This research, composed of two studies, will evaluate the in vitro erosive effect of hydrochloric acid (HCl) in gaseous and liquid form on the enamel and the effectiveness of different methods of prevention; and the in situ erosive effect of gastric juice on the enamel in patients with gastroesophageal reflux disease (GERD) as well as the effectiveness of different methods of prevention. In the in vitro study, 252 fragments of bovine enamel (4x4 mm) will be obtained and will have half of the enamel surface isolated (control area) and the other half subject to the preventive treatments and/or erosive challenges. The specimens will be divided into Groups (G) - A: exposure to liquid HCl and B: gaseous HCl. Each group will be divided into nine subgroups (Sg) according to the following treatments: Sg1 - control; Sg2: application of fluoride gel; Sg3: fluoride varnish; Sg4: CO2 laser irradiation; Sg5: CO2 + fluoride gel; Sg6: CO2 + fluoride varnish; Sg7: Nd:YAG laser; Sg8: Nd:YAG laser + fluoride gel; Sg9: Nd:YAG laser + fluoride varnish. The erosive challenge will be performed through exposure of specimens to liquid and gaseous HCl, pH 2 at 37oC, 4 times daily for 5 days for a period to be determined. The response variables will be subsurface microhardness, wear depth, DRX, SEM-EDS. In the in situ study, 240 fragments of bovine enamel (4x4 mm) will be obtained and will have half the surface isolated (control area) and the other half treated with the most effective preventive method, according to results of in vitro study. The specimens will be fixed in the palatal region of interocclusal plates that will be used by 30 volunteers: G1 (control) - patients with no signs of dental erosion and GERD; G 2 - patients that present and were diagnosed with GERD; G 3 - patients with dental erosion, but no diagnosis of GERD. This study will be a crossover design, placebo-controlled, randomized and double-blind, composed of two phases of 30 days with a washout period of 7 days. The response variables will be subsurface microhardness and wear depth. (AU)
Articles published in Agência FAPESP Newsletter about the research grant:
(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)
FARAONI, JULIANA JENDIROBA;
DE ANDRADE, JULIA BARONE;
MACHADO DE MATOS, LAIS LOPES;
PALMA-DIBB, REGINA GUENKA.
Effect of Duodenogastric Reflux on Dental Enamel.
ORAL HEALTH & PREVENTIVE DENTISTRY,
Web of Science Citations: 0.