Vertical root fracture resistance of simulated immature permanent teeth filled with MTA using different vehicles

The aim of the study is to evaluate the resistance vertical root fracture (VRF) of mineral trioxide aggregate (MTA) filled-immature permanent roots by using three different vehicles. Forty-extracted human single-rooted mandibular premolars were selected and the root length was standardized to the length of 9 mm. For simulation of immature tooth apices, peeso reamers were introduced into the root canals and the prepared roots were assigned into three experimental groups according the used vehicle (distilled water-DW, prophylene glycol-PG, chlorhexidine-CHX) and control group (n=10). To simulate a periodontal membrane, the apical 7 mm of all roots was covered with wax to obtain a 0.2- to 0.3-mm-thick layer before embedding the roots into acrylic cylinders. A vertical force was applied (1mm/min) using a universal testing machine and the maximum load (F-max) that fracture occurred and the fracture mode (splint or comminuted) was recorded. Data were presented as mean and standard deviations. Statistical analysis was performed using Kruskal-Wallis, Mann-Whitney U Test was used for multiple comparisons. There were significant differences between fracture strength of experimental groups with that of control group (p0.05). In all groups, split fracture was the most common fracture mode. MTA increases resistance of immature permanent teeth to VRF. Based on the results of this study, it can be concluded that mixing MTA with CHX or PG as the vehicle do not alter VRF resistance of simulated immature permanent roots

Concentration And Time-Dependent Effect Of Initial Sodium Hypochlorite On The Ability Of Qmix And Ethylenediaminetetraacetic Acid To Remove Smear Layer

Aims: The aim of this study was to compare the ability of 17% ethylenediaminetetraacetic acid (EDTA) and QMix with different concentrations and time exposures of initial sodium hypochlorite (NaOCl) to remove the smear layer from the root canals. Materials and Methods: Eighty maxillary central incisors were used. After instrumentation, the teeth were divided into eight experimental groups according to the initial and final rinse. About 2.5% and 5% NaOCl were used during instrumentation and for 1 or 3 min was used as postinstrumentation initial irrigants, and 17% EDTA and QMix used as final irrigants. The apical and middle parts of the specimens were observed by scanning electron microscope. Statistical Analysis Used: Data were analyzed using the Kruskal–Wallis, Mann–Whitney, and Friedman's test. Results: Regardless of the type of final irrigant, QMix allowed more smear layer removal than EDTA after using 5% initial NaOCl for 3 min. In the apical part of the root canal walls, the smear layer was not completely removed. Conclusion: QMix and EDTA were similarly effective in smear layer removal at the middle parts of the root canal regardless of the concentration and time exposure of initial NaOCl, while none of the irrigation protocols was able to remove smear layer at the apical parts.PubMe

A Case Series Associated with Different Kinds of Endo-Perio Lesions

Pulpal and periodontal problems are responsible for more than half of the tooth mortality. There are some articles published in the literature about this issue. Many of them are quite old. There has been also lack of knowledge about the effect of endodontic treatment on the periodontal tissue healing and suitable treatment interval between endodontic and periodontal treatments. In this case report, different kinds of endo-perio lesion were treated with sequential endodontic and periodontal treatment. The follow-up radiographs showed complete healing of the hard and soft tissue lesions. The tooth with endo-perio lesions should be evaluated thoroughly in terms of any cracks and fracture, especially furcation areas for a long term prognosis. In this case report, it was showed that 3 months treatment intervals between endodontic treatment and periodontal surgery has no harmful effect on periodontal tissue healing. , Key words:Endo-perio lesion, furcation, mandibular molar, bone graft, crack line, treatment interval.PubMedScopu

Comparison Of Triple Antibiotic Paste Removal By Different Irrigation Techniques

This study compared different irrigation techniques in triple antibiotic paste (TAP) removal from root canals. Fifty-six maxillary anterior -teeth were filled with TAP for 28 days, and assigned into 5 experimental groups (n=10): Syringe irrigation (SI), NaviTip FX (NFX), Vibringe-Syringe irrigation (V-SI), NaviTip FX-Vibringe (V-NFX), passive ultrasonic irrigation (PUI) and positive and negative control groups (n=3 for each). Following the removal of the medicament, the remaining medicament was evaluated using 4-grade scoring-system. V-NFX and NFX showed similar performances (p>0.05) while V-NFX was significantly more efficient than SI and PUI (p0.05). Regarding different parts of the root canals, V-SI and PUI were significantly less efficient at the apical part (p<0.05). In conclusion, the brush form of irrigation delivery with and without sonic activation improved the removal of TAP from the root canals when compared to ultrasonic activation, syringe irrigation or sonic activation alone.WoSScopu

Effect of Placement Technique on The Push-Out Bond Strength of Calcium-Silicate Based Cements

The purpose of this study was to evaluate the effects of ultrasonic and manual placement techniques on the push-out bond strength of Biodentine and MTA with and without calcium chloride. One hundred and twenty mid-root slices from forty freshly extracted single-rooted human mandibular premolar teeth were instrumented and randomly divided into six groups (n=20) according to the filling material and placement technique applied, as follows: Gl: MTA-manual compaction, G2: Biodentine-manual compaction, G3: MTA+5% CaCl2-manual compaction, G4: MTA-ultrasonic activation, G5: Biodentine-ultrasonic activation, G6: MTA+5% CaCl2 ultrasonic activation. The push-out bond strengths were measured using an Instron testing machine. Data were analyzed using twoway analysis of variance (ANOVA) with Bonferroni correction. The ultrasonic activation significantly enhanced the bond strength values of the materials. Biodentine presented higher bond strength values than that of MTA groups. The addition of CaCl2 to MTA did not improve the bond strength of the material.WoSScopu

Koronal Bariyer Kalınlığının Gelişimi Tamamlanmamış Dişlerin Kırılma Dayanımına Etkisi

Amaç: Rejeneratif endodontik tedavi görmüş vakalarda kök kırıklarının en önemli nedenlerinden biri travmadır. Bu çalışmanın amacı, bariyer materyali olarak farklı kalınlıklarda yerleştirilen Biodentine’in gelişimi tamamlanmamış dişlerin kırılma dayanımına etkisini incelemektir. Gereç ve Yöntem: Gelişimi tamamlanmamış diş simulasyonu için, 65 adet üst santral dişin kök kanalları Peeso reamerlar ile genişletildi. On dişte giriş kavitesi açılmadı ve bunlar negatif kontrol grubu olarak ayrıldı. Giriş kavitesi açılmış 55 dişin, 10 tanesi pozitif kontrol olarak ayrıldı ve bu dişlerin kök kanalına kalsiyum hidroksit yerleştirildi. Kök kanallarına yerleştirilen Biodentine’in kalınlığına göre 45 diş rastgele olacak şekilde 3 gruba ayrıldı (n=15); Grup 1: 2-3 mm kalınlıkta koronal bariyer, Grup 2: 5-6 mm kalınlıkta koronal bariyer, Grup 3: tüm kanalın dolumu. Bekleme süresi sonrası, kırılma dayanımı analizi universal test cihazı ile gerçekleştirildi. Tek yönlü varyans analizi ve Tukey testleri ile istatistiksel analiz yapıldı. Bulgular: Pozitif kontrol, Grup 1 ve Grup 2 arasında anlamlı fark yoktu (P &gt; 0.05). Negatif kontrol ve Grup 3 en yüksek kırılma dayanımı değerlerini gösterdi (P &lt; 0.05) ve bu iki grup arasında anlamlı fark yoktu (P &gt; 0.05). Tüm kırıklar dişlerin servikal kısmında yatay veya eğik olarak meydana geldi. Sonuçlar: Biodentine koronal bariyer olarak kullanıldığında dişlerin kırılma dayanımı üzerinde güçlendirici bir etkisi olmadı. Kök kanalı tamamen Biodentine ile doldurulduğunda en iyi güçlendirme etkisi oluştu. Koronal bariyer kalınlığının gelişimi tamamlanmamış dişlerin kırılma dayanımına herhangi bir etkisi olmadı

Surface and vertical dimensional changes of mineral trioxide aggregate and biodentine in different environmental conditions

Abstract Surface changes in biological environments are critical for the evaluation of physical and biological activity of biomaterials. Objective: This study investigated surface alterations of calcium silicate-based cements after exposure to different environments. Material and Methods: Forty-eight cylindrical cavities were prepared on root surfaces. The cavities were filled using ProRoot MTA or Biodentine and assigned to four subgroups (n=6): dry, wet, acidic, and blood. Surface topographies were evaluated using an optical profilometer for 28 days, and the roughness of the material surfaces was quantified. Vertical dimensional change was measured by determining the height difference between the material surface and the flat tooth surface. Data were compared with a two-way repeated measures ANOVA and Bonferroni tests. Results: In dry condition, the surface roughness of MTA or Biodentine was constant up to 3 days (p>0.05) but decreased after 28 days (p0.05). Both materials showed the highest roughness in blood conditions on the 1st day (p<0.05), while the surface roughness in blood decreased dramatically after 28 days. The roughness of Biodentine was higher in wet conditions up to 3 days compared with ProRoot MTA (p<0.05). Likewise, in blood condition, Biodentine showed higher roughness on the 28th day than ProRoot MTA (p<0.05). Conclusions: Dry, wet, and blood conditions had a time-dependent effect on the surface roughness and vertical dimensional changes of the materials. However, acidic conditions did not affect the roughness and the surface level of the materials

TANNİK ASİTLE İRRİGASYONUN KÖK KANAL DENTİNİNİN MİKSROSERTLİĞİNE VE EPOKSİ REZİN ESASLI PATIN BAĞLANMA DAYANIMINA ETKİSİ

Background:To investigate the effects of final irrigation protocols with tannic acid (TA) on dentin microhardness and push-out bond strength of an epoxy resin based sealer to root canal dentin.Methods: The 50 root halves were embedded in an acrylic resin for the microhardness measurement. After the initial baseline microhardness measurement, the root halves were randomly divided into 5 groups according to the final irrigation protocol used (n=10): distilled water (control), 10% TA for 2 min, 10% TA for 5 min, 20% TA for 2 min, and 20% TA for 5 min. After surface treatment, dentin microhardness values were recorded at close proximity to the initial indentation areas. For push-out bond strength test the root canals of 75 single-rooted mandibular premolars were instrumented and the final irrigation protocols were applied as described above (n = 15). Following root canal obturation with single cone technique using matched-taper  gutta percha cones and an AH Plus- epoxy resin based root canal sealer, 1 mm-thick slices were obtained from the middle third of the root canals. Push-out bond strength test was applied. The data were analyzed using One way ANOVA and Tukey HSD tests (p=0.05).Results:In TA-treated groups, there was a significant increase in the microhardness values compared with the control group (p&lt;0.05). Regarding the push-out bond strength test, there was no significant difference between the bond strength values of 10% TA for 2 min and the control group (p&gt;0.05). The remaining groups presented higher bond strength values than the control group (p&lt;0.05).Conclusions: TA increased dentin microhardness and the bond strength of the epoxy resin based sealer to root canal dentin. The effect on the bond strength was time and concentration dependent. Keywords: bond strength, dentin, microhardness, epoxy resin based sealer, tannic aci

A Miniature Swine Model For Stem Cell-Based De Novo Regeneration Of Dental Pulp And Dentin-Like Tissue

The goal of this study was to establish mini-swine as a large animal model for stem cell-based pulp regeneration studies. Swine dental pulp stem cells (sDPSCs) were isolated from mini-swine and characterized in vitro. For in vivo studies, we first employed both ectopic and semi-orthotopic study models using severe combined immunodeficiency mice. One is hydroxyapatite-tricalcium phosphate (HA/TCP) model for pulp-dentin complex formation, and the other is tooth fragment model for complete pulp regeneration with new dentin depositing along the canal walls. We found that sDPSCs are similar to their human counterparts exhibiting mesenchymal stem cell characteristics with ability to form colony forming unit-fibroblastic and odontogenic differentiation potential. sDPSCs formed pulp-dentin complex in the HA/TCP model and showed pulp regeneration capacity in the tooth fragment model. We then tested orthotopic pulp regeneration on mini-swine including the use of multi-rooted teeth. Using autologous sDPSCs carried by hydrogel and transplanted into the mini-swine root canal space, we observed regeneration of vascularized pulp-like tissue with a layer of newly deposited dentin-like (rD) tissue or osteodentin along the canal walls. In some cases, dentin bridge-like structure was observed. Immunohistochemical analysis detected the expression of nestin, dentin sialophosphoprotein, dentin matrix protein 1, and bone sialoprotein in odontoblast-like cells lining against the produced rD. We also tested the use of allogeneic sDPSCs for the same procedures. Similar findings were observed in allogeneic transplantation. This study is the first to show an establishment of mini-swine as a suitable large animal model utilizing multi-rooted teeth for further cell-based pulp regeneration studies.Wo