Alpha-TCP is a biocompatible reactive ion-releasing calcium-phosphate able to provide calcium and phosphate ions due to its biodegradation by hydrolysis and progressive dissolution. Alpha-TCP could enhance/improve the apatite-forming ability of calciumsilicate portland-derived hydraulic cements currently used in endodontics and oral surgery. Aim: An innovative calcium-silicate hydraulic self-setting cement containing alphatricalcium phosphate (alpha-TCP) has been conceived and designed for dentistry. The kinetic of the in vitro apatite formation was studied in simulated body fluids. Materials & methods: An experimental calcium-silicate portland-derived cement containing di- and tricalcium-silicate and alpha-TCP (wTC-TCP) was designed and prepared. The same cement free from alpha-TCP was used as control (wTC). The cements were soaked in different phosphate-containing solutions, namely Dulbecco’s Phosphate Buffered Saline (DPBS) or Hank’s Balanced Salt Solution (HBSS), at 37°C and the surface chemistry was investigated over time (from 24hrs to 6months) by SEM/EDX, micro-Raman and ATR-FTIR. Results: The early formation (24hrs) of an aragonite/calcite layer onto both cements in both media was observed. Calcium phosphate deposits precipitated within 1-3days in DPBS; spherical calcium-phosphate particles (apatite spherulites) appeared after 3-7days. wTC-TCP cement showed earlier, thicker and more homogeneous calcium phosphate deposits than wTC. In HBSS calcite deposits were mainly noticed, while phosphate bands appeared only after 7days; the presence of globular deposits after 14-28days was mostly detected on wTC-TCP. After 6months, an approx 900microns carbonated apatite layer formed in DPBS whilst a 150-350microns thick calcite/apatite layer generated in HBSS. Even in HBSS the carbonated apatite coating was earlier and thicker on wTC-TCP than wTC. Conclusions: Calcium-silicate cements showed the formation of a bone-like apatite layer, depending on the medium composition and ageing time. The addition of alpha-TCP increases the apatite-forming ability of calcium-silicate cements. Calcium-silicate hydraulic cements doped with alpha-TCP represent attractive materials to improve apical bone healing in oral surgery.
M.G. Gandolfi, P. Taddei, A. Tinti, S.O. Akintoye, C. Prati (2011). Alpha-TCP improves the apatite-forming ability of calcium-silicate hydraulic cements soaked in phosphate solutions..
Alpha-TCP improves the apatite-forming ability of calcium-silicate hydraulic cements soaked in phosphate solutions.
GANDOLFI, MARIA GIOVANNA;TADDEI, PAOLA;TINTI, ANNA;PRATI, CARLO
2011
Abstract
Alpha-TCP is a biocompatible reactive ion-releasing calcium-phosphate able to provide calcium and phosphate ions due to its biodegradation by hydrolysis and progressive dissolution. Alpha-TCP could enhance/improve the apatite-forming ability of calciumsilicate portland-derived hydraulic cements currently used in endodontics and oral surgery. Aim: An innovative calcium-silicate hydraulic self-setting cement containing alphatricalcium phosphate (alpha-TCP) has been conceived and designed for dentistry. The kinetic of the in vitro apatite formation was studied in simulated body fluids. Materials & methods: An experimental calcium-silicate portland-derived cement containing di- and tricalcium-silicate and alpha-TCP (wTC-TCP) was designed and prepared. The same cement free from alpha-TCP was used as control (wTC). The cements were soaked in different phosphate-containing solutions, namely Dulbecco’s Phosphate Buffered Saline (DPBS) or Hank’s Balanced Salt Solution (HBSS), at 37°C and the surface chemistry was investigated over time (from 24hrs to 6months) by SEM/EDX, micro-Raman and ATR-FTIR. Results: The early formation (24hrs) of an aragonite/calcite layer onto both cements in both media was observed. Calcium phosphate deposits precipitated within 1-3days in DPBS; spherical calcium-phosphate particles (apatite spherulites) appeared after 3-7days. wTC-TCP cement showed earlier, thicker and more homogeneous calcium phosphate deposits than wTC. In HBSS calcite deposits were mainly noticed, while phosphate bands appeared only after 7days; the presence of globular deposits after 14-28days was mostly detected on wTC-TCP. After 6months, an approx 900microns carbonated apatite layer formed in DPBS whilst a 150-350microns thick calcite/apatite layer generated in HBSS. Even in HBSS the carbonated apatite coating was earlier and thicker on wTC-TCP than wTC. Conclusions: Calcium-silicate cements showed the formation of a bone-like apatite layer, depending on the medium composition and ageing time. The addition of alpha-TCP increases the apatite-forming ability of calcium-silicate cements. Calcium-silicate hydraulic cements doped with alpha-TCP represent attractive materials to improve apical bone healing in oral surgery.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
