ABSTRACT
The reactivity of acid base cements forming hydroxyapatite (HA) such as, β-tricalcium phosphate (β-TCP) and dicalcium phosphate dehydrate (DCPD). Amorphous calcium phosphates, prepared by precipitation from supersaturated solutions, can also react to form apatitic cements since they are thermodynamic unstable with respect to HA and have a setting reaction more independent of particle size. Calcium phosphate cement containing an antibiotic can be used for filling bone defects and to ensure local antibiotherapy. Therefore, in the present chapter proposal, cement paste were prepared by combining cement liquids comprised of Na2HPO4 with cement powders. Gentamicin sulfate was also loaded on the cements and its in vitro release was evaluated over a period of time. The cement setting times were compared before and after drug addition. According to results, the initial and final setting times of samples increase after drug addition.
Keywords: Biphasic, Bone cement, Injectability, Gentamicin sulfate, Drug release, β-tricalcium phosphate, Hydroxyapatite, Mechanical properties, Porosity, Calcium phosphate cement
INTRODUCTION
Calcium phosphate materials are widely applied as a variety of bone substitute materials in dental and medical fields. Brown and Chow in 1986 were firstly developed calcium phosphate cements (CPCs). Calcium phosphate cement is a group of calcium phosphate ceramic which has excellent biocompatibility and bioactivity properties. It is suitable to be used only for non- or low load-bearing applications such as bone filler (Friedman et al., 1998; Kamerer et al., 1994; Constantz et al., 1995) bone augmentation (Horstmann et al., 2003; Strauss & Egol, 2007; Liverneaux, 2004; Welch, Zhang & Bronson, 2003; Aral et al., 2008) and drug delivery applications (Ginebra, Traykova & Planell, 2006). CPCs exhibit various benefits comparing other calcium phosphate based materials. Being injectable and easy to shape let them to be used to fill geometrically complicated bone defects (Del Real, Wolke, Vallet‐Regí, & Jansen, 2002). Reactants for HA cements are crystalline calcium phosphates like tetracalcium phosphate (TTCP) or α/β-tricalcium phosphate (α/β-TCP) combined with slightly acidic compounds like dicalcium phosphate anhydride (DCPA) or dicalcium phosphate dehydrate (DCPD). On account of distinctive rates of disintegration of reactants, setting responses will just happen if the dynamic solubilities of all segments are harmonious; subsequently, this is ordinarily balanced by means of the particle size/particular surface range of the reactant particles. The powder stage after blending with a fluid stage like water or a watery arrangement shapes a glue which in light of the solidifying response can frame HA (apatite cements) or DCPD (brushite cements) in the wake of being connected inside of the body (Julien et al., 2007), (Kokubo, 2008), (Van den Vreken et al., 2010), (Ginebra, Traykova & Planell, 2006), (Yang, Troczynski & Liu, 2002). Cements formed at pHs age and the component of contamination. Bacterial reasons for intense and direct Osteomyelitis incorporate group related methicillin-safe Staphylococcus Aureus (MRSA), Kingella Kingae and others. Treatment for osteomyelitis includes the start of intravenous anti-infection agents that enter bone and joint depressions, referral of the patient to an orthopedist or general surgeon and conceivable restorative irresistible illness meeting (King & Kulkarni, 2010). Couple of confusions in reconstructive orthopedics represents a more difficult hindrance to clinical accomplishment than disease, and bacterial osteomyelitis remains an imperative and overwhelming orthopedic and clinical issue. An assortment of prophylactic and helpful systems has been intended to decrease the occurrence and effect of disease. Routine treatment utilizing systemic anti-microbials is costly, inclined to complexities and frequently unsuccessful. In this way, neighborhood treatment is craved to treat or avert osteomyelitis (Lew & Waldvogel, 2004; Ciampolini & Harding, 2000). Gentamicin is an aminoglycosidic antibiotic for bacterial infections caused by staphylococcus which …show more content…
Gentamicin solution with the concentrations of 0.1%, 0.5% and 1.0% were prepared. The model drug solution concentrations were analyzed via UV-Visible Spectrophotometer (Hitachi UV U3010) at 290 nm peak absorbency to obtain the respective absorbance values. The wavelength at 290 nm was determined as the peak absorbency wavelength as maximum absorbency at this particular wavelength was observed. The equation of the linear curve shown in Table 1 and Figure 1 produced with the three points of different concentrations was used to quantify the concentrations of gentamicin in the withdrawn sample solutions. Drug release profiles for the different sets of implants up to 14 days were
The reactivity of acid base cements forming hydroxyapatite (HA) such as, β-tricalcium phosphate (β-TCP) and dicalcium phosphate dehydrate (DCPD). Amorphous calcium phosphates, prepared by precipitation from supersaturated solutions, can also react to form apatitic cements since they are thermodynamic unstable with respect to HA and have a setting reaction more independent of particle size. Calcium phosphate cement containing an antibiotic can be used for filling bone defects and to ensure local antibiotherapy. Therefore, in the present chapter proposal, cement paste were prepared by combining cement liquids comprised of Na2HPO4 with cement powders. Gentamicin sulfate was also loaded on the cements and its in vitro release was evaluated over a period of time. The cement setting times were compared before and after drug addition. According to results, the initial and final setting times of samples increase after drug addition.
Keywords: Biphasic, Bone cement, Injectability, Gentamicin sulfate, Drug release, β-tricalcium phosphate, Hydroxyapatite, Mechanical properties, Porosity, Calcium phosphate cement
INTRODUCTION
Calcium phosphate materials are widely applied as a variety of bone substitute materials in dental and medical fields. Brown and Chow in 1986 were firstly developed calcium phosphate cements (CPCs). Calcium phosphate cement is a group of calcium phosphate ceramic which has excellent biocompatibility and bioactivity properties. It is suitable to be used only for non- or low load-bearing applications such as bone filler (Friedman et al., 1998; Kamerer et al., 1994; Constantz et al., 1995) bone augmentation (Horstmann et al., 2003; Strauss & Egol, 2007; Liverneaux, 2004; Welch, Zhang & Bronson, 2003; Aral et al., 2008) and drug delivery applications (Ginebra, Traykova & Planell, 2006). CPCs exhibit various benefits comparing other calcium phosphate based materials. Being injectable and easy to shape let them to be used to fill geometrically complicated bone defects (Del Real, Wolke, Vallet‐Regí, & Jansen, 2002). Reactants for HA cements are crystalline calcium phosphates like tetracalcium phosphate (TTCP) or α/β-tricalcium phosphate (α/β-TCP) combined with slightly acidic compounds like dicalcium phosphate anhydride (DCPA) or dicalcium phosphate dehydrate (DCPD). On account of distinctive rates of disintegration of reactants, setting responses will just happen if the dynamic solubilities of all segments are harmonious; subsequently, this is ordinarily balanced by means of the particle size/particular surface range of the reactant particles. The powder stage after blending with a fluid stage like water or a watery arrangement shapes a glue which in light of the solidifying response can frame HA (apatite cements) or DCPD (brushite cements) in the wake of being connected inside of the body (Julien et al., 2007), (Kokubo, 2008), (Van den Vreken et al., 2010), (Ginebra, Traykova & Planell, 2006), (Yang, Troczynski & Liu, 2002). Cements formed at pHs age and the component of contamination. Bacterial reasons for intense and direct Osteomyelitis incorporate group related methicillin-safe Staphylococcus Aureus (MRSA), Kingella Kingae and others. Treatment for osteomyelitis includes the start of intravenous anti-infection agents that enter bone and joint depressions, referral of the patient to an orthopedist or general surgeon and conceivable restorative irresistible illness meeting (King & Kulkarni, 2010). Couple of confusions in reconstructive orthopedics represents a more difficult hindrance to clinical accomplishment than disease, and bacterial osteomyelitis remains an imperative and overwhelming orthopedic and clinical issue. An assortment of prophylactic and helpful systems has been intended to decrease the occurrence and effect of disease. Routine treatment utilizing systemic anti-microbials is costly, inclined to complexities and frequently unsuccessful. In this way, neighborhood treatment is craved to treat or avert osteomyelitis (Lew & Waldvogel, 2004; Ciampolini & Harding, 2000). Gentamicin is an aminoglycosidic antibiotic for bacterial infections caused by staphylococcus which …show more content…
Gentamicin solution with the concentrations of 0.1%, 0.5% and 1.0% were prepared. The model drug solution concentrations were analyzed via UV-Visible Spectrophotometer (Hitachi UV U3010) at 290 nm peak absorbency to obtain the respective absorbance values. The wavelength at 290 nm was determined as the peak absorbency wavelength as maximum absorbency at this particular wavelength was observed. The equation of the linear curve shown in Table 1 and Figure 1 produced with the three points of different concentrations was used to quantify the concentrations of gentamicin in the withdrawn sample solutions. Drug release profiles for the different sets of implants up to 14 days were