 Welcome back to a new session on dentistry and more. So pits and fissures sealants. So pits and fissures sealants in this topic I will be explaining about the various procedure, various steps involved in pits and fissures sealants, its classifications, its indication and contraindication and why it is important in preventing dental caries. So we have seen this in levels of prevention that is prevention of dental caries and a level one that is primary prevention. So here we seal the pits and fissures so that caries will not occur. So it is just a sealant not a restoration. Restoration is something we do, we restore back to its normal anatomy. Here normal anatomy is not at all affected, only thing we are putting an extra material into the pits and fissures so that it will not turn into a caries area. So always remember pit and fissures sealants are not restorations, it is just a sealant. We do it on a normal tooth to prevent dental caries. Restorations are we are doing to restore something which has lost by dental caries. So these are the pits and fissures as you can see it is just a stained pits and fissures it is not dental caries. So pit is nothing but a point angle, it is a pinpoint depression located at the junction of grooves present over the molar surfaces. A fissure is defined as a deep cleft between adjoining casps of a molar or premolar usually located at the junction of developmental grooves. So this will be a line angle. So pit will be a point angle and fissure will be a line angle. So what are pit and fissure sealants? It is material that is introduced into these pits and fissures of caries susceptible teeth thus forming a micromechanical bonded protective layer which cuts the access of caries producing bacteria from the source of nutrients because always the nutrients such as sucrose will be in these deep pits and fissures. So once we seal off this area this bacteria will not get substrate so only when bacteria act upon the substrate as it will produced and ultimately the caries will happen. So that is the rational behind pit and fissure sealant to cut off the supply of nutrients from bacteria. So why we are applying sealant? Because it is an electromytroscopic picture of molars. I can see the deep pits and fissures where the bristles are not able to enter because of its very narrow size. So food deprise will be entrapped here and it can act as a reservoir or a substrate for the bacteria. So once we seal off this area this food entrapment possibility is zero. So accessibility of the bristles also on the surface. So it can easily clean the surface area. So to make it more cleansable area is the idea of sealant. So as I said the pits and fissures are normal anatomical finding on a dentition. So what we are doing is it can cause dental decay by providing a substrate for the bacteria. So by keeping food retention. So prevent dental caries it should be a more self-cleansable area. So once we seal off this area it will be more self-cleansable or can be easily cleansed by toothbrushes. So dental caries definition we know what it is and it is tetrad not nearly as effective in pits and fissures. It is actually working on the smooth surface that is buccal lingual and other surfaces mesial surfaces not on pits and fissures that is occlusion surfaces. It act on the surface so it can act as a fluoride bomb because it provides a good remuneration on the surface but inside on the deep pits there will be caries progression. So once we start digging the cavity you may end up in a big hole because it may look very smooth very normal from the top layer but once you start creating a cavity for a minor restoration you may end up in a big cavity because the caries progression can't be stopped by fluoride in a deep areas that is deep pits and fissures. So actually deep pits and fissures are the areas where 50 to 85% of the decay is found. So fluoride is effective only on the smooth self cleansing areas buccal lingual and mesial. So most common susceptibility is in this order lower molar, lower second molar, bicar spades, second bicar spades then goes to upper and occlusion mesial buccal lingual are the surface preferences because of its anatomy. Sealants are most effective clinical technique to prevent pit and fissure caries. The cost effectiveness of sealants naturally is based on the sealant retention. So if the sealant is properly placed it is the most effective way to prevent dental caries and it gives a prevention rate of 100% if the sealant is intact. So there was 88% complete sealant retention on self cure sealant on the occlusion surface but only 35% retention on buccal and lingual surfaces. Because occlusion sealants will be retained more because of its anatomical structure. So that's a little detail about its retention. Let's see what are the historical background. So first of all Wilson used zinc phosphate for filling up the caries. Then cleaning and nuts and used muniacal silver nitrate, then extension for prevention introduced by G.V. Black, then prophylactic odendrotomy, hiart fissure eradication by Bodecker, polymer is introduced in 1937, acidation by Binocore, composites introduced during 1916, and this GMA introduced by Bower in 1965, and glass and hammer which was a landmark change in the restorative setting it was introduced in 1972. So we have various classification of pit and fissure sealants based on the polymerization, first, second, third and fourth generation, UV light, self cure, visible light and fluoride releasing. So most commonly we use first generation resin system based on this GMA and urethane acrylate. Most commonly this GMA is used, presence of filler, filled and semi-filled depending upon the color, clear and tinted. So glass and hammer cement is used most commonly, even composites can be used. Glass and hammer cement was introduced by Wilson in 1972. So its better properties are, it chemically bonds with enamel and it unlike amalgam, amalgam is only mechanical bonding, but the chemical bonding is very good, because it has a very chemical reaction happening between the hydroxyapatite crystals. So the retention will be more and release of fluorides which can cause prevention of caries and reminulization. It has stereostatic and antimicrobial activity which is biocompatible and resistance to oral fluid and ease of use. So what are the indications based on the occlusion anatomy, pits and fissures are separated by transverse ridge and a sound pit and fissure may be sealed. There should be a sound pit and fissure, there should not be any caries. But suppose if you have very mild caries, you can do deep, narrow pits and fissures sealing and general caries activity, mild, many occlusion relations, view proximal relations and recently erupted teeth also can be indicated. But mostly pit and fissure sealant done on non-caries relation and mainly on the recently erupted teeth. This all comes under PRR, that is preventive resin restoration. So if we do removal of tooth, it will not come under pit and fissure sealant, it will come under PRR. Because PRR has a name suggest preventive resin restoration, here it is sealant. Contraindications like high caries activity, proximal relations, teeth without caries, free for 4 years or longer. So we commonly do it on the recently erupted teeth. If the tooth is caries free for 4 years in oral cavity, there are very less chances for caries to develop again because it has mineralized completely. Because we know post-sirruptive mineralization will happen within 2-3 years. So after that caries occurrence was very low and patient with rampant caries, intraproximal relations, in such cases we do not do pit and fissure sealants. So these are the basic setup. We need to have a curing light and we are doing type 1 and the basic instruments, HND agent and this sealant material. And this is directly we are putting composite set instead of GAC. We may have powder and liquid. So these are the steps of procedure that is first we need to clean it, then isolate, then itching, then sealant application, curing, inspection and revaluation. So cleaning is as we know we need to clean using a pumice and water slurry and we need to wash, dry and react salmon. We need to properly isolate with the curtain rules. Enamel is sheen based on 37 phosphoric acid for 20 to 30 seconds. After that fully rinse and dry them off, there should be a frosted enamel appearance. It shows that the pores enamel. So after the enamel is porous it will become like this. So there will be irregular surface or more surface energy once the enamel is conditioned. That is H2 with 37% phosphoric acid. So this material sealant material can penetrate and get locked in these depressions. Then we have to apply the sealant material according to manufacturer's directions. Then we have to make for a brush you can use brush it for the curvature of tooth. It can be either light activated or self curing. Always make sure that you avoid air bubbles. Then we need to cure if it is like cure and never to touch this light curing unit tip on the sealant material. Then we need to explore it that is if the material is properly sealed using an explorer and it should not be extend over the marginal reach and any of pollution interferences using articulating paper. It's common how we do a restoration checking and then we need to re-evaluate on a frequent interval. So what are the problems associated that is air bubbles can be entrapped in the material. So always we should make sure that it is not having any air bubbles and porosity is made earlier. Sealant may fall off due to the retention factor. At time we need to reapply the sealant. Cadies TK left under the sealant so there will be secondary cadies. In such cases we should not remove we should not place the sealant and instead we remove the cadies and the filling should be placed. Okay filling and sealant is entirely different. So these are the two things that is perfect isolation and maintenance of a dry field. Two basic things to have a long-lasting bit and fissure sealant and if it is properly placed without any loss of amount of bit and fissure sealant it will provide 100 percentage cadies protection and no other materials such as fluorates or brushing or any other methodology cannot provide 100 percentage of bit and fissure sealants but it should be intact and if it is therefore more than three to four years then there is very very less chances for a cadies to develop in that particular tool. So that's all about bit and fissure sealants remember about the classification and procedures and a little bit about the historical part and a little bit about the bits and fissures. The types I haven't mentioned there are various type like I type Y type J type so most commonly the idea behind this is to cut off the food supply by sealing of the bit and fissures. So I'll come up with PRR in my next session. Thank you.