Effect of sodium hypochlorite and edta irrigation, individually and in alternation, on dentin microhardness at the furcation area of mandibular molars

Abstract

The aim of this study was to evaluate the effect of irrigation regimens on dentin microhardness at the furcation area of mandibular molars, using sodium hypochlorite and ethylenediaminetetraacetic acid (EDTA), individually and in alternation. The occlusal surface and the roots of 20 non-carious extracted human permanent mandibular molars were cut transversally and discarded. The tooth blocks were embedded in acrylic resin and randomly assigned to 4 groups (n=5) according to the irrigating regimens: 1% NaOCl solution, 17% EDTA solution, 1% NaOCl and 17% EDTA and distilled water (control). Knoop microhardness of dentin at the furcation area was evaluated. Data were analyzed using one-way ANOVA and Tukey's multiple comparison tests (α=0.05). The results of this study indicated that all irrigation solutions, except for distilled water (control), decreased dentin microhardness. EDTA did not show a significant difference with NaOCl/EDTA (p>0.05), but showed a significant difference with NaOCl (p<0.01). EDTA and NaOCl/EDTA showed a maximum decrease in microhardness. The 17% EDTA solution, either alone or in combination with 1% NaOCl reduced significantly dentin microhardness at the furcation area of mandibular molars.

Influence of root dentin treatment on the push-out bond strength of fibre-reinforced posts

“…Measurement of microhardness is only possible on smooth dentin surfaces because the indentations are not visible on nonpolished surfaces 22 . Dentin microhardness was measured with a Knoop indenter (Shimadzu HMV-2000; Shimadzu Corporation, Kyoto, Japan) under 10-g load and 15-second dwell time.…”

Consideration of the Therapeutic Potential of Irrigants in Endodontic Therapy

“…As a result of collagen and glycosaminoglycan degradation, NaOCl may affect the hardness, flexural strength and elasticity of the root dentin (43)(44)(45)(46).…”

Effect of different rotary systems on fracture resistance of post-core reconstructed teeth

“…35 NaOCl ve EDTA irigasyon solüsyonları üzerine yapılan bir çalışmada, dentin mikro sertliğinin her iki solüsyonun kullanımında da düştüğü ancak diğer bir çalışma grubu olan distile suyun dentinin mikrosertliğini üzerine etkisinin olmadığını vurgulamışlardır. 36 Yapılan başka bir araştır-mada da farklı konsantrasyonlarda kullanılan NaOCl'nin kök dentini üzerindeki yapısal ve mekanik etkileri incelenmiş, çalışma sonucunda distile su ve %1 konsantrasyonundaki NaOCl'nin kök dentininin esneklik dayanımı ve elastik modülünde kayda değer bir değişikliğe neden olmadığını belirtmişlerdir. 37 Çalışmamızda da, in vivo koşulları elde edebilmek ve daha sağlıklı sonuçlar ortaya koymak amacıyla tüm gruplarda eşit miktarda %1 konsantrasyonunda NaOCl solüsyonu ile irrigasyon yapıldı.…”