Banca de DEFESA: Alexia Guimarães Ramos

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : Alexia Guimarães Ramos
DATE: 19/07/2023
TIME: 08:30
LOCAL: Plataforma Teams
TITLE:

“Effect of acid pH on the mechanical properties of materials used for occlusal splints manufacture”

KEY WORDS:

“Occlusal splint; Gastroesophageal Reflux; Bruxism; Sleep bruxism; Temporomandibular Joint Disorders."

PAGES: 100
BIG AREA: Ciências da Saúde
AREA: Odontologia
SUMMARY:

“Among the problems related to sleep and lifestyle, we can mention bruxism and gastroesophageal reflux disorder, which have associations and can occur in the same individual. Gastric acid has an extremely low pH and a high potential for corrosive damage. When in the oral cavity, it can affect teeth and dental materials, such as resins of occlusal splints, which are a reversible, atraumatic and conservative treatment of temporomandibular disorders, in addition to protect the dentition in episodes of sleep bruxism. These devices can be made of different materials, both by analogical and digital flow. Knowledge of how resins for occlusal splints behave when subjected to extremely acidic pH, such as that from hydrochloric acid, is still scarce and can help dentists in the selection of these materials in patients diagnosed with gastroesophageal reflux disorder. associated with other pathologies that require an occlusal splint approach. The objective of this work was to analyze the erosive effect of hydrochloric acid on the surface of resinous materials used for making occlusal splints. The evaluated materials were divided into 6 groups: self-curing resin, microwave thermosetting resin, hot water bath thermosetting resin, SmartDent impression resin, Makertech impression resin and milled resin. All samples were evaluated at three times: T0 - after manufacturing; T1 – after 45 hours of erosive challenge (HCL pH=2); T2 – after 91 hours of erosive challenge (HCL pH=2). The groups were evaluated for surface roughness, Vickers microhardness, flexural strength and modulus of elasticity. The data obtained were submitted to the two-way repeated measures ANOVA test for surface roughness and microhardness and two-way ANOVA for flexural strength and elastic modulus, followed by the Tukey Test with a significance level of 5%. For surface microhardness, only the hot water thermopolymerizable group showed an increase in initial values after the erosive challenge, demonstrating higher values when compared to the other groups. For surface roughness, only the Makertech printed group showed an increase. The milled group showed no differences and the other materials tested decreased their surface roughness. For flexural strength, the microwave energy thermopolymerizable resin and milled resin groups decreased their values. The other groups did not show statistical difference at the end of immersion in HCL. For the modulus of elasticity, the resins: self-curing, thermo-curing by microwave energy and milled decreased their values, while the thermo-curing resins by hot water bath and printing did not show statistical difference at the end of the erosive challenge. A divergence was observed between the results obtained in the different tests and with the different groups tested. We conclude that among analogue materials, hot water thermopolymerizable acrylic resin stands out when subjected to erosive challenge. Among the digital materials, the milled group showed more interesting mechanical properties.”

BANKING MEMBERS:
Interna - 3157942 - EVELYN MIKAELA KOGAWA
Interna - 3493627 - FERNANDA CRISTINA PIMENTEL GARCIA
Externo à Instituição - GUSTAVO AUGUSTO SEABRA BARBOSA - UFRN
Presidente - 1291230 - RODRIGO ANTONIO DE MEDEIROS