 Hello everyone, welcome back to another session in dentistry and more. Today we have a small topic from prosaeronics that is disinfection of impression. In prosaeronics we have many types of impression, alginate impression, the impression compound, the one we use for secondary impression that is zinc oxide, original impression. So many impressions are there. So how do we disinfect it? So that is what we are going to learn in today's session. Commonly we have two methods that is spraying and immersing. So in both the methods we use certain disinfectant. So let us see one by one on what impression, what disinfectant we used. So we will start with our alginate impression. So alginate impression disinfection can be done with 0.5% sodium hypochlorite or we can use adipose. So adipose immersion disinfection for prolonged periods might cause distortion due to the process of imbibition process. But only if it is kept for prolonged period, imbibition. Bibition is just like the impression will absorb water and there will be distortion. That is about alginate impression. Whereas for agar hydrocolloid we use the same reagent that is sodium hypochlorite or adipose. In sodium hypochlorite we need to use an adiabation of 1 is to 10 and if it is adipose we need to use it in an adiabation of 1 is to 2 and the recommended immersion time is 10 minutes. So in zinc oxide usional that is our secondary impression for complete engine. We can use either 2% glutaraldehyde adipose or chlorine compounds. But in case of hypochlorite if it is kept around 16 hours there will be distortion. So that is very prolonged period 16 hours. In case of agar hydrocolloid it is just 10 minutes. So more than 10 minutes there will be distortion but this is it can be kept up to 16 hours. More than it there will be distortion if it is kept in sodium hypochlorite. Whereas the impression compound so that we can use the same method for agar hydrocolloid that is 1 is to 10 ratio of sodium hypochlorite or using adipose. So that is commonly kept for 10 minutes. So the impression compound and agar hydrocolloid are having the same method of disinfection. Next we have the elastomeric materials such as the polysulfide and adhesion silicon where we can use glutaraldehyde, hydrophose or 0.5% sodium hypochlorite. This is the polyether so we can just spread adipose or 0.5% sodium hypochlorite but like any other material prolonged immersion cause distortion. But we just cannot use this 2% glutaraldehyde because there can be dimensional change for polyether material. Next we have wax bites or wax rims. So these wax rims and wax bites should be disinfected by the spray wipe using an adipose. So this rinsing and spraying may be more appropriate for the wax bites. If we suspect tuberculosis problem for the patient in such case we need to immerse the wax bites or wax rims for more period that is a longer period. So after the second spray they can be enclosed in a sealed plaster bag for the recommended time. So these items probably should be rinsed again after disinfection to remove any residual disinfectant. The next one we have is biterage station. So biterage station is made of various materials or compounds can be handled in the same manner as impressions of the same material. So we have lots of impression material here. So which material we are using for biterage station that can be followed. So the material for that particular material can be followed. So these registrations disinfected with the technique of rinsing or spraying. So after disinfection the registration should be rinsed again to remove any residual disinfectant. Next we have disinfection of cast. So AD recommended that the stone cast be disinfected by the spraying method until wet or immersion in 1-10% sodium hypochlorite or adipose. So cast to be disinfected should be fully set that is stored at least for 24 hours. So we can use microwave irradiation for 5 minutes that is 900 watt. Then we have the acrylic trace that is acrylic resin impression trace the same method we can use 1-10% sodium hypochlorite or 1-2 adipose. Then we have the final one that is the processes or appliances there we can use the same one that is 1-10% hypochlorite and 1-2 adipose for 10 minutes. So that was all about disinfection of impression. This is quite enough to write for a short essay or short note. We have listed all the impressions. So we started with alginate it is by 0.5% sodium hypochlorite and adipose. Then we have agar hydrochlorite that is 1-10% sodium hypochlorite and 1-2 adipose maximum time is 10 minutes. Then our zinc oxide usional that can be done by 2% glutaraldehyde. Then the chlorine maximum time is 16 hours after that there will be distortion. Then the impression compound that is we follow the same method for agar hydrochlorite that is 1-10% sodium hypochlorite or adipose. Then we have elastomeric impression such as polysulfide or addition silicon adipose or 0.5% sodium hypochlorite is used glutaraldehyde is not used because of dimensional change. Poly ether also we can follow the same method wax bites or wax rins we commonly use adipose even for bite registration but bite registration we first need to know which impression method or compound is used. So we can follow that method. Then we have the cast acrylic trace and processes or dental appliances where commonly we used 1-10% sodium hypochlorite and adipose. 5 minutes microwave radiation for about 900 watt. So that was all about disinfection of impression that was a simple topic in prosthodontics but it is a topic which comes frequently for exam. So I will come up with a new topic in prosthodontics thank you.