Dimensional stability in orbital prostheses obtained by means of reverse prototype in a CAD/CAM system

• Grant number: 06/03765-4
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2006
• End date: April 30, 2008
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Beatriz Silva Câmara Mattos
• Grantee: Beatriz Silva Câmara Mattos
• Host Institution: Faculdade de Odontologia (FO). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Individuals afflicted with facial defects involving partial or total loss of facial organs present functional, aesthetic and psychologic disturbances, with high degrees of handicap and adverse effects depressing their quality of life. There are many instances when the prosthetic restoration through extraoral facial prostheses is the only possible treatment to minimize the disturbances and restore the normal way of life. The prosthetic rehabilitation depends on maxillofacial technician’s artistry and ability to copy the normal contralateral anatomy, applying anthropometric measurements and visual assessment to achieve best symmetry and an aesthetic face. Advances in technology, including a new generation of computerized tomography and three-dimensional model-making rapid prototyping systems allowed new perspectives in maxillofacial prosthetic rehabilitation. The purpose of this project is to develop and evaluate a new technique to fabricate orbital prostheses through CAD/CAM (computer aided design/computer aided manufacturing). Reverse surface prototype of the healthy contralateral side will be used in the conventional manner to the laboratorial production of silicone orbital prostheses. This study will be undertaken on 15 adults volunteers, aged 25 years or more, regardless gender or ethnical group. The individuals will be submitted to facial impression with alginate and two casts made of Class III stone will be obtained in order to simulate the orbital defect in the right and the left sides, totalizing 30 casts. Facial computerized tomography will be performed for each individual and three-dimensional data will be recorded in the axial, sagital and coronal planes (1mm slice). The software InVesalis will generated three dimensional mirrored surface images of the right and left orbital regions and computer aided manufacturing provided by CenPra will generated 30 mirrored surface prototypes. These prototypes will be adapted on the corresponding casts and prostheses will be processed with MDX4-4210 – Dow Corning Silicone. Previously defined anthropometric landmarks will registered in the facial casts and in the silicone orbital prostheses placed in the orbital defects. Three dimension measurements will recorded for the original healthy side and the orbital prostheses side employing sliding calipers (Mitutoyo, Measurement Technology. Three separate measurements will be recorded for each dimension at intervals of not less than 1 week. Data will be submitted to statistical analysis (Anova) to determine whether there were significant differences between dimensions taken from the healthy orbital side and the side rehabilitated by means of the purposed technique. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MARAFON, PRISCILA GALZO; CAMARA MATTOS, BEATRIZ SILVA; LORENZ SABOIA, ANTONIO CARLOS; NORITOMI, PEDRO YOSHITO. Dimensional Accuracy of Computer-Aided Design/Computer-Assisted Manufactured Orbital Prostheses. International Journal of Prosthodontics, v. 23, n. 3, p. 271-276, MAY-JUN 2010. (06/03765-4)