“Building” the Appliance

Dr. Rob Veis

First, specify the Appliance type. Make sure to indicate whether you are designing an appliance for the UPPER or LOWER arch. Think about whether you want to use a REMOVABLE or a FIXED appliance. Some of the factors that will help you make a decision are found in chapter one (The Anatomy of an Appliance) of the textbook. Once you have made a decision, indicate your choice on the prescription. NOTE: If you only give a specific appliance number or name, the lab will make the appliance exactly as it is described in the textbook unless you take the time to modify the design by providing specific desired details.

The Components

Bonded composite ledge to create retention.

Recurved springs. Lap springs.

Soldered "C" clasp. Adams clasp.

Expansion Screws – One of the active appliance components, screws come in many sizes and designs. Review pages 1.14 - 1.18 and Chapter Eight (Arch Development) in the textbook to select the proper screw and placement. When using micro and mini screws, don’t forget to indicate the tooth number and position.

Springs – Review pages 1.11 - 1.13 for the many types of springs available. List the tooth number you are trying to move next to the spring you have chosen. For mesial and distal kicker springs, make sure to indicate whether you want them coming from the labial bow or from the lingual aspect of the appliance.

Bonded Buttons or Hooks – For bonded buttons or hooks, list tooth number, intended position of bonded component, and direction you want to move the tooth. For Fixed/Removable appliances, bonded components must not interfere with seating the appliance.

Labial Arch Wires – Used for appliance retention, to passively retain teeth, or to actively move teeth. Review pages 1.5 - 1.8 to select a desired design and arch wire placement.

Clasps – As the main method of retention, correct clasp selection and placement are essential. Refer to pages 1.1 - 1.4 for clasp selection. Remember, it is important to place some form of retention as close as possible to the active part of your appliance. Simply list the tooth number next to the clasp type on the prescription.

Acrylic – Stability, strength, comfort, and possible effect on speech all affect an appliance’s acrylic component (can also add colours and designs for better patient motivation). See pages 1.9 - 1.10 in the textbook. Make sure to indicate on the model where you want the acrylic finish line.

Bite Planes - Jumping anterior and posterior crossbites, increasing appliance retention, and repositioning the mandible are just a few reasons to use a bite plane. Always provide the lab with an accurate construction bite.

Habit Control Devices – Review Chapter Three (Habits) to select the best device to control thumb sucking, tongue thrusting, cheek biting, or bruxism. Always indicate the exact position and height of the habit device on the model and include an opposing model.

Rest Seats – Indicate the tooth number and the position (i.e. mesial fossa, lingual groove) where you want the rest placed. Take an opposing cast so you and the lab can make sure that there is enough clearance to place the rest.

Bands – Indicate tooth number for teeth to be banded (if using your own bands, indicate which band is for which tooth). PLEASE DO NOT POUR UP MODEL WITH BANDS IN PLACE – just tape bands to lab slip.

Lingual Arch Wires – Used to maintain space. Can also have a number of active components attached to them (Note: need to be able to remove the arch wire to make adjustments). Review pages 1.23 - 1.25 when designing.

Teeth - Every partial has specific demands for tooth placement (active tooth movement, immediate extraction case, etc.). DO NOT MAKE THE LAB GUESS — Tell the technician how you want the teeth placed. Indicate shade, mold, tissue contouring, placement, and any other pertinent information.

Positioners – To accommodate everyone’s individual needs, Space Maintainers has a separate lab slip for designing a positioner for orthodontic finishing. Just call and request yours.