Influence of tongue pressure on the obturator prosthesis for soft palate defects: a 3D-FEA study
10.14368/jdras.2023.39.2.61
- Author:
Aein MON
1
;
Mi-El KIM
;
Young-Jun LIM
;
Myung-Joo KIM
;
Ho-Beom KWON
Author Information
1. Dental Research Institute and Department of Prosthodontics, School of Dentistry, Seoul National University, Seoul, Republic of Korea
- Publication Type:Original Article
- From:Journal of Dental Rehabilitation and Applied Science
2023;39(2):61-68
- CountryRepublic of Korea
- Language:English
-
Abstract:
Purpose:The purpose of the study was to analyze how swallowing tongue pressure affects the biomechanics of a velopharyngeal obturator prosthesis and compare its displacement across different occlusal rest positions.
Materials and Methods:A 3D geometric model consisting of the maxilla, teeth, soft palate, and a portion of the pharynx was developed based on the CBCT and MRI data.A defect was created by the resection of soft palate portion. Two experimental models were generated based on two different velopharyngeal obturator designs: one “with mesial occlusal rests” (Model 1) and the other with “distal occlusal rests” (Model 2). A pressure of 25 kPa was applied at the surface of the bulb of the obturator prosthesis opposite the base of the tongue to simulate tongue pressure during swallowing. The maximum von-Mises stress and displacement values of two types of obturator prostheses were analyzed and compared.
Results:The maximum von-Mises stress in the metal framework, located at the posterior palatal strap, was slightly higher in model 1 (64.9 MPa) than in model 2 (54.2 MPa). In both models, the acrylic resin obturator bulb exhibited a maximum stress value of 4.3 MPa. There was no significant difference in prosthesis displacement between the two models, with 31.3 µm for model 1 and 33.6 µm for model 2.
Conclusion:Swallowing tongue pressure had a minor impact on the biomechanics of a velopharyngeal obturator prosthesis, and distal occlusal rests showed a slightly better biomechanical response compared to mesial occlusal rests.
