CLINICAL ANALYSIS OF A CHROMATIC SCALE FOR APPLICATION IN FACIAL PROSTHESES: OBSERVATIONAL STUDY

• Grant number: 25/08679-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2025
• End date: June 30, 2026
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Cláudia Helena Lovato da Silva
• Grantee: Monise Barbuzano Lisi
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Oral and maxillofacial prosthetics is a specialty in dentistry that aims to restore quality of life and well-being to patients who have lost parts of their face. Colorless silicone (polydimethylsiloxane) is the material commonly used to make prosthetics, and dyes are added to make the material aesthetic. Color selection is a major challenge for professionals due to the difficulty in achieving color compatibility between the prosthesis and the patient's face. The objective of this study will be to evaluate the clinical performance of a color scale for physical prosthetics that provides practicality and predictability to professionals specialized in color selection. The scale obtained in a previous study based on the skin color of 180 individuals will be applied to 40 participants, distributed into 4 groups according to the Individual Typology Angle (ITA) (n=10). The evaluation will be performed by 3 dentists with experience in the area of ¿¿oral and maxillofacial prosthetics and 3 laypeople. The response variables will be A) Degree of accessibility and B) Degree of perception; the variation factor will be in 4 levels (ITA): Type 1 - Very Light and Light; Type 2 - Medium; Type 3 - Tanned; Type 4 - Dark and Very Dark. The identification of skin color types will be performed using a spectrophotometer in the region of the zygomatic protuberance. For each participant, a specimen from the scale will be selected and will be positioned over their zygomatic prominence. Those evaluated, with normal trichromatic vision capacity, will be positioned 60 cm from the participant and will be instructed to look at a card with 18% gray coloration (RGB: 118, 118, 118) before visual inspection and then look at the spectrum on the participant's face for 5 seconds. The responses will be recorded on a specific form containing the scores 3- There is no difference; 2- Different, but acceptable; 1- Different and not acceptable. From these scores it will be possible to calculate the degree of accessibility (GA = Number of scores 2 or 3/Total number of scores) and the degree of perception (GP = Number of scores 3/Total number of scores). The data obtained will be grouped in tables and examined for statistical analysis using SPSS software (22.0). After assessing the distribution of the data for normality (Shapiro-Wilk test) and homoscedasticity (Levene test), the type of statistical test to be used will be defined, considering a 95% confidence interval.