There is more significant wear loss of glass-fiber-reinforced composite discs as compared to zirconia. In addition, the wear of the antagonistic tooth with zirconia and natural teeth is more remarkable than with GFRC. There is a vast difference of microhardness between natural teeth and zirconia (almost 10 times higher) which suggests further scope of study. Clinical Relevance. Pediatric dentistry deals with the transition of dentition from primary to permanent through mixed dentition. Selection of restorative material needs to be done cautiously when we are dealing with primary teeth and young permanent teeth as antagonistic teeth. Wear of the crown material itself and opposing natural teeth are essential factors that should be considered in selecting crowns in clinical practice. The present study results can be extrapolated to clinical practice, and the practitioner can consider various factors in selecting full-coverage crowns for primary teeth. The vast difference in aesthetic crowns and natural teeth microhardness indicates a further need for research. Additionally, there is no literature published for the recently launched GFRCs.

scholarly journals Different Types of Finish Lines, Gingival Retraction Methods and Impression Techniques Used During Single Crown Preparation

2020 ◽  
Vol 11 (SPL3) ◽  
pp. 1192-1201
Author(s):  
Ahmed Hilal Sheriff K ◽  
Nivedhitha M S ◽  
Rakshagan V
Keyword(s):  
Statistical Significance ◽  
Daily Routine ◽  
Chi Square ◽  
Finish Line ◽  
Impression Technique ◽  
Single Crown ◽  
Chi Square Test ◽  
Tooth Preparation ◽  
Crown Preparation ◽  
University Setting

Tooth preparation is part of the daily routine for dentists. Each step involved in the tooth preparation is important. This study focuses on three parameters, finish lines, retraction methods and impression technique. retraction and impression technique go hand in hand, as retraction of the is mandatory to expose the prepared finish line and record them accurately. This study aimed to determine various types of finish lines, retraction methods and impression techniques incorporated during single crown preparation in Saveetha Dental College and Hospitals. Case records were collected from DIAS (Dental Information Archiving Software). This university setting study involved a sample size of 812 patients. Data was tabulated with parameters of name, age, sex, finish line, retraction, no. of cords, type of impression. The retraction method used was a mechanical retraction method which comprised 794 teeth and 554 of the retraction was done using &quot;2 cords (000+1)&quot;. 2 stage putty wash technique was commonly employed during impression taking in tooth preparation of 746 teeth. Chi-square test done for association between tooth and finish lines, retraction methods, no. of cords used and impression technique did not show any statistical significance (p&gt;0.05) while association of finish line with no. of cords and type of impression showed statistical significance (p&lt;0.05). Within the limit of the study, the most widely used finish line was shoulder finish line and mechanical retraction methods were commonly employed with 2 stage putty wash technique being the most common impression technique.

scholarly journals Does Multi-Fiber-Reinforced Composite-Post Influence the Filling Ability and the Bond Strength in Root Canal?

2021 ◽  
Vol 8 (12) ◽  
pp. 195
Author(s):  
Naji Kharouf ◽  
Salvatore Sauro ◽  
Hamdi Jmal ◽  
Ammar Eid ◽  
Mohamed Karrout ◽  
...  
Keyword(s):  
Bond Strength ◽  
Root Canal ◽  
Testing Machine ◽  
Single Fiber ◽  
Fiber Reinforced ◽  
Fiber Reinforced Composite ◽  
Reinforced Composite ◽  
Filling Ability ◽  
Significant Difference ◽  
Push Out

The purpose of the present in vitro study was to investigate the bond strength of root canal dentin and the filling ability of a new multi-fiber-reinforced composite post (mFRC) compared to a conventional single fiber-reinforced-composite post (sFRC). Twenty-eight freshly maxillary first permanent single-rooted premolars were instrumented and divided into groups (n = 14). Group 1: single-fiber-reinforced composite (sFRC), group 2: multi-fiber-reinforced composite (mFRC). Bonding procedures were performed using a dual-cure universal adhesive system and resin cement. All specimens were sectioned so that seven discs of 1 mm of thickness were obtained from each root. An optical microscope was used before the push-out test to measure the total area of the voids and to determine the length of the smaller/bigger circumferences. The push-out bond strength (PBS) test was performed using an Instron universal testing machine. Data were then compared by one-way ANOVA on ranks (α = 0.05). The dentin–cement–post interface was observed using scanning electron microscopy (SEM). At the coronal third, a significantly higher bond strength (p < 0.05) was obtained in the sFRC group (44.7 ± 13.1 MPa) compared to the mFRC group (37.2 ± 9.2 MPa). No significant difference was detected between the groups at the middle third (sFRC group “33.7 ± 12.5 MPa” and mFRC group “32.6 ± 12.4 MPa”) (p > 0.05). Voids were significantly lower in the mFRC compared to those observed in the sFRC group (p < 0.05) at the coronal third. Whereas, no significant difference was found at the middle third (p > 0.05) between the tested groups. Filling ability was overall improved when employing mFRC, although such technique might have characteristic limitations concerning the bond strength to dentin.

scholarly journals Comparison of marginal adaptation of fiber reinforced composite and metal ceramic full veneer crown

2015 ◽  
Vol 5 (1) ◽  
pp. 1-5
Author(s):  
Tareq Hassan ◽  
Sohana Ferdous ◽  
Aslam Md Aurangjeb
Keyword(s):  
Marginal Adaptation ◽  
Fiber Reinforced ◽  
Female Ratio ◽  
Fiber Reinforced Composite ◽  
Reinforced Composite ◽  
Number Of Patients ◽  
Metal Ceramic ◽  
Group A ◽  
The Difference ◽  
Group B

Fiber reinforcement was introduced to clinical dentistry for the first time in the 1960s when investigators attempted to reinforce polymethyl-methacrylate dentures with glass or carbon fibers. It has recently been shown that crowns, bridges and posts made of FRC can be used successfully in dental practice and on the basis of marginal adaptation they are more acceptable than conventional metal ceramic crown. A prospective comparative cross-sectional study was performed involving 60 patients who attended in the out patients department of Prosthodontics, Faculty of Dentistry, BSMMU during the period of January 2007 to December 2008. Clinical data were recorded for the selected 60 patients who were divided into two groups “experimental” and “control”. Marginal adaptation was indexed after California Dental Associations quality evaluation system. The age of the patients ranged from 18 to 42 years in group A and 17 to 38 years in group B. The highest number of patients was in the age group 21-30 years in both the groups. The mean age was 24.9±5.8 years and 25.0±4.8 years in group A and group B respectively. There were 26 male and 34 female patients in the study and male female ratio was 1:1.3. In group A patients, 12(40.0%) were male and 18(60.0%) female. In group B patients 14(46.7%) were male and 16(53.3%) were female. After 4 months all the patients were in grade I in both the groups. After 8 months all the patients were in grade I in group A and 27(90.0%) patients in grade I in group B.  After 12 months all the patients were in grade I in group A and 25(83.3%) patients were in grade I in group B. The difference was not statistically significant (p>0.05) after 8 months, however after 12 months the difference was significant (p<0.05). The Fiber Reinforced Composite crown represents a valuable development in the field of Prosthetic Dentistry. DOI: http://dx.doi.org/10.3329/bjdre.v5i1.22450 Bangladesh Journal of Dental Research and Education Vol.5(1) 2015: 01-05

Sign in / Sign up

Export Citation Format

Share Document