Cristina Retana-Lobo1, Tatiana Ramírez-Mora1, Fabian Murillo-Gómez2, Juliane Maria Guerreiro-Tanomaru3, Mario Tanomaru-Filho3, Jessie Reyes-Carmona4. 1. Department of Endodontics, Faculty of Dentistry, LICIFO, University of Costa Rica, SJO, Sabanilla, San José, 11502, Costa Rica. 2. Dental Materials Research Laboratory, School of Dentistry, University of Costa Rica, SJO, Sabanilla, San José, 11502, Costa Rica. 3. Department of Restorative Dentistry, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP, Brazil. 4. Department of Endodontics, Faculty of Dentistry, LICIFO, University of Costa Rica, SJO, Sabanilla, San José, 11502, Costa Rica. jessreyesc@hotmail.com.
Abstract
OBJECTIVE: To evaluate the effect of several final irrigation protocols on radicular dentin microhardness, biochemical composition, and DMP1-CT expression. MATERIALS AND METHODS: A total of 140 single-rooted human teeth were prepared with WaveOne Gold files and randomly distributed into 7 groups (n = 20) according to the final irrigation protocol: distilled water (DW); sodium hypochlorite-EDTA (NaOCl-EDTA); EDTA (EDTA); EDTA-NaOCl (EDTA-NaOCl); EDTA-chlorhexidine (EDTA-CHX); passive ultrasonic irrigation (PUI:NaOCl-EDTA); and PUI:NaOCl-EDTA-NaOCl. Dentin microhardness (n = 10) was evaluated in the root canal lumen using Vickers hardness tester. Immunohistochemical analysis (n = 5) was used to evaluate DMP1-CT expression. Dentin ultrastructure and biochemical composition were evaluated by using Raman and energy dispersive X-ray analysis (EDAX) (n = 5) with a scanning electron microscope (SEM). Analysis of variance (ANOVA) and Tukey test were performed (p˂0.05). RESULTS: Raman spectra of the organic content and DMP1-CT expression were lower at the lumen canal in EDTA-NaOCl, PUI:NaOCl-EDTA, and PUI:NaOCl-EDTA-NaOCl when compared to control (p < 0.05). EDAX showed reduced values for calcium and phosphorus in EDTA-NaOCl, PUI:NaOCl-EDTA, and PUI:NaOCl-EDTA-NaOCl. SEM microphotography's showed completely cleaned dentin, permeable tubules, and dentin erosion, mainly when PUI was used. NaOCl-EDTA presented significantly higher microhardness values than PUI:NaOCl-EDTA-NaOCl (p < 0.05). PUI:NaOCl-EDTA-NaOCl exhibited the lowest Vickers hardness values of all groups. CONCLUSION: The final irrigation protocols that used a final rinse with NaOCl and PUI showed a detrimental effect on radicular dentin DMP1-CT expression, biochemical composition, and microhardness. CLINICAL RELEVANCE: The adequate irrigation protocol could be advantageous to preserve the radicular dentin ultrastructure, promote adequate adhesion, and sustain favorable conditions for biomineralization and regeneration.
OBJECTIVE: To evaluate the effect of several final irrigation protocols on radicular dentin microhardness, biochemical composition, and DMP1-CT expression. MATERIALS AND METHODS: A total of 140 single-rooted human teeth were prepared with WaveOne Gold files and randomly distributed into 7 groups (n = 20) according to the final irrigation protocol: distilled water (DW); sodium hypochlorite-EDTA (NaOCl-EDTA); EDTA (EDTA); EDTA-NaOCl (EDTA-NaOCl); EDTA-chlorhexidine (EDTA-CHX); passive ultrasonic irrigation (PUI:NaOCl-EDTA); and PUI:NaOCl-EDTA-NaOCl. Dentin microhardness (n = 10) was evaluated in the root canal lumen using Vickers hardness tester. Immunohistochemical analysis (n = 5) was used to evaluate DMP1-CT expression. Dentin ultrastructure and biochemical composition were evaluated by using Raman and energy dispersive X-ray analysis (EDAX) (n = 5) with a scanning electron microscope (SEM). Analysis of variance (ANOVA) and Tukey test were performed (p˂0.05). RESULTS: Raman spectra of the organic content and DMP1-CT expression were lower at the lumen canal in EDTA-NaOCl, PUI:NaOCl-EDTA, and PUI:NaOCl-EDTA-NaOCl when compared to control (p < 0.05). EDAX showed reduced values for calcium and phosphorus in EDTA-NaOCl, PUI:NaOCl-EDTA, and PUI:NaOCl-EDTA-NaOCl. SEM microphotography's showed completely cleaned dentin, permeable tubules, and dentin erosion, mainly when PUI was used. NaOCl-EDTA presented significantly higher microhardness values than PUI:NaOCl-EDTA-NaOCl (p < 0.05). PUI:NaOCl-EDTA-NaOCl exhibited the lowest Vickers hardness values of all groups. CONCLUSION: The final irrigation protocols that used a final rinse with NaOCl and PUI showed a detrimental effect on radicular dentin DMP1-CT expression, biochemical composition, and microhardness. CLINICAL RELEVANCE: The adequate irrigation protocol could be advantageous to preserve the radicular dentin ultrastructure, promote adequate adhesion, and sustain favorable conditions for biomineralization and regeneration.
Authors: Márcia Helena Wagner; Ricardo Abreu da Rosa; José Antonio Poli de Figueiredo; Marco Antonio Húngaro Duarte; Jefferson Ricardo Pereira; Marcus Vinicius Reis Só Journal: Clin Oral Investig Date: 2016-11-25 Impact factor: 3.573