Dental appliance used inside patient's mouth

摘要

The retention pieces near the recesses (22) have irregular protuberances (24) formed from the material cast during the formation of the recesses. At least part is back-tapered. At least part, or the majority, of the protuberances have a volume equal to a fraction of the volume of the largest recess. The recesses and protuberances have variable shapes, and are unevenly positioned inside a retention part.