Selective caries removal using Er:YAG laser and rewetting dentin with chitosan solution

• Grant number: 14/23654-9
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): March 01, 2015
• Effective date (End): February 28, 2018
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Acordo de Cooperação: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Silmara Aparecida Milori Corona
• Grantee: Fabiana Almeida Curylofo Zotti
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Front the benefits of selective caries removal using Er:YAG laser and attempting to overcome their possible interference in the adhesion process of resinous materials, it becomes relevant to assess the incorporation of a biopolymer (chitosan) in caries-affected dentin to allow an improvement in structural integrity and increased strength of bonding interface longitudinally. The general objective is to evaluate the effect of selective caries removal using Er:YAG laser and dentin rewetting with chitosan solution, as well as evaluate adhesive interface longitudinally. This study will be divided into two experiments: Experiment 1: will aim to evaluated the effect of selective caries removal using Er:YAG laser (250mJ/4Hz) followed by the treatment with chitosan solution in remineralization ability of dentin and in the resistance to collagen degradation. Sample will be composed of 112 bovine incisors submitted to artificial caries induction by pH-cycling method (8h in demineralizing solution and 16h in remineralizing solution). Selective caries removal will be realized with Er:YAG laser or 1:1 L low-speed handpiece (convectional method). Teeth will be etched with phosphoric acid at 37% and, then, will be divided according to rehydration of dentin collagen matrix: without rehydration (control) and rehydration with chitosan solution at 0.2% for 3 minutes. Levels of calcium and phosphorus by energy dispersive X-ray spectroscopy (EDS), degradation of dentin collagen measured by hydroxyproline (HYP) release, dry mass percentage and surface morphology using scanning electron microscopy (SEM) will be analyzed in the samples. Experiment 2: will aim to evaluated the effect of selective caries removal using Er:YAG laser (250mJ/4Hz) followed by the treatment with chitosan solution in resin/dentin interface after 24h, 6 and 18 months subjected to thermic and enzymatic challenges. Sample will be composed of 288 bovine incisors submitted to artificial caries induction by pH-cycling method (8h in demineralizing solution and 16h in remineralizing solution). Selective caries removal will be realized with Er:YAG laser or 1:1 L low-speed handpiece (convectional method). Teeth will be etched with phosphoric acid at 37% and, then, will be divided according to rehydration of dentin collagen matrix: without rehydration (control) and rehydration with chitosan solution at 0.2% for 3 minutes. Dentin surface will be restored using adhesive (Adper Single Bond 2 - 3M) and resin composite. Specimens will be divided according to the aging time of the adhesive interface: no degradation of adhesive interface (tests conducted after 24 hours storage in water) and degradation of adhesive interface after 6 months (tests conducted after 6 months storage in water + 12000 cycles of thermocycling + enzymatic degradation) or 18 months (tests conducted after 18 months storage in water + 36000 cycles of thermocycling + enzymatic degradation). Specimens will be submitted to tests of microtensile bond strengths and dentin microhardness and analysis of nano-infiltration of the adhesive interface by means of confocal laser scanning microscopy. For both studies, the selection of statistical tests will be based on the characteristics of the data set for each variable. The statistical inferences will be made considering the significance level of 5%. (AU)

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)

CURYLOFO-ZOTTI, FABIANA ALMEIDA; SALLES SCHEFFEL, DEBORA LOPES; MACEDO, ANA PAULA; DE SOUZA-GABRIEL, ALINE EVANGELISTA; HEBLING, JOSIMERI; MILORI CORONA, SILMARA APARECIDA. Effect of Er:YAG laser irradiation and chitosan biomodification on the stability of resin/demineralized bovine dentin bond. JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS, v. 91, p. 220-228, MAR 2019. (14/23654-9)

CURYLOFO-ZOTTI, FABIANA A.; FERNANDES, MARIA P.; MARTINS, AMANDA A.; MACEDO, ANA PAULA; NOGUEIRA, LUCAS FABRICIO B.; RAMOS, ANA PAULA; CORONA, SILMARA A. M.. Caries removal with Er:YAG laser followed by dentin biomodification with carbodiimide and chitosan: Wettability and surface morphology analysis. MICROSCOPY RESEARCH AND TECHNIQUE, v. 83, n. 2, OCT 2019. (14/23654-9)

CURYLOFO-ZOTTI, FABIANA A.; TANTA, GABRIELA SOLANO; ZUCOLOTO, MIRIANE LUCINDO; SOUZA-GABRIEL, ALINE E.; CORONA, SILMARA A. M.. Selective removal of carious lesion with Er:YAG laser followed by dentin biomodification with chitosan. Lasers in Medical Science, v. 32, n. 7, p. 1595-1603, SEP 2017. (14/23654-9)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

ZOTTI, Fabiana Almeida Curylofo. Selective caries removal using Er:YAG laser and dentin biomodification with chitosan. 2018. Doctoral Thesis - Universidade de São Paulo (USP). Faculdade de Odontologia de Ribeirão Preto (PCARP/BC) Ribeirão Preto.