(1) Background: External cervical resorption causes dental hard tissue destruction that may reduce the fracture resistance of affected teeth. By using a compressive strength test, this study aimed to evaluate the fracture resistance of teeth with simulated external cervical resorption cavities that have different three-dimensional classifications. (2) Methods: In total, 170 teeth with simulated external cervical resorptions were divided into 16 experimental groups (n = 10) and 1 control group (n = 10) based on the three-dimensional classification: 1Ap, 1Bp, 1Cp, 1Dp, 2Ap, 2Bp, 2Cp, 2Dp, 3Ap, 3Bp, 3Cp, 3Dp, 4Ap, 4Bp, 4Cp, 4Dp and a control group. Defects were restored with mineral trioxide aggregate. The fracture resistances of the samples were statistically analyzed using two-way repeated ANOVA and the Bonferroni correction for multiple comparisons at a significance level of p < 0.05. (3) Results: The lowest resistance to fracture was observed in samples with vertical height level “4” and circumferential spread of “D” (p < 0.001). In the groups with circumferential spreads “B”, “C” and “D”, there were significant differences between the samples with vertical height levels “1”, “2”, “3” and “4” regarding fracture resistance (p < 0.001). (4) Conclusions: The circumferential spread and vertical height of the external cervical resorption influenced the fracture resistance of the affected teeth.

Diabetes mellitus can alter the physical and mechanical properties of dentin, compromising bonding. Furthermore, residual sealer on dentin may inhibit the bond strength. The aim of this study was to evaluate and compare the effects of different cleaning protocols on the adhesive bond strength of composite to coronal dentin contaminated with a tricalcium silicate (TCS)based root canal sealer in diabetic and non-diabetic patients. Diabetic (n = 50) and non-diabetic (n = 50) teeth were randomly divided into two groups. Coronal dentin surface specimens were obtained. The samples were contaminated with a TCS based sealer and then divided into five subgroups, four different cleaning procedures (dry cotton, wet cotton, ultrasonic-15, ultrasonic-30) and a control group (n = 10). The samples were restored with composite. A standard shear bond strength (SBS) test was performed. All failures were categorized as adhesive, cohesive or mixed. Data were analyzed using Independent Samples t-test and One-Way Analysis of Variance at a significance level of p < 0.05. SBS values ​​were lower in diabetic dentin group than in non-diabetic dentin group. Dry cotton showed the lowest SBS value in both main groups. Ultrasonic-15 and ultrasonic-30 groups showed equal SBS values ​​in the non-diabetic group (p = 0.001), while the highest SBS was seen in the ultrasonic-30 subgroup in the diabetic dentin group. The highest adhesive failure was observed in the diabetic dentin group, and the dominant failure type was mixed for both groups. The use of dry cotton was an insufficient method for removing bioceramic root canal sealer residues from coronal dentin in both the diabetic and non-diabetic patients. 15 s of ultrasonic activation was effective for removing bioceramic root canal sealer remnants from the non-diabetic coronal dentin. However, for the coronal dentin in the diabetic group, 30-sec ultrasonic activation was the most effective method for removing bioceramic root canal sealer remnants.

This study evaluated the effect of resin cements and post-space irrigation solutions on the push-out bond strength of diabetic and non-diabetic dentin. A total of 160 human central teeth (80 diabetic, 80 non-diabetic) were prepared using X5 files and obturated with AH Plus sealer and X5 gutta-percha. Post spaces were prepared, and teeth were divided into eight groups based on resin cements (Variolink N, Panavia SA Universal) and irrigation protocols (saline, saline + 2% CHX). A 1 mm slice from each tooth’s middle third was tested for push-out bond strength. Statistical analysis was performed using three-way ANOVA and Tukey HSD tests. In non-diabetic dentin, saline + CHX with Variolink N achieved the highest bond strength. In diabetic dentin, saline with Panavia SA Universal resulted in the lowest bond strength (p < 0.05). The dentin type, resin cement, and irrigation solution significantly impacted fiber post bond strength, and CHX irrigation improved it.

(1) Background: Bond strength between repair and restorative materials is crucial for endodontic success. This study assessed the effects of the following final irrigation solutions on the bond strength of mineral trioxide aggregate (MTA) to a bulk-fill composite: (1) 17% Ethylenediamine tetraacetic acid (EDTA); (2) 2% Chlorhexidine (CHX); (3) 0.2% chitosan; (4) 0.2% chitosan with 2% CHX; 5) 0.2% chitosan with AgNPs. (2) Methods: Sixty MTA samples were divided into six groups (n = 10) based on the final irrigation solution: 1. EDTA, 2. CHX, 3. Chitosan, 4. Chitosan-CHX, 5. Chitosan-AgNP, and 6. distilled water (control). After a 5-min solution exposure, each sample was restored with the bulk-fill composite, and the shear bond strength (SBS) was measured. Structural changes in MTA were analyzed using SEM and EDS, and failure modes were classified as adhesive, cohesive, or mixed. Data were analyzed by one-way ANOVA with Tamhane’s T2 and Tukey’s tests (α = 0.05). (3) Results: EDTA exhibited the lowest SBS (p < 0.001), while Chitosan-CHX showed the highest. SEM showed a spongy, void-rich surface in EDTA-treated MTA, with significant Ca depletion per EDS. Chitosan-CHX showed no structural change. Cohesive fractures within MTA were predominant. (4) Conclusions: EDTA significantly reduces SBS, while chitosan with CHX enhances bond strength.

Amaç: Bu çalışmanın amacı kök kanal tedavisinde kullanılan farklı irrigasyon solüsyonlarının yüzey gerilimi değerlerini karşılaştırmaktır. Gereç ve Yöntem: %5.25 NaOCl, %9 HEBP, %2 PAA, %17 EDTA, %5.25 NaOCl + %9 HEBP, %5.25 NaOCl + %2 PAA, %5.25 NaOCl + %17 EDTA solüsyonlarının yüzey gerilimi değerleri damla şekli analiz cihazı DSA30 (Kruss, Hamburg, Almanya) ile ölçüldü. Her irrigasyon solüsyonu için 10 ayrı ölçüm yapıldı. Veriler mj/m2 cinsinden kaydedildi. Grupların ortalama ve standart sapma değerleri, tek yönlü ANOVA ve Bonferroni ve Tukey Çoklu Karşılaştırma Testleri yapılarak istatistiksel olarak değerlendirildi. Bulgular: En yüksek yüzey gerilim değerini %5.25 NaOCl + %2 PAA solüsyonu, en düşük değeri %9 HEBP solüsyonu gösterdi. %5.25 NaOCl+ %2 PAA grubunun yüzey gerilimi, %5.25 NaOCl, %9 HEBP, %2 PAA, %5.25 NaOCl+ %9 HEBP gruplarından istatistiksel olarak daha yüksekti (p0.05). Sonuç: Test edilen irrigasyon solüsyonları arasında %9 HEBP solüsyonu en düşük yüzey gerilimine sahipti.