Effect of different solutions of chlorhexidine on the production and mechanical stability of resin-caries affected dentin bonds

• Grant number: 10/20495-6
• Support Opportunities: Regular Research Grants
• Start date: October 01, 2011
• End date: September 30, 2013
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Josimeri Hebling Costa
• Grantee: Josimeri Hebling Costa
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated researchers: Carlos Alberto de Souza Costa ; Débora Lopes Salles Scheffel ; Hérica Adad Ricci

Abstract

The aim of this study, which is divided in three experiments, is to evaluate the effect of chlorexidine in different excipients, ethanol or water, in the production and mechanical stability of resin-caries affected dentin bonds. Exper. #1: It will evaluate the effect of chlorhexidine in aqueous or alcoholic solution on the humectability of noncarious and caries-affected dentin by a bonding system. Flat surfaces of dentin will be prepared in 100 noncarious human third-molars, from which 50 will undergo a microbiologic process of caries induction. For each substrate condition, noncarious and caries-affected dentin, surfaces will be randomly divided in 5 groups (n=10): with smear layer (SL), without SL impregnated with water, without SL impregnated with chlorexidine in water, without SL impregnated with ethanol and without SL impregnated with chlorexidine in ethanol. Contact angles between the dentin surface and the adhesive Single Bond 2 will be measured by a goniometer. Exper. #2: The exposure of collagen fibrils in resin-noncarious and -caries-affected dentin bonds will be evaluated after using chlorhexidine solutions in different excipients. Flat surfaces of dentin will be produced in 24 noncarious human third molars. Half of the surfaces will be artificially decayed. The teeth will be randomly divided (n=3) according to the chlorexidine solution (as described above) applied on the acid etched surface and according to the type of substrate used for bonding. Specimens will be produced from each tooth and histologically prepared for Goldner Tricromic staining. The collagen zone exposed at the base of the hybrid layer will be quantified under a light microscope. Exper. #3: The null hypothesis that the use of different solutions of chlorhexidine does not interfere in the mechanical stability of resin-dentin bonds produced in caries-affected dentin will be tested. Flat surfaces of dentin will be produced in 72 noncarious human third molars, which will undergo a biologic protocol to induce tooth decay by S. mutans. The teeth will be divided in 12 groups (n= 6) according to the adhesive system (Single Bond 2, Prime & Bond NT e Excite) and the dentin treatment after phosphoric acid conditioning: chlorhexidine in ethanol, chlorhexidine in water, ethanol only or water only (control). After applying the adhesives, specimens with 0.81 mm² cross-sectional areas will be obtained and subjected to microtensile bond strength testing, immediately after their production or 6 months after storage in artificial saliva. For all experiments, the statistical tests will be selected according to the number and type of the independent variables, as well as according to the characteristics of the dependent variable. The significance level of 5% will be used for all statistical tests. (AU)

Scientific publications

(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)

RICCI, H. A.; SCHEFFEL, D. L. S.; DE SOUZA COSTA, C. A.; DOS SANTOS, F. J.; JAFELICCI, JR., M.; HEBLING, J.. Wettability of chlorhexidine treated non-carious and caries-affected dentine. AUSTRALIAN DENTAL JOURNAL, v. 59, n. 1, p. 37-42, MAR 2014. (10/20495-6, 10/09802-4)

RICCI, HERICA ADAD; SALLES SCHEFFEL, DEBORA LOPES; MARIUSSO, MATHEUS RACY; PALOMARI SPOLIDORIO, DENISE MADALENA; DE SOUZA COSTA, CARLOS ALBERTO; HEBLING, JOSIMERI. Exposed Collagen In Resin Bonds to Caries-affected Dentin After Dentin Treatment with Aqueous and Alcoholic Chlorhexidine Solutions. Journal of Adhesive Dentistry, v. 16, n. 1, p. 21-28, 2014. (10/20495-6, 10/09802-4)