Physicochemical properties of an experimental calcium hydroxide paste and penetrability in intraradicular dentin

• Grant number: 24/19709-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2025
• End date: January 31, 2026
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Gustavo Sivieri de Araújo
• Grantee: Heloisa Bento Bodini
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

Endodontic treatment in teeth with apical periodontitis aims to decontaminate the root canal system, where strategies such as biomechanical preparation of root canals, sodium hypochlorite irrigating solutions and intracanal medication are employed. However, even with these strategies, the root canal is not totally exempt from contamination by microorganisms, such as Enterococcus faecalis, because they have defense mechanisms and resistance to conventional treatments, such as the presence of a proton pump in the cytoplasmic membrane, allowing the stabilization of its internal pH. The objective of the present study is to evaluate the influence of an experimental intracanal medication based on calcium hydroxide [Ca(OH)2], associated with a proton pump inhibitor, whether or not it is agitated with ultrasound (US). The penetration of the intracanal medication into the dentin tubules will be evaluated, as well as the physicochemical properties (pH and solubility) of the intracanal medications. 18 cattle (n=3), prepared biomechanically, will be used. Experimental groups: G1-BMP + Propylene glycol (Control); G2- BMP + Propylene Glycol + US; G3- BMP + Ca(OH)2 ; G4- BMP + Ca(OH)2 + US; experimental G5- BMP + Ca(OH)2 ; G6- BMP + Ca(OH)2 experimental + US. The penetrability will be evaluated by means of Confocal Fluorescence Microscopy for the different root thirds, where the dentin content will be stained with Fluorescence and propylene glycol and Ca(OH)2 medications with 0.01% Rhodamine (n=3). For pH analysis, 30 polyethylene tubes (n=10) will be filled with Ca(OH)2 medications and immersed in distilled water for 1, 3, 7, 14 and 21 days. The solubility of the medications will be evaluated after 14 days of immersion.