Dental and medical compositions having a multiple source of metallic ions

Abstract

This disclosure provides bioceramic compositions of multiparticulate crystalline multimetallic silicates having silica double tetrahedra structures, such as Strontium-akermanite (Sr.sub.2MgSi.sub.2O.sub.7), Akermanite (Ca.sub.2MgSi.sub.2O.sub.7), Baghdadite (Ca.sub.3ZrSi.sub.2O.sub.9), Hardystonite (Ca.sub.2ZnSi.sub.2O.sub.7), as sources for controlled release of multiple metallic ions, such as Ca.sup.2+, Mg.sup.2+, Zr.sup.4+, Sr.sup.2+, Zn.sup.2+ for medical and dental use. This disclosure also includes medical and dental uses of the disclosed compositions, for example, in tissue regeneration, including bone tissue.

Claims

1. A bioceramic composition formulated for endodonic application comprising at least one multiparticulate crystalline multimetallic silicate, which is a sorosilicate, at least one liquid carrier and calcium sulfate as a setting agent, wherein upon hydration at a time of the endodontic application, the bioceramic composition flows and the calcium sulfate forms calcium sulfate dihydrate needles and imbricates with sorocilicate crystals, wherein the bioceramic composition hardens.

2. The bioceramic composition according to claim 1, wherein the sorosilicate is selected from the group consisting of Strontium-akermanite (Sr.sub.2MgSi.sub.2O.sub.7), Akermanite (Ca.sub.2MgSi.sub.2O.sub.7), Baghdadite (Ca.sub.3ZrSi.sub.2O.sub.9), Hardystonite (Ca.sub.2ZnSi.sub.2O.sub.7), and a combination thereof.

3. The bioceramic composition according to claim 1, which is in the form of a powder phase and an aqueous liquid carrier.

4. The bioceramic composition according to claim 3, wherein: (a) the powder phase of the composition comprises: optionally, at least one further setting agent selected from the group consisting of calcium acetate, calcium carbonate, calcium oxalate, potassium sulfate, and a combination thereof; and at least one a radiopacifying agent selected from the group consisting of barium sulfate, zirconium oxide, bismuth oxide, tantalum oxide, titanium oxide, and calcium tungstate, and a combination thereof; and (b) the aqueous liquid carrier of the composition comprises: water; at least one accelerator agent from the group consisting of calcium chloride, calcium nitrate, calcium gluconate, calcium lactate, calcium formate, citric acid, potassium sulfate, and a combination thereof; and at least one plasticizer from the group consisting of polyvinylpyrrolidone, polyvinyl alcohol, polyethylene glycol, and a combination thereof.

5. The bioceramic composition according to claim 4, wherein: (a) the powder phase of the composition comprises: from 40 to 70% by weight of at least one sorosilicate; from about 2% to about 10% by weight of at least one setting agent; and from about 20% to about 40% by weight of at least one a radiopacifying agent; and (b) the aqueous liquid carrier of the composition comprises: from about 70% to about 85% by weight of water; from about 5% to about 20% by weight of at least one accelerator agent; and from about 1% to about 5% by weight of at least one plasticizer.

6. The bioceramic composition according to claim 1, which is in the form of non-aqueous paste.

7. The bioceramic composition according to claim 6, wherein the non-aqueous paste form comprises: at least one non-aqueous liquid carrier selected from the group consisting of ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, glycerin, diethyleneglycol dimethyl ether, diethyleneglycol monoethyl ether, butylene glycol, and a combination thereof; at least one a radiopacifying agent selected from the group consisting of barium sulfate, zirconium oxide, bismuth oxide, tantalum oxide, titanium oxide, and calcium tungstate, and a combination thereof; optionally, at least one further setting agent selected from the group consisting of calcium acetate, calcium carbonate, calcium oxalate, potassium sulfate, and a combination thereof; and a rheology control agent comprising at least one micro or nano-sized inorganic particles of silicon oxide.

8. The bioceramic composition according to claim 7, wherein the silicon oxide is selected from the group consisting of silicon oxide, fumed silica, hydrophilic pyrogenic silica, and a combination thereof.

9. The bioceramic composition, according to claim 7, wherein the non-aqueous paste form comprises: from 20 to 40% by weight of at least one sorosilicate; from about 20% to about 40% by weight of at least one non-aqueous liquid carrier; from about 20% to about 40% by weight of at least one a radiopacifying agent; from about 2% to about 10% by weight of a setting agent; and from about 1% to about 5% by weight of a rheology control agent.

10. The bioceramic composition according to claim 1, which contains at least 10% by weight of sorosilicate.

11. The bioceramic composition according to claim 1, which has a particle size distribution with d50 less than 150 microns.

12. The bioceramic composition according to claim 1, which has a particle size distribution essentially with d50 less than 5 microns.

13. A method for inducing tissue regeneration comprising placing the bioceramic composition as defined in claim 1 into the tissue to be repaired.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 is a graph describing the X-ray diffraction patterns of pure akermanite obtained via solid state reaction.

(2) FIG. 2 is a graph describing the granulometric distribution of Baghdatite particles.

(3) FIGS. 3A-C show the setting time assay. FIG. 3A shows a Gilmore-type metric indenter and stainless-steel ring mold. FIG. 3B shows an indentation vertically onto the horizontal surface of the sample. FIG. 3C shows marks of indentations until they are no longer visible.

(4) FIGS. 4A-C show the solubility test. FIG. 4A shows stainless-steel ring mold filled with samples. FIG. 4B shows Petri dishes with cured samples after covered of water for 24 h. FIG. 4C shows samples after drying.

(5) FIGS. 5A-C show the flow test. FIG. 5A shows a glass plate with the sample. FIG. 5B shows two glass plates and an additional mass. FIG. 5C shows a compressed disc of sample.

(6) FIGS. 6A-C show the radiopacity test. FIG. 6A shows a polypropylene ring mold filled with samples and an aluminum step wedge. FIG. 6B shows a polypropylene ring mold filled with samples and an aluminum step wedge. FIG. 6C shows a polypropylene ring mold filled with samples and an aluminum step wedge.

(7) FIGS. 7A-C show the test for determining the film thickness of the compositions of the present disclosure.

(8) FIG. 7A shows two optically flats squares and a loading device. FIG. 7B shows two optically flats squares after loading. FIG. 7C shows a micrometer by determining the thickness.

(9) FIG. 8 shows the cell viability determined using the (MTT) assays. Asterisks represent significant differences compared with the control group (*p<0.05; ** p<0.01, p<0.001), wherein CB5 is Bioceramic composition sealer, CS1 is Market bioceramic sealer, CB6 is Bioceramic composition repair, CR1 is Market bioceramic repair, CS2 is Market bioceramic sealer, CR2 is Market bioceramic repair and CC1 is Market resin sealer. The order in each set of bars is, from left to right: control, CB5, CS1, CB6, CR1, CS2, CR2, and CC1.

(10) FIGS. 9 and 10 shows the migration of human stem cells (hDPSCs Pulp) exposed to extracts of different cements evaluated by in vitro scratch wound-healing assay. In which, CB5 is Bioceramic composition sealer, CS1 is Market bioceramic sealer, CB6 is Bioceramic composition repair, CR1 is Market bioceramic repair CS2 is Market bioceramic sealer, CR2 is Market bioceramic repair and CC1 is Market resin sealer.

(11) FIGS. 11 and 12, respectively, shows cell adhesion in human stem cells (hDPSCs Pulp) exposed to extracts of Bioceramic composition sealer (CB5) and Bioceramic composition repair (CB6) and, then, evaluated by in vitro scratch wound-healing assay.

DETAILED DESCRIPTION

(12) The present inventors have verified that incorporation of multiparticulate crystalline multimetallic silicates into dental or bone cement formulations is possible, but also that the dissolution rate and the pH around the application area are physiologically acceptable. They also verified that certain multiple silicates, when in the multiparticulate form, have structuring characteristics in the cavity or place of application.

(13) This disclosure provides bioceramic compositions, in powder/liquid or paste forms, comprising multiparticulate crystalline multimetallic silicates, as a source of metallic ions, such as Ca.sup.2+, Mg.sup.2+, Zr.sup.4+, Sr.sup.2+, Zn.sup.2+, for promoting bioactivity. The disclosed compositions can be used in medical and dental applications, for example, for use in tissue regeneration, including bone tissue. However, it will be appreciated that the compositions are not limited to these particular applications.

(14) Crystalline multimetallic silicates are silicate materials having crystalline structure of two tetrahedron of the anionic group (Si.sub.2O.sub.7).sup.6 linked by an oxygen ion and therefore with a negative charge of six (6). This crystalline structure has an hourglass shape with the oxygen ion in the center being shared by the double tetrahedron, in a silicon/oxygen ratio of 2/7 and the double tetrahedron are in turn linked together by the different metal cations present in their formulation. Compounds having said structure are named sorosilicates.

(15) The structure of the sorosilicates exhibit differences in crystalline structure and chemical composition when compared to nesosilicates, such as, tricalcium-silicate (Ca.sub.3SiO.sub.5) and dicalcium-silicate (Ca.sub.2SiO.sub.4). The nesosilicates have a crystalline structure of isolated silica tetrahedron (SiO.sub.4).sup.4 bound by a single metal ion, Ca.sup.2+. The crystalline structure of the sorosilicates consists of two silica tetrahedra connected by a shared oxygen atom (Si.sub.2O.sub.7).sup.6 through a covalent bond (SiO), these double tetrahedra of silica being bound by two metallic ions selected from Ca.sup.2+, Mg.sup.2+, Zr.sup.4+, Zn.sup.2+, and Sr.sup.2+.

(16) Due to their crystalline structure and chemical formulation, sorosilicates have unique characteristics in terms of bioactivity. Their double tetrahedron of silica gives them a low solubility that when releasing their multiple metallic ions in a constant and balanced manner it is able to promote the osteogenic differentiation of the osteoblasts, the cells of the dental pulp, the stromal cells of the bone marrow; stem cells derived from adipose tissue, fibroblasts and periodontal ligament cells (Hoppe A, Gldal N S, Boccaccini A R (2011), A review of the biological response to ionic dissolution products from bioactive glasses and glass-ceramics. Biomaterials 32, 2757-2774); and are also able to accelerate bone regeneration in vivo.

(17) In addition, sorosilicates have a relatively wide range of chemical compositions and their physical, chemical and biological properties can be optimized to meet tissue regeneration requirements according to the employed metal ion type.

(18) Examples of suitable crystalline multimetallic silicates are the compounds of the sorosilicate group, such as Strontium-akermanite (Sr.sub.2MgSi.sub.2O.sub.7), Akermanite (Ca.sub.2MgSi.sub.2O.sub.7), Baghdadite (Ca.sub.3ZrSi.sub.2O.sub.9) and Hardystonite (Ca.sub.2ZnSi.sub.2O.sub.7).

(19) The structuring mechanism of the bioceramic compositions described herein is distinct from compositions based on calcium silicates, which when hydrated form a CSH phase. When the bioceramic compositions described herein are in contact with water, the calcium sulfate hemihydrate (CaSO.sub.4.H.sub.2O) present in their composition is dissolved into dihydrate (CaSO.sub.4.2H.sub.2O), which is poorly soluble causing a saturation in the physiological environment and, consequently, precipitation in needles-shaped crystals. The imbrication of these calcium sulfate dihydrate needles (CaSO.sub.4.2H.sub.2O) with hydrated sorosilicate crystals (M.sub.1.M.sub.2.Si.sub.2O.sub.7.H.sub.2O) imparts cohesion and mechanical strength to the bioceramic compositions described herein, at the same time as the interaction between growing crystals causes a small desirable expansion, the mechanism of the reaction can be demonstrated in the following equation, in which M.sub.1 and M.sub.2 are independently selected from Ca.sup.2+, Mg.sup.2+, Zr.sup.4+, Sr.sup.2+, and Zn.sup.2+:
M.sub.1M.sub.2Si.sub.2O.sub.7+(CaSO.sub.4.H.sub.2O)+H.sub.2O.fwdarw.M.sub.1.M.sub.2.Si.sub.2O.sub.7.H.sub.2O+CaSO.sub.4.2H.sub.2O+heat

(20) The bioceramic compositions disclosed herein, when contacted with the body fluid, release the metal ions (M.sup.+=Ca.sup.2+, Mg.sup.2+, Zr.sup.4+, Sr.sup.2+, or Zn.sup.2+) which are exchanged for H.sup.+ by the breakage of the silicon-oxygen-metal (SiO-M.sup.+) bond. Then, these H.sup.+ ions bind to the silicate (Si.sub.2O.sub.7).sup.6 to form a silica-rich amorphous colloidal layer (SiOH) known as silanol, the reaction is demonstrated in the equation below:
SiO-M.sup.++H.sup.++OH.sup..fwdarw.SiOH+M.sup.+(aq)+OH.sup.

(21) After formation of the silanol groups, the pH of the solution increases at the surface of the material causing condensation and re-polymerization thereof to form a layer of silica gel on the surface of the bioceramic composition, according to the reaction described in following equation:
SiOH+SiOH.fwdarw.SiOSi+H.sub.2O

(22) As a result of these initial steps, the surface of the bioceramic compositions disclosed herein exhibit an alkaline pH and an adequate concentration of multiple metal ions, in which this constant release of the metal ions in a chemically balanced environment allows for enzymatic changes that will influence and stimulate cellular differentiation and, thus, tissue formation promoting repair and regeneration of the affected area, more specifically, repair and regeneration of tissue-bone and dentin-pulp complexes.

(23) In an embodiment, the bioceramic compositions are available in the form of powder phase and an aqueous liquid carrier.

(24) In an embodiment, the bioceramic compositions are available in the form of non-aqueous pastes.

(25) In a further aspect, the bioceramic compositions show radiopacity, that is, the ability of the material to reflect the X-rays used in a radiological examination. This feature is very important for material used within the dental and medical field. To impart this feature to the material, various radiopacifying agents can be used for both, the powder and paste forms, for example derivatives of barium, zirconium, bismuth, tantalum, titanium, tungsten, among others, but not limited thereto. Examples of suitable radiopacifying agents are barium sulfate, zirconium oxide, bismuth oxide, tantalum oxide, titanium oxide, and calcium tungstate. In an embodiment, the radio-opacifying agent is calcium tungstate.

(26) In a further aspect, the bioceramic compositions comprise a setting agent. To impart this hardening to the composition, various setting agents can be used for both, powder and paste forms, such as calcium acetate, calcium sulfate, calcium carbonate, calcium oxalate, potassium sulfate, or a combination thereof. In an embodiment, suitable setting agents are calcium sulfate and potassium sulfate.

(27) In some embodiments, water is used as a carrier of the liquid phase of the composition.

(28) In a further aspect, the bioceramic compositions comprise an accelerator agent. To impart this feature to the material, various accelerator agents may be used in the aqueous liquid carrier comprising at least one selected from calcium chloride, calcium nitrate, calcium formate, calcium gluconate, calcium lactate, citric acid, or a combination thereof.

(29) A suitable plasticizer of the composition may be used in the liquid phase, such as, for example, at least one of materials derived from polyvinyl

(30) pyrrolidone, polyvinyl alcohol, polyethylene glycol, or combinations thereof.

(31) Suitable non-aqueous liquid carriers of the compositions in the form of a non-aqueous paste can be members of a glycol group, such as ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, glycerin, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether, butylene glycol, or combinations thereof.

(32) The bioceramic compositions disclosed herein can also comprise a rheology control agent incorporated into the paste for rheology adjustment. Suitable rheology control agents can be selected from micro and nano-sized inorganic particles of different silicon oxides group, such as hydrophilic pyrogenic silica, silicon oxide, fumed silica or combinations thereof.

(33) In an embodiment, the bioceramic compositions have a powder phase and an aqueous liquid carrier, wherein the solid phase comprises from 20 to 90% by weight of at least one multiparticulate crystalline multimetallic silicate, from 10 to 50% by weight of a radiopacifying agent, from 1 to 20% by weight of a setting agent, and wherein the aqueous liquid carrier comprises from 50 to 98% by weight of a vehicle, from 2 to 30% by weight of an accelerator agent and from 0.5 to 10% by weight of a plasticizer. In an embodiment, the solid phase comprises from 40 to 70% by weight of at least one multiparticulate crystalline multimetallic silicate, from 20 to 40% by weight of a radiopacifying agent, from 2 to 10% by weight of a setting agent, and the aqueous liquid carrier comprises from 70 to 85% by weight of a vehicle, from 5 to 20% by weight of an accelerator agent, from 1 to 5% by weight of a plasticizer.

(34) In an embodiment, the bioceramic compositions in the non-aqueous paste form comprise from 10 to 60% by weight of at least one multiparticulate crystalline multimetallic silicate, from 30 to 70% by weight of a radiopacifying agent, from 1 to 20% by weight of a setting agent, from 0.5 to 10% by weight of a rheology control agent and from 20 to 60% by weight of a non-aqueous liquid carrier. In an embodiment, the bioceramic compositions comprise from 20 to 40% by weight of at least one multiparticulate crystalline multimetallic silicate, from 20 to 40% by weight of a radiopacifying agent, from 2 to 10% by weight of a setting agent 1 to 5% by weight of a rheology control agent and from 20 to 40% by weight of a non-aqueous liquid carrier.

(35) This disclosure also includes the use of the disclosed bioceramic compositions for dental and medical applications, for example, for use in tissue regeneration, including bone tissue.

EXAMPLES

Example 1: Preparation of the Bioceramic Compositions in the Powder/Liquid Form

(36) In the Bioceramic compositions 1 and 2 as described in Table 1, the solid components were firstly prepared in powder form using a planetary mixer in the following sequence: sorosilicate, radiopacifying agent and setting agent at speed below 400 rpm, about 30 minutes until complete homogenization. The aqueous liquid carrier was prepared using a mechanical stirrer and the components were added in the following sequence: water, accelerator agent and plasticizer at speed below 800 rpm, about 60 minutes until complete homogenization.

(37) TABLE-US-00001 TABLE 1 Bioceramic compositions Powder phase Aqueous liquid carrier Sample Sorosilicate Radiopacifier Setting agent Vehicle Accelerator agent Plasticizer CB 1 Akermanite Calcium Calcium sulfate/ Water Calcium chloride Polyvinyl 68% tungstate potassium sulfate 75% 20% alcohol 5% 22% 10% CB 2 Baghdadite Calcium Calcium sulfate/ Water Calcium chloride Polyvinyl 68% tungstate potassium sulfate 75% 20% alcohol 5% 22% 10%

Example 2: Preparation of the Bioceramic Compositions in the Non-Aqueous Paste Form

(38) The Bioceramic compositions in Table 2, below, were prepared by mixing the liquid component (carrier) with the solid components in a mechanical stirrer, in the following sequence: sorosilicate, radiopacifier, rheology control agent and setting agent with speed below 500 rpm, approximately 45 minutes until complete homogenization.

(39) TABLE-US-00002 TABLE 2 Bioceramic compositions Non-aqueous Paste Rheology Liquid control Sample Sorosilicate Radiopacifier carrier agent Setting agent CB 3 Hardystonite Calcium Polyethylene Silicon Calcium 26% tungstate glycol oxide sulfate/potassium 37% 25% 2% sulfate 10% CB 4 Strontium- Calcium Polyethylene Silicon Calcium akermanite tungstate glycol oxide sulfate/potassium 35% 35% 25% 2% sulfate 3% CB 5 Akermanite Zirconium Polyethylene Silicon Calcium 22% oxide glycol oxide sulfate/potassium 35% 33% 2% sulfate 8% CB 6 Akermanite Zirconium Polyethylene Silicon Calcium 30% oxide glycol oxide sulfate/potassium 28% 29% 4% sulfate 9%

Example 3: Physico-Chemical Characterization of Bioceramic Compositions

(40) Sorosilicate component was characterized by X-ray diffraction in order to identify the constituent phases and by laser diffraction to identify their particle size distribution. FIG. 1 presents the X-ray diffraction pattern showing the characteristic peaks identification of the Akermanite sorosilicate with the presence of Ca.sub.2MgSi.sub.2O.sub.7 crystalline phase. FIG. 2 presents the particle size distribution of the Akermanite phase with d50 less than 1.58 m.

(41) The physical-chemical characterization of bioceramic compositions 1 to 6 was performed according to ISO 6876: 2012DentistryRoot canal sealing materials. For the determination of the setting time, 3 specimens of each composition described in Examples 1 and 2 were produced and kept in a climatic chamber at 371 C. and 955%. Ten minutes after the samples preparation, they were subjected to marking with the aid of a Gilmore needle. The times elapsed from the beginning of the production of the samples to the moment when it was no longer possible to visualize any type of needle marking on the surface of the material were recorded (FIGS. 3A-C). The result of the setting time is shown in Table 3.

(42) For the solubility tests two specimens with 20 mm diameter and 1.5 mm height of each composition described in Examples 01 and 02 were prepared. These samples were kept in distilled water in Petri dishes at 37 C. for 24 hours. After this period, the water accompanied by the samples was filtered on filter paper and collected on a second Petri dish (initial mass). This plate was kept in a heating muffle at 100 C. and the water was completely evaporated. Solubility was determined by the difference between the initial mass and the final mass of the Petri dish (FIGS. 4A-C) and the result is presented in Table 3.

(43) The flow was determined using three samples of each of the bioceramic compositions from 1 to 4 described on Examples 1 and 2. Two glass plates having dimensions of 40 mm (height)40 mm (width)5 mm (thickness) were used. With the aid of a graduated syringe, 0.0500.005 ml of each sample was placed on one of the glass plates. After 180 seconds from the start of the sample preparation, the other glass plate, and a weight of 100 g, were placed over the material. Ten minutes after the start of the test, the weight was removed, and the largest and smallest diameters of the disk formed by the bioceramic compositions were measured (FIGS. 5A-C). The result of the flow is shown in Table 3.

(44) For determining the radiopacity of the bioceramic compositions 1 to 6 of Examples 1 and 2, specimens with 10 mm diameter and 1.000.01 mm height were produced. The samples were positioned close to an aluminum scale (1-7 mm Al) for comparison of the optical density. A digital sensor along with an X-ray emitter were used to capture the images (FIGS. 6A-C). The result of the radiopacity is shown in Table 3.

(45) The film thickness of the bioceramic compositions 1 to 4 of Examples 1 and 2 was determined by applying the material between two flat square glass plates having a thickness of 5 mm and a contact surface of approximately 200 mm2. After 3 minutes from the application of the material, a load of 150N was applied over the set and the film thickness was measured with a micrometer (FIGS. 7A-C). This assay was repeated three times for each of the compositions and the film thickness result is shown in Table 3.

(46) TABLE-US-00003 TABLE 3 Physical properties of the bioceramic compositions 1 to 6. Setting Film time Solubility Radiopacity thickness (min) (%) Flow (mm) (mm Al) (m) CB 1 60 17 1.52 0.02 18.52 2.95 6 27 3 CB 2 70 15 1.64 0.06 19.12 1.17 6 22 3 CB 3 180 20 2.75 0.02 23.05 2.15 6 14 1 CB 4 160 17 2.64 0.03 22.73 1.75 6 11 2 CB 5 200 35 1.29 0.37 22.32 1.94 6 37 8 CB 6 90 29 1.02 0.15 Not 6 Not applicable applicable

(47) The ions release from the bioceramic compositions 1 to 6 was determined by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). Samples were prepared according to the procedure described in Examples 1 and 2. Disks of the prepared samples were kept in 30 mL of a simulated body fluid solution (SBF) pH 7.25 at 37 C. and evaluated in 1, 3, 5, 7, 10 and 20 days. The concentrations of ions from the SBF were similar to those found in human blood plasma according to Kokubo (Kokubo T (1990) Surface chemistry of bioactive glass-ceramics Journal of Non-Crystalline Solids 120, 138-151). Aliquots of the solution were collected at 1, 3, 5, 10 and 20 days, and the concentrations of ions (Ca.sup.2+, Mg.sup.2+, Zr.sup.4+, Zn.sup.2+, Si.sup.4+) in the solutions were determined by ICP-AES as shown in Table 4. The pH variations of the resulting solutions were also determined with a digital pH meter. The results are presented in Table 4.

(48) TABLE-US-00004 TABLE 4 Concentration of the ions released from the bioceramic compositions 1 to 6. Ionic concentration (ppm) pH Days CB 1 CB 2 CB 3 CB 4 CB 5 CB6 CB 1 CB 2 CB 3 CB 4 CB 5 CB6 1 Ca(180) Ca(120) Ca(110) Sr(150) Ca(132) Ca(174) 7.7 8.2 7.5 9.2 10.2 10.4 Mg(50) Zr(32) Zn(20) Mg(80) Mg(56) Mg(92) Si(52) Si(45) Si(40) Si(35) Si(23) Si(63) 3 Ca(215) Ca(132) Ca(109) Sr(180) Ca(145) Ca(176) 8.2 9.0 8.0 9.4 11.2 11.6 Mg(51) Zr(36) Zn(25) Mg(82) Mg(63) Mg(89) Si(56) Si(47) Si(42) Si(32) Si(35) Si(58) 5 Ca(220) Ca(125) Ca(100) Sr(150) Ca(151) Ca(172) 8.0 9.5 7.6 9.2 10.2 10.9 Mg(50) Zr(30) Zn(27) Mg(82) Mg(52) Mg(87) Si(54) Si(42) Si(37) Si(32) Si(35) Si(54) 10 Ca(200) Ca(90) Ca(95) Sr(145) Ca(140) Ca(168) 8.5 8.7 7.8 9.0 10.6 10.8 Mg(47) Zr(28) Zn(21) Mg(80) Mg(50) Mg(86) Si(43) Si(39) Si(40) Si(38) Si(26) Si(51) 20 Ca(172) Ca(95) Ca(92) Sr(110) Ca(137) Ca(165) 8.7 8.2 7.4 9.5 10.4 10.9 Mg(42) Zr(27) Zn(17) Mg(72) Mg(43) Mg(82) Si(38) Si(32) Si(39) Si(27) Si(19) Si(43)

Example 4: Assay for Determining Hydroxyapatite Formation

(49) To evaluate the ability of hydroxyapatite formation by the bioceramic compositions, samples with a mean particle size of 1.5 m were stored in a solution of simulated body fluid (SBF) pH 7.25 at 37 C. and evaluated at 1, 3, 5, 7, 10 and 20 days using the mass/volume ratio of 1.5 mg/mL. After 20 days the disks were washed with water and dried at 60 C. The amount of hydroxyapatite was determined by the phosphorus (P) content in the samples by dispersive energy X-ray fluorescence spectrometry. The mass percentage found is related to hydroxyapatite formation. The results are presented in Table 5.

(50) TABLE-US-00005 TABLE 5 Percentages by weight of phosphorus obtained by area mapping by X-ray fluorescence of the bioceramic compositions 1 to 6. Days Element P (%) Samples 1 2 3 5 10 20 CB 1 0.081 0.075 0.080 0.131 0.203 0.213 CB 2 0.062 0.071 0.075 0.082 0.101 0.123 CB 3 0.055 0.051 0.063 0.079 0.088 0.095 CB 4 0.079 0.085 0.094 0.099 0.125 0.182 CB 5 0.082 0.090 0.105 0.122 0.143 0.196 CB 6 0.095 0.105 0.132 0.160 0.184 0.208

(51) While some embodiments are shown and described herein, one skilled in the art will appreciate that modifications and variations are possible in light of the above teachings.

Example 6: Cell Viability in Human Stem Cells (hDPSCs Pulp)

(52) The number of viable cells or cells viability after exposure to bioceramic compositions was determined using the chromogenic indicator 3-(4,5-dimethyl-thiazol)-2,5-diphenyl-tetrazolium bromide (MTT) assays for 72 hours.

(53) The cell viability observed after incubation found was compared with control (without cements) and with a Market resin sealer (CC1), in which control showed the highest cell viability while CC1 showed the lowest, i.e., showing an unsatisfactory result for CC1.

(54) It was also possible to see differences between Bioceramic composition sealer (CB5), Market bioceramic sealer (CS1), Bioceramic composition repair (CB6), Market bioceramic repair (CR1), Market bioceramic sealer (CS2) and Market bioceramic repair (CR2). The results are presented in FIG. 8.

Example 7: Cell Migration in Human Stem Cells (hDPSCs Pulp)

(55) The gradual decrease in cell migration over time indicates faster healing of the damaged region and a positive response in terms of cure rate. The migration of human stem cells (hDPSCs Pulp) in the presence of bioceramic compositions, so as in the presence of a control and of a Market resin sealer, was evaluated by in vitro scratch wound-healing assay.

(56) It was also possible to see differences between Bioceramic composition sealer (CB5), Market bioceramic sealer (CS1), Bioceramic composition repair (CB6), Market bioceramic repair (CR1), Market bioceramic sealer (CS2) and Market bioceramic repair (CR2), wherein the Bioceramic composition sealer (CB5) and the Bioceramic composition repair (CB6) showed lower cell migration when compared to the marked bioceramic sealer (CS1) and repair (CR2). The results are presented in FIGS. 9 and 10.

Example 8: Cell Adhesion in Human Stem Cells (hDPSCs Pulp)

(57) Cell adhesion was also evaluated by means of in vitro scratch wound-healing assay. HDPSCs cells were analyzed by difference in staining with phalloidin (cell nucleus) and DAPI to visualize actin cytoskeleton.

(58) Cell adhesion results showed excellent interaction and adhesion between neighboring cells in the presence of bioceramic composition. The Bioceramic composition sealer (CB5) and Bioceramic composition repair (CB6), showed a gradual increase in growth over time, an extended morphology and a high content of F-Actin (cell microfilamen), reaching confluence after 72 hours of culture.

(59) The analysis of cell proliferation (via cell viability study), apoptosis, cell adhesion and morphology (via cell adhesion study) and migration (via cell migration study) showed very positive results, indicating that the proposed bioceramic composition induces the odonto/osteogenic mineralization and differentiation process in the presence of tooth-specific human stem cells (hDPSCs pulp). While a market resin sealer was also used in the comparative studies, however, all results were not satisfactory for this product.