Influence of photodynamic therapy on the bond strength of glass fiber posts to radicular dentin

• Grant number: 15/06056-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2015
• End date: July 31, 2016
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Gustavo Sivieri de Araújo
• Grantee: Paloma Pereira da Silva
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

Photodynamic therapy (PDT) is an aggregate of physical, chemical and biological procedures that occur after use of photosensitizer (PS) which is active by visible light, with a specific wavelength, to aim to destroy the target cells. Actually, strong evidences show the efficacy on microorganism reduction promotes by PDT, however there is no studies on literature show the influence of PDT on mechanical proprieties of the intraradicular dentin. The aim of the study will be to evaluate the influence of PDT on the bond strength of glass fiber posts in different thirds of intraradicular dentin (cervical, middle and apical), through the push-out test. For this study forty freshly extracted bovine incisors will be used. Previous x-ray will be performed to confirm the integrity of the tooth structure. The biomechanical preparation in all root canals with K file, which the final instrument a K #80, 1 mm short of root apex and irrigation with 1% sodium hypochlorite. The five group (n=8) will be distribute: G1-control (deionized water); G2-curcumin PS 500 mg/L; G3-curcumin PS 500 mg/L + blue Led (PDT); G4-curcumin PS 1000 mg/L; G5-curcumin PS 1000 mg/L + blue Led (PDT). Both groups (G2 to G5) will receive curcumin PS for 5 minutes (pre-irradiation period) mixed with ultrasound by 60 seconds passive irrigation (without refrigeration) on endodontic scale 2 and a K file #25 positioned 2mm before the working length. On G3 and G5, the curcumin PS will be activated with Led » 480 nm, 75 J/cm² fluency, by four minutes, helped by an optical fiber with a 500-¼m diameter length positioned 2mm before the working length. Then all root canals will be dried and filled, using a main #80 guta-percha cone and accessory cones F and MF. Root canal will be prepared for receive glass fiber posts White DCE #2 (FGM), once will be cemented into to the root canal with RelyX U200 (3M Espe) self-adhesive resin cement. The bond strength will be measured using the push-out test in a universal assay machine on the three parts of intracanal dentin (cervical, middle and apical). The data will be submitted to normality test and the means will be compared by specific statistical tests (±=0.05). Representative samples of each group will be analyzed with scanning electron microscopy.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

STRAZZI SAHYON, HENRICO BADAOUI; DA SILVA, PALOMA PEREIRA; DE OLIVEIRA, MURILO SILVA; ANGELO CINTRA, LUCIANO TAVARES; GOMES-FILHO, JOAO EDUARDO; DOS SANTOS, PAULO HENRIQUE; SIVIERI-ARAUJO, GUSTAVO. Effect of photodynamic therapy on the mechanical properties and bond strength of glass-fiber posts to endodontically treated intraradicular dentin. JOURNAL OF PROSTHETIC DENTISTRY, v. 120, n. 2, AUG 2018. (15/06056-3)

STRAZZI SAHYON, HENRICO BADAOUI; DA SILVA, PALOMA PEREIRA; DE OLIVEIRA, MURILO SILVA; ANGELO CINTRA, LUCIANO TAVARES; DEZAN-JUNIOR, ELOI; GOMES-FILHO, JOAO EDUARDO; JACINTO, ROGERIO DE CASTILHO; DOS SANTOS, PAULO HENRIQUE; SIVIERI-ARAUJO, GUSTAVO. Influence of curcumin photosensitizer in photodynamic therapy on the mechanical properties and push-out bond strength of glass-fiber posts to intraradicular dentin. Photodiagnosis and Photodynamic Therapy, v. 25, p. 376-381, MAR 2019. (15/06056-3)

DE OLIVEIRA, MURILO SILVA; DA SILVA, PALOMA PEREIRA; DE MELO, FERNANDA SANTOS; TEIXEIRA MARTINEZ, CAROLINA MARTINS; ANGELO CINTRA, LUCIANO TAVARES; GOMES-FILHO, JOAO EDUARDO; DOS SANTOS, PAULO HENRIQUE. Does photodynamic therapy with methylene blue affect the mechanical properties and bond strength of glass-fiber posts in different thirds of intraradicular dentin?. Photodiagnosis and Photodynamic Therapy, v. 30, JUN 2020. (15/06056-3)