TECHNICAL INSTRUCTIONS FOR TILITE ALLOYS

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1 WAXING COPINGS Wax-up very thin, from 0.2mm, one dip in the wax pot is sufficient. If the teeth are broken down build them up, to about 4 mm under occlusion. WAXING PONTICS Wax-up pontics on the small side, leave about 4 mm for the porcelain all the way around. Due to the high tensile strength of Tillte, you can have thin connections to the abutments. SPRUING SINGLE COPINGS The runner bar spruing technique is recommended. Cut off a 4 mm length of a 3,5mm Ø sprue, roll up one end between your fingers to get a tapering point, now connect it to the coping. For large posterior copings or for very thick copings use a 4mm Ø. wax and two sprues if necessary. Very Important When connecting the copings to the bar it is important to angle the open end of the copings, so that when the investment is poured into the ring it runs down only one side of the coping opening, and does not trap the air at the bottom of coping. Connect all copings to the bar of 5 mm Ø of any shape, straight or round, depending on the no. of copings you have. (You can have up to 50 copings in one ring). Now attach a main sprue of 5mm Ø to the bottom of the runner bar, and the whole thing to the sprue former. For up to 10 copings a single main sprue is sufficient, for copings use two main sprues, and for more than 20 use 3 main sprues. SPRUING BRIDGES Up to 3 unit bridge, sprue the same way, but use 4mm Ø sprue on the Pontic. For more than 3 units please use our technique for casting, long span bridges, with the recommended investment (see attached tutorial). CLEANING THE COPINGS Clean the copings with a good-quality soap-based debubbilizer (like our Pattern Prep Debubbilizer). Spray debubbilizer inside the copings and onto a small brush, with which you then clean inside each coping, and then rinse it all with room temp water. INVESTING With metal rings, a 4mm thick ring liner is required or a double thickness ordinary liner. 1

2 Use a high heat, high expansion investment, like Talladium MicroFine 1700 Casting Investment. Dilute the liquid as per instructions, keeping in mind, that you can vary the expansion, by adding more or less water. Less water equals more expansion and vice versa. The expansion is also effected by the temp of your investment and liquid. In the winter use 1 or 2 c/c water less then recommended. Pour the powder into the liquid, and gently mix with a spatula on the vibrator, until all the powder is wet. Leave it on the vibrator for 30 second then mix it under the vacuum for another 30 second. Pour the investment into the ring, when is filled up to the copings, stop and check to see if there are any very small copings which you need to fill in with a small brush. The normal copings will fill in fine if you have angled your copings correctly. Leave the ring on a warm place for 30 min. BURNOUT According to the investment you use, you can use fast burnout ( putting ring in the furnace at 700 C take it up to 950 C and cast (Talladium MicroFine 1700 Investment). Otherwise you can use a convectional burnout, putting it in a cold furnace, take it straight up to 950 C and cast. There is no need to burnout in stages, or heat soak rings, unless they a very large 6X or 9X size. If you use overnight burnout, set the furnace temp to 800 C. When you get in increase the temp to 950 C and cast. It is not advisable to keep the rings at the high temp for longer than 30 min. CASTING Induction centrifugal casting machines are the best for casting Tilite alloys. Pre-heat the crucible in the furnace, set your casting machine to High or Casting Other Alloys. Place the preheated crucible in the casting machine, add the alloy, placing large buttons on the bottom of the crucible and any smaller pieces on top. Start to melt, when the bottom part of alloy is melted, open the lid, and with a long ceramic rod (available from Talladium UK) push the top smaller pieces into the molten alloy. Now take your ring out of the furnace, place it into the casting machine, and melt for another 20 sec. or until the black shadow disappears from the alloy, and cast immediately. 2

3 When casting bulky items, e.g. bridges, it is advisable to drop the ring temperature to 880 C and heat-soak it for 30 mins. Then try to cast it within 5 seconds of taking the ring out of the burning-out furnace. This same method should be used when casting Talladium Tilite Implant Abutments. Please note the ingots will lose their shape, but do not wait for the alloy to go into a ball. The metal does not have a crust on the top and it does not spin. Melting with Oxy- Propane torch is also good, but you need an multi-orifice torch which give you volume of heat but not high intensity. Set the oxygen to high 35 psi and the Propane very low at 2 psi. High oxygen use will give you very clean casting. Place preheated crucible and alloy in the casting machine, this time place the small pieces of alloy (cut up sprues etc) on the bottom of the crucible and the large buttons on the top. Heat up the alloy to a bright orange color, now take the ring out of the furnace, place it into casting machine, now bring your torch lower down and over the alloy, until ingots loose shape, and the top of the alloy starts moving cast. QUENCHING By the time the casting machine stops spinning, the casting button should be red in color, and the ring is ready to be quenched in cold water. Leave it in the water for 10 sec. only, do not saturate the investment with the water as it would be more difficult to divest. The investment should be hot enough to dry up again. Leave to cool down so you can handle it. Break up the investment. Get the investment out of the copings with an old TC fissure burr or by sandblasting. By quenching, the alloy will soften making it easy to trim and finish. Later on during porcelain firing, the alloy will harden to its normal state. TRIMMING AND FINISHING Cut off the sprues using a thin cut off disc 0.4 or 0.7 mm. If you have tapered your sprues it should be an easy job. Fit the copings down first they should fit without any grinding from the inside. If care was taken during wax up, very little finishing is required now. All that is necessary is to roughen up the surface and to take off the casting oxide which is only grey in colour. The fastest way is to use cut off disc 1.0mm and just slide it across the surface at about 1000rpm low speed, this will give you an even rough surface perfect for porcelain bond. 3

4 SANDBLASTING Sandblast the surface that will take the porcelain with Aluminum Oxide 50 microns. White aluminum oxide will do the job, but to get maximum bonding strength, Brazilian Reddish-Brown Aluminum Oxide is recommended (available from Talladium U.K.). Ferric residue from Reddish Brown Aluminum Oxide is left on the surface of the metal work, and this increases the bond strength, between porcelain opaque and Tilite. Clean the metal work in distilled water in an ultrasonic or by steam cleaner. DEGASSING- OXIDIZING To get desirable oxide to the surface of the metal work, place the metal work in the porcelain furnace at 600 C and take it up to 982 C under vacuum. No holding time or 30 sec. The color of the copings should be light gray to straw gold. If it is: Metallic blue colour, the temp was too low, put it back in the furnace and raise temp by 10 C Rusty Brown color= the temp. was too high, sandblast the surface and place it back in the furnace at 10 C lower temp. There is also going to be colour differences with different thicknesses of metal work. You can degass all the single copings in one batch, and bridge units and thick coping in another. Do not sandblast after degassing. OPAQUE APPLICATION Apply first opaque layer at normal thickness, place it in the furnace at 600 C and raise it in 6 min to the 1020 C under vacuum. No hold time or 30 sec. This higher temperature is necessary to get a good bond between opaque and Tilite. The second opaque, and all porcelain firing should be done to the porcelain manufacturers instructions. 4

5 PORCELAIN APPLICATIONS In general if you expect to use more than the normal number of porcelain firings (with Bridges etc.) start with a little lower temp. and reduce hold time at the high temp. In general don t hold it longer than 30 sec at the time. Each time you fire the porcelain more glass is created inside the porcelain. Too much glass will make the porcelain very hard and therefore prone to cracking. TILITE ALLOYS can be used to cast to Precision Attachments and Implants made from Platinum - Iridium Alloys with melting point of 1593 C or higher. 5