Flexural strength of Y-TZP dental ceramic after different grinding procedures and resintered

• Grant number: 11/11509-6
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2011
• End date: October 31, 2013
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Ligia Antunes Pereira Pinelli
• Grantee: Ligia Antunes Pereira Pinelli
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated researchers: Gelson Luis Adabo ; José Maurício dos Santos Nunes Reis ; Laiza Maria Grassi Fais ; Renata Garcia Fonseca

Abstract

This study will evaluate the influence of different grinding procedure associated or not with resintering of zirconia on the flexural strength, hardness and roughness of yttria-stabilized polycrystalline zirconia (Y-TZP). Seventy two bar-type zirconia specimens divided into two groups will be made: Group 1 (G1, control, n = 24) is composed of specimens with dimensions of 20mm x 4mm x 1.2 mm. In group 2 (G2, n = 48), specimens with dimensions of 20mm x 4mm x 1.5 mm will have 0.3 mm of their surfaces grinding horizontally at high speed with diamond burs to zirconia, including (subgroup a, n = 24) or not (subgroup b, n = 24) irrigation with water spray. The temperature variations of these surfaces will be measured by means of a Laser Sighted Non-Contact Temperature Probe. In both groups, half of the samples (G1 = 12, G2a = 12, G2b = 12) will be subjected only to flexural strength (FS) at four-point bending testing in the machine EMIC DL 2000 (5 kN, 0.5 mm/min) while the other half will be resintering (1000°C for 30 minutes) prior to testing. The average surface roughness (Ra, um) and hardness (VHN) of the samples will also be evaluated, respectively, by profilometer and microhardness tester. For surface and microstructural characterization of Y-TZP zirconia, samples will be analyzed by X-ray diffraction and scanning electron microscopy. The data will be submitted to the most appropriate statistical test to ascertain whether the implementation of the damage and whether the resintering may interfere with the evaluated properties. (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)

HATANAKA, GABRIEL R.; POLLI, GABRIELA S.; FAIS, LAIZA M. G.; REIS, JOSE MAURICIO DOS S. N.; PINELLI, LIGIA A. P.. Zirconia changes after grinding and regeneration firing. JOURNAL OF PROSTHETIC DENTISTRY, v. 118, n. 1, p. 61-68, JUL 2017. (11/11509-6)

OBELENIS RYAN, DANIEL PATRICK; GRASSI FAIS, LAIZA MARIA; ANTONIO, SELMA GUTIERREZ; HATANAKA, GABRIEL RODRIGUES; CANDIDO, LUCAS MIGUEL; PEREIRA PINELLI, LIGIA ANTUNES. Y-TZP zirconia regeneration firing: Microstructural and crystallographic changes after grinding. DENTAL MATERIALS JOURNAL, v. 36, n. 4, p. 447-453, AUG 2017. (13/21438-4, 11/11509-6)