 Hello everyone, welcome back to another session in dentistry and more Today we have hypoplasia and fluorosis the two terms which we come across very oftenly in dentistry But when I undergraduate level, we are very confused about these two hypoplasia and fluorosis So when we check a patient's mouth and we see a wide sport or a white mark For a UG student, that's very confusing Whether it be a hypoplasia or a fluorosis So we need to understand the theory the concept the causes the presentation of these two in order to Properly Diagnosed condition that is a white spot or white lines So this session is about understanding hypoplasia and fluorosis its differences and the similarity how it Happens and on which age group it happens. So all those things will be dealt into this session So, let's start hypoplasia and fluorosis. There is one similarity that is both are Hypomineralized structures. Okay, so let's take one example. That is this be a tooth. Okay This is a tooth and we know mineralization cycle Each tooth has different mineralization trees if it is more loss, it starts from birth and If it is a second molar, it starts from around two to three years. I am talking about Mineralization, okay, not eruption mineralization is different eruption is different Mineralization starts at very early time. So once the mineralization complete and total of the root Formation complete then only the tooth erupts into the oral cavity. So I'm talking about mineralization. Okay So when mineralization happens So there is continuous deposition of the calcium The calcium and phosphate crystals into the tooth. Okay, so this is calcium and phosphate Crystals and there are other crystals too, but mostly we say hydroxyapatite crystals calcium and phosphate are the basic Minerals, so this will be deposited in basically an incremental line fashion, but I'm just putting it as a dots. Okay So this is how naturally the mineralization happens But on some conditions, this is not possible the way various reasons for not Properly getting mineralized a tooth is not getting mineralized properly. So we'll come to that later But just understand that the growth is not happening properly. That is Placium the growth or cell multiplication is not happening properly that is Hypoplasia is happening. Okay. So hypoplasia means the mineralization mineralization is Improper that is it is happening less than Normal, okay, so the tooth is not properly mineralized. So there are areas where there is missing of ions that is calcium and Phosphate are missing now it is a hypomineralized tooth or we can say Hypomineralized so these areas will be hypomineralized areas which will be Seen as a more of white dish color. So these areas are hypomineralized color So these areas will be more opaque or more white Compared to the normal enamel because the refractive index of enamel normal enamel Refract index is 1.6. So when it is Properly mineralized tooth. Okay. So when the mineralization is less than normal The refractive index will be Different, okay, so different Refractive index code so it will not be 1.6 Okay, it will not be 1.6. So this is normal enamel. This is hypomineralized enamel So this might be 1.3 Or 1.2 or 1.1 So when we have two different Refractive index on a same object. Okay. So this area, sorry This area the refractive index is 1.6 But this area the refractive index is 1.2 or 1.3. It is different. Anyway, it is not normal So these two will be Seen as different colors. Okay. So this is normal tooth color That is this 1.6 will be Normal enamel a slight yellowish color, but this will be more opaque because of difference in the Refractive index. Okay. So that is why we see white spots or white lines when there is hypominalization because Of the difference in refractive index So that is a concept hypominalized structures. So both hypoplasia and fluorosis are hypominalized structures And they are seen as white lines or opaque areas. Okay So The difference between hypoplasia and fluorosis is a reason. Okay. Why this is happening? hypoplasia and fluorosis why? Fluorosis is happening hypoplasia is happening So that's the difference between these two because hypoplasia is a big thing. Okay. So it's a big thing It has lots of things and one among the hypoplasia is fluorosis because There are many reasons for hypoplasia and one of the reason of hypoplasia is fluorosis Hypoplasia can be caused due to the overconsumption of fluorine That is how fluorosis happens that is the difference between hypoplasia and fluorosis the similarity is both are hypominalized structures but the difference is One is happening due to the fluorine over consumption. Okay So that is a concept behind these two. Now, let's see what are the basic classification So enamel hypoplasia can be basically classified as hereditary and environmental, okay So this is hereditary sorry So i'm new to this Pen tablet. That's why so much of error. So hereditary and Environmental these are the two broad classification of enamel hypoplasia. Okay So hypoplasia is nothing but as I mentioned it's the incomplete or defective formation of the organic enamel matrix So this hereditary has again three classification that is hypoplastic hypocalcified or hypometrative So hypoplastic is nothing but when there is defective formation of organic matrix Organic matrix is not properly formed Whereas hypocalcification there is defective mineralization. Okay Mineralization is different or defective And hypometrative where the defective maturation of Matrix So in both, I mean all three ways the enamel is not properly mineralized one is because of the Matrix of defective formation of matrix next one is a defective mineralization of the matrix and Third one is defective maturation of the matrix. So matrix is not properly mineralized. So that is hereditary. Okay, but the Next category is environmental So environmental we have many reasons they are One is nutritional deficiency Uh, the second one is nutritional deficiency. It could be due to uh rickets rickets That is a vitamin D deficiency. Then xanthematous disease that is uh common, uh, we call rash Then due to the syphilitic hypoplasia syphilis is also a reason for enamel hypoplasia Then hypoplasia due to hypocalcemia that is uh improper calcium concentration in the blood and hypoplasia due to birth injury So these are all environmental reasons for enamel hypoplasia And next one is a turner's hypoplasia or A local injury which affects Only on one tooth just one tooth. Okay. This is due to local injury And the next one is dental Roses, okay Now you must have understood the difference between enamel hypoplasia and prurosis So I already explained to you the mechanism of these two So dental fluorosis is one of the Classification under environmental hypoplasia So This is due to the overdose of fluoride or overconsumption of fluoride mainly during the Calcification period Calcification period of teeth. So that is Basically zero to seven years by seven years up to second molar that is permanent second molar Mineralization or calcification will be complete. So if any person or any child who is consuming fluoride containing water that is more than one ppm usually Fluorosis happens for more than one ppm. Suppose if a child consuming water That is eight-year-old child is consuming water with more than one ppm the Person will not be affected with fluorosis because by seven years The teeth up to second molar that is 28 teeth will be completely mineralized. Okay So if it is milder or severe the effect will be significantly reduced after seven years because Teeth up to second molar will be mineralized by the age of seven years That is how I'm talking about mineralization not eruption So that is the basic difference between dental fluorosis and environment. I mean a hypoplasia hypoplasia very broad thing So it has got hereditary and environmental classification. One of the environmental reason is Fluorine consumption that is known as dental fluorosis. Okay, and also we have one more reason that is tetracycline Overconsumption during the pregnancy also results in enamel hypoplasia. So all these reasons All these reasons Will cause That is hypo means less than normal Less than normal mineralization Okay, this calcium and This calcium and phosphate deposition will be disturbed because of All these reasons. So all these reasons May cause hypoplasia in teeth. Okay So that is the difference between hereditary and environmental hypoplasia So hope you understood the difference between enamel hypoplasia and fluorosis And this concept of refractive Intex and why It is seen as opaque areas or White areas it is because of the difference between refractive index. Okay. Now, let's see Uh the difference between or how do we differentiate a milder form of fluorosis and enamel hypoplasia I'm talking about only milder form of fluorosis. Okay So milder fluorosis And enamel hypoplasia Why I am choosing milder fluorosis because If it is a severe fluorosis, it will be obvious. There will be pitting. There will be brown staining. There will be attrition There will be gross discrepancy the gross form change So milder fluorosis And enamel hypoplasia is very difficult to differentiate. So those criteria. I'm going to explain Enamel hypoplasia. So these criterias were given by Res cells so we can say that is it's res cells criteria of Differentiation, okay So the results criteria the first criteria is First criteria is the area affected. Okay So the area which are the area affected in fluorosis. That is usually it affects on cusp tips Or incisal edge. So when you see A very milder form of fluorosis or enamel hypoplasia That is white areas if you are seen on cusp tips or incisal edge, it will be fluorosis But enamel hypoplasia that is non fluoride type. It will be mostly seen on Smooth surface that is on the center of the tooth and it affects whole crown mostly sometimes whole crown Or as a round shape So this milder fluorosis would be seen on Cusp tip or incisal edge because why because we know mineralization Is directly proportional to Our fluorosis So mineralization starts or calcification starts from the cusp tips or incisal edge So fluorosis also will follow this pattern. That is why fluorosis is seen on Cusp tips or Incisal edge The second one is a shape of nation. So we discussed about area now we have shape. Okay the shape. This is the most striking differentiating feature so in Fluorosis the shape will be Pencil lines Okay, so pencil lines because it follows incremental lines It will be like pencil sketches Because it follows incremental lines Because if this is a tool, okay, you can see like this white lines Whereas in Hypoplasia it will be Like this white area will be seen like this So this is fluorosis and this is Hypoplasia. Okay, so that is the shape Here it will be round or oval shape So area shape after that we have demarcation How it is demarcated from the surrounding normal enamel that is the third one So We just cannot make out the demarcation It shades of imperceptibly into the surrounding normal enamel It just merges Okay, imperceptibly merges to enamel surrounding enamel. You can't make out which Is the border but here in Enamel hypoplasia or normal I mean non non fluoride enamel opacities. You can clearly differentiate Clearly differentiate between The sound enamel if this is a tooth. Okay This is a tooth and This is a tooth So it's not easy It will be some something like so the enamel and the Hypoplastic areas will not be very much Difficult in color or the borders. I mean the boundaries are not very distinct. You can't make out The boundaries of this one Anyway, this is more like a pencil sketches still you can't make out the Boundaries but here It will be a well circumscribed area. You can very easily make out the Boundaries. Okay, so my drawings are not very good So that is how we can make out if it is around oval shape where you can easily make out the boundaries It will be a enamel hypoplasia If it is pencil sketches and you are not able to make out the boundaries That will be fluorosis After that the next differentiating feature is The color. Okay, the next differentiating feature is a color color is more like paper white in Fluorosis, it is more like a creamy yellow color. So that is another striking feature and Next one is a teeth effected teeth effected So this is mostly teeth that Calcify slowly Teeth affected That it's a concept that is a fluorosis affects teeth which calcify slowly like premolars or molars Which takes lots of time to calcify around two to four years. It takes to calcify from the beginning to end It takes two to four years So Since mineralization is a slow process fluorosis is also a slow process So it doesn't occur on teeth which calcify fast like central incisor mostly Lower incisor or upper incisor. So it is very rarely seen on lower incisors Okay So that is our concept it present on teeth which takes lots of time to Calcify or the teeth which calcify very slowly But enamel hypoplacia which can occur on any teeth Because it has lots of reasons it could be a Birth injury it could be a due to fever it could be due to syphilis Or it could be due to nutritional deficiency. So any reason can happen on any tooth. Okay. So that is The teeth affected any tooth is affected Okay So that is a concept Next differentiating feature is a gross hypoplacia, okay gross hypoplacia So that is sixth differentiating feature That is milder fluorosis. It is None there will not be any gross hypoplacia Enamel will be having a glazed appearance because it is a milder form of fluorosis severe form will be having gross hypoplacia Uh but In enamel hypoplacia the glazed surface will not be there. It will be a rough surface So the next one is detection. How do we detect milder fluorosis and enamel hypoplacia under that light? So let this be a tooth surface. Okay This this is a longitudinal section. Okay not cross section longitudinal section. Okay When we checking for fluorosis, we should always use a tangent light. Okay Tangent light the light direction should be at an angle But when we are checking for uh enamel opacities Our light direction should be perpendicular perpendicular and fluorosis tangent. Okay In other words a lesion which is seen on a perpendicular strong light will be a enamel hypoplacia And a white spot which is seen on a tangent strong light will be milder fluorosis. Okay So hope you understood the concept the area affected The cusp tip and incisal agent fluorosis because those are the areas where the first mineralization starts And it is having pencil sketches because it follows the incremental line patterns And the demarcation it is merges with the surrounding enamel. There will not be any clear cut boundaries or demarcation And it is having a paper white area And it scenes on teeth which slowly calcify or longer duration calcification teeth like primolars and molars And those hypoplasia is not there the tooth will be more of like glazed And we should use a tangent light tangent. That is a line of sight should be tangential to the crown Almost opposite in the enamel hypoplasia the round oval shaped White areas which is mostly on the center of the tooth or whole of the crown And you can easily differentiate between the White areas and surrounding normal enamel and the color will be more like creamy yellow And it can affect any tooth and the line of sight or the Light projecting towards the crown should be perpendicular to the tooth surface So that was all about the session. This was more like a concept Clearing session very broad thing. It has got hereditary and environmental reasons and one of the environmental reason is fluorine and due to the overconsumption of fluorine what causes is dental fluorosis. Okay, so if you remember this picture enamel hypoplasia is a big thing and Under the big thing there is a small classification That is Fluorosis, okay And don't forget about the color and its reasons that is a refractive index how mineralization happens How hypoplasia is a thing but hypomenalization and the results criteria of myelofluorosis and enamel hypoplasia So that was all for today. I'll come up with a new topic in oral pathology and industry and more. Thank you