Digital functionally generated path technique in a tardive dyskinesia patient

Abstract

Introduction: This case report illustrated the use of the functionally generated path technique (FGP) to trace the path of movement of occluding surfaces of opposing arches and to achieve harmonious occlusion with no or minimal need for intra-oral adjustments in a tardive dyskinesia (TD) patient. Case Description: A 40-year male with a medical history of tardive dyskinesia visited the hospital to receive oral rehabilitation for missing maxillary anterior teeth. Gypsum cast was digitalized using a desktop scanner and an interim prosthesis was fabricated by CAD/CAM devices. During try-in, the occlusal one-third of the interim prosthesis was trimmed and an auto-polymerizing acrylic resin was applied on the occlusal surfaces and inserted in the patient's mouth. Then, the patient was instructed to perform lateral and protrusive movements in succession to record the patient's functional jaw movements. When the resin was hardened, the modified interim prosthesis was removed and digitized using an intraoral scanner in polygon (PLY) format. Thereafter, the superimposition of the virtual master cast to the intraoral scan was done using a design software program, and the design for the definitive prosthesis was modified according to the altered interim prosthesis. Discussion: In patients with TD utilizing the FGP technique can help to eliminate occlusal interferences during lateral movements and disperse the load applied to teeth during functional movements to establish balanced occlusion. The double scan technique was used to acquire a better marginal fit of the prosthesis. Conclusion/Clinical Significance: FGP with double scan technique can help in fabricating fixed prosthesis with harmonious occlusion in a tardive dyskinesia patient.