Abstracts Book - IMRC 2018

• SE2-P070
EFFECT OF CITRIC ACID AND GELATIN BINDERS ON THE
MECHANICAL STRENGTH OF HYDROXYAPATITE-BASED
BIOCEMENTS
Jorge López Cuevas 1 , Gregorio Vargas Gutiérrez 1 , José Luis Rodríguez Galicia 1 , Juan Carlos
Rendón Angeles 1
1 Centro de Investigación y de Estudios Avanzados del IPN - CINVESTAV, Ceramics Engineering,
Mexico.
The great similarity of hydroxyapatite, Ca 10 (PO 4 ) 6 (OH) 2 , to the inorganic
constituent of human bones, places this calcium phosphate amongst the
materials having the best characteristics required for biomedical applications.
One of the most promising applications of hydroxyapatite is in the fabrication
of biocements with controllable setting times at 37 ºC. However, hydroxyapatite
based-biocements developed up to now are brittle, which makes them useful as
space fillers only. In the present study, aiming to control the setting reaction and
to increase the strength of hydroxyapatite-based biocements, citric acid and
gelatin were used as binders. The biocements were characterized by SEM and
their mechanical strength was measured after 1 to 15 days of exposure to a
100% relative humidity at 37 ºC. The addition of citric acid produced compressive
strengths of about 16 MPa and diametral tensile strengths of ~2 MPa, regardless
of the aging time. In the case of gelatin-bound biocements, the aging time had
a very strong effect on the mechanical properties, giving compressive strengths
of 20-40 MPa and diametral tensile strengths of 2-12 MPa. The combined
addition of citric acid and gelatin has not resulted in additional improvements in
the mechanical strength of the biocements.
Keywords: biocements, hydroxyapatite, organic binders
Presenting authors email: jorge.lopez@cinvestav.edu.mx