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Article
Tensile Strength of Core Build up Material to Glass Fiber Post with Different Surface Treatment

Author: Eman M. Yahya
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2017 Volume: 17 Issue: 33 Pages: 1-11
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: The purpose of this study was to investigate the effects of different surface treatments on the tensile retentive force of fiber reinforced posts (FRPs) to composite core material buildup. Materials and methods: A total of fifty FRPs were randomly divided into five groups (n = 10), the first group was the untreated control group, second group immersion in 24% hydrogen peroxide; third group immersion in 4% hydrofluoric acid gel; fourth group sandblasting with 50um Al2O3 powder, fifth group surface preparation with an Er:YAG laser under power setting (300m), at 2 Hz and 100 uS) for 10 seconds. A cylindrical polyethylene mold was used to surround the treated posts, and the mold was filled with dual cure composite core material buildup. All samples were light cured for 40 seconds through the top of the mold. After 24 hours of storage in water, the post was then grasped with Jacobs chuck attached to the upper member of testing machine and produced tensile loading. Tensile tests were performed at a cross, head speed of 0.5 mm/minute using a universal testing machine. Data were analyzed by One-Way Analysis of Variance followed by Duncan Multiple Range Test at significant difference (p < 0.05). Results: The post core tensile retentive force achieved following pretreatment with hydrogen peroxide and sandblast (Groups 2 and 4) were comparable to each other, and significantly higher than those of other groups in which the post surface had been treated with hydrofluoric acid gel, control group and laser, respectively. Conclusions: surface pretreatment of FRP has significance effect on the tensile retentive force. Sandblasting and hydrogen peroxide are increasing tensile retentive force of FRPs to composite core material buildup greater than those of hydrofluoric acid gel, control and laser group, respectively.


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
Comparative study of retention of fiber-reinforced post at middle and cervical one thirds of root canal cemented by polycarboxylate and zinc phosphate cements measured at different storage times

Author: Saad Zabar سعد زبار
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 2 Pages: 41-46
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The purpose of this study was to compare regional bond strength at middle and cervical thirds of theroot canal among glass fiber-reinforced composite (FRC) endodontic posts cemented with different cements, usingthe push-out test to compare the performance (retention) of two types of luting cements; polycarboxylate cementand Zinc phosphate cement used to cement translucent fiber post and to compare the result of the push-out testat different storage times;1 week ,1month and 2 months.Materials and methods: Ninety caries-free, recently extracted single-rooted human teeth with straight root canalswas used in this study, The root canals were endodontically instrumented at a working length of 0.5 mm from theapex by means of conventional instruments for hand use (Dentsply, Switzerland) up to size 35.then root canal fillingwas performed followed by post space preparation up to 8mm including cervical and middle one third of root canalthen the fiber post was cemented into canal post space then the root was sectioned to get cervical (4 mm inlength) and middle (4 mm in length) thirds ,these thirds were examined by push out test to get values of retention offiber post inside these canal thirds .Results and Conclusions: The results of this study has been showed that there was no significant differences betweenpush out bond strength between fiber post and root at cervical third as compared with middle third when usingpolycarboxylate cement or Zinc phosphate cement to cement the fiber post to the canal walls and the resultsshowed that there was no significant differences in push out bond strength for polycarboxylate or Zinc phosphatecement after one and two months but there was highly significantly increase in push out bond strength for resincements used to cement the fiber post to the root canal after one and two months


Article
Comparative Study of Retention of Fiber-Reinforced Post Retention At Middle and Cervical Thirds of Root Canal Cemented by Different Luting Cements

Author: Mohammed R., M.Sc.,P.H.D.
Journal: Journal of University of Babylon مجلة جامعة بابل ISSN: 19920652 23128135 Year: 2013 Volume: 21 Issue: 7 Pages: 2589-2596
Publisher: Babylon University جامعة بابل

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Abstract

The purpose of this study was to compare regional bond strength at middle and cervical thirds of the root canal among glass fiber-reinforced composite (FRC) endodontic posts luted with different cements, using the push-out test. To compare the performance (retention) of two types of luting cements polycarboxylat cement and Glass ionomer cement used to cement translucent fibre post. and To compare the result of the push-out test at different storage times;1 week ,1month and 2 months. Sixty caries-free, recently extracted single-rooted human teeth with straight root canals will be used in this study, The Roots endodontically instrumented canals were at a working length of 0.5 mm from the apex by means of conventional instruments for hand use (Dentsply, Switzerland) up to size 35.then root canal filling was performed followed by post space preparation up to 8mm including cervical and middle one third of root canal then the fibre post was cemented into canal post space then the root was sectioned to get cervical (4 mm in length) and middle (4 mm in length) thirds ,these thirds were examined by push out test to get values of retention of fiber post inside these canal thirds .The results of this study showed that there was no significant differences between push out bond strength between fiber post and root at cervical third as compared with middle third when using polycarboxylate cement to cement the fiber post to the canal walls but there was highly significant differences between push out bond strength between fiber post and root at cervical third as compared with middle third when using glass ionomer cement also the results showed that the glass ionomer cement. The results also shwed that the push out bond strength for GIC was higher than that of PCC and that the push out retention of GIC incrases with time,while no such changes occur with PCC.

ترمي هذه الدراسة إلى معرفة مدى تأثير نوعين من المواد الاسمنية على ثبات الوتد الشفاف المعزز بالألياف داخل عاج قناة جذر السن في المنطقة العلوية والمنطقة الوسطية لجذر الأسنان وخلال فترات حفظ مختلفة (أسبوع واحد وشهر واحد وشهرين).أظهرت النتائج انه لا يوجد اختلاف بين ثبات الوتد الشفاف المعزز بالألياف داخل عاج قناة جذر السن في المنطقة العلوية والمنطقة الوسطية لجذر الأسنان عند استخدام مادة البولي كربوكسليت الاسمنتية في حين هناك اختلاف كبير بين ثبات الوتد الشفاف المعزز بالألياف داخل عاج قناة جذر السن في المنطقة العلوية فهو أكثر ثبات من المنطقة الوسطية لجذر الأسنان عند استخدام مادة الكلاس اينمير الاسمنتية. وكذالك أظهرت النتائج أن هنالك فرقاً كبيراً أكثر ثباتاً للوتد الشفاف المعزز بالألياف داخل عاج قناة جذر السن عند استخدام مادة الكلاس اينمير الاسمنتية مقارنة بثبات الوتد الشفاف المعزز بالألياف داخل عاج قناة جذر السن عند استخدام مادة البولي كربوكسليت الاسمنتية. وكذالك أظهرت النتائج ان جفظ العينان لفترة أطول قد زاد ثبات الوتد الشفاف المعزز بالألياف داخل عاج قناة جذر السن عند استخدام مادة الكلاس اينمير الاسمنتية فقط.


Article
Comparison of fit among different types of post restorations luted with conventional cement

Authors: Ehsaan S. Al-Mustwfi --- Haitham J. Al-Azzawi
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 3 Pages: 14-18
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: with the advent of new postmaterial in dentistry, it has become important to measure fitness of postrestoration along the horizontal plane of the root space.This study aimed to measure and compare, the cement filmthickness of conventional zinc phosphate cement in micrometer between the post and root dentin along horizontalplane at different post space regions (coronal, middle and apical) of four types of posts, by using stereomicroscopy.Material and methods: Thirty-two extracted human maxillary canines, mandibular canines and maxillary centralincisors (n=32) were instrumented with ProTaper system files (hand use) and obturated with gutta-percha for ProTaperand AH26® root canal sealer. After 24hrs of incubation at 37ºC, post space was prepared using FRC Postec® plusdrills no.3 and ER Cera reamer size 70, creating 10 mm deep post space. The prepared samples were then randomlydivided into four main groups (8 samples each) according to the type of post used (Group A: fabricated cast metalpost), (Group B: fabricated zirconia post), (Group C: prefabricated glass fiber reinforced composite post), (Group D:prefabricated zirconia post). After cementation and incubation period of 24hrs, each root was sectioned horizontallyinto 3 discs (2mm in thickness) at the coronal, middle and apical regions of the root space. The cement thicknessbetween post and root dentine was measured (in μm) by using a stereomicroscope.Results: The results of this study showed that the lowest mean of cement thickness was in group C (35.28μm), followedby group A (78.12μm) and group D (81.9μm), and all three groups demonstrated acceptable cement thickness,while group B produced unacceptable cement thickness (127.34μm). One way ANOVA test revealed a statisticallyhighly significant difference for the cement thickness among four post types used within each region of the root.Conclusions: the root region and type of post system have an effect on cement thickness along post space


Article
Comparison of regional bond strength of post space of fiber-reinforced post luted with two types of cements at different testing times

Authors: Haitham J. Al-Azzawi --- M.N.H.
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 3 Pages: 19-23
Publisher: Baghdad University جامعة بغداد

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Abstract

Back ground: This in vitro study was carried out to investigate the effect of post space regions (coronal, middle andapical), Time and the mode of polymerization (dual, self-cured) of the cements used on the bond strength betweentranslucent fiber post and root dentin by using push-out test.Materials and Methods: Forty eight extracted mandibular first premolars (single root) were instrumented with ProTaperUniversal system files (for hand use) and obturated with gutta percha for ProTaper and AH26® root canal sealerfollowing the manufacturer instructions, after 24 hours post space was prepared using FRC postec® plus drills no.3creating 8 mm depth post space. The prepared samples were randomly divided into two main groups (24 sampleseach) according to the used cement (Group M, self-cure, Multilink N) and (Group R, dual cure, Relyx U100). Theneach group was subdivided into three groups (each group contains 8 samples) according to the testing time aftercementation. (g M1: push out test after 24 hour of cementation with Multilink N), (g M2: push out test after one weekof cementation with Multilink N),(g M3: push out test after two weeks of cementation with Multilink N), (g R1: push outtest after 24 hours of cementation with RelyxU100), (g R2: push-out test after one week of cementation withRelyxU100), (g R3: push out test after two weeks of cementation with RelyxU100). After cementation and incubationeach root was sectioned horizontally into 3 slices (2 mm in thickness) represent the coronal, middle and apicalregions of the post space. Push out bond strength test was performed and measured using a universal testingmachine (Tinius-Olsen) at across head speed of 0.5 mm/min.Results: showed that regarding the root region, the bond strength values increased significantly apical to coronalregion in both tested cements. For the effect of time, the bond strength values also significantly increased with timefor both tested cements. For mode of polymerization, the self-cured resin cement Multilink N showed higher bondstrength values.Conclusion: the retention of fiber post was affected by root region, mode of polymerization of the cements usedand time elapsed after cementation of the post


Article
Comparison of regional bond strength among different types of posts luted with different types of cement

Authors: Ahmed A. Al-Jumaily احمد الجميلي --- Haitham J. Al-Azzawi, هيثم العزاوي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 1 Pages: 1-6
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This in vitro study was carried out to investigate the effect of post space regions (coronal, middle and apical), the effect of post types ( Manually Milled Zirconia post, Prefabricated Fiber post, prefabricated Zirconia post) and the type of cement used (GIC, self-adhesive resin cement) on the bond strength between the posts and root dentin by using push-out test.Material and methods: Forty eight mandibular premolars extracted for orthodontic reasons (single rooted) were instrumented with ProTaper system (hand use) and obturated with gutta percha for ProTaper using AH26® root canal sealer following the manufacturer instructions. After 24 hours, post space was prepared using Zirix and Glassix drills no.3 creating 8 mm depth post space. The prepared samples were randomly divided into three main groups (16 samples each) according to the type of post used (Group A. Manually Milled Zirconia post, Group B. Prefabricated Fiber post and Group C. Prefabricated Zirconia post) .each group was subdivided into two subgroups (each subgroup contains 8 samples) according to the type of cement used (subgroup A1.Manually Milled Zirconia post cemented with GIC, subgroup A2.Manually Milled Zirconia post cemented with Speed cem),( subgroup B1.Prefabricated Fiber post cemented with GIC, Group B2. Prefabricated Fiber post cemented with Speed cem) and (subgroup C1.Prefabricated Zirconia post cemented with GIC, subgroup C2. Prefabricated Zirconia post cemented with Speed cem), after cementation and incubation for 24hrs, at 37°c and 100% humidity. Each root was sectioned horizontally into 3 slices (2 mm in thickness) representing the coronal, middle and apical regions of the post space. Push out bond strength test was performed and measured using a universal testing machine (Tinius-Olsen) at across head speed of 0.5 mm/min.Results: The results showed that regarding the root region, the bond strength values increased significantly from apical to coronal region for all types of posts in both tested cements. For the effect of post type, the manually Milled Zirconia post cemented with the self-cured resin cement (Speed cem) showed higher bond strength values. For type of cement, the self-adhesive resin cement (Speed cem) showed higher bond strength values.Conclusions: the retention of post restoration was affected by root region, type of post and type of cement used

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