[Music] welcome back a4da students today theresa is going to go ahead and explain how to assemble a toffeemeyer in a matrix band and go ahead and place it on a prep tooth hi so first we're going to go over our ppe which is our gloves jackets masks glasses or goggles so that's a prep tooth this is a topple meyer this is a matrix band these are wedges and these are cotton pliers cotton rolls and two by twos what is going on here is the doctor has prepared the tooth for a do on number 13. what this does is helps the doctor repair that wall if the mesial or distal is missing from the tooth the doctor can use this little band to go in there and help seal that wall back in to hold the tooth and around the hole around the tooth and to make sure that the tooth doesn't get stuck to the other tooth and that the walls can be replaced so we're going to hold the matrix band up we're going to do it as a smile up we're going to fold it in gently we don't want to make a crease in it so this side is smaller than this side so two different sides larger and smaller the smaller side is going to come towards us i'm going to change hand this little u should always face you so this is going to come right in into the little slots and comes through i'm going to put it to the left side and then just tighten this little lower device this little knuckle tightens it this bigger one makes it bigger and smaller for molars and premolars this is only used for molars and premolars so now as i face it towards you you can see that the smaller side is facing you this will face the tooth the gum line so i'll show you so this will go on to the gum line the larger side goes up the smaller side goes down because the smaller side is towards the gums then you can take this and tighten it the larger knob and make it smaller around this tooth just going to tighten it there we go now i'm going to take one of these little wedges and turn it up like you see that kind of so the points going up and our prep is on our distal so i'm going to put this in the distal and then turn my pliers around and push in doesn't hurt them they're numb remember that the u of the matrix band or the top of my is always going to face you and then this is always going to go out of the mouth so when they're closed you'll see and that's a matrix pin to take it off we would just grab pull this out and then loosen this little knob which is what's the one that tightens it hold our finger right here so nothing gets dislodged where we don't want it and then we would gently just pull this off and take our pliers and take it out and that's your matrix man