Advanced search
Start date

Influence of the functionalization of calcium orthophosphate particles on the mechanical properties of experimental composites

Grant number: 20/04537-2
Support type:Scholarships in Brazil - Scientific Initiation
Effective date (Start): September 01, 2020
Effective date (End): March 31, 2021
Field of knowledge:Health Sciences - Dentistry - Dental Materials
Principal Investigator:Roberto Ruggiero Braga
Grantee:Amanda Lopes Campos
Home Institution: Faculdade de Odontologia (FO). Universidade de São Paulo (USP). São Paulo , SP, Brazil


The functionalization of dicalcium phosphate dihydrate (DCPD) particles with triethylene glycol dimethacrylate (TEGDMA) is an effective resource to minimize the negative effects of the incorporation of calcium phosphate in remineralizing materials. However, there is doubt as to whether the greatest fracture resistance observed in materials containing functionalized DCPD particles is due to the establishment of a matrix-particle interface capable of resisting crack propagation or reducing the effective DCPD content in the material, once that in these particles part of its mass (or volume) is occupied by the monomer. OBJECTIVE: to evaluate the influence of the incorporation of DCPD on the degree of conversion, mechanical strength and flexural modulus of composites containing functionalized and non-functionalized DCPD particles. The null hypothesis will be tested that materials with the same effective content of DCPD present similar results in relation to the studied variables. METHODS: Non-functionalized DCPD particles will be synthesized by the co-precipitation method and later functionalized with TEGDMA. The particles will be incorporated into a resinous matrix in a fraction of 50 vol%. Ten groups will be formed according to the proportion between DCPD (functionalized, F, or non-functionalized, NF) and barium glass (vol%): 50: 0, 40:10, 30:20, 20:30, 10: 40 and 0:50. In addition, a control group (50% glass, without DCPD) will be tested. The materials will be evaluated for the degree of conversion (FTIR) and resistance to biaxial flexion / flexural modulus after 24 hours of storage in water. The results will be analyzed using the statistical tests most appropriate to the sample distribution found, with a significance level of 5%. (AU)