Understanding Glass Ionomer Cement Applications

Hello everyone, we are back with another lecture which is very very important that is the glass inomer cement. Many students find it very difficult to understand but we have tried to make it as easy as possible for you. So this is the fifth part of the lecture series on dental cements. Let's begin with it the glass inomer cement but before we start please subscribe to our channel and also hit on the bell icon so that you don't miss any of our recently updated videos also check our playlist which we have updated on our channel page all lectures are arranged in the playlist in sequence so beginning with today's topic in this lecture of glass ionomer cement we will be studying first the introduction then the application then classification mode of supply of glass ionomer cement the composition how it is manufactured the setting reaction properties manipulation and the modifications of glass ionomer cement and finally we will be solving a small quiz so let's begin the introduction glass ionomer cement is an aesthetic tooth colored restorative material It requires minimal cavity preparation. It adheres chemically with the tooth structure and it has combined properties of the silicate cement and the polycarboxylate cement. The name is glass inomer because the powder is in the form of glass particles and inomer because it forms ionic bond with the teeth. Other names of glass ionomer cement are polyalkinoid cement and aspa or alumino silicate polyacrylic acid. The applications of glass ionomer cement First it is used as a class 5 and class 3 restorative material for anterior teeth. So this is the class 5 and this is the class 3 restorative material in the anterior teeth. Also it can be used as a looting agent. Suppose this is a tooth on which this prosthesis brown colored is the cap or prosthesis which is constructed on this tooth. So, this prosthesis can be luted on this tooth with the help of the glass inomer cement. Thirdly, it can be used as liners and base. When cavity is prepared before filling the final restorative material, a liner or base is placed in the base of the cavity and GIC can be used as this liner or base. Also in core build up. So GIC can be used for making the core of the tooth before the final prosthesis is constructed on it. So it can be used as a core building material. And GIC can also be used as a pit and fissure sealant. So now suppose this is a tooth with deep pits and fissures. So this tooth is more susceptible to caries. These deep pits and fissures are filled with glass inomer cement to prevent this attack of caries in it. Now the classification of glass ionomer cement. Depending upon the use GIC is of three types type 1, type 2 and type 3. Type 1 is the GIC which is used for luting. Type 2 is for restoration and type 3 for liners and bases. Mode of supply. Glass ionomer cement is available as powder and liquid in different bottles or in capsules or as a light cure system. The composition of glass ionomer cement The powder of glass ionomer cement can be described as acid soluble calcium fluoroaluminosilicate glass. It is similar to silicate cement but the alumina silica ratio in the glass ionomer cement is more. So, this increased alumina silica ratio results in increased reactivity of the powder. So, the powder is thus composed of silica 41.9%, alumina 28.6%, aluminium fluoride 1.6%, calcium fluoride 15.7%, sodium fluoride 9.3% and aluminium phosphate 3.8%. The fluoride component act as a ceramic flux in the powder. Landenum, strontium, barium and zinc oxide provides radio opacity to the material. The liquid consists of polyacrylic acid in the form of a copolymer of etrachonic acid, malic acid and tricarbalic acid. This polyacrylic acid copolymer increases the reactivity increases the viscosity and decreases the gelation also the liquid contains tertiary acid with which increases the working time and reduces the setting time water is present in the which acts as a reaction medium and hydrates the reaction products Now, this amount of water is very critical. If this is increased or if it is decreased, it results in reduced physical properties of the cement. Now, there is a concept of water settable cement. Let us see what is this. In water settable glass ionomer cements, the powder is composed of freeze-dried polyacrylic copolymer and glass ionomer powder. While the liquid is simple water or water plus tartaric acid. When this powder is mixed with liquid the polyacrylic acid present in the powder it dissolves with water and forms the liquid. Polyacrylic acid. Now this liquid polyacrylic acid reacts with the powder particles and finally the setting reaction occurs. This water settable cements react very fast. So the setting reaction occurs fast. Now let us study how the glass ionomer cement is manufactured. First all the components of the powder are mixed together and heated to a temperature of 1100 to 1500 degrees Celsius. After heating up to this temperature these particles are then ground to a very fine size of 20 to 50 micrometer. And thus the powder of the GIC is formed. Now let us study the setting reaction of the glass inomer cement. When the liquid is mixed with the powder, the polyacrylic acid present in the liquid, it attacks the glass particles of the powder. As a result of which calcium, aluminium and fluoride ions are leached out from the glass particles into the aqueous media. These released ions form the calcium polysols. Later aluminium polysols cross link with these calcium polysols. Hydration of this, these poly salts occur and which results in the formation of gel matrix. Thus this is the setting reaction of the glass inomer cement. Now let us study the structure of the glass inomer cement. The structure of the glass inomer said cement. Composed of a core of unreacted particles shown by pink circles. These unreacted particles are surrounded by the silica gel shown by Blue circles and these particles are then embedded in a matrix of calcium and aluminium polysols. Now let us see what is post hardening precipitation. The initial setting of the glass inomer cement is due to formation of calcium polysols. As time elapses, The aluminum polysols grow and become the dominant phase in the matrix. If there is contamination of the cement with water prior to setting, there is loss of ions from the cement resulting into dissolution. Now the water content. of the liquid is very important in GIC setting. There is two types of water in the set cement, the loosely bound and the tightly bound water. The loosely bound water, it reduces with time and it is lost by desiccation. While the tightly bound water, it increases with time and it cannot be removed by desiccation. Now the setting time of type 1 GIC is 4 to 5 minutes while type 2 GIC takes 7 minutes to set. Now let us study the properties of the glass inoma cement. First the mechanical properties. The compressive strength is sufficient enough that is 150 mpa while the tensile strength is low that is 6.6 mpa. The noob hardness number is 48 kHn. While the fracture toughness is less than that of composite. The solubility and disintegration. The initial solubility and disintegration is very very high. And it reduces with time. Complete setting requires 24 hours. Solubility is relatively low that is only 0.4%. Now the adhesion of the GIC with the tooth structure occurs with by chemical or the ionic bond. Now this chemical bonding takes place when the reaction occurs between the carboxyl group of poly acids of the cement and the calcium in the apatite of enamel and dentine. These two units they bond with each other to form the chemical bond. Now this chemical bonding is more in enamel than in dentine because the enamel have high inorganic content. Now the biocompatibility type 1 GIC and the water settable cements have acidic pH and they are more hazardous to the pulp while type 2 GIC is quite biocompatible. Also the antikaryogenic property fluoride is released from the glass inomer cement and this fluoride is taken up by the adjacent tooth structure to form a resistant coat which is not penetrated by the acids produced in the mouth. So, the GIC has sufficient anticarionic activities because of the release of these fluoride ions. Now, let us study how the glass inomer cement is manipulated. For a successful glass inomer cement restoration, you should follow four rules. First, the conditioning of the tooth should be proper. Secondly, the manipulation of the material should be proper. Third, the cement should be protected during setting. And finally, proper finishing of the restoration should be done. First, the conditioning of the tooth. GIC bonds chemically with tooth structure so the tooth surface should be clean enough for proper adhesion to occur. When we make a cavity, a microscopic layer called as the smear layer as you can see here in yellow color this is the smear layer. It is left behind after the cavity preparation. So it is necessary to remove this smear layer to allow proper adhesion between the glass inomer cement and the tooth. This removal of the smear layer is achieved by two methods either by the use of polyacrylic acid or by the use of pumice slurry. Now how is this smear layer removed with the help of polyacrylic acid? 10% polyacrylic acid is put on the Cavity prepared for 10 to 15 second and then it is washed with water for 30 seconds. This removes the smear layer. Also, pumice slurry can be used. Pumice is first applied on the prepared tooth surface and then polyacrylic acid is then applied for 5 second. This also removes the smear layer. The second rule is proper manipulation. Accurate powder liquid ratio should be used as indicated by the manufacturer. There are two ways of manipulation by hand or by mechanical manipulation. By hand manipulation, before mixing the bottles containing the powder and the liquid should be tumbled so that all the ingredients are properly mixed. Then cool glass slab or a paper pad is used. Plastic or an agate spatula is used for manipulation of the glass in over cement. Also the powder is added into the liquid in increments. The first increment is added into the liquid to form a milky homogeneous Mix. After this milky homogeneous consistency is obtained, remaining increments are added in folding method. The mixing time of GIC is 45 seconds. Mechanically, pre-proportionated capsules containing powder and liquid can be used and these are then run into a high speed amalgamator. but there are certain advantages and certain disadvantages of mechanical mixing of gic the advantages include controlled powder liquid ratio decrease in the mixing time and easy delivery of the material but the disadvantages are the amount of cement which is mixed is limited that is only which is formed by a capsule and the shades Available in pre-proportioned capsules are very limited. The third rule is the protection of cement during setting. Glass inomer cement is extremely sensitive to loss of water when exposed to air. So, immediately after the placement of this GIC restoration into the cavity, a preformed matrix shown by this red color is placed on this restoration. So, this preformed matrix protect the cement from coming in contact with the environment and this matrix establishes the contour of the restoration. so that minimal finishing is required. Secondly, the cement surface is protected either by application of a varnish or a bonding agent or cocoa butter. Now the last rule is the finishing. Excess material is trimmed off. Cement instruments are preferred because they avoid ditching. And before dismissing the patient, a protective layer of varnish or a cocoa butter is applied. If proper protection is not taken, it results into chalky or crazed surface of the restoration. Now the precautions to be taken while handling GIC restoration. The mix should be glossy. Glossy appearance of the mix indicates the presence of residual polyacids. which provide good adhesion to the tooth. The liquid should be refrigerated because as it contains polyacrylic acid, it becomes viscous with time at room temperature. The air contact with the freshly inserted restoration should be avoided with the presence of a pre-shaped matrix. The glass slab should not be cooled below the dew point because if it is cooled below the dew point there is formation of moisture on it and this moisture it changes the acid base balance reaction. Now there are some modifications of GIC these are produced to improve the physical properties of the GIC. These modifications are the metal modified GIC and the resin modified GIC. Now the metal modified GIC are developed to increase the strength of the GIC, to increase the fracture toughness and to increase the resistance to wear. There are two methods by which the metal modified GIC are produced. First the silver alloy admixed in which the spherical silver alloy particles are mixed with type 2 GIC. And the second method is the formation of cermet in which the silver particles are bonded to glass particles by a process called as sintering. So this results in the formation of cermet, a special cement which is metal modified GIC. Now the properties of this metal modified GIC, the mechanical properties like compressive strength is similar to the conventional GIC that is 150 MPa. The anti-karyogenic activity of the admixed type of metal modified GIC is more because more amount of fluoride is released from this restoration while the cermet has much limited anti-karyogenic activity. These metal modified GIC are grey in color so cannot be used for anterior teeth due to aesthetic issues. the clinical uses of metal modified gic is that it can be used in class 1 cavities and for core buildup in posterior teeth now the resin modified gic is another modification of the gic the conventional gic they they set by the conventional acid-base reaction but these conventional gic are very highly sensitive to moisture So, the resin modified GIC are developed. These GIC contains GIC plus hydroxy ethyl methacrylate. The setting of this resin modified GIC containing hydroxy methyl ethyl methacrylate or the HEMA. The setting of this GIC. is partially by acid-base reaction and partially by photochemical polymerization. The polymerization may either be by light activation or by chemical activation. Other names of this resin modified GIC are light cured GIC, dual cured GIC, tri cured GIC, resin inoma, compoma. or hybrid ionomers so most of the time what students are asked in exam what is compoma so this compoma is nothing but the resin modified gic the composition of this resin modified gic the powder consists of iron leachable glass and the initiation for either chemical or light curing while the liquid consists of water polyacrylic acid polyacrylic acid but plus carboxylic group modified methacrylate and hydroxy ethyl methacrylate the setting reaction the acid and the base reaction occurs when the powder and liquid are added together the polyacrylic acid present in the liquid it reacts with the glass particles water is eliminated during this reaction Then the polymerization continues at a slower rate under the protection of the set resin. Finally, auto curing of the unset resin occurs and thus the total restoration is cured. Now the physical properties due to decrease in the water and carboxylic acid content of the liquid there is difference in the physical properties between the resin modified GIC and the conventional GIC. There is decreased translucency in this resin modified GIC due to a difference in the refractive index. The strength of the resin modified GIC is more. The adhesion to the tooth is similar to that of conventional GIC while adhesion to the composite is more than the conventional GIC. The marginal adaptation of the resin modified GIC. is less due to shrinkage. The material undergoes shrinkage resulting into marginal leakage. The water sensitivity, it is susceptible to dehydration. Now, let us solve a small quiz as we have finished the entire topic on the glass inomer cement. The first question, the initial set of glass inomer cement is due to formation of which polysols? Question number 2. Chemical bonding of GIC with enamel is more or less than that of dentine. Question number 3. Conditioning of tooth done by polyacrylic acid wash or pumice slurry removes which layer from the tooth? And question number 4, GIC in which the silver particles are bonded to the glass powder particles is known as what? Please subscribe to our channel if you have not yet done. And also please comment and let us know your valuable feedback. The next lecture will be on zinc polycarboxylate cement. Till then, happy studying.

Let's begin with it the glass inomer cement but before we start please subscribe to our channel and also hit on the bell icon so that you don't miss any of our recently updated videos also check our playlist which we have updated on our channel page all lectures are arranged in the playlist in sequence so beginning with today's topic in this lecture of glass ionomer cement we will be studying first the introduction then the application then classification mode of supply of glass ionomer cement the composition how it is manufactured the setting reaction properties manipulation and the modifications of glass ionomer cement and finally we will be solving a small quiz so let's begin the introduction glass ionomer cement is an aesthetic tooth colored restorative material It requires minimal cavity preparation. It adheres chemically with the tooth structure and it has combined properties of the silicate cement and the polycarboxylate cement. The name is glass inomer because the powder is in the form of glass particles and inomer because it forms ionic bond with the teeth. Other names of glass ionomer cement are polyalkinoid cement and aspa or alumino silicate polyacrylic acid. The applications of glass ionomer cement First it is used as a class 5 and class 3 restorative material for anterior teeth.

So this is the class 5 and this is the class 3 restorative material in the anterior teeth. Also it can be used as a looting agent. Suppose this is a tooth on which this prosthesis brown colored is the cap or prosthesis which is constructed on this tooth.

So, this prosthesis can be luted on this tooth with the help of the glass inomer cement. Thirdly, it can be used as liners and base. When cavity is prepared before filling the final restorative material, a liner or base is placed in the base of the cavity and GIC can be used as this liner or base. Also in core build up.

So GIC can be used for making the core of the tooth before the final prosthesis is constructed on it. So it can be used as a core building material. And GIC can also be used as a pit and fissure sealant.

So now suppose this is a tooth with deep pits and fissures. So this tooth is more susceptible to caries. These deep pits and fissures are filled with glass inomer cement to prevent this attack of caries in it.

Now the classification of glass ionomer cement. Depending upon the use GIC is of three types type 1, type 2 and type 3. Type 1 is the GIC which is used for luting. Type 2 is for restoration and type 3 for liners and bases. Mode of supply.

Glass ionomer cement is available as powder and liquid in different bottles or in capsules or as a light cure system. The composition of glass ionomer cement The powder of glass ionomer cement can be described as acid soluble calcium fluoroaluminosilicate glass. It is similar to silicate cement but the alumina silica ratio in the glass ionomer cement is more.

So, this increased alumina silica ratio results in increased reactivity of the powder. So, the powder is thus composed of silica 41.9%, alumina 28.6%, aluminium fluoride 1.6%, calcium fluoride 15.7%, sodium fluoride 9.3% and aluminium phosphate 3.8%. The fluoride component act as a ceramic flux in the powder. Landenum, strontium, barium and zinc oxide provides radio opacity to the material. The liquid consists of polyacrylic acid in the form of a copolymer of etrachonic acid, malic acid and tricarbalic acid.

This polyacrylic acid copolymer increases the reactivity increases the viscosity and decreases the gelation also the liquid contains tertiary acid with which increases the working time and reduces the setting time water is present in the which acts as a reaction medium and hydrates the reaction products Now, this amount of water is very critical. If this is increased or if it is decreased, it results in reduced physical properties of the cement. Now, there is a concept of water settable cement.

Let us see what is this. In water settable glass ionomer cements, the powder is composed of freeze-dried polyacrylic copolymer and glass ionomer powder. While the liquid is simple water or water plus tartaric acid. When this powder is mixed with liquid the polyacrylic acid present in the powder it dissolves with water and forms the liquid. Polyacrylic acid.

Now this liquid polyacrylic acid reacts with the powder particles and finally the setting reaction occurs. This water settable cements react very fast. So the setting reaction occurs fast. Now let us study how the glass ionomer cement is manufactured. First all the components of the powder are mixed together and heated to a temperature of 1100 to 1500 degrees Celsius.

After heating up to this temperature these particles are then ground to a very fine size of 20 to 50 micrometer. And thus the powder of the GIC is formed. Now let us study the setting reaction of the glass inomer cement. When the liquid is mixed with the powder, the polyacrylic acid present in the liquid, it attacks the glass particles of the powder. As a result of which calcium, aluminium and fluoride ions are leached out from the glass particles into the aqueous media.

These released ions form the calcium polysols. Later aluminium polysols cross link with these calcium polysols. Hydration of this, these poly salts occur and which results in the formation of gel matrix. Thus this is the setting reaction of the glass inomer cement. Now let us study the structure of the glass inomer cement.

The structure of the glass inomer said cement. Composed of a core of unreacted particles shown by pink circles. These unreacted particles are surrounded by the silica gel shown by Blue circles and these particles are then embedded in a matrix of calcium and aluminium polysols. Now let us see what is post hardening precipitation. The initial setting of the glass inomer cement is due to formation of calcium polysols.

As time elapses, The aluminum polysols grow and become the dominant phase in the matrix. If there is contamination of the cement with water prior to setting, there is loss of ions from the cement resulting into dissolution. Now the water content. of the liquid is very important in GIC setting.

There is two types of water in the set cement, the loosely bound and the tightly bound water. The loosely bound water, it reduces with time and it is lost by desiccation. While the tightly bound water, it increases with time and it cannot be removed by desiccation.

Now the setting time of type 1 GIC is 4 to 5 minutes while type 2 GIC takes 7 minutes to set. Now let us study the properties of the glass inoma cement. First the mechanical properties.

The compressive strength is sufficient enough that is 150 mpa while the tensile strength is low that is 6.6 mpa. The noob hardness number is 48 kHn. While the fracture toughness is less than that of composite.

The solubility and disintegration. The initial solubility and disintegration is very very high. And it reduces with time. Complete setting requires 24 hours. Solubility is relatively low that is only 0.4%.

Now the adhesion of the GIC with the tooth structure occurs with by chemical or the ionic bond. Now this chemical bonding takes place when the reaction occurs between the carboxyl group of poly acids of the cement and the calcium in the apatite of enamel and dentine. These two units they bond with each other to form the chemical bond. Now this chemical bonding is more in enamel than in dentine because the enamel have high inorganic content.

Now the biocompatibility type 1 GIC and the water settable cements have acidic pH and they are more hazardous to the pulp while type 2 GIC is quite biocompatible. Also the antikaryogenic property fluoride is released from the glass inomer cement and this fluoride is taken up by the adjacent tooth structure to form a resistant coat which is not penetrated by the acids produced in the mouth. So, the GIC has sufficient anticarionic activities because of the release of these fluoride ions. Now, let us study how the glass inomer cement is manipulated. For a successful glass inomer cement restoration, you should follow four rules.

First, the conditioning of the tooth should be proper. Secondly, the manipulation of the material should be proper. Third, the cement should be protected during setting. And finally, proper finishing of the restoration should be done.

First, the conditioning of the tooth. GIC bonds chemically with tooth structure so the tooth surface should be clean enough for proper adhesion to occur. When we make a cavity, a microscopic layer called as the smear layer as you can see here in yellow color this is the smear layer.

It is left behind after the cavity preparation. So it is necessary to remove this smear layer to allow proper adhesion between the glass inomer cement and the tooth. This removal of the smear layer is achieved by two methods either by the use of polyacrylic acid or by the use of pumice slurry.

Now how is this smear layer removed with the help of polyacrylic acid? 10% polyacrylic acid is put on the Cavity prepared for 10 to 15 second and then it is washed with water for 30 seconds. This removes the smear layer.

Also, pumice slurry can be used. Pumice is first applied on the prepared tooth surface and then polyacrylic acid is then applied for 5 second. This also removes the smear layer.

The second rule is proper manipulation. Accurate powder liquid ratio should be used as indicated by the manufacturer. There are two ways of manipulation by hand or by mechanical manipulation.

By hand manipulation, before mixing the bottles containing the powder and the liquid should be tumbled so that all the ingredients are properly mixed. Then cool glass slab or a paper pad is used. Plastic or an agate spatula is used for manipulation of the glass in over cement. Also the powder is added into the liquid in increments.

The first increment is added into the liquid to form a milky homogeneous Mix. After this milky homogeneous consistency is obtained, remaining increments are added in folding method. The mixing time of GIC is 45 seconds.

Mechanically, pre-proportionated capsules containing powder and liquid can be used and these are then run into a high speed amalgamator. but there are certain advantages and certain disadvantages of mechanical mixing of gic the advantages include controlled powder liquid ratio decrease in the mixing time and easy delivery of the material but the disadvantages are the amount of cement which is mixed is limited that is only which is formed by a capsule and the shades Available in pre-proportioned capsules are very limited. The third rule is the protection of cement during setting. Glass inomer cement is extremely sensitive to loss of water when exposed to air. So, immediately after the placement of this GIC restoration into the cavity, a preformed matrix shown by this red color is placed on this restoration.

So, this preformed matrix protect the cement from coming in contact with the environment and this matrix establishes the contour of the restoration. so that minimal finishing is required. Secondly, the cement surface is protected either by application of a varnish or a bonding agent or cocoa butter. Now the last rule is the finishing. Excess material is trimmed off.

Cement instruments are preferred because they avoid ditching. And before dismissing the patient, a protective layer of varnish or a cocoa butter is applied. If proper protection is not taken, it results into chalky or crazed surface of the restoration. Now the precautions to be taken while handling GIC restoration. The mix should be glossy.

Glossy appearance of the mix indicates the presence of residual polyacids. which provide good adhesion to the tooth. The liquid should be refrigerated because as it contains polyacrylic acid, it becomes viscous with time at room temperature. The air contact with the freshly inserted restoration should be avoided with the presence of a pre-shaped matrix. The glass slab should not be cooled below the dew point because if it is cooled below the dew point there is formation of moisture on it and this moisture it changes the acid base balance reaction.

Now there are some modifications of GIC these are produced to improve the physical properties of the GIC. These modifications are the metal modified GIC and the resin modified GIC. Now the metal modified GIC are developed to increase the strength of the GIC, to increase the fracture toughness and to increase the resistance to wear. There are two methods by which the metal modified GIC are produced. First the silver alloy admixed in which the spherical silver alloy particles are mixed with type 2 GIC.

And the second method is the formation of cermet in which the silver particles are bonded to glass particles by a process called as sintering. So this results in the formation of cermet, a special cement which is metal modified GIC. Now the properties of this metal modified GIC, the mechanical properties like compressive strength is similar to the conventional GIC that is 150 MPa.

The anti-karyogenic activity of the admixed type of metal modified GIC is more because more amount of fluoride is released from this restoration while the cermet has much limited anti-karyogenic activity. These metal modified GIC are grey in color so cannot be used for anterior teeth due to aesthetic issues. the clinical uses of metal modified gic is that it can be used in class 1 cavities and for core buildup in posterior teeth now the resin modified gic is another modification of the gic the conventional gic they they set by the conventional acid-base reaction but these conventional gic are very highly sensitive to moisture So, the resin modified GIC are developed. These GIC contains GIC plus hydroxy ethyl methacrylate.

The setting of this resin modified GIC containing hydroxy methyl ethyl methacrylate or the HEMA. The setting of this GIC. is partially by acid-base reaction and partially by photochemical polymerization.

The polymerization may either be by light activation or by chemical activation. Other names of this resin modified GIC are light cured GIC, dual cured GIC, tri cured GIC, resin inoma, compoma. or hybrid ionomers so most of the time what students are asked in exam what is compoma so this compoma is nothing but the resin modified gic the composition of this resin modified gic the powder consists of iron leachable glass and the initiation for either chemical or light curing while the liquid consists of water polyacrylic acid polyacrylic acid but plus carboxylic group modified methacrylate and hydroxy ethyl methacrylate the setting reaction the acid and the base reaction occurs when the powder and liquid are added together the polyacrylic acid present in the liquid it reacts with the glass particles water is eliminated during this reaction Then the polymerization continues at a slower rate under the protection of the set resin. Finally, auto curing of the unset resin occurs and thus the total restoration is cured. Now the physical properties due to decrease in the water and carboxylic acid content of the liquid there is difference in the physical properties between the resin modified GIC and the conventional GIC.

There is decreased translucency in this resin modified GIC due to a difference in the refractive index. The strength of the resin modified GIC is more. The adhesion to the tooth is similar to that of conventional GIC while adhesion to the composite is more than the conventional GIC. The marginal adaptation of the resin modified GIC. is less due to shrinkage.

The material undergoes shrinkage resulting into marginal leakage. The water sensitivity, it is susceptible to dehydration. Now, let us solve a small quiz as we have finished the entire topic on the glass inomer cement. The first question, the initial set of glass inomer cement is due to formation of which polysols? Question number 2. Chemical bonding of GIC with enamel is more or less than that of dentine.

Question number 3. Conditioning of tooth done by polyacrylic acid wash or pumice slurry removes which layer from the tooth? And question number 4, GIC in which the silver particles are bonded to the glass powder particles is known as what? Please subscribe to our channel if you have not yet done. And also please comment and let us know your valuable feedback.

The next lecture will be on zinc polycarboxylate cement. Till then, happy studying.

Transcript for:Understanding Glass Ionomer Cement Applications

Transcript for:
Understanding Glass Ionomer Cement Applications