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Öğe Are dentin posts biomechanically intensive?: A laboratory and FEA study(Taylor & Francis, 2014) Belli, Sema; Çelik, Kezban; Akbulut, Makbule Bilge; Güneşer, Mehmet Burak; Eraslan, Oğuz; Eskitaşcıoğlu, GürcanThe goal of this laboratory and finite elemental stress analysis (FEA) study was to compare fracture strength of dentin post (DP) with stainless steel and glass fiber posts. Single-rooted teeth were decoronated and restored with ParaPost (PP), i-TFC (TFC), and DPs (n=10). Resin cores were created and loaded until failure (1.0mm/min). The data were analyzed (ANOVA, Tukey, Chi-Square tests). Three-dimensional FEA models of the posts were created and the stress distributions were calculated using Solid Works/Cosmos works structural analysis program. A significant difference was found among the groups (p<0.001). TFC group showed the highest and the DP group showed the lowest fracture resistance (p<0.001). PP created more stress at the root dentin and inside the post. Restoration of roots with glass fiber and DPs may reduce stresses within the core material and the remaining root. However, a fracture-resistant restoration cannot be achieved by using a DP.Öğe Effects of intracanal medicaments and the remaining cavity wall on fracture strength of endodontically treated molars(Universidade Estadual Paulista, Institute of Science and Technology of Sao Jose dos Campos, 2018) Olcay, Keziban; Çoban, Ata Nisa; Belli, SemaObjective: The aim of this study was to investigate the effects of the short-term intracanal application of two medicaments on the fracture strength of root-filled molar teeth with different levels of tooth structure loss. Material and Methods: Standard access cavities of totally 84 intact maxillary molar teeth were prepared in 72 teeth and were divided into 3 main groups. Standard access cavities were vkept in the first group, while mesio-occlusal-distal cavities (MOD) were prepared in the second and third groups. One-half of the palatinal walls were removed in the third group. Twelve sound teeth were used in the fourth group as control. Each group was then assigned into two subgroups according to the medicament used (n=12): 2% chlorhexidine gel and calcium hydroxide. Samples were stored at 37°C and 100% humidity for 1 week. Then the teeth were inserted into a universal testing machine and vertically loaded (5 mm/min) from the occlusal surface. The data was recorded in Newtons and statistically evaluated using a Univariate ANOVA and a Tukey as post hoc test. Results: A significant difference was found among the test groups (p<0.01). No significant difference was found according to the medicament used (p>0.05), however the number of remaining walls significantly affected the fracture strength (p<0.01). The first group with access cavity showed mostly repairable fractures (60%–80%) whereas the others showed mostly nonrepairable fracture patterns (60%–90%). Conclusion: In conclusion, the fracture strength of endodontically treated teeth is related to the structure loss rather than the intracanal medicament used.Öğe Endodontik sebeplerle çekilmiş dişlerin mineral içeriğinin SEM-EDX yöntemi ile incelenmesi(2016) Olcay, Keziban; Ataoğlu, Hanife; Belli, SemaEndodontik sebeplerle çekilmiş dişlerin mineral içeriğinin SEM-EDX yöntemi ile incelenmesi Amaç:Bu araştırmanın amacı; endodontik tedavi sonrasında diş dokularının mineral içeriğinde meydana gelen değişikliklerin, dişin farklı bölgelerinde Taramalı Elektron Mikroskobu-Enerji Dağılımlı X Işını Analizi (SEM-EDX) yöntemi kullanılarak incelenmesidir. Gereç ve Yöntemler: Bu çalışmada başarısız olmuş kanal tedavili dişler arasından çekim endikasyonu konulan, 20 adet tek köklü insan daimi dişi ve 20 adet kök kanal tedavisi görmemiş, ortodontik veya periodontal nedenlerle çekilmiş, çürüksüz, restorasyonsuz, sağlam tek köklü insan daimi dişi olmak üzere toplam 40 adet diş kullanılmıştır. Dişler kanal tedavisi sonrasında yapılarındaki mineral miktarında olası değişikliklerin endodontik tedavide başarısızlık ile ilişkisinin araştırılması amacıyla SEM-EDX analizine gönderilmek üzere %10'luk formalin solüsyonunda bekletildi. SEM-EDX analizi sırasında, her dişin bir yarısı, apikal, orta ve koronal olmak üzere standardize edilmiş 3 ayrı noktadan, elementel içerik ve elementel dağılım açısından 300 büyütme altında analiz edildi. Dişin diğer yarısı ölçüm amacıyla kullanılmadı. Bu analiz sırasında, oksijen, karbon, kalsiyum, fosfor, magnezyum, sodyum, sülfür, çinko, alüminyum, klor ve Ca/P ile ilgili veriler değerlendirildi. SEM-EDX ile elde edilen verilerin istatistiksel analizi ise tek yönlü varyans analizi ile yapıldı. Bulgular: SEM-EDX analizinin sonuçlarına göre kök kanal tedavisi olan dişler ve kontrol grubu arasında karbon, kalsiyum, fosfor, alüminyum ve klor ile ilgili anlamlı fark bulunmuştur (p<0,01). İki grup arasında oksijen, magnezyum, sodyum, sülfür, çinko ve Ca/P miktarı ile ilgili anlamlı bir fark bulunamamıştır (p>0,05). Apikal, orta ve koronal bölgeler açısından hiçbir grupta anlamlı bir farklılık yoktur (p>0,05). Sonuç: Bu çalışmada, kök kanal tedavisi sonrasında, dişin farklı bölgelerinde bir fark gözlenmezken, diş dokusunda karbon, kalsiyum, fosfor, alüminyum ve klor mineralleri açısından anlamlı farklılıklar olduğu sonucuna varılmıştır.Öğe Evaluation of related factors in the failure of endodontically treated teeth: A cross-sectional study(Elsevier Science Inc, 2018) Olcay, Keziban; Ataoğlu, Hanife; Belli, SemaIntroduction: The aim of this study was to review the factors related to the failure and extraction of unsuccessful endodontically treated teeth. Methods: A total of 1000 teeth treated with nonsurgical root canal therapy were analyzed, and the following information was recorded for each patient: reasons for failure and extraction, type of tooth, presence and type of coronal restoration, smoking status, age, gender, and level of education. One main reason was recorded for each failed tooth. The associations between reasons for failure, patient, and tooth were tested by using chi(2) analysis. Results: Of the 1000 endodontically failed teeth analyzed in this study, 28.1% (n = 281) were extracted, 66% (n = 660) were re-treated, and 5.9% (n = 59) were treated with apical surgery. Among the reasons for failure, restorative and endodontic reasons were seen most frequently (43.9%, n = 439), whereas orthodontic reasons were seldom seen (0.1%, n = 1). The most common reason for extraction was for prosthetic reasons (40.8%), and perforation/stripping was the least common (2.9%). The mandibular first molars were the most frequently extracted teeth (27.4%, n = 77). Conclusions: The most common reason for the extraction of endodontically treated teeth was for prosthetic reasons. Among the reasons for failure, restorative and endodontic reasons were the most frequently seen, and orthodontic reasons were the most seldom. The teeth that failed most frequently were mandibular first molars, and the teeth that failed least frequently were maxillary third molars. The most common reason for the extraction of failed endodontically treated teeth was for prosthetic reasons.Öğe Polytetrafluoroetylene tape as temporary restorative material: A fluid filtration study(Istanbul University Press, 2015) Olcay, Keziban; SteIer, Liviu; Erdoğan, Hilal; Belli, SemaPurpose: The purpose of this study was to compare the sealing ability of temporary restorative materials at 24 hrs and 1 week. Materials and Methods: Endodontic access cavities were prepared in 56 extracted lower incisor-teeth and divided into 5 groups (n=10). Standard 5 mm deep access preparations were completed and root canals were prepared to size ISO # 30 file. The access cavities were restored as follows: Group 1: temporary restorative material (Ceivitron); Group 2: glass ionomer cement (Fuji II); Group 3: zinc oxide-eugenol cement (IRM); Group 4: zinc phosphate cement (Adhesor); Group 5: polytetrafluoroetylene tape (PTFE). The quality of the coronal sealing of each specimen was measured (24 hrs and 1 week) using fluid transport model. The data was analysed with repeated measurements of ANO VA, Tukey, Paired samples T-Tests. Results: A significant difference was found among the groups at all time-periods (p<0.05). At 24 hrs, PTFE showed similar leakage with Ceivitron, IRM, and Fuji II but it showed higher leakage than Adhesor. At 1 week, Ceivitron showed higher leakage than PTFE, meanwhile PTFE showed similar leakage with IRM, Fuji II, and Adhesor (p>0.05). Sealing ability of IRM and PTFE groups significantly increased by time (p<0.05 and p<0.001 respectively). Conclusion: Within the limitations of this study, PTFE showed an acceptable short-term sealing capability when compared to the other commonly used temporary restorative materials at 1 week measurements.Öğe Prevalence of vertical root fracture in extracted endodontically treated teeth: A prospective study(Cumhuriyet University Faculty of Dentistry, 2017) Olcay, Keziban; Ataoğlu, Hanife; Belli, SemaObjectives: Vertical root fracture (VRF) is one of the complications of endodontic treatment which results extraction of the related tooth. The purpose of this prospective study was to evaluate prevalence of VRF in extracted endodontically treated teeth. Materials and Methods: During a 1 year period 241 teeth were observed. All of the cases were from extracted teeth after endodontic treatment. Clinical signs, symptoms, the informations about patient and related tooth were recorded. Results: A total of 17 (7.02%) cases of VRF occurring among 241 cases were observed. The VRF occurred most frequently in the mesial roots of the mandibular first molars (23.5%) and they were the most frequently extracted teeth (35.2%). The VRF prevalence of maxillary first molars was 23.5%, maxillary first and second premolars with a same frequency (11.7%) were the following most fractured teeth. The fractures were predominantly buccolingual and were more frequent in female patients (58.8%). The mean patient age was 36 years and the mean time to VRF was 45 months. Most of the teeth which undergo VRF had a composite restoration (41.1%). 23.5% of the teeth had a post restoration and from among these posted teeth 75% were fully crowned. VRF was found similar frequency in mandibular teeth and in maxillary teeth (p > 0.05). Conclusions: After average of 45 months from endodontic treatment, mandibular first molar teeth were found most frequently prone to extraction due to VRF. Further investigation is necessary to determine the possible causes and evidence of fracture development.Öğe The effect of boric acid on root dentin mineral content and bond strength of AH-plus: A SEM-EDX study(Turkiye Klinikleri, 2016) Akman, Melek; Belli, Sema; Olcay, Keziban; Özçopur, BetülTo investigate the effects of boric acid, EDTA and citric acid on rootdentin mineral content and on shear-bond strength of AH Plus. Material and Methods: Eighteen extracted mandibular premolars were used. The crowns were removed. The roots were then longitudinally sectioned under water cooling to obtain two root halves from each tooth. Element levels were examined by SEM-EDX and build-ups were created using AH Plus. The element levels and shear-bond strength data (MPa) were recorded. After shear-test, the root surfaces were re-grounded, and subjected to 5,25% NaOCl followed by 10% Boric acid, 17% EDTA and 10% Citric acid. The root surfaces were re-examined by SEM-EDX. Shear-test was repeated. The element levels and shear-bond strength data (MPa) were recorded and analyzed by using paired samples t test. Results: Boric acid increased O, Na, K and Ca/P ratio (p<0.001), did not change Ca, C, Mg contents of root-dentin (p>0.05). EDTA increased O, Na, C, Ca/P ratio (p<0.001), decreased the Ca, P, S (p<0.001). Citric acid increased C, Na, Ca/P ratio (p<0.001), decreased Ca, P, S contents (p<0.05). Citric acid did not change shear-bond strength of AH Plus (p=0.218). Both Boric acid and EDTA treatment decreased shear bond strength of the sealer (p=0.000). Conclusion: All the tested materials changed the mineral contents of root dentin. Boric acid and EDTA treatment decreased shear bond strength of AH Plus. Boric acid might be considered as an alternative chelating agent however further experimental and clinical evaluations are needed to use the material safely.Öğe The effect of different restoration techniques on fracture strength of teeth with flared roots(Taylor and Francis, 2015) Çelik, Keziban; Belli, SemaThe aim of this study was to investigate the effect of different restoration techniques on the fracture strength of roots with flared canals. The crowns of 50 extracted single-rooted human teeth were removed and the canals were flared. Five groups were created (n=10): Group 1: ReforPost (Angelus) was luted using Clearfil SA Cement (Kuraray); Group 2: ReforPost and two accessory posts (Reforpin, Angelus) were luted with Clearfil SA Cement; Group 3: Restored with i-TFC post-core system (Sun Medical); Group 4: The thickness of the root-dentine was increased using composite resin (Clearfil AP-X, Kuraray) and cured with the help of Luminex. ReforPost was then luted; Group 5: Anatomic posts were created by relining ReforPost with Clearfil AP-X and then luted using Clearfil SA Cement. The cores were created with composite resin in all the samples. The crowns of sound teeth were prepared similar to a core (control, n=10). The specimens were vertically loaded (1mm/min), the force that was required to fracture each sample was recorded (N) and analyzed (One Way Anova, Tukey tests). No significant difference was found among the groups (p>0.05). The roots restored by using accessory post and i-TFC post-core (Groups 2 and 3) indicated a 100% favorable fracture pattern. Ten percent of the root fractures were observed in other groups. All techniques saved the root structure and showed 80-100% favorable failure pattern. The use of i-TFC system in flared roots could be an alternative to anatomic, accessory, and prefabricated fiber posts.
