Thicker occlusal splints are usually rough-cut with suitable rotary instruments, then shaped with appropriate carbide burs or similar cutting tools. Finishing instruments such as Lisko or Liskosil can be used…
FAQ Category: Cutting, Trimming and Finishing
How do I finish the edges of a thermoformed appliance?
After establishing the final trim line, remove sharp or irregular areas and progressively smooth the edge using tools suited to the material. The finished margin should be comfortable against the…
How do I polish thermoformed PETG?
Use finishing and polishing tools designed for thermoplastic dental materials and work with light pressure to avoid generating heat. PETG can soften or smear if it becomes too hot. Progress…
How do I prevent rough edges on a retainer?
Use sharp cutting instruments, create a smooth continuous trim line and refine the edge with fine finishing tools. Avoid jagged cuts and sharp internal corners because they can irritate the…
How close should I trim a retainer to the gingival margin?
The correct trim design depends on the orthodontic protocol and desired retention. Some retainers follow the gingival margin closely, while others extend onto the gingiva to increase rigidity and retention.…
How do I remove a tight appliance from a printed model?
Rough-trim excess material first so the formed sheet is not locked around the full model base. Then separate the appliance gradually using a controlled technique rather than excessive flexing or…
Can thermoformed appliances be automatically trimmed?
Automated and digital trimming systems are increasingly available, particularly for high-volume aligner production, but manual trimming remains common in practices and laboratories. Scissors, HSS drills, carbide burs and dedicated finishing…
What is the best way to remove a thermoformed appliance from the model?
Allow the material to cool fully, then make an appropriate rough cut so excess material no longer locks the formed sheet around the model. Separate the appliance carefully rather than…
How do I cut a thermoformed dental appliance?
Cutting technique depends on material and thickness. Thin retainers and aligners can often be rough-trimmed with suitable scissors or fine rotary instruments. Thicker splints usually require rotary cutting instruments, followed…
What tools are best for trimming retainers?
Thin retainers can be trimmed with specialised scissors where the margin is relatively straight, or with fine HSS drills and rotary instruments where the trim line follows the gingival contour.…