Influence of restorative technique on the appearance of a dark halo around class III restorations, in vitro study

• Grant number: 17/27116-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2018
• End date: December 31, 2018
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Principal Investigator: Sergio Kiyoshi Ishikiriama
• Grantee: Beatriz Roza Canin
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil

Abstract

One of the greatest challenges of aesthetic restorative dentistry is perfectly mimic dental structures with invisible restorations, in Class III cavities in particular, the frequent appearance of a surrounding dark halo may compromise the results. This study intends to evaluate different techniques and restorative approaches proposed in the literature to camouflage this dark halo. The study will present two variation factors: extension of the bevel in two levels: 1mm and 2mm; and restorative technique in four levels: 25%, 50%, 75% percent of bevel coverage with opaque resin and a technique of making an "inner mirror". The response variable will be the dark halo determined by a 3-level score. Eighty bovine incisors will be prepared with Black class III cavities of standardized size and restored with composite resin. The groups (n = 10) will be differentiated based on the of the bevel at the margin (1 or 2mm) and in the restorative technique. The specimens will be stored in distilled water for 7 days, then calibrated examiners, blind to the groups of each specimen, will evaluate the presence or absence of a dark halo through scores. The specimens will be evaluated clinically and through digital photographs on a dark background. The results will be submitted to a two-way ANOVA and to Tukey test for multiple comparisons.