Banca de DEFESA: RODRIGO FALCÃO CARVALHO PORTO DE FREITAS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : RODRIGO FALCÃO CARVALHO PORTO DE FREITAS
DATE: 21/10/2022
TIME: 08:30
LOCAL: DEPARTAMENTO DE ODONTOLOGIA - AUDITÓRIO
TITLE:

Complete dentures digital workflow:

Biomechanical properties and development of a novel workflow

KEY WORDS:

Keywords: Complete Dentures, 3D Printing, Computer Aided Design/Computer Assisted Manufacturing, CAD-CAM.

PAGES: 124
BIG AREA: Ciências da Saúde
AREA: Odontologia
SUMMARY:

Complete denture (CD) rehabilitation is the most usual prosthodontic treatment for patients with edentulism. Currently, CDs are mainly designed and fabricated using conventional methods, which involve a broad series of clinical and laboratory procedures. In this context, new digital features like subtractive and additive manufacturing can promote breakthroughs by reducing the time and cost of making CDs. Thus, this study aims to investigate surface characteristics (roughness and contact angle), mechanical properties (mini-flexural strength), and biofilm adhesion on computer-aided design/computer-aided manufacturing (CAD-CAM) PMMA polymer, and three-dimensional (3D) printed resin for denture´s base fabrication as well as to propose an innovative workflow. For in vitro analysis, a total of 60 discs and 40 rectangular specimens were fabricated from one CAD-CAM pre-polymerized PMMA disc (GM), one 3D-printed (GP), and two conventional heat-polymerized (GCL and GCV) materials for denture base fabrication. Roughness was determined by the Ra value; the contact angle was measured by the sessile drop method; the mini-flexural strength test was a three-point bending test while the biofilm formation inhibition behavior was analyzed through C. albicans adhesion. The data were analyzed using descriptive and analytical statistics (α = 0.05). Results showed that 3D-printed specimens presented the highest surface roughness (Ra: 0.317 ± 0.151 μm) and lowest mini-flexural strength values (57.23 ± 9.07 MPa) and the CAD-CAM PMMA group showed the lowest C. Albicans adhesion (log CFU/mL: 3.74 ± 0.57) and highest mini-flexural strength mean (114.96 ± 16.23 MPa). There was no statistical difference between CAD-CAM pre-polymerized resin and conventional groups for roughness, contact angle, and mini-flexural strength. In turn, the presented novel workflow for complete dentures fabrication reached a three appointments protocol in which preliminary impressions are made in the 1st session, all together to maxillary registration of lip support, occlusal plane, and reference lines for teeth arrangement. A trial denture is manufactured and evaluated by the 2nd appointment through conventional or CAD-CAM procedures, allowing esthetics evaluation, final impression, and maxillomandibular relationship record and providing precise references for final dentures fabrication. Based on the findings of this in vitro study, CAD-CAM milled PMMA polymers presented surface and mechanical properties similar to conventional resins and show improved behavior preventing C. albicans adhesion, while 3D printed acrylic specimens exhibited the lowest flexural strength, and highest surface roughness. The proposed device for CD´s fabrication clinical procedures reached feasibility to be used either by conventional workflow or by CAD-CAM technology and, by simplifying available techniques, this protocol could achieve reliability and predictability to produce precise complete dentures with reduced working time.

 

 

COMMITTEE MEMBERS:
Presidente - 1459400 - ADRIANA DA FONTE PORTO CARREIRO
Interno - 1640419 - RODRIGO OTHAVIO DE ASSUNCAO E SOUZA
Externo à Instituição - SANDRA LÚCIA DANTAS DE MORAES - UPE
Externo à Instituição - TÚLIO PESSOA DE ARAÚJO - UFPB
Externo à Instituição - VINICIUS DUTRA - IUPUI