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Titanium (Ti) implants are extensively used in a number of biomedical and dental applications.This work introduces Ti into the glass phase of a zinc based Glass Polyalkenoate Cement (GPC) and investigates changes in handling and mechanical properties considering two molecular weight polyacrylic acids (PAA), E9 and E11. Considering the handling properties, the working time (T w ) increased from 50s E9 , 32s E11 (BT 101, Ti-free) to 169s E9 , 74s E11 with TW-Z (highest Ti content) respectively. The setting time (T s ) increased from 76s E9 , 47s E11 (BT 101) to 303s E9 , 232s E11 with TW-Z respectively. Ti was also found to have a significant increase on both compressive (σ c ) and biaxial flexural strength (σ f ), where σ c increased from 36 MPa E9 , 56 MPa

Lanthanum and neodymium incorporation in simplified high level waste glasses has been investigated for SiO 2– B 2 O 3– Na 2 O – Al 2 O 3– CaO compositions quenched from 1200°C, for varying La /( La  +  Nd ) (atomic) and increasing rare‐earth oxides contents. In this system and beyond the solubility limit, rare‐earths (RE) elements are reported to form apatite phases with the general formula Ca 2 RE 8( SiO 4)6 O 2. In the current study, speciation of these trivalent RE 3+ cations in both amorphous network and crystal phases was determined from X‐ray diffraction, scanning electron microscopy, optical absorption at 10 K, Raman spectroscopy, and electron probe microanalysis. It appeared that RE 2 O 3 solubility was higher for La ‐rich formulations than for Nd ‐rich ones and that an increase in the RE oxide content reduces the connectivity of the network building units through formation of non‐bridging oxygens at the expense of the oxygen bridges. This depolymerization of the glass network did not affect neodymium environment which consisted in silicate tetrahedra. The composition of the apatite crystals was found to be affected by the La /( La  +  Nd ) of the parent glass and deviation from the ideal composition ( Ca 2 RE 8( SiO 4)6 O 2) occurred in the neodymium end of the system. It thus appears that both RE 2 O 3 solubility and crystal composition are strongly dependent on the type and crystal chemistry of the RE elements.