Wear a dust mask to avoid inhaling acrylic dust from grinding with the Dremel®.
11. Since more dental acrylic is going to be added (pink gum color), we want to prevent it from bonding to the teeth.
12.
 |
Mix У4 oz. of Al-Cote® separator with У4 tsp. of glycerin. Brush four coats onto any surface you don’t want the gum color to adhere to. Make sure that each coat is completely dry before adding the next.
13. Mix the gum color and when it begins to thicken slightly, pour it into the mold and then press the positive into the mold. When the excess acrylic gets spongy and bounces back when you press into it (return memory), you can demold the positive.
14. Cut around each tooth at the gum line and the vestibule area (small cavity where the midline frenum muscle attaches the upper lip to the gums) with an X-acto® knife (#11 blade).
15. Carefully remove the gum acrylic from the teeth, front and back, as well as gum material that is covering the soft palate. Note: This might be easier said than done. Then remove the appliance from the positive and do a rough trim with the Dremel,® grinding almost to the base of the teeth on the back side. Be careful not to grind through the acrylic and into the stone positive!
16. As an additional anchoring option, you can add a ball clasp to the appliance to help hold it in place, but it is not an essential step. Carefully bend the clasp into a curve that will fit around the back tooth of the appliance. Glue the wire in place with a drop of Superglue.®
17. Use the Dremel® to remove a section of the gums so that the appliance can be placed back on the stone positive without affecting the placement of the clasp.
18. Release the area of the positive with a bit of petroleum jelly and place the appliance back on the positive. Mix up some new pink gum acrylic and carefully rebuild the gum over the wire clasp. When the acrylic has begun to set, place it in hot water to cure.
19. Use the Dremel® to smooth out the new gum acrylic to match the rest of the appliance. Also grind down any high spots or rough areas on the inside. Be careful not to grind a hole in the appliance! Sand any rough edges with high grit wet/dry paper.
20. Use the same 400 and 800 grit paper to sand the front of the teeth and gums; then use a fine grit silicone point bit over the appliance, followed by a bristle brush bit to clean off any silicone residue. Then use a rag wheel bit with some acrylic polish to buff the appliance to a shine.
21. Use an old toothbrush and some dishwashing liquid to remove any remaining polishing compound from the appliance. The last step before painting the teeth will be to reline the inside of the appliance with a soft acrylic.
22. Brush a thin layer of petroleum jelly over the front and back of the positive. Then mix some Flexacryl (2:1) with monomer. The flexible nature of Flexacryl will make the appliance more comfortable to wear. Work quickly; this could set up rather fast.
23. Rub the inside of the appliance with a Q-tip® dipped in monomer, then place the Flexacryl evenly on the inside of the appliance before placing the appliance onto the positive. Clean up any excess with another Q-tip® dipped in monomer. Cure the acrylic in hot water and remove it. Then trim the excess, and it’s ready to paint and wear!
Don’t leave the appliance on the positive for several hours or overnight without removing FIGURE 6 27 it at least once after the acrylic has cured. If you don’t remove the appliance from the
Seams on Neill Gorton positive soon after curing, you will never get it off the positive! You don’t need to ask me
age appliance prior to how I know this, either.
cleanup. Photo by the author.