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Article
Influence of Preparation Design and Presence of Class IV Composite Resin Restoration on Fracture Resistance of Ceramic laminate Veneer

Authors: Abdulfatah Altabal --- Hala Ragab --- Essam Osman
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2015 Volume: 12 Issue: 4 Pages: 1198 -1208
Publisher: Babylon University جامعة بابل

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Abstract

The objective of the study was to evaluate the fracture resistance of ceramic veneer bonded to class IV composite resin restoration using two differentincisal preparation designs.Twenty-eight extracted intact human maxillary incisors free from cracks and of equal dimensions were randomly divided into two main groups; G1 (control): intact teeth without class IV composite restoration, G2: teeth with class IV composite restorations. Each group was further divided according to the preparation design of the laminate veneers (n=7); A: incisal butt joint design and B: incisal overlap design. Class IV was prepared with obliqueincisal margin.Etching and bonding were performed and a nanohybrid composite resin was applied. Two veneer preparation designs were made; butt joint with shoulder finish line and incisal overlap with palatal chamfer. The impression were made usinga 3D-scanner. The veneers were fabricated with a heat pressed all ceramic material (IPS-Emax, IvoclarVivadent) according to manufacturer’s protocol.The internalveneer surface was etched with 5% hydrofluoric acid then silanated.Dual cure resin cement (Variolink N base and catalyst, IvoclarVivadent) wasused for cementation.Fracture resistance measurement was recorded using universal testing machine.The veneer incisal preparation design had a statistically significant effect on mean fracture resistance of PLVs whereas presence of class IV restoration had no statistically significant effect on mean fracture resistance.The incisal overlap design showed statistically significantly higher mean fracture resistance than the incisal butt joint design. The preparation design affected the fracture resistance of PLVs bonded to class IV composite restorations. Yet,the presence of class IV composite restorations did not affectthe fracture resistance of bonded PLVs. The incisal overlap design seemed to protect PLVs bonded to class IV restorations.


Article
Fracture resistance of premolars with bonded amalgam restorations

Authors: Abdul–Haq A Suleiman --- Mohammad Gh Hamdoon
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2003 Volume: 3 Issue: 2 Pages: 156-160
Publisher: Mosul University جامعة الموصل

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Abstract

The aim of this in vitro study is to evaluate the fracture resistance of premolars with three surface amalgam restorations. Fifty premolars were used, and divided into five groups. The teeth in group one remains intact whereas the teeth in the second group prepared and not restored. The teeth in the third group prepared and restored with amalgam only. In groups four and five, the amalgam restorations were lined with All–Bond 2 and Scotchbond Multi Purpose Plus respectively. After thermocycling, the teeth were tested under universal compression machine at a crosshead speed 5 mm/minute. Data were analyzed using one way Analysis of Variance and Duncan’s Multiple Range Test. The results of this study indicates that both Scotchbond Multi Purpose Plus and All–Bond 2 increase the fracture resistance as compared to the control groups (groups two and three). The results of this study also show no significant difference between the two bonding agents regarding teeth fracture resistance.


Article
Influence of post materials on the fracture resistance of endodontically treated teeth.

Author: Dr. Biland M. S. Shukri, BDS. M.Sc.* د.بلند محمد سليم
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2012 Volume: 9 Issue: 1 Pages: 1-9
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The bending stiffness of the post should have the ability to transfer and distributeforces and stresses in an endodontically treated tooth to prevent root fracture. The aimof this study was to evaluative the post materials on the fracture resistance ofendodontically treated teeth restored with three types of post materials. Thirtyextracted human mandibular premolars after root canal preparation and obturationwith gutta percha; the roots were divided into three groups according to the type ofpost material, group Fc restored with fiber post, group Sc restored with stainless steelpost and group Tc restored with titanium post. All teeth restored with compositerestorative material as core materials. Then all the teeth were subjected tocompressive load at 130o angle from the horizontal plan at a 5mm/min crossheadspeed until fracture. Results showed that there was a significant different betweengroups in term of fracture loads (P= 0.0301). Also the fracture loads of teeth restoredwith titanium post has highest mean fracture load (830N), whereas teeth restored withFiber post demonstrated the lowest mean fracture load (701.3N). This studyconcluded that the teeth restored with metallic post were more fracture resistant thanthose restored with fiber posts. But the combination of a fiber post and composite corehas the favorable mode of fracture that considered reparable, while consideredunfavorable when restored with metallic post.


Article
Effect of different partial ferrule locations on the fracture resistance of endodontically treated teeth restored with fiber posts and complete crowns

Author: Haider Hasan Jasim.
Journal: Tikrit Journal for Dental Sciences مجلة تكريت لعلوم طب الاسنان ISSN: 20731213 Year: 2016 Volume: 4 Issue: 1 Pages: 39-49
Publisher: Tikrit University جامعة تكريت

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Abstract

Purpose. The purpose of this in vitro study was to evaluate the effect of partial ferrule locations on the fracture resistance of endodontically treated maxillary canines restored with complete crowns. Material and Methods. Fifty extracted maxillary canines were sectioned 18 mm from their apices, endodontically treated, and divided into 5 groups of 10 teeth each. All groups were prepared with full shoulder crown preparations. the first group having axial wall heights of 2 mm around the preparation circumferences, the axial walls were circumferential, 360 degrees around the preparations (Complete group), the second, third, and forth groups the axial walls were continuous for 180 degrees (one half of the axial tooth structure) of Palatal, Labial, and Proximal groups, and the fifth group all axial tooth structure was sectioned to the level of the preparation shoulder (Level group). All prepared teeth were then restored with quartz fiber posts (RTD), composite resin (Multicore) cores, and complete metal crowns. The fracture resistance was measured in a universal testing machine at 135 degrees to the long axis of the tooth until failure. Data were analyzed by ANOVA and then by Least Significance Difference test (LSD). The mode of failure was determined by visual inspection of all specimens. Results. Significant differences (P<0.05) were found among the mean fracture loads of the test groups, and was 803.7 N, 747.7N, 347.3 N, 386.6 N, and 186.7N for the Complete, Palatal, Labial, Proximal, and Level groups, respectively. When the mode of failure was evaluated, all failure was an oblique palatal to facial root fracture for the groups with remaining coronal tooth structure. In the Level group, post debonding was the predominant mode of failure. Conclusion. The palatal axial wall was more effective than the labial or proximal axial wall in providing fracture resistance to force applied to the palatal aspect in endodontically treated teeth.


Article
Fracture Resistance of Endodontically Treated Premolar Teeth with Extensive MOD Cavities Restored with Different Bulk Fill Composite Restorations (An In vitro Study)

Authors: Bilal H. Ibrahim --- Haitham J. Al-Azzawi
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2017 Volume: 29 Issue: 2 Pages: 26-32
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The present in-vitro study was undertaken to evaluate and compare fracture resistance of weakenedendodontically treated premolars with class II MOD cavities restored with different bulk fill composite restorations (EverXposterior, Alert, Tetric EvoCeram Bulk Fill, and SDR). The type and mode of fracture were also assessed for all theexperimental groups.Materials and Method: Forty-eight human adult maxillary premolar teeth were selected for this study. Standardizedextensive class II MOD cavities with endodontic treatment were prepared for all teeth, except those that were saved asintact control. The teeth were divided into six groups of eight teeth each (n=8): (Group 1) intact control group, (Group 2)unrestored teeth with endodontic treatment, (Group 3) restored with (TetricEvoCeram Bulk Fill), (Group 4) restored withSDR bulk-fill flowable composite, (Group 5) restored with EverX Posterior composite and (Group 6) restored with Alertcomposite. . All specimens were subjected to compressive axial loading until fracture in a universal testing machine. Thedata were statistically analyzed using one-way ANOVA test and LSD test. Macroscopic fracture type were observed andclassified into favorable and unfavorable. Specimens in groups 3, 4, 5 and 6 were examined by stereomicroscope at amagnification of 20× to evaluate the mode of failure into adhesive, cohesive or mixed.Results: The mean fracture load was (1.2505Kn) for group 1, (0.371Kn) for group 2, (0.512 Kn) for group 3, (0.6435 Kn) forgroup 4, (0.608 Kn) for group 5, and (0.8315) for group 6. Using one way ANOVA test a highly significant difference (P <0.01) were found among all groups. The use of Alert composite (which contain micro glass fiber) improved the fractureresistance significantly in comparison to other groups. SDR bulk-fill flowable composite showed better improvement infracture resistance but with no significant differences in comparison to EverX composite restoration (which contain ShortE-glass fiber filler). The type of failure was unfavorable for all the restored groups.Conclusion: All experimental composite restorations showed significant improvement in the resistance to cuspal fracturein comparison to unrestored one (group 2). However, under the conditions of this study, direct composite restorationsshould be considered as a valid interim restoration for weakened endodontically treated teeth before cuspal coveragecan be provided


Article
Assessment of the fracture strength of straight and pre-angled (17°) zircon implant abutments supported CADCAM zerconium restoration: An in(vitro study).

Authors: Zardasht N. Abdulghafoor --- Talal H. Al-salman --- Allaa Y. Daham
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2016 Volume: 16 Issue: 28 Pages: 77-83
Publisher: Mosul University جامعة الموصل

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Abstract

Aims :evaluate the effect of abutment angulation on fracture strength of pre-fabricated zircon implant abutment supported CADCAM zircon crown. Material and methods: Ten analog with 3.75×14mm were placed into resin blocks divided in to 2 groups: group A (n=5) parallel to long axis and group B (n= 5) fixed at angulation (17°) to long axis. Then ten abutments were tightened to 25 N/cm2. Ten full anatomic zircon (CAD/CAM) crowns constructed as upper right central incisor: 5 on each group. After luting all crowns with dual cure resin-based luting, all samples passed to artificial aging using thermocycling machine, 500 cycles at (5 to 55 C°±2) degree. Then the load was applied by universal testing machine at 30 degree to the long axis until fracture occurred. Results: Statistical analysis showed that the implant abutment angulations significantly (p < 0.05) reduced the fracture resistance of zircon implant abutment. Conclusions: Within the limitation of this in vitro study it may be concluded that: the fracture strength of zircon implant abutment supported CADCAM zircon crown is significantly reduced in respect to the angulation fromstraight to angulated (17°) zircon abutment.


Article
Fracture Resistance of Premolars with Different Filling Techniques

Author: Ammar Kh Al–Nori
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2007 Volume: 7 Issue: SpIss Pages: S103-S108
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: To evaluate the fracture resistance of premolars with mesio–occluso–distal (MOD) preparations with resin composite using different incremental techniques when submitted to occlusal load. Materials and Methods: Fifty premolars were used and randomly divided into five groups of ten teeth each. The teeth in group I were prepared and not restored. The teeth in group II were restored in vertical technique. Teeth in group III were restored in horizontal technique. Teeth in group IV were restored in oblique technique. Teeth in groups II, III and IV were restored using Exite adhesive system and Tetric hybrid composite. Teeth in group V were restored in horizontal technique using combinations of Tetric flowable composite and Tetric hybrid composite. After thermocycling, the teeth were tested under universal compression machine. The data obtained in this research were subjected to analysis of variance and Duncan’s Multiple Range Test. Results: Both groups V and IV significantly increase the fracture resistance of teeth over groups II and III. Conclusions: Selection and appropriate use of materials, better placement technique and control polymerization shrinkage may increase the resistance of teeth to fracture with Class II resin composite restorations.


Article
The influence of CAD/CAM ceramic and heat processed composite inlays on the fracture resistance of premolars (An in-vitro study)

Authors: Huda A. Abdullah هدى عبد الله --- Inas I. Al-Rawi ايناس الراوي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: 4 Pages: 14-18
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The aim of this in-vitro study was to identify the influence of intracoronal indirect adhesive techniques(heat processed composite (SR Adoro) andcomputer-aided design / computer-assisted manufacturing (CAD/CAM)ceramic (e Max CAD) inlays)on the fracture resistance of maxillary first premolars and to identify the modes offracture of all experimental groups.Materials and Methods: Forty sound freshly extracted upper first premolar teeth were selected then mounted inacrylic blocks, the teeth were divided into four groupsas follow:Group (A): tenintact teeth (control group).Group (B):ten teeth prepared with standardized MOD inlay cavity but not restored. Group(C): ten teeth prepared withstandardized MOD inlay cavity and restored with indirect heat processed composite (SR Adoro).Group (D): ten teethprepared with standardized MOD inlay cavity and restored with CAD /CAM ceramic material (e max CAD).Fracturestrength of the experimented teeth was measured by using universal testing machine (an axial compressiontest).Data were analyzed statistically by ANOVA and least significant difference tests.Results:Group (D) restored with CAD/CAM ceramic inlays showed more resistance to fracture than teeth restoredwith SR Adoro composite inlays group (C), but the values are statistically not significant, using One way ANOVA test ahighly significant differences (P < 0.01) were found among all groups.Conclusions:All CAD/CAM ceramic inlays and 80% of heat processed compositeinlays survived maximum biting forcefor posterior single tooth, so these two types of inlays provide good reinforcement in an extensive MOD cavities inpremolars,The fracture Mode of SR Adoro composite inlays seems to be 80% restorable while CAD/CAM ceramicinlays 90% of it are restorable type of fracture


Article
Evaluation the Fracture Resistance of Endodontically Treated Teeth Restored With Different Post and Core Materials

Author: Biland M. Shukri بلند محمد شكري
Journal: Tikrit Journal for Dental Sciences مجلة تكريت لعلوم طب الاسنان ISSN: 20731213 Year: 2013 Volume: 2 Issue: 2 Pages: 110-116
Publisher: Tikrit University جامعة تكريت

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Abstract

Widespread use of prefabricated post that provides retention and support for core and the final crown has caused manufacturers to produce different types of post materials. The aim of this study was to evaluative the fracture resistance of two types of post materials and two types of core material. Forty extracted human mandibular premolar were selected. After root canal preparation and obturation with gutta percha the roots were divided into two groups according to the type of post material, group F restored with fiber post and group T restored with titanium post then each group was subdivided into two subgroup according to the type of core materials which include composite and amalgam restorative materials. Then all the teeth were subjected to compressive load at 130o angle from the horizontal plan at a 5mm/min crosshead speed until fracture. Results showed that there was significant different between groups in term of fracture loads (P= 0.0156). Also the fracture loads of teeth restored with titanium post and composite core has highest mean fracture load (812N), whereas teeth restored with fiber post and amalgam core demonstrated the lowest mean fracture load (643.1N). The study concluded that the teeth restored with metal titanium post were more fracture resistant than those restored with fiber posts. But the combination of a fiber post and composite core has the favorable mode of fracture that considered reparable, while considered unfavorable when restored with titanium post.


Article
Fracture resistance of endodontically treated premolars with extensive MOD cavities restored with different composite restorations (An In vitro study)

Authors: Aws H. Atiyah اوس عطيه --- Luma M. Baban لمى بابان
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 1 Pages: 7-15
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This in vitro study evaluated the fracture resistance of weakened endodontically treated premolars with class II MOD cavities restored with different composite restorations (Low-shrinkage Filtek P90, nanohybrid Filtek Z250 XT and SDR bulk fill). The type and mode of fracture were also assessed for all the experimental groups.Materials and Method: Fifty human adult maxillary premolar teeth were selected for this study. Standardized extensive class II MOD cavities with endodontic treatment were prepared for all teeth, except those that were saved as intact control. The teeth were divided into five groups of ten teeth each (n=10): (Group 1) intact control group, (Group 2) unrestored teeth with endodontic treatment, (Group 3) restored with (Filtek Z250 XT), (Group 4) restored with SDR bulk-fill flowable composite and (Group 5) restored with Filtek P90 composite. All specimens were subjected to compressive axial loading until fracture in a universal testing machine. The data were statistically analyzed using one-way ANOVA test and LSD test. Macroscopic fracture type were observed and classified into favorable and unfavorable. Specimens in group 3, 4 and 5 were examined by stereomicroscope at a magnification of 20× to evaluate the mode of failure into adhesive, cohesive or mixed.Results: The mean fracture load was (1.123 Kn) for group 1, (0.545 Kn) for group 2, (0.687 Kn) for group 3, (0.799 Kn) for group 4 and (0.672 Kn) for group 5. Using one way ANOVA test a highly significant difference (P < 0.01) were found among all groups. The use of bulk-fill flowable composite improved the fracture resistance significantly in comparison to silorane and non-significantly to Filtek Z250 XT. Filtek Z250 XT showed better improvement in fracture resistance but with no significant differences in comparison to Filtek P90 composite restorations. The type of failure was unfavorable for all the restored groups.Conclusion:All experimental composite restorations showed significant improvement in the resistance to cuspal fracture in comparison to unrestored one. However, under the conditions of this study, direct composite restorations should be considered as a valid interim restoration for weakened endodontically treated teeth before cuspal coverage can be provided.

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